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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 137 (1972), S. 153-169 
    ISSN: 1432-0568
    Keywords: Embryology ; Epithelial autophagia ; Histocytochemistry ; Human palate ; Macrophages ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ultrastructural and a histochemical study of the disintegration of the human fetal palatinal junctional epithelium was carried out. Special attention was focused both on the epithelium proper as well as on participation of the surrounding mesenchyma. Epithelial autophagia was noticed in the form of inclusion bodies with cellular remnants as well as general cellular disintegration. The disintegration was correlated to the cellular activity of acid phosphatase and AS-esterase. The differences between human and non-human material were recorded and discussed. In the surrounding mesenchyma, histiocytes (macrophages) were noticed participating in the epithelial disintegration, while ordinary mesenchymal cells seemed without importance. The study of activity of alkaline phosphatase reveals that the rapidly growing ossification center of the vomer was touching the superior aspect of the epithelial junctional seams, where the epithelial disintegration starts. Based upon the findings the following sequential steps of disintegration were discussed: 1) pressure from the outside (the vomer anlage), 2) epithelial autophagia and 3) heterophagia of epithelial remnants (invading histiocytes). The ultrastructure and histochemistry of the so-called epithelial pearls were described. The intercellular substance of the palatinal processes was found to consist of hyaluronic acid and of chondroitin-4- and/or-6-sulfate. The mutual ratio of the glycosaminoglucuronoglycans was discussed.
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  • 2
    ISSN: 1432-0568
    Keywords: Chick embryo ; Granular pneumocytes ; Granular inclusions ; Lamellar inclusions ; Ultrastructure ; Lung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Les inclusions lamellaires caractéristiques des cellules granuleuses de l'épithélium pulmonaire apparaissent chez le Poulet à 16 jours d'incubation. Elles dérivent d'inclusions granulaires que l'on peut déceler dans l'épithélium dès l'apparition de l'ébauche pulmonaire, à 21/2 jours d'incubation. Nous avons étudié l'évolution de ces deux types d'inclusions lorsque les ébauches pulmonaires sont transplantées sur des hôtes d'âge différent. Lorsque une ébauche pulmonaire jeune (21/2 à 3 jours) est greffée sur un hôte plus âgé (6 jours), l'évolution des inclusions granulaires est fortement stimulée et peut conduire à l'apparition d'organites présentant plusieurs des caractères des inclusions lamellaires. Lorsqu'au contraire, une ébauche pulmonaire est transplantée sur un hôte plus jeune (3 jours), deux cas peuvent se présenter: Ou bien l'épithélium ne contient pas encore d'inclusions lamellaires au moment de la transplantation (ébauche de 14 jours par exemple): le moment d'apparition de celles-ci est alors considérablement retardé et leur différenciation ne devient massive que lorsque les inclusions lamellaires apparaissent dans le poumon de l'hôte; Ou bien les inclusions lamellaires sont déjà différenciées (poumon de 18 jours par exemple): dans ce cas, leur différenciation se poursuit pendant toute la durée de la greffe. Lorsqu'une ébauche pulmonaire est transplantée sur un hôte plus âgé ou plus jeune, l'évolution ultrastructurale de l'épithelium est donc modifiée. Selon les cas, elle est stimulée ou, au contraire, freinée. Des facteurs présents dans le milieu intérieur de l'hôte influencent la différenciation des greffons. Ils pourraient également intervenir dans de développement normal des poumons.
    Notes: Summary The lamellar inclusions of the granular pneumocytes first appear in chick pulmonary epithelium at 16 days of incubation. They are derived from granular inclusions which can already be seen in the epithelium at the time when lung buds become distinct (at 21/2 days incubation). We have studied the fate of these two types of organelles after transplantation of embryonic lungs to hosts of a different age. When a young lung bud (21/2 to 3 days) is grafted into an older host (6 days), the development of the granular inclusions is strongly stimulated, and can lead to the appearance of organelles which exhibit several features characteristic of lamellar inclusions. When an embryonic lung is transplanted to a younger host, two situations can occur: Either the epithelium does not yet contain any lamellar inclusions at the time of transplantation (eg lung at 14 days); these appear after a considerable delay, and differentiate in large quantities only at the time of appearance of the inclusions in the host lungs. Or the lamellar inclusions are already differenciated (eg lung at 18 days), in which case, their differentiation continues in the host. Therefore, when a lung bud is transplanted into either a younger or older host, the ultrastructural development is modified. It is either stimulated or inhibited. Some factors, present in the host internal milieu, influence the differentiation of the grafts. These factors could also play a role in the normal development of the lungs.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 137 (1972), S. 106-113 
    ISSN: 1432-0568
    Keywords: Anterior pituitary ; Mouse ; Tissue culture ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Suitability of an ordinary incubation system for the culture of anterior pituitary tissues of mice was examined by electron microscopy. It was found that this system has many advantages over Trowell's standard technique for tissue culture and is particularly suitable for the short-term culture. In this system the pituitary tissue cultures were maintained well for at least two days in a chemically defined tissue culture medium (TC 199) without any additives. Addition of 20% calf serum to the medium extended the period to up to five days. Any attempts to prolong it further, however, failed because of a massive necrosis and a great loss of the histological integrity. In the cultured tissues there an enhancement of the LTH cells and a suppression of the other granulated types of cells were observed. The follicular cells were found to hypertrophy and to actively participate in phagocytosis of cell debris.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 21 (1972), S. 239-252 
    ISSN: 1432-0533
    Keywords: Ultrastructure ; Myotendon ; Zebra-Bodies (ladder-like structure) ; Rods
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of the adult and foetal human myotendon is described. At the myotendon the muscle fibre is surrounded by plasma and basement membranes which are never penetrated by the adjacent collagen fibrils of the tendon. Increased thickness and electron density of the plasma membrane and the myofilaments which merge with it occur at the myotendon and this electron dense zone corresponds to the terminal Z-line of the final sarcomere of the myofibril. In the adult the muscle fibre near the myotendon may contain nemaline rods and zebra-bodies. The tendon in the foetus shows much more activity of the fibroblasts than in the normal adult. The collagen fibrils of the early foetus are thinner in diameter than at later stages of development. The union of the tendon with cartilage is illustrated.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 21 (1972), S. 68-75 
    ISSN: 1432-0533
    Keywords: Myelinated Nerve ; Venom ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of right sciatic nerves of Swiss white mice was studied after being exposed to a venom solution ofAgkistrodon contortrix laticinctus (broad-banded copperhead) and to 0.9% NaCl solutions for periods of 1, 2 or 3 h. There was some “Wallerian-like” degeneration in all groups of nerves in the experiment. Additional neuropathological changes were noted in the nerves exposed to venom solutions. The connective tissue was affected most severely, while the basal lamina was unaffected. Schwann cells were vacuolated, and in the most extreme case, a type of myelin splitting occurred which was considered as a “demyelinative” effect. The results were compared to those of Martin and Rosenberg (1968) [15] on studies of the giant squid axon. References to additional fine structural studies of various other neuropathies were given.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 21 (1972), S. 109-116 
    ISSN: 1432-0533
    Keywords: Infantile Neuro-Axonal Dystrophy ; Motor End Plates ; Nerve ; Spheroïds ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The authors report the ultrastructure of neuromuscular biopsies in three cases of infantile neuro-axonal dystrophy. The presence of spheroïds in peripheral and intramuscular nerves, but also in the motor end plates allows the diagnostic of this disease, without doing cerebral biopsy.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 21 (1972), S. 253-257 
    ISSN: 1432-0533
    Keywords: Haemangiopericytoma, Cerebral-Secondary ; Histology ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A secondary haemangiopericytoma of the cerebral hemisphere in a woman of 23 is described. It is formed of cells arranged in masses around proliferating blood capillaries, and also in rosette patterns. The tumour cells are separated from the capillary endothelial cells by thick collars of basement membrane in abnormal amounts. The histology of the primary tumour of the sacrum, and of the secondary tumours in the lungs and nervous system, are similar. A metastatic haemangiopericytoma of the central nervous system appears not to have been previously reported.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 10 (1972), S. 38-48 
    ISSN: 1432-0827
    Keywords: Bivalve ; Molluse ; Shell ; Carbonates ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La technique du bombardement à l'aide d'ion d'argon est utilisée pour réduire l'épaisseur de la coquille de carbonate de calcium des bivalvesMytilus etMercenaria pour examen au microscope électronique par transmission et en diffraction électronique; une comparaison est réalisée à l'aide de répliques simples, servant de témoins. Les résultats obtenus confirment les études antérieures de répliques et de microscopie par balayage. De plus, une structure “aérée” est mise en évidence dans la coquille des aragonites, et surtout dans le nacre deMytilus. Cette structure est interprêtée comme un artefact induit par la chaleur, formé par l'inclusion d'eau et de matériel organique, interprétation qui concorde avec les études chimiques et de microscopie électronique.
    Abstract: Zusammenfassung Die Beschießung mit Argonionen wurde angewendet, um die Dicke von Calciumcarbonat-Schalen der zweischaligen MuschelnMytilus undMercenaria zu reduzieren. Diese Technik erlaubte die Ausführung von Transmissions-Elektronenmikroskopie und Elektronendiffraktion, wobei gleiche Proben nach einer bereits bestehenden Methode vorbereitet und als Kontrollen herangezogen wurden. Es wurden zusätzliche Resultate zu den Muschelstruktur-studien erhalten, welche früher publizierte Arbeiten unterstützen, die mit der Abklatschmethode und der Raster-Elektronenmikroskopie ausgeführt worden waren. Zusätzlich wurde eine „schaumartige” Struktur der Muschelaragoniten, besonders im Perlmutter vonMytilus, beobachtet. Da es sich um ein durch Hitze verursachtes Artefakt handelt, wird diese Struktur als Einschlüsse von Wasser und organischem Material interpretiert, was den Befunden von verschiedenen veröffentlichten chemischen und elektronenmikroskopischen Arbeiten entspricht.
    Notes: Abstract Use is made of the argon ion-bombardment technique to reduce the thickness of calcium carbonate shells of the bivalvesMytilus andMercenaria for transmission electron microscopy and electron diffraction, with comparison of single-stage replicas of similar specimens serving as controls. As an additional approach to shell structure studies, it gives results which support earlier published work with both replicas and scanning microscopy. In addition, a “frothy” structure is detected in the shell aragonites, especially inMytilus nacre. As a heat-induced artifact, it is interpreted as representing trapped water and organic material inclusions, an interpretation consistent with several published chemical and electron microscope studies.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 10 (1972), S. 216-222 
    ISSN: 1432-0827
    Keywords: Ultrastructure ; Callus ; Osteoclast ; Endocytosis ; Lysosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La bordure en brosse des ostéoclastes de cals de fractures de rats présente des plissements complexes de la membrane cytoplasmique formant des canaux étroits. L'absorption d'un produit exogène opaque aux électrons (des macromolécules de dioxyde de thorium) s'effectue par l'intermédiaire de ces canaux, par un «courant» membranaire. Les contenus des canaux sont transférés à des lysosomes («granules spécifiques»), situés sous la bordure en brosse. Dans des «régions de transition», adjacentes à cette dernière, l'absorption de dioxyde de thorium se fait par «vésiculation membranaire» (endocytose classique).
    Abstract: Zusammenfassung Der gekrauste Rand der Osteoklasten im Frakturcallus von Ratten besteht aus komplexen Einstülpungen der Plasmamembran, die enge Kanälchen bildet. Die Absorption einer exogenen, elektronisch dichten Verbindung, Thoriumdioxyd, erfolgt durch diese Kanäle, offenbar durch einen „Membranfluß”. Der Inhalt der Kanäle wird zu den Lysosomen („spezifische Granula”) geführt, welche unter dem gekrausten Rand liegen. In „Übergangsgebieten”, welche sich neben dem gekrausten Rand befinden, scheint die Aufnahme der Thoriumdioxydpartikel durch „Bläschenbildung in der Membran” (konventionelle Endocytose) stattzufinden.
    Notes: Abstract The ruffled border of osteoclasts in the fracture callus of rat consists of complex infoldings of the plasma membrane forming narrow channels. Absorption of an exogenous, electron-dense compound, thorium dioxide, has been shown to take place via these channels, apparently through “membrane flow”. The contents of the channels are transferred to lysosomes (“specific granules”) located subjacent to the ruffled border. In “transitional regions” adjacent to the ruffled border, uptake of thorium dioxide particles appeared to occur through “membrane vesiculation” (conventional endocytosis).
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 9 (1972), S. 238-242 
    ISSN: 1432-0827
    Keywords: Dentine ; Ultrastructure ; Tubule ; Tooth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'étude ultrastructurale de la dentine humaine périphérique, de couronnes dentaires de sujets âgés de 11 à 75 ans, a montré trois aspects principaux du contenu des canalicules en coupe transversale. Il s'agit de canalicules apparemment vides, de canalicules contenant un matériel organique annulaire et, enfin, de canalicules totalement remplis d'un matériel organique d'aspect granulaire ou hyalin. Aucune terminaison nerveuse n'est visible à ce niveau.
    Abstract: Zusammenfassung Die ultrastrukturelle Untersuchung von peripherem menschlichem Zahnkronendentin bei Patienten im Alter von 11–75 Jahren hat drei Hauptaspekte des Inhaltes der Dentintubuli gezeigt. Sie bestehen bei transversalen Schnitten aus toten Gängen sowie beim Lumen der Tubuli entweder aus ringförmigen oder ganzausfüllenden Ablagerungen. Im äußeren Dentin wurden keine Nervenendigungen beobachtet.
    Notes: Abstract An ultrastructural study of peripheral human coronal dentin in patients aged 11 to 75 years, has shown main aspects of the dentinal tubular content. In transverse sections, they consist of dead tracts and annular or solid content to the tubular lumen. No nerve endings were observed in the outer dentin.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 9 (1972), S. 296-309 
    ISSN: 1432-0827
    Keywords: Osteoclasts ; Enzyme ; Parathyroid ; Microdissection ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une nouvelle méthode d'isolement d'ostéoclastes est mise au point pour des analyses biochimiques et de microscopie électronique. Pour isoler les cellules par microdissection, des empreintes d'os métaphysaire sont utilisées. Cette méthode, supérieure aux coupes d'os, permet une meilleure préservation cytologique et enzymatique et permet d'obtenir des cellules totales plus faciles à manipuler, avec des résultats plus reproductibles. Par analyse planimètrique de cellules isolées, colorées histochimiquement, il apparait que les ostéoclastes constituent plus de 90% de la masse de l'échantillon. Les concentrations de la phosphatase acide et de certaines enzymes, liées au nucléotide pyridinique, entrant dans le métabolisme de l'acide citrique, sont déterminées dans des échantillons d'ostéoclastes, pesant de 0,2 à 2,0 μg, isolés à partir de rats normaux et parathyroidectomisés. L'activité en aconitase, mesurée en direction de la transformation de citrate en isocitrate, est de 0,5–0,8 M/Kd/H, la plus faible des activités étudiées. Les activités en GDH et NADP-ICDH sont 5 à 10 fois supérieures que celle de l'aconitase, mais seulement un dixième à un tiers de celle de la phosphatase acide, de la déshydrogénase lactique ou malique.
    Abstract: Zusammenfassung Es wird eine neue Technik beschrieben, welche die Isolierung von Osteoklasten für biochemische und elektronenmikroskopische Untersuchungen ermöglicht. Als Ausgangsmaterial zur Zellisolierung wurden Abstriche von Metaphysenknochen benützt. Die Verwendung von Abstrichen bietet gegenüber Knochenschnitten wichtige Vorteile, wie z.B. eine bessere Erhaltung der cytologischen und enzymatischen Eigenschaften sowie die Gewinnung von unverletzten Zellen, welche leichter verarbeitet werden können und besser reproduzierbare Daten ergeben. Durch planimetrische Analyse der histochemisch gefärbten Ausstriche von isolierten Zellen konnte nachgewiesen werden, daß die Osteoklasten über 90% des gesamten Probenmaterials ausmachen. Die Mengen verschiedener Enzyme, welche an Pyridinnukleotid gebunden und am Citronensäuremetabolismus beteiligt sind, sowie der sauren Phosphatase wurden in Osteoklastenproben bestimmt, welche ein Gewicht von 0,2–2,0 μg hatten und aus Knochen von normalen und mit Parathyroidextrakten behandelten Ratten isoliert worden waren. Die Aktivität der Aconitase, welche in der Richtung von Citrat zu Isocitrat gemessen wurde, war mit 0,5–0,8 M/Kd/H die niedrigste aller untersuchten Aktivitäten. Die Aktivitäten der GDH und der NADP-ICDH waren 5–10mal höher als jene der Aconitase, entsprachen jedoch nur einem Zehntel bis einem Drittel derjenigen der sauren Phosphatase, der Laktat- oder der Malatdehydrogenase.
    Notes: Abstract A new method is described by which osteoclasts can be isolated for biochemical and electron microscopic analyses. As a source of cells for isolation by microdissection, imprints of metaphyseal bone were used. The use of imprints provides important advantages over bone sections, including a higher degree of cytologic and enzymatic preservation, and the delivery of whole cells which are more readily manipulated and which yield data that are more readily reproduced. By planimetric analysis of the histochemically-stained isolated cell samples, it was shown that osteoclasts represent over 90% of the sample mass. The levels of several of the pyridine nucleotide-linked enzymes involved in citric acid metabolism, as well as acid phosphatase, were determined in osteoclast samples weighing 0.2 to 2.0 μg isolated from normal and parathyroid-treated rats. Aconitase activity measured in the direction of citrate to isocitrate was 0.5–0.8 M/Kd/H, the lowest of the activities studied. The activities of GDH and NADP-ICDH were 5 to 10 times higher than that of aconitase but only a tenth to a third that of acid phosphatase, lactic or malic dehydrogenase.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Journal of cancer research and clinical oncology 77 (1972), S. 279-291 
    ISSN: 1432-1335
    Keywords: Lung mouse tumors ; Chemical carcinogen ; Ultrastructure ; Pneumocyte II ; Crystalline inclusions ; Interstitial fibrosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The pulmonary tumours induced in Swiss mice by NMUR seem to be constituted for the most part by cells closely related to the granular pneumocytes (pneumocytes II ou B). Other rarer cells, of epithelial bronchiolar aspect, may take part in the proliferation. The ultrastructural study of tumoral cells suggest that their secretory functions are disturbed. The origin of the crystalline intratumoral structures is discussed, as well as their possible relationship with the production of surfactant. The peritumoral areas are characterized by a dense interstitial flbrosis in which the collagen fibers are associated with an elastoid substance.
