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  • 101
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 13 (1973), S. 83-92 
    ISSN: 1432-0827
    Keywords: Proteoglycan ; Collagen ; Cartilage ; Electron Microscopy ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'élimination de protéoglycans solubles de coupes de cartilage costal de boeuf, par extraction dans une solution de 4M d'hydrochlorure de guanidinium, permet de mettre en évidence des quantités abondantes de collagène dispersé et désagrégé dans la matrice. Les protéoglycanes, résistants à l'extraction, sont visibles sous forme de granules concentrés dans les régions périlacunaires. Les granulations plus importants des protéoglycanes semblent venir du chondrocyte. Dans la matrice, éloignée des chondrocytes, ces granules deviennent plus étroites. Un composant non granulaire “amorphe” masque les fibres de collagène, de telle sorte qu'elles sont difficilement visibles dans le cartilage intact.
    Abstract: Zusammenfassung Die löslichen Proteoglycane wurden mittels Extraktion in 4 M Guanidinhydrochlorid aus Rippenknorpelschnitten des Rindes entfernt. Dies erlaubte die Sichtbarmachung von großen Mengen von verstreuten und auseinandergerissenen Collagen in der Matrix. Die Protoglycane, welche sich nicht extrahieren lassen, erscheinen als kleine, in den perilacunären Regionen konzentrierte Körnchen. Die großen Proteoglycan-Körner scheinen in den Chondrocyten zu entstehen. Sobald sie sich in die Matrix, außerhalb der Chondrocyten, verlagern, werden die Körner kleiner. Ein nicht-granulärer, „amorpher” Bestandteil verhüllt die Collagenfasern, so daß diese im intakten Knorpel nicht deutlich gesehen werden können.
    Notes: Abstract Removal of the soluble proteoglycans from slices of bovine costal cartilage by extraction in 4 M guanidinium hydrochloride permitted the visualization of abundant amounts of dispersed and disaggregated collagen in the matrix. Proteoglycans which are resistant to extraction are seen as small granules which are concentrated in the perilacunar regions. Large proteoglycan granules appear to originate in the chondrocyte. As they come to occupy positions in the matrix distant from the chondrocyte, the granules become smaller. A non-granular, “amorphous” component masks the collagen fibers so that they cannot be readily seen in the intact cartilage.
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  • 102
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 136 (1973), S. 111-120 
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Granular vesicles ; Ultrastructure ; Quantitative evaluation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In order to characterize different sub-zones in the palisade zone of the rat median eminence, quantitative ultrastructural parameters were applied to brains fixed in aldehyde-osmium tetroxide. The palisade zone has been subdivided in 4 successive sub-zones. Increasing numbers of granular vesicles (GV), especially those smaller than 110 nm, are observed from dorsal to ventral sub-zones. There also are more GV per unit area of nervous tissue in the perivascular than in the more dorsal sub-zones. The individual nerve profiles exhibit a larger size in the perivascular layer than in the more dorsal areas, whereas the number and size of nerve profiles devoid of vesicles diminish from dorsal to ventral. As a consequence more GV occur in the perivascular nerve profiles. In the GV containing nerve profiles the concentration of GV is, however, constant in the different sub-zones. A fluctuating size of the preterminal and terminal parts of the nerve fibres is suggested.
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  • 103
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    Springer
    Cell & tissue research 137 (1973), S. 345-359 
    ISSN: 1432-0878
    Keywords: Accessory sex organs ; Male rat ; Prostate ; Seminal vesicles ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A systematic, comparative study of the accessory sex organs of the adult male rat was carried out after intra-aortic perfusion of the pelvic organs with glutaraldehyde. It has been revealed that although the epithelial cells of the different lobes of the prostate have many features in common, it is also apparent that the cell type of the various lobes have specific ultrastructural characteristics of its own, which morphologically distinguish it from the cell type of the other lobes. I.e.: the different lobes may be identified by their specific ultrastructural feature. It is also striking that the lobes, two-by-two, have so many morphological features in common that they may be divided in 3 subgroups. Based on the appearance of amount and localisation of the different organelles, the cells of the lateral lobe and the seminal vesicle are so alike that they morphologically may be classified as one group. Similarly, the coagulating gland and the dorsal lobe form another group, while the ventral lobe as a single form a third group. The few biochemical data from the different lobes which are accessible, seem suggestive to support this subgrouping. Since the various prostate lobes and the seminal vesicles have their homologies in man, further investigation both morphologically and biochemically should be concentrated upon the different groups instead of the single lobe. The study, which describes the different lobes and cell types in detail also show structures which have not been demonstrated within the prostatic epithelium before.