    Notes: Resumé Les tumeurs pulmonaires induites chez la souris swiss par le NMUR apparaissent essentiellement constituées de cellules apparentées aux pneumocytes granuleux (pneumocytes II ou B). D'autres cellules plus rares, de morphologie épithéliale bronchiolaire peuvent participer á la prolifération. L'étude ultrastructurale des cellules tumorales suggère que leurs fonctions secrétoires sont perturbées. Le mode de formation des structures cristallins intratumorales est discuté, ainsi que leur rapport éventuel avec la production du surfactant. Les territoires péri-tumoraux sont caractérisés par une fibrose interstitielle dense où les fibres de collagène sont associées à uns substance élastoïde.
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  • 13
    ISSN: 1432-5233
    Keywords: Cyclophosphamide treatment ; Guinea pig ; Experimental diabetes ; Immunodiabetes ; Immunosuppression ; Insulin resistance ; Islets of Langerhans ; Precipitating insulin antibodies ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Hyperglycémie, amélioration de la tolérance à l'insuline et modifications considérables à niveau des cellules B et A des ilots de Langerhans ont fait l'objet d'une observation, après immunisation par insuline et adjuvant, en cobayes produisant des anticorps anti-insuline précipitants. Le traitement par le cyclophosphamide inhibait la production d'anticorps anti-insuline, alors que la glycémie et la tolérance à l'insuline restaient aux mêmes niveaux qu'on pouvait vérifier chez les animaux de contrôle non immunisés. Même les îlots de Langerhans semblaient avoir subi des dommages moins importants par rapport à ceux des animaux qui n'avaient pas été traités par le cyclophosphamide.
    Abstract: Resumen En covayos productores de anticuerpos antinsulina precipitantes, tras inmunización con insulina y adyuvante, se ha podido observar: hiperglicemia, aumento de la tolerancia a la insulina y conspícuas modificaciones a cargo de las células A y B de las islas de Langerhans. El tratamiento con ciclofosfamida inhibía la producción de anticuerpos antinsulina, mientras la glucemia y la tolerancia insulínica permanecían en los mismos niveles que podían observarse en los animales de control no inmunizados. Las islas de Langerhans aparecían menos dañadas respecto a las de los animales no tratados con ciclofosfamida.
    Notes: Riassunto Iperglicemia, aumento della tolleranza all'insulina e cospicue modificazioni a carico delle cellule B ed A delle isole di Langerhans sono stati osservati, dopo immunizzazione con insulina in adiuvante, in cavie produttrici di anticorpi anti-insulina precipitanti. Il trattamento con ciclofosfamide inibiva la produzione di anticorpi anti-insulina, mentre la glicemia e la tolleranza insulinica rimanevano agli stessi livelli riscontrabili negli animali di controllo non immunizzati. Anche le isole di Langerhans apparivano meno danneggiate rispetto a quelle degli animali non trattati con ciclofosfamide.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Acta diabetologica 9 (1972), S. 655-687 
    ISSN: 1432-5233
    Keywords: Chinese hamster ; Diabetes ; Glycogen infiltration ; Kidney ; Nuclear glycogenosis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Cette enquête sur l'ultra-structure du rein de hamsters chinois atteints de diabète a permis de relever des lésions glomérulaires légères, consistant en un épaississement non-homogène des membranes basales des vaisseux capillaires, des altérations de cellules de la mésange, une dilatation irrégulière des anses vasculaires. Sur la partie tubulaire, une accumulation de glycogène dans le cytoplasme des cellules de la partie distale et du tube collecteur ainsi que la présence de glycogène dans le noyau des animaux atteints d'un grave diabète et de kétose.
    Abstract: Resumen La presente investigación sobre la ultraestructura del riñón del hamster chino diabético, ha dado la posibilidad de poner en evidencia sutiles lesiones glomerulares, consistentes en el engrosamiento no homogéneo de las membranas basales de los vasos capilares, en alteraciones de las células del mesangio, en la dilatación irregular de las ansas; y, a cargo de la parte tubular, en una acumulación de glicógeno en el citoplasma de las células del tramo distal y del túbulo colector y en la presencia de glicógeno en el núcleo de los animales con diabetes grave y quetosis.
    Notes: Riassunto La presente indagine sulla ultrastruttura del rene di hamsters cinesi diabetici ha fatto rilevare fini lesioni glomerulari, consistenti in ispessimento non omogeneo delle membrane basali dei vasi capillari, alterazioni delle cellule del mesangio, dilatazione irregolare delle anse vascolari. A carico della parte tubulare, accumulo di glicogeno nel citoplasma delle cellule del tratto distale e del tubulo collettore; presenza di glicogeno nel nucleo negli animali con diabete grave e chetosi.
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 159 (1972), S. 87-98 
    ISSN: 1433-8580
    Keywords: Ultrastructure ; Small lymphocytes ; Throracic duct lymph ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die charakteristische Feinstruktur der durch Drainage des Ductus thoracicus des Menschen gewonnenen Lymphocyten wurde beschrieben, ihre Größe und Kern-Plasma-Relation durch planimetrische Verfahren ermittelt. Zwei morphologisch unterschiedliche Formen kleiner Lymphocyten konnten beschrieben werden: Zellen, die durch einen chromatinarmen Kern und relativ lockeres Cytoplasma gekennzeichnet sind, das zahlreiche Zellorganellen (Golgifeld, Centriolen, Mitochondrien und freie diffus verteilte Ribosomen) einschließt, sowie Zellen mit chromatinreichen Kern und dichtem Cytoplasma mit auffallend wenig Mitochondrien, jedoch relativ zahlreichen freien Ribosomen. Eine mögliche funktionelle Bedeutung dieser beiden morphologisch unterschiedlichen kleinen Lymphocyten wird diskutiert. Danach werden die Zellen der ersten Gruppe als differenzierte Zellformen, die der zweiten jedoch als immunologisch aktivere kleine Lymphocyten angesehen.
    Notes: Summary The ultrastructure of small lymphocytes of human thoracic duct lymph is described and planimetric studies of their size and nucleus-cytoplasm relationship are made. Two morphologically different small lymphocytes could be recognized; cells with a nucleus with little chromatin and a relatively light cytoplasm inclosing many organelles (Golgifield, Centriol, Mitochondria, Monoribosomes), cells with compact chromatin and dense cytoplasm including only a few mitochondria but many monoribosomes. The possible function of these morphological different small lymphocytes was discussed. The first group is a well differentiated cellform, the second one may contain more immonulogical active small lymphocytes.
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  • 16
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    Cell & tissue research 123 (1972), S. 458-469 
    ISSN: 1432-0878
    Keywords: Photoreceptor ; Bryozoa ; Larva ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pigmented spots of bryozoan larvae have often been implicated in photoreception due to their preferential occurrence in larvae with positive phototactic behavior. Results of light and electron microscopic studies of Bugula neritina show that the larvae possess two spots, each with a basal sensory cell situated at the base of a pit-like depression. The embedment of the pit and its basal cell in a pad of subepidermal pigment cells allows for directional illumination. The basal sensory cell produces a ball-like mass of non-motile cilia. The configuration of the axoneme is typical of kinocilia and unlike the arrangement previously described for ciliary photoreceptors. Elaboration of receptor organelle membrane surface area is accomplished uniquely by multiple cilia oriented so that large portions of each cilium lie perpendicular to the direction of incident light. The pigmented spot directly contacts the underlying equatorial nerve ring which also connects with the major larval locomotor organ. The pigmented spots of B. neritina are the only potential photoreceptor structures which have been studied by electron microscopy in the three lophophorate phyla. The use of ciliary membranes as the potential photoreceptor organelle allies the bryozoan pigmented spot with the ciliary type photoreceptor which occurs most prevalently in deuterostome animals.
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  • 17
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    Cell & tissue research 124 (1972), S. 217-229 
    ISSN: 1432-0878
    Keywords: Sensory axons ; Dorsal root ganglia ; Rat ; Ribosomes ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the dorsal root ganglia of the rat, ribosomes were found not only in the initial segment, but they were also observed in the axoplasm of intraganglionar myelinated fibres and in the sensory portion of spinal nerves. Axons of seven-days-old rats contained more ribosomes than those of adult animals. The amount of particles decreased gradually from the initial segment trough intraganglionar internodes to the axons of spinal nerves. No ribosomes were found in axons of dorsal roots. In intraganglionar fibres, ribosomal particles were usually observed near the nodes of Ranvier, in the vicinity of Schmidt-Lantermann clefts and in axons near the Schwann cell nuclei. They were arranged in tetrads, pentads or in larger polysomes, and they were often observed adjacent to a group of mitochondria. The particles had invariably a stable size, their average diameters measuring 234 ± 2 × 197 ± 3 Å, which is practically equal to the diameters of 232 ± 2 × 203 ± 3 Å of ribosomes in the Schwann cell cytoplasm. These values fall within the range of diameters of ribosomes isolated from various cells of eukaryotic organisms as given in the literature. Since no other granular component of the cytoplasm has similarly stable dimensions, the measurements are considered to prove that the axonal particles described here are ribosomes.
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  • 18
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    Cell & tissue research 126 (1972), S. 1-16 
    ISSN: 1432-0878
    Keywords: Oocyte ; Rana pipiens ; Ultrastructure ; Cytochemistry ; Enzymes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In early diplotene frog oocytes incubated to illustrate thiamine pyrophosphatase (TPPase) activity, reaction product is uniformly distributed within the compartments of the endoplasmic reticulum and nuclear envelope as well as within the saccules and small vesicles comprising the dictyosomes. With continued oocyte development the reaction product becomes concentrated in localized regions of the dictyosome saccules. Eventually, the enzyme is no longer apparent within the endoplasmic reticulum, but is concentrated in the cisternae of the inner dictyosome saccules. The variations noted suggest that the enzyme is synthesized early in diplotene by the endoplasmic reticulum and is subsequently transported to the Golgi apparatus where it is consistently observed at later developmental stages. TPPase activity is also present in the Golgi apparatus of follicle and theca cells as well as in ovarian epithelial cells. The enzyme is also detected in micropinocytotic vesicles contained within the cells comprising the follicle envelope and in intercellular spaces of the follicle. Horseradish peroxidase injected into the coelomic cavity is transported via micropinocytotic vesicles into and through the cells comprising the follicle envelope and in intercellular spaces. The exogenous protein is not found even after a prolonged time period in early diplotene oocytes. The protein is, however, present in large spherical and “tubular” vesicles in the cortex of vitellogenic oocytes approximately 500 microns in diameter. The possible functional role of the enzyme TPPase during oogenesis is discussed.
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  • 19
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    Cell & tissue research 126 (1972), S. 193-205 
    ISSN: 1432-0878
    Keywords: Spermatozoon ; Chilopoda ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Le spermatozoïde de Lithobius forficatus L. a été étudié grâce aux microscopes électroniques, classique et à balayage. Le spermatozoïde a une longueur d'environ 2 mm et comprend deux parties: la tête, avec l'acrosome et le noyau, et la queue, divisée en zone de liaison, pièce intermédiaire et pièce terminale. L'acrosome, entouré par du matériel fibrillaire exogène, a environ 4 μ de long sur 0,2–0,3μ de large. Le noyau spiralé (300 à 400 μ de long) est constitué d'un axe fibrillaire et d'une spire granulaire dans la région postérieure. La zone de liaison est composée de la partie basale différenciée du noyau et des parties antérieures du complexe flagellaire et de la pièce intermédiaire. La pièce intermédiaire, particulièrement longue (1,5 mm environ) est formée par le flagelle entouré de ses gaines et du manchon mitochondrial. La pièce terminale est un court prolongement flagellaire (6 à 7 μ). Les spermatozoïdes matures (prélevés dans les vésicules séminales) ont une structure mitochondriale légèrement différente de celle des spermatozoïdes prélevés dans le testicule.
    Notes: Summary The spermatozoon of Lithobius forficatus was investigated by transmission and scanning electron microscopy. The spermatozoon has a length of about 2 mm long, it is subdivided into a head with acrosome and nucleus, and a tail with a connecting piece, a middle piece and an end piece. The acrosome, surrounded by exogenous fibrillar material is about 4 μ long and 0.2–0.3 μ wide. The spiral nucleus (300–400 μ in length) consists of a fibrillar axis and of a whorl of granular material in the posterior part. The connecting piece is composed of the basal differentiated part of the nucleus and the anterior parts of the flagellar complex and middle piece. The latter is particularly long (about 1.5 mm) and consists of the flagellar complex and the mitochondrial sheath. The flagellar end piece is short (6–7 μ). Mature spermatozoa (seminal vesicles) have a mitochondrial structure slightly different from those within the testis.
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  • 20
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    Cell & tissue research 127 (1972), S. 1-8 
    ISSN: 1432-0878
    Keywords: Parathyroids ; Anurans ; Crystals ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytoplasmic and nuclear crystalline inclusions are described in parathyroid secretory cells of adult frogs (Rana temporaria L.) and their possible significance is discussed.
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  • 21
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    Cell & tissue research 126 (1972), S. 446-453 
    ISSN: 1432-0878
    Keywords: Eye ; Manduca sexta ; Ommatidia ; Retinula ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The superposition eye of the sphingid moth, Manduca sexta was explored by means of the scanning electron microscope (SEM). Specifically examined were the corneal nipple array, corneal lens, crystalline cones and tracts, photoreceptor cells and their axons. Descriptions of the external ultrastructure of the components were correlated, where possible with previously published accounts of internal ultrastructure as obtained from TEM studies. A key finding was the demonstration of the axial rotation of the eccentrically situated retinular cell, its externally noted prominence and the arrangement of the other photoreceptor cells composing the retinula. Because of the interest in superposition eye theory, the functional significance of various preretinular optic components was reviewed where it specifically related to Manduca.
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  • 22
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    Cell & tissue research 127 (1972), S. 175-188 
    ISSN: 1432-0878
    Keywords: Vitelline membrane ; Chorion ; Ephestia ; Follicle cell ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural studies on developing egg chambers of the moth, Ephesita kühniella reveal that the precursors of the vitelline membrane are synthesized within follicle cells which are in contact with the oocyte. The vitelline membrane precursors appear to be synthesized by the rough-surfaced endoplasmic reticulum, and this material apparently moves to the Golgi cisternae where the definitive vitelline membrane precursor body is produced. The previtelline bodies are then secreted into the spaces between the oocyte and follicle cells, where they fuse to form a continuous membrane. Chorion formation begins with the deposition of a layer of tubules at the outer edge of the vitelline membrane which coalesce to form the inner edge of a thin, striated layer. In subsequent stages, several compartmented layers are rapidly secreted external to the striated layer, giving rise to the mature chorion.
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  • 23
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    Cell & tissue research 128 (1972), S. 303-316 
    ISSN: 1432-0878
    Keywords: Spermatozoon ; Nemertine ; Ultrastructure ; Phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mature spermatozoa of the hoplonemertine, Emplectonema neesii were studied by light and electron microscopy. The spermatozoa are flagellate and motile, each gamete consisting of an elongate anterior head and a posterior flagellar tail. Three regions are identifiable in the head, the acrosome, a nuclear zone and a connecting piece containing two centrioles. The nuclear zone contains glycogen granules as well as an elongate, grooved nucleus and a large mitochondrion whose lobes interdigitate with the nuclear grooves. The flagellum has a typical 9 + 2 flagellar tubule organisation. Nemertine spermatozoan ultrastructure, as exemplified by that of E. neesii, is compared with that of platyhelminth male gametes and the supposed phylogenetic affinity of the two taxeis reexamined in the light of the results of this comparison.
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  • 24
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    Cell & tissue research 128 (1972), S. 241-282 
    ISSN: 1432-0878
    Keywords: Ovary ; Bruchidius obtectus ; Oocytes ; Previtellogenesis ; Ultrastructure ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Im ersten Teil der Arbeit werden die Ovariolen adulter Imagines von Bruchidius obtectus licht- und elektronenmikroskopisch untersucht. Durch den Nachweis von Nährsträngen, die die Oocyten mit den Nährzellen der Endkammer verbinden, konnte erstmals gezeigt werden, daß Bruchidius telotroph-meroistische Ovariolen besitzt. Die Nährzellen, deren Kerne kettenförmige Nukleolen aufweisen, bilden bei den Imagines ein Syncytium, das von einem räumlichen Maschennetz aus interstitiellen Zellen stabilisiert wird. In den Oocytenkernen entsteht während der Prävitellogenese eine Karyosphäre, von der aus „Nukleolarkörper“, Binnenkörper und „segmentierte Längsstrukturen“ gebildet werden. Die „Nukleolarkörper“ und die kettenförmigen Nährzellnukleolen werden als multiple Nukleolen diskutiert. Der zweite Teil der Arbeit stellt eine ontogenetische Untersuchung des Ovariolengewebes dar. Danach entsteht das Nährzellsyncytium in der Phase der Imaginalhäutung aus einem zellulär-fusomalen Verband. Die morphologische Abgrenzung der Ei- und Nährzellen voneinander sowie die Ausbildung von Nährsträngen finden ebenfalls in dieser Entwicklungsphase statt. Die präsumptiven Ei- und Nährzellen durchlaufen auf dem Puppenstadium das Pachytän der Prophase der Meiose. Damit weisen sich die Nährzellen als Keimbahnabkömmlinge aus. Im dritten Teil der Untersuchungen erfolgt eine Analyse der DNA- und RNA-Synthese sowie des RNA-Transports in dem Ovariolengewebe adulter Imagines. DNA Markierungen mit 3H-Thymidin lassen auf einen, wenn auch geringen, Polyploidiegrad der Nährzellkerne schließen. Markierungen mit 3H-Uridin belegen eine hohe RNA-Syntheserate der Nährzellkerne. Mit nahezu gleicher Intensität wie die Nährzellkerne synthetisieren auch die Oocytenkerne RNA, obwohl sie eine Karyosphäre bilden. Mit Hilfe von Markierungsgradienten im Ooplasma sowie von Nährstrangmarkierungen gelang der Nachweis eines RNA-Transportes von Nährzellsyncytium über die Nährstränge in die Oocyten. Abschließend wird das telotrophe Ovar von Bruchidius (Coleoptera-Polyphaga) dem telotrophen Ovar der Heteropteren gegenübergestellt. Der Vergleich legt eine konvergente Entwicklung dieses Ovartyps bei Insekten nahe.
    Notes: Summary In the first part of the investigation the ovarioles of adult imagines are analyzed by light and electron microscopy. It is shown that nutritive cords connect the oocytes with the apical trophic tissue, demonstrating that Bruchidius has telotroph-meroistic ovarioles. The trophic tissue, in which the nurse cell nuclei contain chain-like nucleoli, is a syncytium stabilized by a three-dimensional network of interstitial cells. During previtellogenesis, a karyosphere is formed in oocyte nuclei in which “nucleolar bodies”, endobodies, and “filament bodies” originate. The “nucleolar bodies” and the chain-like nucleoli of nurse cells are considered to be multiple nucleoli. In the second part, the development of the ovariole tissue during ontogenesis is studied. The syncytial trophic tissue derives from a cellular-fusomal organization during the phase of molting. During the same period, the morphological distinction between nurse cells and oocytes as well as the development of nutritive cords take place. Nurse cells are derived from the germ-line, since, during pupal stages, both the prospective oocytes and the prospective nurse cells undergo the prophase of meiosis up to pachytene. The third part is an investigation of DNA- and RNA-synthesis and RNA-transport in the ovariole tissue of adult imagines. DNA labelling with tritiated thymidine shows a small degree of polyploidisation in nurse cell nuclei. By labelling with tritiated uridine, a high rate of RNA-synthesis could be demonstrated in nurse cell nuclei. A similar amount of RNA-synthesis exists in oocyte nuclei, even if they form a karyosphere. The transport of RNA from the apical trophic tissue via the nutritive cords into the oocytes is demonstrated by silver grain gradients over the ooplasm and by the labelling of nutritive cords. Finally, the telotrophic ovary of Bruchidius (Coleoptera-Polyphaga) is compared with the telotrophic ovary of Heteroptera, suggesting a convergent development of telotroph-meroistic ovaries in insects.
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  • 25
    ISSN: 1432-0878
    Keywords: Rectal caeca ; Starfishes ; Epithelium ; Histochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Dans les caecums rectaux des deux espèces étudiées, stratification tissulaire et composition cellulaire sont semblables. L'épithélium interne se compose de mucocytes et de cellules banales. Outre du glycogène, ces dernières renferment chez M. glacialis des grains de mucopolysaccharides neutres associés à des protéines tandis que chez C. tenuispina, les granules contiennent des mucopolysaccharides acides carboxylés et sulfatés également associés à des protéines. L'épithélium externe de C. tenuispina présente, outre des cellules banales, des cellules glandulaires à contenu protéique. Une attention particulière a été apportée à l'ultrastructure du pôle apical des cellules banales internes. On y remarque de nombreuses microvillosités et un flagelle central caractéristique. De plus, on observe très fréquemment des formations pinocytaires ainsi que plus rarement de la phagocytose. Les diverticules seraient donc, chez les Asteriidae, des organes digestifs à part entière se caractérisant par un grand pouvoir d'absorption et une digestion intracellulaire. Enfin, le pôle basal des cellules banales internes, très contourné, contient, par endroit, des β-cytomembranes typiques. Il est possible qu'à ce niveau aient lieu des transferts de substances vers le coelome.
    Notes: Summary Histological and cytological composition are similar in the rectal caeca of both studied species. Internal epithelium is composed of mucocytes and of banal cells. Besides glycogen, these cells contain in M. glacialis neutral mucopolysaccharides associated with proteins, while in C. tenuispina, the granules contain acidic carboxyled and sulfated mucopolysaccharides also associated with proteins. The external epithelium of C. tenuispina presents, besides banal cells, granular secretory cells with proteic content. Special attention has been payed to the ultrastructure of the apical pole of the internal banal cells. One notices numerous microvilli and a characteristic central flagellum. Moreover, one frequently observes pinocytic formations as well as—more rarely—phagocytosis. The rectal diverticula would thus be, in the Asteriidae, real digestive organs provided with a great capacity of absorption and intracellular digestion. The basal pole of the internal banal cells contains from place to place typical β-cytomembranes. Transfers of substances to the coelom can occur at that level.
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  • 26
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    Cell & tissue research 128 (1972), S. 426-437 
    ISSN: 1432-0878
    Keywords: Spermathecal gland ; Silphidae ; Cell types ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Chez les Silphes et en particulier chez Phosphuga atrata, la glande de la spermathèque présente une structure particulière liée à la présence d'une intima cuticulaire tapissant la lumière de la glande. Elle comporte trois types cellulaires: les cellules sécrétrices, les cellules de l'épithélium sous-cuticulaire et les cellules-manchons. Les cellules sécrétrices de grande taille contiennent une invagination de la membrane cytoplasmique formant une «vacuole» extracellulaire bordée de microvillosités. Dans cette vacuole plonge l'extrémité, différenciée en ampoule poreuse, d'un canalicule de nature cuticulaire, qui véhicule la sécrétion jusqu'à la lumière de la glande. Le canalicule est élaboré par une cellule-manchon qui l'accompagne sur toute sa longueur sauf à son extrémité intravacuolaire. Ce type de glande, qui se retrouve chez de nombreux Insectes, y assurant des fonctions diverses (sécrétion odorifique, sécrétion de défense, sécrétion spermale, etc.), est susceptible de nombreuses variations.
    Notes: Summary The spermathecal accessory gland in the female of Phosphuga atrata (Silphidae), exhibits a special structure which is due to the presence of a cuticular intima lining the lumen. The wall of the gland shows three cellular types: the secretory cells, the epithelial cells and the ductule carrying cells. Each large secretory cell contains a cavity formed by an invagination of the cytoplasmic membrane and lined by many microvilli. The secretory cell is connected with a cuticular ductule ending in the cavity of the glandular cell, in a porous organelle. This ductule, which carries the secretory material to the lumen, is surrounded by the ductule carrying cell. This type of integumentary gland is very common in insects, where it assumes various functions (attraction, defense, conservation of sperm, etc.) and its morphology varies considerably.
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  • 27
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    Cell & tissue research 129 (1972), S. 65-75 
    ISSN: 1432-0878
    Keywords: Fetal metanephros ; Renal nerves ; Renal tubules ; Macula densa ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung In elektronenmikroskopischen Untersuchungen an den Nachnieren 13–16 Wochen alter menschlicher Feten wird gezeigt, daß die Macula densa und andere Abschnitte des Mittelstücks der Niere von marklosen Nervenfasern innerviert werden. Nervenfasern gelangen mit den Gefäßen an die Tubuli. Synapsen finden sich innerhalb der Tubulusmembran an der Basis der Tubulusepithelien. Eine Synapse wurde an der parietalen Bowmanschen Kapsel nahe dem Gefäßpol des Glomerulus beobachtet. Die Mehrzahl der bisher am Tubulus beobachteten Axonendigungen scheint cholinergen Neuronen zuzugehören, jedoch ist eine weitere Abklärung in Verbindung mit histochemischen Methoden erforderlich. Die Bedeutung der Innervation für die Funktion des Nephron ist schwer einzuschätzen, zumal experimentelle Untersuchungen hierzu fehlen. Auch Befunde nach Nierentransplantation lassen wegen der möglichen postoperativen Persistenz und Regenerationsfähigkeit intrarenaler Nervenfasern keine eindeutigen Rückschlüsse zu. Möglicherweise ist mit dem Nachweis der Innervation auch das regulierende Agens für den „kontraktilen Apparat“ der Niere bzw. des Nephron gefunden. Interessanter weiterer Befund ist die Beobachtung synaptischer Nerv-Endothel-Kontakte in kleinsten Nierengefäßen (Endarteriolen).
    Notes: Summary Electron microscopic study of the metanephros of 13–16-week-old human fetuses shows that the region of the macula densa as well as other segments of the distal convoluted tubule are innervated by unmyelinated nerve fibers. Nerve fibers reach the tubules alongside blood vessels. Synapses are found within the basal lamina of the tubular epithelia. One synapse was seen in the parietal part of the Bowman's capsule near the vascular pole of the glomerulus. Present evidence suggests mainly cholinergic innervation of the distal tubule, but verification using other histochemical methods is necessary. In the absence of experimental studies, it is difficult to determine the functional role of the innervation of the nephron. Observations after renal transplantation are not conclusive in view of possible postoperative persistence and regeneration of intrarenal nerve fibres. It may well be that innervation controls the “contractile apparatus” of the kidney. Synaptic contacts between axons and endothelial cells of the smallest renal arterioles may also have functional significance.
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  • 28
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    Cell & tissue research 129 (1972), S. 272-277 
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Glycogen ; Rana ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytochemical and morphological evidence indicates the presence of glycogen packets in the condensed nuclei of Rana pipiens and Rana clamitans testicular spermatozoa. A possible reason for its existence is discussed. Glycogen is also demonstrated in the acrosomes of R. pipiens spermatozoa and in the middle pieces and tails of R. clamitans spermatozoa.
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  • 29
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    Cell & tissue research 129 (1972), S. 301-319 
    ISSN: 1432-0878
    Keywords: Insect hemocytes ; Ultrastructure ; Cytophysiology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The wide range of functional activities of circulating and sessile insect hemocytes expresses itself in highly specialized cytological terms. Electron microscopic studies carried out in five species of normal and experimentally manipulated cockroaches, in conjunction with light microscopic information, reveal a broad spectrum of structural organization and an apparent capacity for cellular modulation. In addition to conventional organelles, these hemocytes contain a class of unusual cytoplasmic inclusion bodies which seem to undergo striking transformations in response to specific functional demands. A variety of transitional forms attests to the existence of close links between tubule containing (type 1), electron dense (type 2), and large globular (type 3) inclusion bodies, and reveals the derivation of yet another special (lamellated, fusiform) inclusion from type 2 bodies. Confluence of the type 3 configurations into still larger lacunae may precede the release of their contents into the hemolymph, a process whose major effect seems to be the initiation of the clotting process. Another important activity of hemocytes concerns the programmed reorganization of the stromal framework of the various organs. The dominant feature of blood cells engaged in the deposition of connective tissue are greatly distended cisternae of the rough endoplasmic reticulum and accumulations of banded fibrils at the interface of cytoplasm and extracellular space. The engulfment of discarded stromal material can be visualized in fortuitous sections representing steps in its incorporation by hemocytes. Ultrastructural correlates of the breakdown of these and other disintegrating or noxious elements by certain hemocytes are prominent digestive vacuoles with heterogeneous contents and reaction products of hydrolytic enzymes. The capacity for the uptake of small particles by micropinocytosis is demonstrated by the localization of horseradish peroxidase activity at the cellular surface and within cytoplasmic vesicles. The diversity of structural appearances reflects a division of labor, while the many transitional features of hemocyte morphology favor the concept of functional flexibility of one basic cell type rather than a strict classification into distinctly separate cellular types.
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  • 30
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    Cell & tissue research 129 (1972), S. 548-560 
    ISSN: 1432-0878
    Keywords: Sensory receptors ; Acarina ; Amblyomma americanum ; Palpal organ ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Palps of the tick Amblyomma americanum (L.) (Acarina: Ixodidae; nymphal stage) were studied by scanning and transmission electron microscopy. The terminal palp segment (IV) bears the so-called “palpal organ”, a cluster of 10 short, blunt-tipped sensilla. All sensilla (except for the center sensillum) receive a dual innervation: 2 mechanoreceptive dendrites which terminate in the socket membrane plus several chemoreceptive dendrites (4–12) which enter the lumen. The thick-walled cuticular shaft possesses 2–3 small pore openings (100 Å) below the tip, thus establishing communication between dendrites and environment. Two structurally different types of palpal sensilla exist: The A-type has a characteristic doublelumen and always contains 4 dendrites, the B-type features a single lumen and a specially layered cuticular shaft with 6–12 dendrites. The fine structure of the tick palpal receptors corresponds closely to that of known contact chemoreceptors in insects.
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  • 31
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    Cell & tissue research 130 (1972), S. 302-311 
    ISSN: 1432-0878
    Keywords: Gonadal development ; Sex determination ; Germ cells ; Mollusca ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of the gonad, from hatching through sexual maturity and oviposition, has been studied in Arion ater rufus and Deroceras reticulatum. At hatching, the gonad is comprised of several acini. These acini are hollow structures, the walls of which are generally one or two cell layers thick. This cell layer consists of intermingled germinal and non-germinal cells. Eventually, each acinus is divided into two compartments (cortical and medullar) by a layer of auxiliary cells. The auxiliary cells appear to differentiate into Sertoli and follicle cells. These three non-germinal cell types appear to form an uninterrupted cell barrier that isolates the female germ cells in the cortex from the male germ cells in the medulla. Thus, although these animals are hermaphroditic, the male and female germinal lines differentiate in physiologically isolated compartments.
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  • 32
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    Cell & tissue research 130 (1972), S. 312-317 
    ISSN: 1432-0878
    Keywords: Aphid cornicle ; Basal lamina ; Oenocyte ; Holocrine secretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Light- and electron-microscopic observations on the cornicles of the rose aphid Macrosiphum rosae are presented, and discussed in relation to conflicting interpretations of cornicle structure and function. Lipid filled cornicle secretory cells occupy the lumen of the cornicle and extend into the abdominal cavity. The aphid is readily induced by mechanical stimuli to release cornicle secretory cells from a pore at the tip of the cornicle. The holocrine secretory cells are disrupted and release their lipid contents on leaving the body. They are enclosed within an acellular membranous sac that is apparently identical in structure with the basal lamina of the epidermis. The ultrastructure and anatomical relationships of the cornicle secretory cells suggest that they are oenocytes invaginated with the epidermal basal lamina, and are not anatomically or embryologically related to fat body.
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  • 33
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    Cell & tissue research 130 (1972), S. 205-218 
    ISSN: 1432-0878
    Keywords: Sternal gland ; Trinervitermes geminatus ; Cell types ; Histochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé La glande sternale de Trinervitermes geminatus correspond à un épaississement médian de la partie antérieure du cinquième sternite abdominal. Elle est bordée intérieurement par une fine basale conjonctive et extérieurement par la cuticule, quelques sensilles campaniformes sont également visibles dans la masse glandulaire. On peut y reconnaître deux types de cellules: d'abord des cellules ovalaires situées dans la partie moyenne de la glande. Elles contiennent de grosses mitochondries et des globules denses, et sont en relation avec la basale par quelques fins prolongements cellulaires. Ensuite des cellules cylindriques, bien développées, constituant toute l'épaisseur de la glande. Elles possèdent de nombreuses vésicules de reticulum lisse et une bordure en brosse formée de microvillosités et de digitations cytoplasmiques qui pénètrent dans la cuticule. Cette cuticule comprend une mésocuticule lacunaire et une fine épicuticule percée par des «canalicules épicuticulaires». Une comparaison est établie avec la glande sternale d'autres termites, en particulier celle de Kalotermes.
    Notes: Summary The sternal gland of Trinervitermes geminatus appears as a median thickening of the epidermis at the anterior part of the fifth abdominal sternite. It is lined internally with a thin basal lamina and externally with the cuticle. A few campaniform sensilla are also visible in the glandular mass. Two types of cells may be recognized. First, oval-shaped cells, containing numerous large mitochondria and dense globules; these cells having no contact with the cuticle are connected with the basal lamina by a few narrow cytoplasmic stems. Second, tall columnar cells, with vesicular endoplasmic reticulum and an apical brush border built up by microvilli and finger—like processes which reach into the cuticle. This cuticle is made of alveolous mesocuticle and a thin epicuticle perforated by “epicuticular canals”. The organ is compared with the sternal gland of other termites, particularly with the one of Kalotermes.
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  • 34
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    Cell & tissue research 130 (1972), S. 553-574 
    ISSN: 1432-0878
    Keywords: Thyroid gland ; Xenopus laevis ; Iodine uptake ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Ziel dieser Untersuchung war eine physiologische Deutung der Ultrastruktur von Schilddrüsenepithelzellen bei Larven von Xenopus laevis. Dazu wurden elektronenmikroskopische Bilder mit morphometrischen Methoden quantitativ ausgewertet und die Ergebnisse mit Jodaufnahmedaten verglichen. So konnte die Aktivierung der Schilddrüse durch TSH bei kälteblockierten bzw. hypophysektomierten Tieren mit Veränderungen während der spontanen Metamorphose verglichen werden. Ihrer Ultrastruktur nach sind die Schilddrüsen blockierter Prometamorphoselarven in der Entwicklung auf ein früheres Stadium zurückversetzt. Auch zeigen hypophysektomierte Larven keine spontane Jodaufnahme. Eine einmalige TSH-Injektion läßt dann die Größe und Form der verschiedenen Organellen vorübergehend den Zustand der Kontrollen erreichen. Besonders rasch und stark sprechen einerseits die Kernstruktur, andererseits Mikrovilli und Kolloidtropfenvolumen, welche die Resorption von Thyreoglobulin charakterisieren, auf den TSH-Reiz an. Die Jodaufnahme verläuft langsamer. Auch reagieren die an der Synthese beteiligten Organellen später und schwächer. In der spontanen Metamorphose wachsen die Schilddrüsen, nach Totalvolumen, Cytoplasmavolumen einzelner Zellen und Epithelhöhe beurteilt, bis zum Ende der Metamorphose weiter und nehmen entsprechend mehr Jod auf. Ebenso wird während der ganzen Klimax die Kolloidresorption der einzelnen Zellen stärker. Aus den Ergebnissen wird geschlossen, daß die TSH-Sekretion schon in der Prometamorphose einsetzt und bis gegen Ende der Metamorphose zunimmt.
    Notes: Summary The epithelial cells of the thyroid gland in larvae of Xenopus laevis were investigated with the electron microscope. Morphometrical methods yielded quantitative data on the morphology. The uptake of radioactive iodine was studied in order to obtain information on the physiological activity. Thus changes in the thyroid gland following the injection of TSH in tadpoles which had been hypophysectomized or blocked at low temperature were compared with the development of glands during spontaneous metamorphosis. The thyroid glands of blocked prometamorphic larvae resemble those of younger developmental stages as judged by their ultrastructure. In addition no spontaneous accumulation of iodine is observed. Following an injection of TSH the morphology of the various organelles becomes temporarily identical to that of the controls. These changes are most prominent in the nucleus as well as in the microvilli and the colloid droplets, which characterize the resorption of thyroglobulin. Only a minor effect of the TSH stimulus is found on iodine uptake and on organelles concerned with protein synthesis. During normal metamorphosis an increase is observed in the following parameters: (1) volume of the thyroid gland, (2) volume of the cytoplasm and height of single epithelial cells, (3) resorption of colloid, (4) iodine uptake. This increase persists until the end of the climax. Based on the present results TSH secretion is assumed to start in early prometamorphosis and to rise up to the end of metamorphosis.
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  • 35
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    Cell & tissue research 131 (1972), S. 47-62 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Lungfish ; Ultrastructure ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The neurohypophysis of the South American lungfish Lepidosiren paradoxa has been studied with light and electron microscopy, including the Falck-Hillarp technique for catecholamines. The pars nervosa hypophyseos is a well-marked, dorsally located subdivision of the pituitary gland composed of lobes or follicles, each one constituted of a central core of ependymal cells, a subependymal hilar region made up of nerve fibers and a peripheric palisade zone of nerve endings which contact capillary vessels. Four types of neurosecretory axons can be distinguished under the electron microscope. Type I, the most common, contains spherical elementary granules of high electron density, 1500–1800 Å in diameter. The scarce type II axons contain irregularly-shaped elementary granules. Type III contains only small clear vesicles, 400–600 Å in diameter. Type IV, mostly present in regions of the gland contacting the pars intermedia, contain large granulated vesicles, 900–1000 Å in diameter. The Falck-Hillarp technique revealed axons with a positive reaction for catecholamines at sites corresponding approximately to the location of type IV of the electron microscope. Ependymal cells are of large size, linking the cerebrospinal fluid, the nerve endings and the blood vessels. A conspicuous membrane-bound, spherical dense material, 1400–2000 Å in diameter, is observed in both the apical and vascular processes of these cells. The ependymal processes which traverse the hilar and palisade regions contain structures resembling degenerated neurosecretory axons. These results are discussed in relation with the currently available information on the comparative anatomy of the pars nervosa. The possible functional significance of ependymal cells and of each type of axon are also discussed. This study was aided by the following grants: NIH NS 06953 to Prof. De Robertis, Consejo Nacional de Investigaciones Científicas y Técnicas to Prof. Zambrano, Comisión de Investigaciones Científicas de la Provincia de Buenos Aires and Comisión de Investigaciones Cientificas de la Universidad Nacional de la Plata: to Prof. Iturriza. The authors are indebted to Prof. De Robertis for his generosity in granting us his laboratory facilities, and to Dr. F. J. J. Risso and Mr. A. Fernández (Resistencia, Chaco) who provided the specimens used in this study. The able microtechnical assistance of Miss L. Riboldazzi and Mrs. R. Raña and the photographic work of Mr. A. Saenz are much appreciated.
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  • 36
    ISSN: 1432-0878
    Keywords: Islets of Langerhans ; Grass-snake ; Crystalline B-granules ; Ultrastructure ; Crystallography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Kristalline B-Granula im Pankreas der Ringelnatter besitzen die Form von Rhombendodekaedern (a ≈ 11 nm, kubisch-raumzentriertes Gitter). Diese Diagnose wird abgeleitet von den Ergebnissen der dreidimensionalen Rekonstruktion von Serienschnitten, der optischen Diffraktometrie und aus dem Vergleich mit Kristallmodellen. Die Bedeutung kristalliner B-Granula wird erörtert.
    Notes: Summary Crystalline B-granules of grass-snake islets of Langerhans have been shown to possess the shape of rhombic dodecahedra (a ≈ 11 nm, cubic body-centered lattice). Three-dimensional reconstructions from serial sections, optical diffractometry and comparison with crystal models were the techniques utilized. The significance of crystalline B-granules is discussed.
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  • 37
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    Cell & tissue research 132 (1972), S. 25-34 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Perivascular cells ; Neurosecretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The purpose of this study is to investigate the ultrastructural features of perivascular cells as found in the neural lobe of the hypophysis. In particular, an inquiry was made into the nature of the relationship of such cells to neurosecretory fibers and endings. The latter, in fact, are often invaginated within the perivascular cells and enveloped by their processes; furthermore, they often reveal a certain number of empty granules as well as characteristics of degenerative nature. In the course of this study the localization of the perivascular cells has been investigated as well as that of their processes within the extensive interlobular network typical of the hypophysial neural lobe of rodents. Based on the data gathered, the hypothesis is put forward that the perivascular cells play an important role in the turnover of neurosecretory endings, both under physiological and experimental conditions, contributing thereby to the release of post-hypophysial hormones.
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  • 38
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    Cell & tissue research 132 (1972), S. 35-49 
    ISSN: 1432-0878
    Keywords: Salivary glands ; Octopus ; Nerves ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Le canal salivaire contient dans sa paroi deux types de nerfs, moteurs et sécréteurs. Le diamètre des fibres nerveuses est en moyenne plus faible dans les nerfs moteurs, où il diminue encore en direction des glandes, tandis qu'au contraire celui des fibres sécrétrices augmente, accentuant ainsi les différences morphologiques entre les deux ners. Ces différences de calibre entre les fibres sont en rapport avec le nombre plus ou moins élevé des neurites qu'elles comportent, et dont les mésaxones ont des formes variées. Les caractères cytologiques des cellules satellites et des axones des deux types de nerfs sont comparables. Les axones contiennent des vésicules de types morphologiques très divers dont la signification est discutée.
    Notes: Summary Two types of nerves, motor and secretory, are found in the wall of the salivary duct. The average diameter of the motor fibers is smaller and decreases still more towards the glands, while on the contrary it increases for the secretory fibers. The disparity of diameter between the two types of fibers is due to the different number of neurites they contain, embedded in satellite cells with mesaxons of various forms. Axons and satellite cells have similar cytological features in the two types of nerves. Vesicles of several morphological types occur in the axons; their significance is discussed.
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  • 39
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    Cell & tissue research 133 (1972), S. 35-46 
    ISSN: 1432-0878
    Keywords: Ultrastructure ; Fowl ; Liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the liver parenchymal cell from immature pullets and from immature and young mature cockerels has been studied. The results demonstrated that the fowl's hepatocyte is structurally very similar to that of other birds and, in spite of certain morphological differences between the livers of birds and mammals, is also very similar in structure to the liver cell of mammals.
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  • 40
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    Cell & tissue research 133 (1972), S. 59-86 
    ISSN: 1432-0878
    Keywords: Compound eyes ; Coleoptera ; Ultrastructure ; Dark-light-adaptation ; Irregularities
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structures of the eyes of two Staphylinid beetles, one large (Creophilus erythrocephalus—18 mm in length) and one small (Sartallus signatus—3 mm in length), were compared. 1. The gross structure of the two eyes is the same: a) biconvex corneal lens, b) crystalline cone of “acone type”, c) narrow crystalline thread and thickening of cone cell extensions just above the rhabdom, d) seven retinula cells plus one basal cell, and e) almost the same corneal refractive index and optical properties of the corneal cuticle. Considerable differences exist in size, shape and arrangement of rhabdom, retinula cells and their axons. The smaller size of the eye of Sartallus is caused by reduction of number of facets rather than cell size, and, in fact, retinula cells and rhabdom have been found to be larger in the smaller beetle. 2. Structural changes during dark-light-adaptation affect crystalline cone, position of screening pigment and size of intercellular spaces between the retinula cells. In the dark-adapted state the cone retracts a little and the crystalline tract becomes wider. A thickening of cone cell extensions occurs just above the rhabdom. Screening pigment migrates to a more distal position and intercellular spaces between the retinula cells considerably increase in size as compared with the light-adapted eye. 3. Both eyes are rich in irregularities. An attempt to classify anomalies of compound eyes has been made. The number of cone cells and principal pigment cells varied, in some cases, from 1–5 and 0–3 respectively. Basal retinula cells did not always contribute to the rhabdom. 4. Interferometrical observations reveal the extreme optical homogeneity of the entire corneal cuticle of the eyes of both species. No layers of different refractive index or optical separation of adjacent ommatidia can be found. The refractive index of the cornea of Creophilus is 1.469; that of Sartallus is 1.488. 5. Functional consequences of the changes which occur during dark-light-adaptation are discussed. Exposure to intense light appears to cause a rapid aging of retinula cells, which is indicated by an increase of onion- and multivesicular bodies.
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  • 41
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    Cell & tissue research 135 (1972), S. 115-127 
    ISSN: 1432-0878
    Keywords: Oligodendroglia ; Monkey ; De-afferentation ; Ultrastructure ; Densebodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopical examination of the norma and de-afferented ‘laterall geniculate body’ of the monkey following paraformaldehyde-glutaraldehyde vascular perfusion revealed distinctive morphological features of different types of oligodendrocyte. These cells were normally situated as perineuronal satellites or in relation to axons and capillaries. A wide range of nuclear and cytoplasmic densities were displayed by both satellite and interfascicular oligodendrocytes. The following distinctive features for the identification of ligodendrocytes were utilised: the presence of large quantities of free ribosomes and ribosomal rosettes, microtubular profiles, dense marginal aggregation of nuclear chromatin together with light patches and numerous nuclear pores; but the absence of broad cytoplasmic processes, glycogen and gliofibrils. Circumferential perinuclear organization of the cytoplasmic organelles was typical of oligodendrocytes. Particular attention was paid to perineuronal satellite cells in view of the known transneuronal atrophy in the de-afferented geniculate body. Some cells having a nuclear pattern of oligodendrocytes but showing hyalinisation of perikaryon were seen in de-afferented laminae. A notable feature was the presence of variegated “osmiophilic bodies” in the perikaryon of oligodendrocytes also situated in the de-afferented laminae. A cell type combining the features of oligodendrocytes and astrocytes was classified as ‘intermediate neuroglia’.
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  • 42
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    Cell & tissue research 124 (1972), S. 454-464 
    ISSN: 1432-0878
    Keywords: Lateral-line organ ; Eel (Anguilla japonica) ; Mechanoreceptor ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The sensory epithelium of the lateral line organ of the common eel consists of two types of cells, (sensory and supporting). The sensory cell bears a kinocilium together with about 40 to 60 stereocilia on its surface. The kinocilium is situated either at rostral or at caudal margin of this cilial group. Such polarity of the cilial group of one cell is inverse to that of an adjacent cell. Two types of crystal-like inclusions exist in the sensory cells, consisting of granules 100 Å in diameter. Granules in one type are arranged regularly whereas those in the other rather irregularly. Two types of nerve endings exist at the base of sensory cells: one is predominant in number and contains few vesicles, accompanied by a dense spherical body surrounded by small vesicles in the sensory cell and the other is rare in number and contains many vesicles, accompanied by a small flat sac just beneath the plasma membrane of the sensory cell. The supporting cells contain numerous mitochondria, a well developed Golgi apparatus and rough-surfaced endoplasmic reticulum, and surround a sensory cell completely. Physiologic significance of some of these components is discussed.
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  • 43
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    Cell & tissue research 124 (1972), S. 465-478 
    ISSN: 1432-0878
    Keywords: Anterior pituitary ; Mouse ; in vitro ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Anterior pituitaries of mice were incubated for periods up to four hours in Krebs-Ringer bicarbonate glucose gassed with 95% O2∶5% CO2. The incubated explants survived and retained a fine structure that approximated the condition in situ. The few necrotic cells were sharply localized, and were found to be due to initial mechanical damage to the tissue. Some cells of the six granulated types exhibited slight but significant changes attributable to the liberation from the hypothalamic control: in LTH cells there was a release of preexisting granules and a development of cell organelles, whereas in other cell types there was an inhibition of release of granules and an enhanced digestion of the accumulated granules by the lysosomal system. Follicular cells responded uniquely to the changed environment by hypertrophy of the cytoplasm and were found to phagocytize cell debris. A part of non-epithelial elements of the gland showed a tendency to modulate cytologically.
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  • 44
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    Cell & tissue research 126 (1972), S. 157-181 
    ISSN: 1432-0878
    Keywords: Nerve degeneration ; Nerve regeneration ; Crayfish ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cut and crushed crayfish claw nerves were examined with the electron microscope at intervals up to 6 months after lesion. In sections 1 centimeter distal to the lesion there were no signs of degeneration among the giant motor axons even after many months. Swelling of glial wrappings was observed within 48 hours of nerve severance and was particularly notable in the innermost glial layer, the adaxonal layer. Golgi elements, rough endoplasmic reticulum, and mitochondria accumulated in the glia. These changes were perhaps indicative of a greater supportive role required by the severed axons. Regeneration from the proximal stumps of the giant axons began within one week and had proceeded across the lesion gap by 4 weeks. Axon sprouts appeared to travel toward the terminals within the glial sheaths of the distal giant axon segments. Before regeneration was complete, as determined by a simple behaviour test, the regenerating axons occupied increasing proportions of the sheath space. After regeneration was complete occasional degenerations were seen among the sprouts. These degenerations may have occurred in regenerating axons which had grown to the incorrect muscles. The original distal giant axons probably degenerated, as well, after regeneration was complete. There was no evidence of rehealing of proximal and distal segments of the axons.
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  • 45
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    Cell & tissue research 126 (1972), S. 320-334 
    ISSN: 1432-0878
    Keywords: Glandulae submaxillares ; Mammals ; Acinar cell granules ; Ultrastructure ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Granules in acinar cells show considerable variations in size, shape, electron-density and molecular organisation of secretory material. Discrete organelles with an electron-dense homogenous matrix are seen in the guinea-pig and to some extent in the male hamster. Similar organelles with moderate electron-density are seen in the cat and dog. Acinar cells of the cat, hamster, guinea-pig and to a lesser extent the rat, contain discrete, pale granules and also confluent organelles arising from two to three of the pale particles. Composite, electron-pale secretory units are observed in the dog and rabbit. No correlation could be elicited between the histochemical reactivity of the acinar cells and the content of the secretory enzymes. The relationship between the histochemical reactivity and ultrastructural appearance of acinar cell granules and the organelles containing kallikrein, trypsin-like proteases and amylase seems much more important and functionally relevant. Morphological aspects of the intracellular transport and secretion of granules are discussed.
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  • 46
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    Cell & tissue research 126 (1972), S. 335-347 
    ISSN: 1432-0878
    Keywords: Glandulae submaxillares ; Mammals ; Duct cell granules ; Ultrastructure ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Discrete, PAS-positive granules of relatively uniform electron-density and size characterise the intercalated duct cells of mammalian submaxillary glands. Smaller, electron-dense organelles are seen in the cells at the junction of the intercalary-striated duct region in the guinea-pig. The large granules of variable electron-density which are observed in the proximal, modified intercalary cells in the rabbit closely resemble the granules in the acinar cells of the guinea-pig. Several populations of granules differing in size are found in the striated granular tubules of the rat and hamster; the organelles in the rat show two grades of electron-density whereas those in the hamster are uniformly dense. Numerous small granules with compactly arranged intragranular material occupy the apical part of the striated ducts of the cat, dog and rabbit. The chemical composition of each population of duct cell granules is unknown. The question whether granules containing kallikrein, trypsin-like enzymes and amylase are stored in the duct cells is discussed.
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  • 47
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    Cell & tissue research 126 (1972), S. 437-445 
    ISSN: 1432-0878
    Keywords: Eye ; Sarcophaga bullata ; Ommatidia ; Lamina ganglionaris ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary External and internal surfaces of the compound eye of the flesh fly, Sarcophaga bullata, were examined with a scanning electron microscope. A low patterned corneal nippleridge array and sparse setiform interfacetal hairs were observed on the corneal lens surface. Particular cleavage planes revealed outlines of the Semper Cells, their nuclei and distal terminations of photoreceptor cells. The latter, with their axonal processes, were visualized and described. These axons were noted traversing the external chiasma and entering the lamina ganglionaris where suggestions of synaptic contact were pointed out. The present descriptions were correlated with those taken from literature of the transmission electron microscope.
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  • 48
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    Cell & tissue research 127 (1972), S. 34-49 
    ISSN: 1432-0878
    Keywords: Cephalic kidney insects ; Diplura ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'ultrastructure du rein labial céphalique deCampodea chardardi Condé a été étudiée. Cette néphridie comprend trois parties: le saccule terminal, le labyrinthe et le canal excréteur. Les cellules du saccule sont des podocytes typiques, contenant de nombreuses vacuoles de pinocytose et des inclusions diverses. La lumière est envahie par des micro-organismes bacilliformes. Le labyrinthe possède des cellules à indentations basales profondes avec de nombreuses mitochondries, et des microvilli distaux. Le canal excréteur débouchant sur la face ventrale du labium est caractérisé par la présence d'une intima cuticulaire. Le rein labial des Diploures a été comparé avec des organes segmentaires néphridiens d'autres Arthropodes, et avec le néphron des Vertébrés.
    Notes: Summary The ultrastructure of the cephalic labial kidney ofCampodea chardardi Condé has been studied. Each nephridium is subdivided into three segments: end-sac, coiled tubule and efferent-duct. The cells of the sacculus are typical podocytes, and contain numerous pinocytotic vesicles and various vacuoles. The lumen contains micro-organisms. The cells of the coiled tubule bear basal infoldings with numerous mitochondria and distal microvilli. The efferent duct terminates close to the ventral face of labium, and possesses characteristic cuticular intima. The labial kidney of Diplura is compared with published data on the nephridial organs of other Arthropods and Vertebrate nephron.
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  • 49
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    Cell & tissue research 127 (1972), S. 201-208 
    ISSN: 1432-0878
    Keywords: Spermatogenesis ; Rat ; Mitosis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pattern of intercellular cytoplasmic bridges between rat spermatogonia and between spermatocytes is illustrated from electron microscopy of serial sections. Clones, or syncytia, containing as many as 22 connected spermatogonia and as many as 74 connected spermatocytes were observed. The absence of closed rings of cells agrees with the observation that intercellular bridges are the result of incomplete cell division, rather than cell fusion. The bridges thus are a record of spermatogonial divisions within a clone. In early spermatogonial generations there is a predominantly linear arrangement. The groups of spermatocytes have more side branches. From the presence of synaptonemal complexes it is concluded that the connected spermatocytes of a given clone are in about the same developmental stage. The pattern of intercellular bridges indicates, however, that not all nuclei in a clone undergo mitosis in the same cycle. The connected cells of a clone are therefore not all of the same generation. From unconnected bridges it is assumed that new clones originate from single cells or groups of spermatogonia which separate from an existing clone.
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  • 50
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    Cell & tissue research 124 (1972), S. 275-292 
    ISSN: 1432-0878
    Keywords: Sensory receptors ; Acarina ; Amblyomma americanum ; Haller's organ ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Hallersche Organ auf dem Tarsus der Zecke Amblyomma americanum (L.) (Acarina: Ixodidae; Nymphenstadium) wurde mit dem Durchstrahlungs- und Rasterelektronenmikroskop untersucht. Es besteht aus einer distalen Sensillengruppe, die in einer flachen „Wanne“ gelegen ist, und einer proximalen „Kapsel“, welche mehrere Sensillen einschließt. Alle sieben Sensillen der „Wanne“ (A1–A7) sind dickwandig und mehrfach innerviert (2–9 Neurone), jedoch können mindestens 3 verschiedene Typen unterschieden werden: A1 und A2 besitzen große Poren (〉1000 Å), die mit Pfropfen versehen sind, und sie sind zudem die einzigen Sensillen mit sich verzweigenden Dendriten; A3 und A5 sind durch eine radspeichenartige Anordnung der Cuticulawandung charakterisiert, ferner durch feine Poren (100–200 Å), welche die Speichen zentral durchziehen; A4, A6, und A7 zeigen kein Porensystem, doch wird eine einzelne Öffnung an der Spitze vermutet. Die „Kapsel“ enthält 7 dünnwandige, stumpf endigende Sensillen und mehrere nichtsensorische Cuticulavorsprünge. Alle Sensillen besitzen große „Pfropfporen“ in der Cuticulawandung und zahlreiche dendritische Verzweigungen mehrerer Neuronen (3–5) im Lumen. Drüsenmündungen wurden in der „Kapsel“ festgestellt, ihre Bedeutung wird diskutiert. Die Feinstruktur des Hallerschen Organs entspricht dem Postulat von Lees (1948), wonach die „Kapsel“ der Geruchsrezeption, die „Wanne“ der Feuchtigkeitsrezeption dienen soll.
    Notes: Summary Haller's organ on the tarsus of the tick Amblyomma americanum (L.) (Acarina: Ixodidae; nymphal stage) was studied by scanning and transmission electron microscopy. It consists of a distal bristle group, (the “anterior pit”), and a proximal “capsule” which encloses several sensilla. The seven sensilla of the anterior pit (A1–A7) are all thick-walled and multi-innervated (2–9 neurons), but at least three different types can be differentiated. Sensilla A1 and A2 possess large, plugged pores (〉1000 Å) and are the only sensilla with branching dendrites. A3 and A5 are characterized by a spoke-wheel arrangement of the cuticle wall and very fine pores (100–200 Å) penetrating the “spokes” centrally; A4, A6, and A7 do not exhibit any pore system but a single opening at the bristle tip is assumed. The capsule contains seven thin-walled, blunt-tipped sensilla, and several non-sensory cuticular projections (pleomorphs). All of these sensilla possess large “plugged” pores in the cuticle wall and numerous dendritic branches of several neurons (3–5) in the lumen. Glandular openings were found inside the capsule; their significance is discussed. The fine structure of Haller's organ supports the functions postulated by Lees (1948), namely olfaction for the capsule and humidity reception (among others) for the anterior pit.
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  • 51
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    Cell & tissue research 124 (1972), S. 520-531 
    ISSN: 1432-0878
    Keywords: Mitochondria ; Cytomembranes ; Oocyte ; Pig ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An ultrastructural study of the mature follicular oocytes in domestic pig demonstrate a morphological relationship between the mitochondria and the cytoplasmic membranes immediately surrounding the yolk globules of the cells. Frequently, the cytoplasmic membranes are observed to be in close proximity of the mitochondria or are found to be continuous with the outer mitochondrial membrane. Sometimes the cytoplasmic membranes are found to display the formation of one or more oval loops of different diameter located at their presumed ends or free in the nearby cytoplasm. The significance of these observations is discussed in the light of the available informations, which suggest that the cytomembrane system in certain phases of development may take part in the formation of mitochondria.
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  • 52
    ISSN: 1432-0878
    Keywords: Epithelial cells ; Echinoderm ; Asterina gibbosa ; Regeneration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'évolution ultrastructurale de la cellule neuroépithéliale a été faite, chez Asterina gibbosa, au cours de la régénération du bras. La dédifférenciation de la cellule, provoquée par l'amputation, se manifeste par la perte de sa partie apicale et la régression des structures cytoplasmiques: vésiculisation du Golgi et de l'ergastoplasme, fragmentation des microtubules. L'activation qui accompagne la dédifférenciation, se manifeste par la formation d'un nucléole au centre du noyau. Elle correspond à la reprise des synthèses d'ARN. La cellule dédifférenciée est caractérisée par un nucléole excentré et l'abondance des ribosomes libres. La différenciation débute par le regroupement en rosettes des ribosomes et le développement des canalicules ergastoplasmiques. Le Golgi réapparaît au voisinage du noyau. Les mitochondries se disposent aux pôles basal et apical de la cellule, où les microtubules se reconstitutent. En fin de différenciation, les cellules se réorganisent pour édifier un épithélium cicatriciel limité par une basale. Le tissu épidermique se différencie à partir des éléments de même origine sans l'intervention de cellules souches.
    Notes: Summary The ultrastructural differentiation of the neuroepithelial cell in the course of regeneration in Asterina gibbosa has been investigated up. Cell differentiation, induced by cutting the arm off, is characterized by loss of the apical cell pole and alteration of cytoplasmic structures: vesiculation of the Golgi apparatus and the ergastoplasm, fragmentation of microtubules. Activation, which parallels dedifferentiation, induces the appearance of a nucleolus in the center of the nucleus. This means that RNA synthesis is starting again. A dedifferentiated cell shows an eccentric nucleolus and many free ribosomes. Differentiation beginning, clusters of ribosomes and the development of tubular ergastoplasmic formations can be observed. The Golgi apparatus is located near the nucleus. Mitochondria gather at basal and apical part of the cell, where also microtubules are forming again. In the last stage of differentiation, cells are joining up and build a scar epithelium resting on a basement membrane. Epidermic tissue differentiates only from epidermic cells. Blast cells have no part in this process.
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  • 53
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    Cell & tissue research 128 (1972), S. 1-18 
    ISSN: 1432-0878
    Keywords: Muscle ; Slow ; Denervation ; Structure ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The slow anterior latissimus dorsi muscle (ALD) of the pigeon was denervated surgically and examined after varying post-operative intervals. Muscles were studied with respect to changes in weight, histological and ultrastructural alterations, and changes in size and number of fibers. The weights of the denervated muscles increased over the contralateral control, reaching a maximum hypertrophy in the first 18 days, but the hypertrophy persisted for several months. The fibers of the denervated muscle did not hypertrophy. They showed a gradation in size from the posterior to the anterior border, with the fibers in the anterior third of the muscle being the smallest. After measuring cross-sectional sizes from the anterior, middle, and posterior thirds of the muscle, the overall fiber change was one of atrophy. Morphologically, the fibers showed various signs of pathological changes, including nuclear proliferation, swelling and migration away from the sarcolemmal position, vacuolation, myofibril degeneration, connective-tissue infiltration and replacement of the fibers, and regenerative activities in the form of budding and myoblast formation. A condition termed a peripheral rim of degeneration is described. Although many abnormal conditions were found in these denervated muscles, much of the muscle appeared normal; the neurotrophic relationship of slow muscle is discussed.
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  • 54
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    Cell & tissue research 128 (1972), S. 283-302 
    ISSN: 1432-0878
    Keywords: Human placenta ; Langhans cells ; Syncytiotrophoblast ; Regeneration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Langhanszellen in menschlichen Placentazotten werden nach ultrastrukturellen Kriterien in undifferenzierte, wenig differenzierte, mäßig differenzierte, syncytiumähnliche und degenerierende Formen unterteilt. Im Laufe der Schwangerschaft vermehren sich die undifferenzierten und die syncytiumähnlichen Zellen zu Ungunsten der mäßig differenzierten. Die in der 9. Woche fast vollständige Cytotrophoblastlage wird in der reifen Placenta auf etwa 20% der Oberfläche reduziert; die verbliebenen Zellen liegen überwiegend in Kapillarnähe. In chronisch mangelernährten Placenten ist die Zahl der Langhanszellen größer, ihr Cytoplasma ist dichter und organellenreicher. In den schwersten Fällen geht das Syncytium zugrunde, und Langhanszellen grenzen an den intervillösen Raum. Vergleiche histochemischer, experimenteller und klinischer Befunde ergeben, daß die Teilungstendenz der Langhanszellen bei guter Versorgungslage gering ist. Da die syncytiale Verschmelzung unter diesen Bedingungen leicht ist, nimmt die Zellzahl ab. Bei chronischer Ischaemie der Zotten dagegen nimmt die Proliferations- und Differenzierungstendenz des Cytotrophoblasten zu. Bei erschwerter syncytialer Verschmelzung steigt die absolute Umwandlungsrate an. Es gelangen damit vermehrt neugebildete hochaktive Enzymsysteme in den Syncytiotrophoblasten. Dieses Verhalten bedingt die Bedeutung der Langhanszellen als Teil eines Regelkreises zur Regeneration des Syncytiums unter normalen und unter pathologischen Bedingungen.
    Notes: Summary The Langhans cells in human placental villi are subdivided according to ultrastructural criteria into undifferentiated, poorly differentiated, moderately differentiated, syncytium-resembling and degenerated forms. In the course of pregnancy the undifferentiated and the syncytium-resembling cells increase to the debit of the poorly differentiated. The cytotrophoblastic layer which is almost complete at the 9th week of gestation is reduced in the mature placenta to about 20% of the total surface area; the remaining cells are situated mainly near the capillaries. In chronically undernourished placentae the number of Langhans cells is increased; their cytoplasm is denser and contains more organelles. In the most severe cases the syncytium becomes necrotic and Langhans cells lie at the intervillous space. Comparisons of histochemical, experimental and clinical findings show that the tendency of the Langhans cells to proliferate is small if the placenta is well supplied. Since the syncytial fusion is easy under these conditions the cell number declines. In chronic ischemia of the villi, however, the tendency of the cytotrophoblast to proliferate and differentiate increases. Though the syncytial fusion is moderately aggravated the absolute rate of transformation increases. Therefore more newly formed, highly active enzymatic systems reach the syncytiotrophoblast. This mode of action shows the importance of the Langhans cells as a part of a feed back system for the regeneration of the syncytium under normal and pathological conditions.
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  • 55
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    Cell & tissue research 131 (1972), S. 429-436 
    ISSN: 1432-0878
    Keywords: Hormone granules ; Thyroid (C-cells) ; Anterior Pituitary ; Ultrastructure ; Freeze-etching method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Gefriergebrochene Präparate (mit und ohne Ätzung) der Adenohypophyse und der C-Zellen der Schilddrüse von Ratte und Meerschweinchen wurden elektronenmikroskopisch untersucht. Bei den Hormongranula dieser Zellen verlaufen die Bruchflächen im allgemeinen zwischen den beiden Membranflächen oder zwischen Granulum-Inhalt und Membran. Nur relativ selten werden Granula quergebrochen. Auf beiden Hälften der gespaltenen Membranen der C-Zellgranula werden etwa mit gleicher Häufigkeit Proteinpartikel (100–200 Å) gefunden. Bei den Granula der somatotropen Zellen treten auf der dem Plasma anliegenden Membranhälfte deutlich mehr Proteinpartikel auf als auf der dem Granuluminhalt anliegenden Hälfte. Der Inhalt der somatotropen und C-Zellgranula erscheint bei dieser Präparationsmethode aus einer dichten Packung von 80–100 Å großen Partikeln zu bestehen. Eine besonders strukturierte Zone zwischen Membran und Granuluminhalt konnte bei den bisherigen Untersuchungen nicht festgestellt werden. Durch Ätzung der Gefrierbrüche ließen sich keine zusätzlichen strukturellen Details der Granula darstellen. Eine durch Auswertung von stereoskopischen Aufnahmen gewonnene Größenverteilungskurve für die C-Zellgranula wird vorgelegt.
    Notes: Summary Freeze-fractured preparations (with and without etching procedures) of guineapig and rat thyroid (C-) cells and anterior pituitary (somatotropic-) cells have been investigated with the electron microscope. The hormone granules of these cells in general split either between the two lamellae of their unit membrane or between the granule contents and the unit membrane. Only rarely cross-broken granules have been observed. Inner and outer lamella of the unit membrane of the C-cell granules contain in more or less similar frequency moderate amounts of protein particles of 100–200 Å diameter. In case of the somatotrophs the outer lamella contains higher numbers of these particles than the inner one. The contents of the C-cell and somatotroph granules seems to consist of densely packed 80–100 Å particles. A particular zone between contents and membrane (as observed on micrographs with conventional electron microscopy) could not be detected on freeze-fractured preparations. The etching procedure does not reveal additional details of the granule structure. A size distribution curve of the C-cell granules as determined from stereo-pairs, is given.
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    Cell & tissue research 131 (1972), S. 497-517 
    ISSN: 1432-0878
    Keywords: Granulosa cells ; Oocyte ; Pig ; Mitochondria ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pig oocytes and their surrounding granulosa cells obtained from mature Graafian follicles at a stipulated time near to ovulation were studied in some details electronmicroscopically. Particular emphasis is given to the corona radiata cell processes and to the heterogeneous population of mitochondria in the oocyte. The corona radiata cell processes contain various components such as filaments, mitochondria, multivesicular bodies and lipid droplets in their matrix. The contact relationship of the corona radiata cell processes to the oocytes is maintained by desmosomes. Usually, the two parallel surface membranes forming the desmosome are separated by a space of about 200 Å. Occasionally, the two membranes approximate each other to form a junction having a “gap” of about 70 Å. Apparently the membranes become fused in some regions. Of particular interest is the distribution and structural characteristics of the single-membrane-bounded structures, and their relationship to the cytomembranes and the mitochondria. On the basis of the present and earlier (Norberg, 1972) observations, the question arises whether the formation and development of mitochondria of pig oocytes depend, at least partly, on a metamorphosis of single-membrane-bounded structures derived from less complex membraneous elements. Final conclusions concerning this problem demand integrated morphological and biochemical investigation regarding the biosynthesis of mitochondria.
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  • 57
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    Cell & tissue research 131 (1972), S. 545-557 
    ISSN: 1432-0878
    Keywords: Pars intermedia ; Hypothalamus ; Anurans ; Hormone release ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the pars intermedia of Rana catesbeiana tadpoles was studied following isolation from the hypothalamus, in vivo after sectioning of the pituitary stalk, and in vitro after implantation of the pituitary into a piece of tail fin. Both experimental procedures were followed by rapid and sustained skin darkening. Pituitaries from normal light and dark adapted tadpoles served as controls. In 4-hour disinhibited glands, melanotrophs revealed hyperactive Golgi bodies, colloid vesicles (1–2 microns) in close proximity to axon terminals, and no apparent loss of secretory granules. At 24 hours extracellular colloid adjacent to axon terminals was found, and extensive arrays of RER appeared in the melanotrophs. Obvious granule loss from secretory cells occurred within a week, by which time the cytoplasm was occupied by large cisterns of SER and RER and abundant free ribosomes. Dense core vesicles (600–900 Å) in aminergic nerve terminals disappeared shortly after isolation of the pituitary from the hypothalamus, and only decreasing numbers of translucent vesicles (200–300 Å) were found. The functional significance of these changes is discussed, with particular emphasis on the mode of acute hormone release.
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    Cell & tissue research 132 (1972), S. 15-24 
    ISSN: 1432-0878
    Keywords: Digestive diverticula ; Bivalves ; Peroxisomes ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopy of the digestive diverticula of the protobranch bivalve, Nucula sulcata, revealed the presence of peroxisomes in the basal regions of the epithelial cells lining the main and secondary ducts, and in the digestive and secretory (basophil) cells of the tubules. Those in the secretory cells are elongate and somewhat flattened, while those of the other cell types have a spherical form. Two distinct types of nucleoid are normally present within the secretory cell peroxisomes, one compact, crystalline, and finely polytubular, the other comprising isolated secondary tubules arranged in a linear series across the width of the organelle. The peroxisomes of the digestive and duct cells contain coarsely polytubular cores arranged in two clusters orientated more or less at right angles; the duct cell peroxisomes may also contain a second nucleoid in the form of a compact finely polytubular core. Sections incubated in a medium containing 3,3'-diaminobenzidine (DAB) and hydrogen peroxide reveal an electron dense reaction product within the peroxisomes of all the cell types. Catalase is considered to be responsible for the reaction.
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  • 59
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    Cell & tissue research 132 (1972), S. 51-65 
    ISSN: 1432-0878
    Keywords: Salivary glands ; Octopus ; Innervation of musculature ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les fibres nerveuses, souvent composées, qu'on peut trouver dans le tissu conjonctif séparant les fibres musculaires du canal, ou les tubules de la glande, sont très comparables morphologiquement aux fibres des troncs moteurs. Leurs cellules satellites, qui contiennent de grosses inclusions, nombreuses et très denses aux électrons, engainent les axones pratiquement jusqu'au niveau des terminaisons. Les jonctions neuromusculaires sont caractérisées par l'accumulation de petites vésicules claires, accompagnées de quelques vésicules plus grandes et à »coeur« dense. Les axones présentent aussi le long de leur trajet des segments plus ou moins dilatés où existent des vésicules de types très variés, et dont la signification est discutée.
    Notes: Summary Nervous fibers, often composite, can be found in the connective tissue between the duct muscular fibers, or the gland tubules. They are morphologically similar to the motor trunks fibers. Their satellite cells, containing numerous electron-opaque large inclusions, can be seen round the axons nearly to the nerve endings. Neuromuscular junctions are characterized by the accumulation of small clear vesicles, intermingled with some larger dense-cored vesicles. Axonal swellings, with numerous vesicles of various types, can also be seen along the course of the nerve fibers; their significance is discussed.
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    Cell & tissue research 132 (1972), S. 131-146 
    ISSN: 1432-0878
    Keywords: Nervous tissue ; Tardigrada ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Nervengewebe von Macrobiotus hufelandi zeichnet sich durch stark verzweigte pseudunipolare Nervenzellen und relativ wenige Gliazellen aus. Die Neurone besitzen rauhes ER, freie Ribosomen, zahlreiche Mitochondrien, einen wenig ausgeprägten Golgi-Apparat und einen elektronenlichten Kern. In ihren Axonen finden sich Vesikel und Einschlüsse unterschiedlicher Größe und Zusammensetzung. Die Gliazellen verzweigen sich stark und besitzen glattes ER, viele freie Ribosomen und einen elektronendichten Kern. Ganglien und Nerven werden nur durch eine dünne Neurallamelle vom extraganglionären Raum getrennt. Die morphologische Ausbildung des Nervengewebes wird im Hinblick auf die extreme Lebensweise der Tardigraden diskutiert.
    Notes: Summary The typical elements of the nervous tissue of Macrobiotus hufelandi are strongly ramified pseudunipolar neurons and a small amount of glial cells. In the perikarya of neurons there are rough ER, free ribosomes, many mitochondria, a poor Golgi-apparatus, and an electron-light nucleus. Nerve fibers contain masses of vesicles and inclusions of different size and composition. The ramifying glial cells have smooth ER, many free ribosomes, and an electron-dense nucleus. Ganglia and nerves are separated from the extraganglionic cavity by a thin acellular sheath (neural lamella). The organization of the nervous tissue is discussed with regard to the extreme conditions of environment of the tardigrades.
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    Cell & tissue research 132 (1972), S. 193-201 
    ISSN: 1432-0878
    Keywords: Branchial glands ; Cephalopods ; Haemocyanin synthesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The paired branchial glands in cephalopods are essential for life. The electron microscope reveals them to consist of cells containing masses of endoplasmic reticulum organised in parallel arrays together with pale areas between the reticulum that contain vacuoles. All three regions of the cells contain masses of haemocyanin particles and it is suggested that the gland is the site of haemocyanin synthesis, the particles being made amongst the endoplasmic reticulum at discharged into the pale areas and vacuoles before being released into the general circulation.
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  • 62
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    Cell & tissue research 132 (1972), S. 451-472 
    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Myxine glutinosa ; Cell types ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of adenohypophysial cells in the Atlantic hagfish (Myxine glutinosa) is described and the morphological evidence for secretory activity is discussed. A scarcity of secretory granules is characteristic of the adenohypophysis of Myxine. Two cell types having the appearance of protein hormone producing cells can be identified. Type 1 has dense membrane-bound granules with a calculated mean diameter of 88 nm while type 2 has larger granules with a mean diameter of 176 nm. The release of secretory granular material follows mainly the “membrane-release” pattern. It is suggested that cell type 1 may produce a hormone which is similar to ACTH/MSH and type 2 another hormone similar to STH/LTH. The basophilic cells contain a secretory material which is similar to the mucus produced in the epithelial mucus cells. Several structural modifications are considered to represent functional compensations for the absence of vascular elements in the gland. Among these are a cytoplasmic tubular system, certain long agranular cells together with long granule-containing projections from cell types 1 and 2, and foliate or finger-like invaginations of the basal lamina.
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    Cell & tissue research 133 (1972), S. 47-57 
    ISSN: 1432-0878
    Keywords: Endometrium ; Human ; Granular stroma cells ; Relaxin ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'ultrastructure générale des cellules K endométriales est semblable chez l'Homme, le Rat et le Singe. Mais les granulations des cellules K humaines sont plus variées que dans ces deux dernières espèces et ont certains aspects suggérant une fonction catabolique. Etant donné cet aspect catabolique et l'existence connue d'une activité phosphatasique acide de ces cellules contenant de la relaxine, les auteurs suggèrent que les cellules K pourraient être des cellules sécrétantes en involution et ques les cellules sécrétant activement la relaxine pourraient avoir un aspect morphologique quelque peu différent de celui des cellules K.
    Notes: Summary The general ultrastructure of endometrial granular stroma cells is similar in man, rat, and monkey. But the granulations of human granular stroma cells are more various than in these two last species and have some aspects suggesting a catabolic function. With respect to this catabolic aspect and the previously shown acid-phosphatase activity of these relaxin-containing cells the authors suggest that the granular stroma cells could be involutive secretory cells and that the active relaxin-secretory cells may have some different morphological aspect.
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    Cell & tissue research 133 (1972), S. 277-288 
    ISSN: 1432-0878
    Keywords: Flatworm ; Muscle ; Neuromuscular junction ; Sarcoplasm ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neuromuscular junctions in the marine polyclad flatworm, Notoplana acticola were studied with the electron microscope. Synapses were found between nerve endings and specialized extensions of the muscle cells. Characteristically these processes contained clear cytoplasm with a basal mitochondrion and numerous microtubules aligned parallel to the long axis of the extension. Sarcoplasmic diverticuli which contained the nucleus had granular cytoplasm with an assortment of membranes and organelles. We have proposed the term sarconeural junction to describe synapses between long sarcoplasmic extensions and nerve cells in flatworms as well as other animals. Tight junctions between adjacent contractile portions of muscle cells were common. As groups of cells appeared to be connected by tight junctions or shared common nerve terminals we conjectured that these formed discrete functional motor-units.
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    Cell & tissue research 134 (1972), S. 255-271 
    ISSN: 1432-0878
    Keywords: Hepatopancreas ; Limulus ; Gap junctions ; Calcium spherules ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the hepatopancreas and associated tissues of Limulus is described. All hepatopancreatic tubules contain L- and D-cells. L-cells exhibit apical pinocytosis and contain many different types of inclusions, including lipid containing calcium spherules of unique structure. They also produce a complex secretory product released by apocrine secretion. D-cells contain much rough endoplasmic reticulum, and show other evidence of active protein synthesis. They produce a single type of secretory granule released by merocrine activity. The appearance of L- and D-cells in tubules of various sizes and in fed and starved animals is described. Both cell types may produce digestive enzymes and absorb and transport nutrients to the hemolymph, but neither serves as a major storage site. Storage is an important function of the intertubular R-cells. The appearance of R-cells in fed and starved animals is described. A previously undescribed hemocyte is reported, as are apparent gap junctions between L- and R-cells. A structural and functional comparison of these glands with those of other arthropods is presented.
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    Cell & tissue research 125 (1972), S. 143-175 
    ISSN: 1432-0878
    Keywords: Skin ; Cephalopods ; Chromatophores ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Rapid, physiological color changes seen in the skin of cephalopods are due to a unique anatomical system composed of chromatophore organs and iridophores. The morphology and ultrastructure of the chromatophores was studied in the squids Loligo pealii Lesueur and Loligo opalescens Berry. A three-dimensional model of a brown chromatophore was reconstructed from serial sections for the electron microscope. The chromatophore organ is composed of a central nucleated pigment cell, 10–30 obliquely striated muscle cells (radially arranged on the equator of the pigment cell), axons, Schwann cells, and sheath cells. The pigment cell consists of a central aggregation of pigment granules and surrounding peripheral cytoplasmic compartments. These regions are incompletely separated by an electron-dense, sac-like structure, the pigment container. Proximal portions of a muscle cell contact the pigment cell in regions called myo-chromatophore junctions. Neuromuscular and myo-muscular junctions are also present. The results presented are discussed in terms of previous morphological and physiological studies of chromatophores.
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    Cell & tissue research 125 (1972), S. 176-190 
    ISSN: 1432-0878
    Keywords: Skin ; Cephalopods ; Iridophores ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Two populations of iridophores are responsible for the iridescent color of the squids Loligo pealii and Loligo opalescens. The superficial group, the short iridophores, underlie the chromatophores and are associated with muscle cells of the skin. The long iridophores, a deeper-lying group, are arranged in a dense sheet. The ultrastructure of iridophores was described, including iridosomes, iridosomal platelets and iridosomal tubules. The observations were discussed in terms of adaptive coloration in these animals.
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  • 68
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    Cell & tissue research 124 (1972), S. 39-43 
    ISSN: 1432-0878
    Keywords: Ruminal epithelium ; Zonulae occludentes ; Goat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Pansenepithel besitzt in den tiefen Hornzellen, die an das Stratum granulosum grenzen, eine Barriere. Diese Barriere, die das Labyrinth der Interzellularräume gegen das Pansenlumen verschließt, ist mit Zonulae occludentes ausgestattet.
    Notes: Summary The deep horn cells of the goat ruminal epithelium, which border the stratum granulosum, form an important component of the epithelial barrier. This barrier of the intercellular labyrinth presents zonulae occludentes (tight junctions).
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  • 69
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    Cell & tissue research 124 (1972), S. 39-43 
    ISSN: 1432-0878
    Keywords: Ruminal epithelium ; Zonulae occludentes ; Goat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Pansenepithel besitzt in den tiefen Hornzellen, die an das Stratum granulosum grenzen, eine Barriere. Diese Barriere, die das Labyrinth der Interzellularräume gegen das Pansenlumen verschließt, ist mit Zonulae occludentes ausgestattet.
    Notes: Summary The deep horn cells of the goat ruminal epithelium, which border the stratum granulosum, form an important component of the epithelial barrier. This barrier of the intercellular labyrinth presents zonulae occludentes (tight junctions).
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  • 70
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    Cell & tissue research 124 (1972), S. 311-319 
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Neurovascular contacts ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the median eminence of the rat axons of the supraoptic-paraventricular-hypophyseal tract with elementary neurosecretory granules (150–200 mμ) traverse the internal zone. Terminals containing dense core vesicles 60–120 mμ in diameter end on the portal capillaries of the median eminence. A unique organisation of the primary portal capillaries is shown. Endothelial cells have many fenestrae. The pericapillary space has numerous extensions all of which represent a special zone around the endothelial tube. The fine structural organisation and function of the neurovascular contacts in the median eminence are discussed.
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  • 71
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    Cell & tissue research 127 (1972), S. 356-373 
    ISSN: 1432-0878
    Keywords: Complex eye ; Formica polyctena ; Receptors ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Analyse der Feinstruktur des Komplexauges der Ameise Formica polyctena ergab, daß der dioptrische Apparat der insgesamt 750 Ommatidien aus einer lamellierten Cornealinse und einem euconen Kristallkegel besteht. Zwei Hauptpigmentzellen umgeben schalenförmig den Kristallkegel, 8 Nebenpigmentzellen schirmen das Ommatidium in seiner ganzen Länge von der Cornea bis zur Basalmembran ab. Jedes Ommatidium besteht in seinem distalen Teil aus 8 Retinulazellen, 2 gegenüberliegenden schmalen und je 3 gegenüberliegenden großen Sehzellen. Weiter proximal tritt eine 9. Retinulazelle hinzu. Die Mikrovillisäume der Sehzellen verschmelzen zu einem zentralen Rhabdom. Im distalen Teil sind die Mikrovilli in 3 Richtungen angeordnet. Es wird im besonderen die Orientierung der Mikrovilli zur Augenlängsachse und zur Ommatidien-Symmetrieachse untersucht. Auch die 9. Sehzelle bildet Mikrovilli. Das Rhabdom endet an 4 basalen Pigmentzellen. Auf den Mikrovillisaum folgt im Querschnitt des dunkel adaptierten Ommatidiums ein Kranz von großen intrazellulären Vakuolen. Die anschließende cytoplasmatische Zone der Retinulazellen enthält viele Pigmentgranula und Mitochondrien; multivesikuläre und multilamelläre Körper sowie Golgiapparate treten nur selten auf. Die funktionelle Bedeutung des Ommatidienaufbaues und die Verteilung der Organellen bei Dunkeladaptation werden diskutiert.
    Notes: Summary The fine structure of the compound eye of the ant Formica polyctena was investigated. The eye consists of a total of 750 ommatidia, each containing a dioptric apparatus of a lamellated cornea lens, a eucone-type crystalline cone, and 8 long pigment cells which surround the ommatidium for its total length, i.e. from the cornea to the basal membrane. Each ommatidium has in its distal portion 8 retinula cells—6 large plus 2 small ones. The retinula cells are arranged in such a way that 3 pairs of large cells, and the one pair of the small cells lie opposite each other. Further proximally, a 9th retinula cell is encountered. The fused, centrally located rhabdom is built up by the microvilli of all nine retinula cells. The rhabdom ends at 4 basal pigment cells. In dark adapted ommatidia, a ring of large intracellular vacuoles is to be seen immediately peripherally to the rhabdom. The outer, cytoplasmic zone of the retinula cells contains many pigment granules and mitochondria; multivesicular bodies, onion bodies and Golgi apparatus are of relatively rare occurrence. The functional significance of the ommatidial structure and the arrangement of the cell organelles in the dark adapted condition are discussed.
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  • 72
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    Cell & tissue research 128 (1972), S. 538-554 
    ISSN: 1432-0878
    Keywords: Arteries ; DOCA hypertension ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the unconstricted superficial epigastric and femoral arteries is described in normal rats and in animals with hypertension induced by unilateral nephrectomy, by subcutaneous injections of desoxycorticosterone acetate and drinking of 1% NaCl. The femoral artery showed by far the greater response to the DOCA-saline treatment. In both vessels, the smooth-muscle cells changed from the normal spindle shape to a blunt ended outline with numerous pinocytotic vesicles and prolific collagen production. With long term hypertension, particularly in the femoral artery, the smooth-muscle cell profiles became very irregular. Hypertrophy of the organelles of the smooth-muscle cells was associated with an increase in the intercellular material which gradually changed from a mainly collagenous character to mainly vesicular. Lysosomal activity indicated cell disintegration. White blood cells adhere to the endothelium in hypertensive rats and there was an increase in subendothelial material. The number of intimal smooth-muscle cells increased noticeably in the femoral artery. In both arteries, the adventitial fibroblasts hypertrophied in hypertensive rats. In animals with an elevated blood pressure the morphological response was observed as early as 4 to 7 days after initiation of treatment.
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  • 73
    ISSN: 1432-0878
    Keywords: Muscle tissue ; Pentastomid ; Body wall ; Parasite ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the body wall muscle of the pentastomid Reighardia sternae is described. The muscle fibres are separated from one another and form two layers, circular and longitudinal. They are cross-striated with approximately 11 actin filaments surrounding each myosin filament. The T-system consists of simple in-pushings of the sarcolemma. The SR is also simple and forms both dyadic and triadic contacts with the T-system tubules and dyadic contacts with the sarcolemma. Electron-dense inclusions occur, usually in the vicinity of the Z-lines, and it is suggested that these may be composed of unsaturated lipids.
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  • 74
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    Cell & tissue research 130 (1972), S. 279-301 
    ISSN: 1432-0878
    Keywords: Gonadal development ; Sex determination ; Germ cells ; Mollusca ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A cytological study has been made, at the light- and electron-microscope levels, of gonadal development in Arion circumscriptus. The gonad appears to be ectodermal in origin and is composed of two cell lines—germinal and non-germinal. These two lineages are established in the embryo. The germinal line is first represented by primordial germ cells while the non-germinal line is first represented by auxiliary cells. The primordial germ cells differentiate into spermatogonia and oogonia, the auxiliary cells into Sertoli cells and follicular cells. Spermatogonia and oogonia differentiate about the time of hatching. All subsequent germ cells appear to differentiate from these initial populations of spermatogonia and oogonia. The concept of a germinal epithelium, as a cell layer in which germ cells differentiate from indeterminate germ cells throughout the life cycle, is not supported by this study. A model for sex determination of the germ cells is proposed based on the hypothesis that sexually non-determined primordial germ cells are distributed into two physiologically isolated compartments (a male medullar compartment and a female cortical compartment). The spermatogonia and oogonia then differentiate in two different microenvironments.
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  • 75
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    Cell & tissue research 132 (1972), S. 67-78 
    ISSN: 1432-0878
    Keywords: Salivary glands ; Octopus ; Secretory fibers ; Synapse ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les nerfs sécréteurs pénètrent dans l'épithélium des tubules au niveau du hile de la glande. Leurs subdivisions se disposent entre les cellules épithéliales ou leurs replis, et gardent toujours une situation extracellulaire. Les plus gros faisceaux d'axones sont encore entourés par des cellules satellites qu'on n'arrive plus à discerner autour des faisceaux moins importants ou autour des fibres isolées. Les axones sont alors directement au contact des cellules glandulaires. On a pu trouver des synapses neuro-glandulaires avec des spécialisations membranaires asymétriques comparables à celles décrites dans le système nerveux central des Vertébrés. Les fibres sécrétrices variqueuses contiennent d'autre part des vésicules de types variés, semblables à celles des troncs sécréteurs et moteurs du canal, et à celles des fibres motrices de la glande. La signification de ces vésicules a été discutée en relation avec l'existence possible d'amines biogènes diverses dans les fibres nerveuses.
    Notes: Summary The secretory nerves enter the tubule epithelium at the level of the gland hilus. Their subdivisions being located between the epithelial cells or their infoldings, have always extracellular position. Satellite cells still surround the largest axon bundles, but are no longer discernable round the smaller bundles or isolated axons which are thus in direct apposition with glandular cells. Neuro-glandular synapses, with asymetric membrane specialisations similar to those found in the central nervous system of vertebrates, have been found. The varicose secretory fibers contain various types of vesicles, similar to those found in the secretory or the motor trunks at the duct level, or in the gland motor fibers. The significance of these vesicles is discussed, in reference to the possible existence of various biogenic amines in the nerve fibers.
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  • 76
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    Cell & tissue research 132 (1972), S. 95-106 
    ISSN: 1432-0878
    Keywords: Olfactory sensilla ; Insects ; Necrophorus ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Auf dem Endglied der Antenne von Necrophorus wird eine neue Sensillenform als Sensillum coelosphaericum beschrieben. Anhand von Merkmalen des cuticulären Apparates werden 2 Typen dieses Sensillums unterschieden. 2. Die Wand des cuticulären Apparates ist von einem Porensystem durchbrochen, das als reizleitende Struktur angesehen werden kann. Abweichend vom Porensystem basiconischer Sensillen finden sich bei den Sensilla coelosphaerica statt der Porentubuli sackförmige Bildungen, die aus einem dreidimensionalen Gitterwerk von miteinander vernetzten Filamenten bestehen. Diese Filamentsäcke enden bei Sensillum coelosphaericum Typ I in Einbuchtungen der 3. Hüllzelle, die hier den cuticulären Apparat auskleidet; bei Typ II grenzen sie an den äußeren Liquorraum. 3. Bei beiden Typen der Sensilla coelosphaerica werden die Dendriten auch innerhalb des cuticulären Apparates von einer Scheide umgeben. Das reizleitende System reicht nicht bis in unmittelbare Nähe der Dendriten. Die räumliche Anordnung der Strukturen führt zu der Auffassung, daß Duftmoleküle die Dendritenmembran nicht allein durch Grenzflächen-Diffusion erreichen Können.
    Notes: Summary 1. A new type of olfactory sensilla, named Sensillum coelosphaericum, was found on the distal segment of the antenna of the Carrion beetle Necrophorus. Two types of sensilla are differentiated by characteristics of their cuticular apparatus. 2. The wall of the cuticular apparatus is penetrated by pores which may function in the conduction of stimuli. The sensilla coelosphaerica differ from the basiconic sensilla in that they do not have pore tubules but have sac-like structures consisting of a three-dimensional network of filaments. In sensillum coelosphaericum type I, these sacs end in infoldings of a third enveloping cell which in this type coats the inside of the cuticular apparatus; in type II, on the other hand, the sacs of filaments border the outer liquor space. 3. Within the cuticular apparatus in both types of sensilla coelosphaerica, the dendrites are surrounded by a dendritic sheath. The stimulus-conducting system does not contact the dendrites. The arrangement of these structures implies that odour molecules can also reach the dendrite membrane by other means than surface diffusion.
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    Cell & tissue research 132 (1972), S. 333-364 
    ISSN: 1432-0878
    Keywords: Pituitary gland ; Amphibians ; Corticotrophs ; Ultrastructure ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'identification des cellules responsables de l'élaboration de la corticotropine (ACTH) a été envisagée chezRana esculenta. Les effects causés par l'interrénalectomie au niveau de l'hypophyse ont été étudiés parallèlement par immunofluorescence et au microscope électronique. Au microscope à fluorescence, les cellules détectées chez les animaux témoins avec un antisérum anti-synachten1 bordent en grand nombre les capillaires des zones médiorostrale et ventrale du lobe antérieur. Deux jours après interrénalectomie, le nombre de cellules fluorescentes décroît, douze jours après l'intervention, il ne subsiste pas d'éléments fluorescents dans cette zone. Au microscope électronique, les cellules corticotropes présentent de fines granulations d'environ 200 mμ de diamètre. Après interrénalectomie bilatérale, ces cellules sont fortement stimulées, elles sont sujettes à d'importantes modifications morphologiques; l'aspect morphologique des autres catégories de cellules antéhypophysaires, par contre, n'est pratiquement pas modifié. Douze jours après l'opération, la plupart de ces cellules sont dégranulées, l'ergastoplasme et l'appareil de Golgi sont bien développés. Ces observations suggèrent que les cellules péricapillaires de la moitié rostrale de lapars distalis sécrètent l'hormone corticotrope.
    Notes: Summary Identification of the cell types responsible for the production of adrenocorticotropin (ACTH) was performed inRana esculenta. The effects of interrenalectomy on the pituitary cells were studied as well by immunofluorescence, as by electron microscopy. In control animals, the ACTH cells studied by immunofluorescence are numerous around the blood vessels of the medio-rostral and medio-ventral part of the anterior lobe. Two days after interrenalectomy the number of fluorescent cells decreases. Twelve days after, the operation all the fluorescent cells disappeared. The fine structure of the corticotrophs is characterized by the presence of small secretory granules (200 mμ). After bilateral interrenalectomy this cell type is markedly stimulated; it displays striking morphological changes, while the morphology of the other pituitary cell types is not considerably modified. Twelve days after operation most of these cells are degranulated, the rough endoplasmic reticulum and the Golgi apparatus are well developed. These findings suggest that the pericapillary cells of the rostral half of thepars distalis produce the adrenocorticotrophic hormone.
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  • 78
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    Cell & tissue research 132 (1972), S. 431-450 
    ISSN: 1432-0878
    Keywords: Organ of bellonci (Anaspides tasmaniae) ; Crustacea ; SPX organ ; Receptor ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The organ of Bellonci of Anaspides tasmaniae (Thomson) (Crustacea, Syncarida) is described light and electron microscopically, and a few histochemical tests are reported. Located ventrally in the eyestalk below the medulla interna, the organ is composed of a number of cavities. These are similar in structure in their contents and associated cellular components, which include two types of glia cells delimiting each cavity and the terminal parts of a few dendrites. Each dendrite usually bears two cilia, which project into the cavity where they split up into numerous branches. The organ is supplied by three nerve tracts: two from the medulla terminalis and one from the medulla interna. The sensory pore, which is innervated from the medulla interna, is not closely associated with the organ of Bellonci in Anaspides. No marked secretory activity is detectable by histochemical or ultrastructural observations. It is thought that the organ has a sensory function.
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    Cell & tissue research 133 (1972), S. 289-325 
    ISSN: 1432-0878
    Keywords: Nematosomes ; Neurons ; Substantia nigra ; Rat and Cat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Distinctive cytoplasmic inclusions, termed nematosomes, have been identified in the neurons, but not in the glial cells of the substantia nigra in the rat and the cat. These organelles which lack a limiting membrane consist of an entanglement of more or less tightly packed microfilaments or filamentous strands. According to the tridimensional arrangement of their filamentous components, as well as to their size and boundary, the nematosomes usually display several structural types: (a) round or oval, dense, filamentous bodies; (b) reticular inclusions with or without excavated centers; (c) ill-defined small aggregates of fine filaments. At higher magnification, each microfilament or filamentous strand, whatever the type of nematosome, is itself composed of similar subunits, about 20 Å in diameter. It should be pointed out that the latter subunits may be fine deposits of heavy metal on structural components of nematosomes, which appear to be similar in every structure. The ultrastructural organization of a given nematosome may vary from one portion to another. The functional significance of such structural variations from one nematosome to another, and even within a given nematosome, could not be elucidated by means of our ultrastructural study, although additional cytochemical and radioautographic work may throw light on this problem. These cytoplasmic bodies are present in the perikaryon of most neurons and one or more inclusions are usually observed in the same nerve cell. They are infrequently seen in the dendritic or axonal processes. The nematosomes are closely associated with the other cytoplasmic organelles filling the ground substance of neurons by means of microfilaments projecting from their surface. These cytoplasmic inclusions are, however, most frequently linked to surrounding free ribosomes and rough ER profiles. The association of free ribosomes with excavated nematosomes, which in turn contain neurofilaments in their core, suggests that these structures consist, partly at least, of precursor material which is assembled into the structural proteins of the neurofilaments after being synthesized by the neighbouring ribosomes. No special relationship with the neurotubules has been noticed. Nematosomes have also been found in structural relationship with other organelles, i.e. the smooth tubules and vesicles, the Golgi apparatus, the coated vesicles, the lysosomes and the mitochondria. The nematosome may be also closely associated with the subsynaptic web of axosomatic synapses and these two cytoplasmic components display many structural similarities. In the light of these and previously reported observations, it would appear that nematosomes are not incidental cytoplasmic inclusions, but common organelles of certain types of neurons.
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    Cell & tissue research 133 (1972), S. 463-474 
    ISSN: 1432-0878
    Keywords: Teleost ; Ultrastructure ; Red muscle ; White muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Es wurden die Feinstruktur roter und weißer Muskelfasern des Seewasserteleostiers Seelachs (Gadus virens) untersucht und ultrastrukturelle Messungen und Analysen durchgeführt. Die Sarcomerlängen der roten Fasern liegen zwischen 1,60 und 1,82 μ, die der weißen zwischen 1,70 und 1,85 μ. Hinsichtlich des prozentualen Vorkommens von sarcoplasmatischem Reticulum und T-System bestehen zwischen roten und weißen Fasern keine wesentlichen Unterschiede. Beide Fasertypen zeichnen sich durch regelmäßiges Vorkommen von Triaden am Z-Streifen, deutliche M-Streifen und multiple Innervation aus. Ultrastrukturell unterscheiden sich die beiden Fasertypen dadurch, daß die roten Fasern dickere Z-Streifen und mehr Mitochondrien, die weißen peripher bandförmige Myofibrillen besitzen. Die Struktur der Fasern dieser beiden Muskeltypen wird im Hinblick auf deren mögliche Rolle beim Schwimmen diskutiert.
    Notes: Summary The fine structure of the red and white myotomal muscles of a marine teleost, the coalfish Gadus virens, has been examined and ultrastructural measurements and analyses carried out. The sarcomere lengths of the red and white fibres were found to be 1.60 μ minimum, 1.82 μ maximum and 1.70 μ minimum, 1.85 μ maximum, respectively. No significant difference was found between the red and white fibres in their percentage of sarcoplasmic reticulum and T system. Both were found to have regularly occurring triads at the Z disk level, to have distinctive M lines and to be multiply innervated. Ultrastructurally the two fibres can be distinguished by the thicker Z line and more abundant mitochondria of the red fibre, and by the ribbon-shaped peripheral myofibrils of the white fibres. The structure of the fibres in these two types of muscle is discussed in relation to their possible role in swimming.
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    Cell & tissue research 133 (1972), S. 529-537 
    ISSN: 1432-0878
    Keywords: Statocyst ; Pomacea paludosa ; Ultrastructure ; Cell types ; Ciliary orientation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural observations on the statocysts of the prosobranch gastropod Pomacea paludosa are reported in this paper. 1. The static nerve consists of a great number of naked axons with a diameter of 0.2–0.5 μm. Several axons are joined together to bundles by glia cells (Fig. 1). 2. The epithelium of the statocyst contains 2500–3000 hair (= sense) cells, each with an area of at most 75 μm2 (Fig. 2). This great number of hair cells is compared with the number of receptor cells in other gastropod statocysts. 3. The hair cells are surrounded by smaller supporting cells. The significance of the interlacing of hair and supporting cells and of the possible contact between hair cells is discussed. 4. Supporting cells possess microvilli and sometimes one modified cilium (Fig. 5). The hair cells bear microvilli and 30–40 cilia. These cilia have the typical 9+2 arrangement of the filaments, striated roots to one side of the basal body and a basal foot to the other (Fig. 3). 5. For each sense cell and even for larger areas of the statocyst wall the basal feet point nearly in the same direction (Fig. 4). Hence it is suggested (a) a directional sensitivity for each hair cell and (b) a correlation between the areas of same polarisation and the “groups” of nerve fibers. 6. Different types of vesicles in the nerve layer of the cyst wall (Fig. 6) and stimulation experiments give some evidence for an efferent innervation of the statocysts.
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  • 82
    ISSN: 1432-0878
    Keywords: Lymphocytes ; Plasma cells ; Ductus thoracicus (Rat) ; Osmium-Zinc-Jodide impregnation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Lymphozyten des Ductus thoracicus von unbehandelten weißen Ratten und von Ratten nach Sensibilisierung mit Meerrettichperoxydase wurden nach einer zweistündigen Vorfixierung in 2,5% Glutaraldehyd in dem Osmium-Zink-Jodid-Gemisch nach Maillet (1959) inkubiert und elektronemikroskopisch untersucht. Es zeigte sich, daß bei den unbehandelten Tieren nur wenige Lymphozyten keine Reaktion im Kernspalt aufwiesen — ER und Golgi waren nicht ausgebildet —, während die Mehrzahl der Zellen eine starke OZI-Imprägnation des Kernspalts, des ER, des Golgifeldes und der Mitochondrienmatrix zeigte. Die Membransysteme und Mitochondrien der Plasmazellen, die in der Ductuslymphe nach Sensibilisierung auftraten, waren ebenfalls stark OZI-positiv. Auf Grund dieser Befunde halten wires für sehr wahrscheinlich, daß das OZI-Gemisch mit bestimmten Proteinen reagiert, auch mit Antikörpern. Bei einer Erhöhung des pH-Werte auf 6,5 findet in den genannten Systemen keine Reaktion mehr statt.
    Notes: Summary Ductus thoracicus lymphocytes from untreated white rats and from rats after sensibilisation with horseradish peroxydase were incubated in Maillet's (1959) osmiumzinc-jodide mixture after prefixation in 2.5% glutaraldehyd, and examined electron microscopically. It is demonstrated that among the untreated lymphocytes only few cells show no reaction product in the perinuclear space—ER and Golgi A. are not to be observed—while the majority exhibits strong reaction in the nuclear envelope, the ER, the Golgi field and the matrix of the mitochondria. All plasma cells, present in the thoracic duct lymph after sensibilisation with horseradish peroxidase show also a strong OZI-reaction in their cisternal elements and in the mitochondria. According to these findings there is strong evidence that the OZI-solution reacts with certain proteins also with antibodies. Setting the pH of the OZI-solution to 6.5 no more reaction is found in the formentioned systems.
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  • 83
    ISSN: 1432-0878
    Keywords: Ultimobranchial glands ; Urodeles ; Cell types ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the ultimobranchial (UB) glands of two common laboratory urodeles, viz., larval axolotls, Ambystoma mexicanum Shaw and adult Pleurodeles waltlii Micahelles, is described and compared in what is believed to be the first ultrastructural report on urodele UB glands. The axolotl UB gland shows a wide variety of form, being represented by an elongated diffuse series of follicles and sometimes by one or two large discrete terminal follicular bodies. In these axolotl UB glands up to four cell categories are distinguishable including a tonofilamentous cell and a secretory cell that is possibly homologous with calcitonin-producing C cells of anurans or other vertebrates. These two cell categories are also found in the Pleurodeles gland. The possible significance of the various cells is considered.
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    Cell & tissue research 134 (1972), S. 273-282 
    ISSN: 1432-0878
    Keywords: Swim Bladder ; Gas gland cells ; Misgurnus fossilis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the wall of the rudimentary rear chamber in the swimbladder of the pond-loach was studied. The morphological features of a majority of the cells, as well as the presence of micro-rete mirabile, suggest that epithelial components in the wall of this organ represent a structural and functional equivalent of the gas gland.
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  • 85
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    Cell & tissue research 123 (1972), S. 486-495 
    ISSN: 1432-0878
    Keywords: Pomatoceros triqueter ; Cytokinesis ; Surface folding ; New surface membrane ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The first cleavage division of Pomatoceros triqueter eggs is described. Time-lapse microcinematographic and electron microscopic studies revealed that, prior to division, the plasma membrane was folded into pleats. These were not present after division. This fact pointed to an unfolding of the plasma membrane which enabled it to cover the increased surface area resulting from cleavage. It is suggested that the pre-cleavage folds are derived from the membranes of the cortical granules, which continue releasing their contents into the perivitelline region following fertilization and first division. Filamentous material in the form of a band was present subjacent to the plasma membrane in the region of the furrow. The individual filaments of this band measure 5 to 7 nm in cross section, the dimensions being similar to those described for other kinds of dividing cells.
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  • 86
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    Cell & tissue research 127 (1972), S. 287-305 
    ISSN: 1432-0878
    Keywords: Sensilla ; Insecta ; Diptera ; Musca domestica ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The terminal organs of the cephalic lobes of the house fly larva, Musca domestica L., were studied by scanning and transmission electron microscopy. Six different types of sensilla were found: (1) papilla sensillum, (2) pit sensillum, (3) spot sensillum, (4) modified papilla sensillum, (5) knob sensillum, and (6) scolopidium. The papilla, pit, spot, and modified papilla sensilla have the essential structure of contact chemoreceptors, i.e., the unbranched dendritic tips are exposed externally through a single opening. However, a tubular body, which is a characteristic structure of tactile setae, is also present in some of the dendritic tips. We assume these sensilla serve a dual function—contact chemo- and mechanoreception. The role of the knob sensilla is obscure. The scolopidia present in the dorsal and the terminal organ are probably stress detectors. Two basal bodies occur in the dendritic ciliary region of all sensilla. Both of the basal bodies (except in the scolopidia) give rise to the distal ciliary microtubules as well as the proximal rootlets.
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  • 87
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    Cell & tissue research 127 (1972), S. 323-346 
    ISSN: 1432-0878
    Keywords: Thymus ; Frog ; Development ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A study of the ultrastructure of the developing thymus of the leopard frog (Rana pipiens) revealed that the thymus had undergone all of the major changes which would persist through larval life and metamorphosis by the time that the animals had reached larval stage IV of Taylor and Kollros (1946). These changes included development of an outer, lymphoid cortical region and an inner, essentially nonlymphoid medulla; mitotic activity among lymphoid cell precursors and the formation of the first small lymphocytes; development of complex cysts containing PAS-positive material and the appearance of other signs of secretory activity among epithelial cells of the medulla; and differentiation of large myoid cells containing bundles of striated muscle fibrils. The changes are particularly noteworthy because they first appear during a period in which the animals are known to be developing the capacity to respond immunologically to allografts.
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  • 88
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    Cell & tissue research 127 (1972), S. 439-461 
    ISSN: 1432-0878
    Keywords: Prechiasmatic gland (Organon vasculosum laminae terminalis) ; Rat ; Nerve endings ; Dense-cored vesicles ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary On the basis of the present electron microscopic study of the rat median vascular prechiasmatic gland, the unmyelinated nerve fibers containing dense-cored vesicles may be classified in three categories. (1) Nerve endings containing isomorphic rounded dense-cored vesicles, 800–1600 Å in diameter with a predominance of vesicles between 1100 and 1300 Å. These vesicles are synthesized in the nerve cell perikarya which are localized principally in the lamina profunda of the outer subpial layer and also in the neuropil of the inner glial covering layer. One or more “cholinergic” axon terminals are in contact with the surface of these nerve cell perikarya. The dense-cored vesicles travel in the axonal process which branches into an extensive terminal network characterized by the presence of small varicosities. They abut on the pericapillary spaces but never against another neuron or effector cell. A few nerve processes course between the ependymal cells and terminate in the preoptic recess of the third ventricle. The dense-cored vesicles may contain one of the primary monoamines. (2) Nerve endings containing pleomorphic dense-cored vesicles, 500–1600 Å in diameter with a predominance of vesicles between 800 and 1100 Å. The latter granular vesicles are associated with small, clear-centered vesicles, 260–550 Å in diameter, which are often aggregated in the vicinity of thickenings of the plasma membrane and of cytoplasmic dense projections. The intercellular space and the cell plasma membrane, however, do not display any modification facing these structures. Synapse-like contacts are observed between these nerve endings and cells containing a great amount of microfilaments and glycogen particles in their cytoplasm. The latter cells possibly represent processes of ependymal cells. (3) Nerve endings containing a few large dense-cored vesicles in addition to a majority of synaptic vesicles.
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  • 89
    ISSN: 1432-0878
    Keywords: Hypophyse ; Quail ; Thyroidectomy ; Castration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé On compare l'ultrastructure et la localisation des phosphatases acides au niveau des cellules hypophysaires delta et beta, chez des Cailles mâles thyroïdectomisées et maintenues en photopériode courte ou bien castrées, puis placées en photopériode longue. On étudie en outre, dans ces deux cas, les effets d'injections de doses croissantes de thyroxine. La thyroïdectomie provoque la transformation des cellules delta en cellules de thyroïdectomie groupées en îlots à la périphérie du lobe céphalique. Ces cellules sont pauvres en phosphatases acides. La thyroxine (10 μg/j pendant 2 jours) provoque la régression de ces cellules et l'apparition de lysosomes. Les cellules beta ne sont pas modifiées par la thyroïdectomie. La castration-photostimulation stimule les cellules beta localisées dans le lobe céphalique. Elle provoque dans les deux lobes de la glande l'hypertrophie et la vacuolisation des cellules delta qui se distinguent des cellules de thyroïdectomie par la présence de nombreux lysosomes. La thyroxine freine simultanément l'activation des cellules delta et des cellules beta, en provoquant la formation de lysosomes, mais la dose efficace chez le mâle photostimulé (20 μg et 60 μg/j pendant 5 jours) est sans effet chez le castrat photostimulé (dose efficace 180 μg/j). Pour interpréter ces faits, on admet que les cellules delta, thyréotropes et les cellules beta, gonadotropes, seraient simultanément soumises à un contrôle freinateur des hormones thyroïdiennes et des stéroïdes mâles.
    Notes: Summary The ultrastructure and the localization of acid-phosphatase activity are compared in beta and delta pituitary cells of male Japanese quail, either thyroidectomized and maintained in short days, or castrated then put in long days. Moreover, in these two cases, the effects of brief treatments with increasing doses of thyroxine are studied. Thyroidectomy induces transformation of delta cells into “thyroidectomy cells” arranged in clumps at the periphery of the cephalic lobe. The acid-phosphatase activity of such cells is low. Thyroxine (10 μg per day for two days) causes regression of these cells and the appearance of numerous lysosomes. Beta cells are not modified by thyroidectomy. Castration and exposure to long days stimulate beta cells, localized in the cephalic lobe. It induces, also, in both pituitary lobes, hypertrophy and vacuolization of delta cells which differ from thyroidectomy cells by the presence of numerous lysosomes. Thyroxine in photostimulated quail inhibits both delta- and beta-cell stimulation and increases the frequency of lysosomes but the effective doses on males (20 μg or 60 μg per day for five days) are inactive on castrates, the response of which is obtained with 180 μg per day. In order to explain these data, a hypothesis is suggested: Thyrotropic delta cells and gonadotropic beta cells are both subject to a double inhibiting control by thyroid hormones and male steroids.
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  • 90
    ISSN: 1432-0878
    Keywords: Ultimobranchial glands ; Anurans ; Second cell type ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The comparative fine structure of ultimobranchial (UB) glands of adult Israeli anurans (Bufo viridis, Rana ridibunda, Hyla arborea) taken in the wild during the breeding season is presented. Common aspects of the UB secretory cells are considered with especial reference to secretory granules, lipid droplets and tonofilaments. In B. viridis a second cell type with large electron-dense cytoplasmic granules is found in UB follicles. R. ridibunda and H. arborea UB follicles have a second cell type similar to goblet cells in appearance and these appear to be discharging their mucoid contents into the lumina of the follicles. The possible significance of these various cell types is considered.
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  • 91
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    Cell & tissue research 129 (1972), S. 386-394 
    ISSN: 1432-0878
    Keywords: Acrorrhagi ; Actinia equina ; separation of the ectoderm ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'analyse ultra-structurale de l'acrorrhage d'Actinia equina L. a permis de montrer une adaptation histologique au décollement de l'ectoderme lors de la réponse de l'actinie à une agression. La zone basale et digitée des cellules ectodermiques est très vacuolisée. La turgescence de l'acrorrhage provoque une extension de la mésoglée; on observe un écartement des bases cellulaires et la rupture des vésicules facilite la séparation de l'ectoderme et de la mésoglée. Celle-ci a lieu après ancrage des nématocystes atriches dans les tissus de l'agresseur, et retrait de l'Actinie.
    Notes: Summary The ultrastructural analysis of the acrorhagi of Actinia equina reveals histological adaptations to the specific detachment of this brightly colored strip of ectoderm in case of being attached. The basal zone of the ectoderm cells is highly vacuolated. The turgidity of the acrorhagous provokes an extension of the mesoglea. The separation of the ectoderm is facilitated by rupture of the vacuoles and the specific arrangement of the filament containing branched bases of the cells. When the ectoderm, which contains numerous nematocysts, is fixed in the tissue of a agressor, this one detaches.
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  • 92
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    Cell & tissue research 129 (1972), S. 370-385 
    ISSN: 1432-0878
    Keywords: Androgenic gland ; Crab ; Ocypode quadrata ; Cellular degeneration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'étude ultrastructurale des glandes androgènes du Crabe Ocypode quadrata (Fabr.) révèle l'existence de processus involutifs entraînant une autodestruction cellulaire totale. Cette lyse se produit en des zones non localisées des glandes et n'affecte pas l'activité spermatogénétique du Crabe considéré de plus, la coexistence de cellules en dégénérescence avec des cellules normales traduit un asynchronisme cellulaire. Les différentes modifications conduisant à la dégénérescence ont été décrites: dégranulation de l'ergastoplasme, développement important du réticulum endoplasmique, vacuolisation des mitochondries, différenciation de jonctions cellulaires d'un type particulier, formations de «corps vacuolaires» et de vacuoles autolytiques puis de corps résiduels précédant les processus de fragmentation cellulaire et de pycnose nucléaire. Bien qu'il n'y ait jamais une régression totale des glandes androgènes, ces modifications rappellent celles qui surviennent après la métamorphose dans les glandes de mue des Insectes. La signification physiologique de la dégénérescence cellulaire est discutée.
    Notes: Summary Electron microscopic examination of the androgenic glands of the ghost crab Ocypode quadrata (Fabr.) reveals the existence of involutive processes leading to complete cellular breakdown. This autolysis occurs in non-localized areas of the glands and does not affect the spermatogenetic activity of the crab studied; further, the coexistence of degenerative cells with normal cells shows a cellular asynchronism. The different modifications leading to degeneration have been described: substitution of rough-surfaced endoplasmic reticulum by an important development of smooth reticulum, vaculolization of mitochondria, differentiation of a particular type of cellular junctions, elaboration of “vacuolar bodies” and autolytic vacuoles and then of residual bodies preceding processes of cellular fragmentation and nuclear pyknosis. Although there is never a complete regression of the androgenic glands, these modifications resemble those which take place in the prothoracic glands of insects after metamorphosis. The physiological significance of the cellular degeneration is discussed.
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  • 93
    ISSN: 1432-0878
    Keywords: Saccus vasculosus ; Cerebrospinal fluid contacting neurons ; AChE-positive fibre connections ; Synapses on coronet cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Der Saccus vasculosus von Anguilla anguilla, Cyprinus carpio und Amiurus nebulosus wurde lichtmikroskopisch mit der AChE-Reaktion und dem fluoreszenzhistochemischen Monoaminnachweis, sowie elektronenmikroskopisch untersucht. Lichtmikroskopisch weisen die Liquorkontaktneurone und ihre Fortsätze eine starke AChE-Aktivität auf, während die Krönchenzellen inaktiv sind. Die AChE-positiven Fortsätze der Nervenzellen bilden Bündel, die in den Nervus sacci vasculosi eintreten und im Tractus sacci vasculosi weiterziehen. Diese AChE-positive Bahn kann nach Kreuzung zur Gegenseite bis in das Neuropil des Thalamus ventralis verfolgt werden. Die Liquorkontaktneurone des Saccus vasculosus, der Nervus und Tractus sacci vasculosi, sowie der Nucleus sacci vasculosi weisen keine Monoaminfluoreszenz auf. Auf den Perikaryen der Krönchenzellen kommen Synapsen vor, deren praesynaptisches Cytoplasma außer synaptischen Bläschen und Mitochondrien 800–1000 Å große granulierte Vesikel aufweist. Die Perikaryen der Liquorkontaktneurone enthalten neben den üblichen Cytoplasmabestandteilen dense core Vesikel, deren Durchmesser 700–900 Å beträgt. Axone, in denen granulierte Vesikel (Durchmesser 800 oder 1300 Å) vorkommen, bilden mit diesen Perikaryen Synapsen. Im basalen Teil des Saccusepithels findet man granulierte Bläschen (Durchmesser 800 oder 1400 Å) enthaltende Nervenfasern unterschiedlichen Durchmessers, ferner Synapsen. Der Nervus sacci vasculosi enthält klein- und großkalibrige, marklose Nervenfasern und vereinzelte Synapsen, während der Tractus sacci vasculosi aus vorwiegend kleinkalibrigen, marklosen Fasern besteht.
    Notes: Summary The vascular sac of Anguilla anguilla, Cyprinus carpio and Amiurus nebulosus has been studied by light microscopy using AChE reaction and the fluorescence histochemical method for the demonstration of monoamines, and by electron microscopy. As demonstrated light microscopically, the cerebrospinal fluid (CSF) contacting neurons and their processes exert a strong AChE activity, while the coronet cells are inactive. The AChE-positive processes of the neurons form bundles that enter the nervus sacci vasculosi and pass on in the tractus sacci vasculosi. After crossing to the opposite side, this AChE-positive bundle can be traced into the neuropil of the ventral thalamus. Neither the CSF contacting neurons of the vascular sac, nor the nervus, tractus and nucleus sacci vasculosi show any monoamine fluorescence. As demonstrated electron microscopically, there are synapses on the perikarya of the coronet cells, their presynaptic cytoplasm being characterized by mitochondria, synaptic and granulated vesicles (diameter about 800 to 1000 Å). The perikarya of the CSF contacting neurons contain dense-core vesicles (diameter about 700 to 900 Å) besides of the usual cytoplasmic components. Axons displaying granulated vesicles with a diameter of 800 Å or 1300 Å, form synapses on these perikarya. In the basal part of the saccus epithelium, there are nerve fibres of different calibres containing dense-core vesicles (diameter about 800 Å or 1400 Å) and forming synapses. The nervus sacci vasculosi is characterized by thin and thick, unmyelinated nerve fibres, and rare synapses, while the tractus sacci vasculosi is composed of mainly small, unmyelinated fibres.
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  • 94
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    Cell & tissue research 130 (1972), S. 18-27 
    ISSN: 1432-0878
    Keywords: Oocytes ; Chilopoda ; Vitellogenesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Dans l'ovocyte de Lithobius forficatus L., les trois types classiques de réserves vitellines apparaissent successivement: glycogène, globules lipidiques et vitellus protéique. La synthèse du glycogène semble effectuée au contact des membranes ergastoplasmiques. Les globules lipidiques paraissent élaborés à partir d'un matériel qui transite par le reticulum puis l'appareil de Golgi. Le vitellus protéique est d'origine exogène et pénètre dans l'ovocyte par pinocytose. L'ovocyte mûr est très riche en réserves vitellines et ne renferme qu'une mince couche cytoplasmique périphérique, pauvre en organites.
    Notes: Summary In the oocyte of Lithobius forficatus L., the three classical types of vitelline reserves appear successively: glycogen, lipid droplets, and protein yolk. Glycogen synthesis seems to occur in contact with the rough endoplasmic reticulum. Lipid droplets appear to be elaborated from a material which passes through the endoplasmic reticulum and the Golgi apparatus. Protein yolk originates elsewhere and enters the oocyte by pinocytosis. The mature oocyte is almost completely filled with yolk. There remains only a thin outer coat of cytoplasm with very few organelles.
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  • 95
    ISSN: 1432-0878
    Keywords: Epidermis ; Snails (Lymnaea stagnalis, Biomphalaria pfeifferi) ; Histochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The epidermis and the associated subepidermal gland cells of the freshwater snails Lymnaea stagnalis and Biomphalaria pfeifferi were studied by means of histochemical and electron microscope techniques. The single cell layered epidermis is composed of general epidermal cells, cilia cells and a few scattered goblet cells. The foot sole and the epidermal regions of the pneumostome and the ventral surface of the lips near the mouth consist nearly entirely of cilia cells; elsewhere the cilia cells are found scattered among the general epidermal cells. The apical layer of the general epidermal cells bear microvilli. Numerous mitochondria, vesicles and lysosomes are located in the apical region of the cells. Several Golgi bodies and a poorly developed granular endoplasmic reticulum occur in the supranuclear region; the nucleus lies in the basal part of the cell. The general epidermal cells in the mouth region contain numerous microfilaments compared to the general epidermal cells in the rest of the epidermis. The cilia of the cilia cells in the densely ciliated regions possess well developed roots and basal bodies interconnected by means of the basal feet. With regard to the other cell organelles, cilia cells are quite similar to the general epidermal cells. For comparison a brief study of the ultrastructure of the epidermis of the terrestrial snail Helix aspersa was carried out. The skin of the snail is covered by a mucous layer produced by various gland cells. In L. stagnalis, in addition to the epidermal goblet cells, thirteen subepidermal gland cell types could be distinguished. The histochemistry of the gland cell types is reflected in the ultrastructure. Three of the gland cell types have an ubiquitous distribution, four types are peculiar to the foot, two types to the lips and five types to the mantle. In B. pfeifferi one epidermal gland cell type and only seven subepidermal gland cell types could be distinguished. Most of these gland cells are limited in their distribution to the foot, lips and mantle edge. The observations may provide a basis for further study in the functions of the snail epidermis.
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  • 96
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    Cell & tissue research 130 (1972), S. 489-495 
    ISSN: 1432-0878
    Keywords: Sensilla ; Insecta ; Diptera ; Musca domestica L. ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ventral organs of the cephalic lobes of the house fly larvae, Musca domestica L., were studied by scanning and transmission electron microscopy. Four sensilla were found. Three of them are each innervated by a single dendrite whose ending possesses a tubular body and communicates to the exterior through an opening. These sensilla are assumed to be mechanoreceptors. The 4th sensillum is supplied by 2 bipolar neurons with the unbranched dendritic tips (without tubular bodies) exposed to the exterior through a single opening and is probably a contact chemoreceptor.
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  • 97
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    Cell & tissue research 130 (1972), S. 527-544 
    ISSN: 1432-0878
    Keywords: Ciliated cell rosettes ; Gastrovascular system ; Ctenophores ; Function ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'excrétion et la régulation hydrostatique des Cténaires reposent sur un ensemble qui implique un dispositif unique en son genre: les rosettes ciliées du système gastrovasculaire endodermique. L'originalité de ces rosettes réside dans l'existence d'un puits central mettant en communication directe la mésoglée avec le contenu intravasculaire. Entre ces deux compartiments s'établissement des courants liquides rapides sans sélectivité ionique dont le sens est déterminé par le battement de la seule touffe de flagelles issus de la couronne cellulaire supérieure de la rosette. Lorsqu'une Beroe est placée en milieu marin dilué, on observe au niveau des rosettes un passage de liquide en direction de la mésoglée, alors qu'en eau de mer concentrée, un courant liquide s'établit de la mésoglée vers la lumière des canaux. L'existence d'un diaphragme contractile susceptible d'obturer complètement le puits central de chaque rosette doit permettre éventuellement d'arrêter complètement ces échanges. Cette activité des rosettes conduit à un ajustement de la densité globale du corps de l'animal par rapport à la densité du milieu dans lequel il se trouve.
    Notes: Summary Excretion and hydrostatic regulation of the Ctenophores depend on a particular set of special structures: the ciliated cell rosettes of the endodermal gastrovascular system. The peculiarity of these cell rosettes lies in a free communication between the mesoglea and the lumen of gastrovascular canals. Rapid liquid currents, without ionic discernment, are carried through this hole. The direction of these currents is determined by the beating of the only flagellar tuft borne by the upper cellular crown of rosettes: an aqueous flow may be seen streaming across rosettes towards mesoglea when a Beroe is put in diluted sea water, whereas in concentrated sea water, the flow is streaming from mesoglea to gastrovascular cavity. A contractile diaphragm allows complete closing of the central communication of each rosette and can stop any mesogleal-gastrovascular exchange. This activity of cell rosettes leads to an adjustment of the whole density of animal to that of external sea water.
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  • 98
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    Cell & tissue research 131 (1972), S. 31-45 
    ISSN: 1432-0878
    Keywords: Synapse ; Ultrastructure ; Giant fibre ; Crayfish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of synapses between the cord giant fibres (lateral and medial) and the motor giant fibres in crayfish, Astacus pallipes, third abdominal ganglia have been examined. These electrotonic synapses are asymmetrical, they have synaptic vesicles only in the presynaptic fibre, and they have synaptic cleft widths normally of about 100 Å but narrowed to about 50 Å in restricted areas. Localized increases in density of the synaptic cleft and adjacent membranes also occur within a synapse, and synaptic vesicles are most tightly grouped at the membrane in such areas. Tight or gap junctions with 30 Å or narrower widths have not been found, but the junctions probably function in a similar way to gap junctions. Three small nerves are closely associated with the synapses between the giant fibres. One of these small nerves has round synaptic vesicles and is thought to be excitatory on morphological grounds; one has flattened vesicles and is thought to be inhibitory; and one is postsynaptic to the lateral giant and the two small presynaptic nerves. It is proposed that these small nerves modulate activity in the much larger giant fibre synapse.
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  • 99
    ISSN: 1432-0878
    Keywords: Diplopoda ; Collar gland ; Ultrastructure ; Molting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Die unpaare Glandula perioesophagealis von Polyxenus lagurus ist eine endokrine Drüse. Sie liegt zwischen Pharynxdach und Gehirn. Im Bereich des Hinterkopfs umgibt sie den Vorderdarm manschettenförmig. 2. Die Drüse ist am Nervus glandulae perioesophagealis, der sich in ihr aufzweigt, befestigt. Viele Axone dieses Nervs führen Neurosekret. 3. Die Drüsenzellen sind typische Podocyten. Zwischen ihren Pedicellen erstrecken sich viele weitlumige Interzellularräume. In den Pedicellen findet man zahlreiche Vesikulationen. Benachbarte Pedicellen sind durch Diaphragmata verbunden. DarÜber hinaus sind die Drüsenzellen durch viele „Lysosomen“ und unregelmäßig gewundene, elektronendichte tubuläre Strukturen gekennzeichnet. Das endoplasmatische Retikulum ist spärlich entwickelt. 4. Tiere, bei denen experimentell die Häutung ausgelöst wurde, zeichnen sich durch aktivierte Drüsenzellen aus. Die Anzahl der Mitochondrien, Golgi-Komplexe, „Lysosomen“ und freien Ribosomen steigt jetzt an. Das endoplasmatische Retikulum tritt stark in Erscheinung. Es ist tubulär, häufig angeschwollen und mit flockigem Material gefüllt. Seine Membranen sind überwiegend mit Ribosomen besetzt, stellenweise aber auch agranulär. Jetzt treten auch zusammengesetzte Körper auf.
    Notes: Summary 1. The unpaired glandula perioesophagealis of Polyxenus lagurus is an endocrine gland. It is located in the head between the roof of the pharynx and the brain. In the region of the back of the head it surrounds the foregut like a cuff. 2. The gland is attached to an unpaired “nervus glandulae perioesophagealis” which branches in it. Many axons of this nerve contain neurosecretory granules. 3. The gland cells are typical podocytes. Between their pedicles there are many wide intercellular spaces. A large number of cytoplasmic vesicles are found in the pedicles. Neighbouring pedicles are connected by diaphragmata. Moreover, the cells are characterized by many lysosome-like structures and tubular irregularly-bent electron-dense structures. The endoplasmic reticulum is sparsely developed. 4. In animals in experimentally-induced molting, the gland cells are activated: the numbers of mitochondria, Golgi complexes, lysosome-like structures and free ribosomes are increased. The endoplasmic reticulum is conspicuous; it is tubular, often swollen, and filled with floccular material. It is predominantly granular but smooth in places. Complex cytoplasmic bodies are detectable.
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  • 100
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    Cell & tissue research 132 (1972), S. 147-166 
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Eudendrium ; Hydroidea ; Coelenterata ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Spermatozoa of the colonial marine hydroid, Eudendrium were examined with the electron microscope. The spermatozoa of this species were found to differ greatly in structure from previously described spermatozoa in the phylum. The mature sperm are acrosomeless and retain a considerable amount of perinuclear cytoplasm following their maturation. The perinuclear cytoplasm contains numerous organelles: Golgi apparatus, endoplasmic reticulum, multivesicular bodies, ribosomes and membranous vesicles. The nucleus is elongate and cylindrical, rather than conical, in shape. The four wedge-shaped mitochondria which lie posterior to the nucleus form a fossa which contains proximal and distal centrioles. Centriolar satellites are associated with the distal centriole. The relatively short (15 μ) flagellum consists of two distinct segments: a proximal thick portion and a distal thin portion. The thick segment contains the typical 9+2 arrangement of tubules plus a variable number of peripheral, supernumerary tubules. The thin segment contains from one to eleven tubules. The morphological differences between the spermatozoa of Eudendrium and those of closely related species are discussed with particular reference to sexual life history.
    Type of Medium: Electronic Resource
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