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  • 104
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    Springer
    Cell & tissue research 140 (1973), S. 77-89 
    ISSN: 1432-0878
    Keywords: Intercellular junctions ; Neonatal liver ; Mouse ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Au cours du passage de la vie foetale à la vie postnatale, on note, dans le foie de souris, l'apparition d'associations jonctions-organites cellulaires. Celles-ci cont de deux types: associations desmosomes-organites et associations nexus-organites. 1.Associations nexus-organites. Le long de la «gap junction» sont étroitement accolés, uni ou bilatéralement, divers organites: mitochondrie(s), subsurface cisterna(e), peroxysome(s) ou lysosome. Ces associations n'apparaissent qu'entre le 21ème jour de la gestation et le ler jour post-natal, période à partir de laquelle ils disparaissent au profit d'associations desmosomes-organites cellulaires. Un nouveau type de structure s'associe dans le foie aux membranes plasmatiques: il s'agit des saccules ergastoplasmatiques ou subsurface cisternae. 2.Associations desmosomes-organites. Dans ces complexes, les tonofilaments desmosomiques entrent étroitement en contact avec la paroi des organites cellulaires associés: mitochondrie ou peroxysome. Déjà présents au 13ème jour de la gestation, ces structures s'observent plus fréquemment à partir du ler jour post-natal. La signification de ces associations reste à déterminer, d'autant plus que leur présence a déjà été signalée dans de trés nombreux tissus. Quelques hypothèses sont présentées.
    Notes: Summary During the transition between the fetal and postnatal periods associations between cell junctions and cell organelles appear in the liver of the mouse. These associations are of two types: desmosome-organelle and nexus-organelle. 1.Nexus-Organelles Association. Unilaterally or bilaterally, various organelles — mitochondria, cysternae, microbodies or lysosomes — adhere tightly along the gap. These associations appear only between the 21st day of gestation and the first postnatal day. Thereafter they gradually disappear and are replaced by desmosome-organelle associations. Another type of structure — ergastoplasmic saccules or cisternae of rough endoplasmic reticulum — become associated with the cell membrane. 2.Desmosome-Organelle Associations. In these complexes the desmosomal microfilaments are in close contact with membranes of the associated organelles — mitochondria or peroxysomes. The associations, which exist as early as the 13th day of gestation increase after the first postnatal day. The significance of these associations remains to be ascertained, especially since they occur in many other tissues. A few hypotheses are presented.
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  • 105
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    Cell & tissue research 141 (1973), S. 145-159 
    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Alewife ; Salinity ; Release of hormones ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the alewife the orohypophyseal duct, a remnant of Rathke's pouch, persists in adults as a tube passing from the rostral pars distalis to the pharyngeal region. Its lumen is not open to the buccal cavity. The prolactin cells are situated around the bifurcations of this duct in the rostral pars distalis. Contents from prolactin cells, such as granules, nuclei, mitochondria and Golgi structures were found in these bifurcations. These contents were indistinguishable from those of intact prolactin cells. Evidence of actual release into the duct was often noted. At the presumptive point of release, the cells lining the lumen separate and the contents, probably of an entire prolactin cell, are extruded. The cilia usually found at the point of extrusion arise from prolactin cells. The prolactin cells of freshwater fish were more heavily granulated than those from a marine environment. Prolactin cells of fish entering freshwater streams were not heavily granulated but showed evidence of increased activity. Granule size was not affected by salinity. The ACTH cells are arranged in bands along branches of the neurohypophysis in the rostral pars distalis. No differences in ACTH cells from fish of different salinities were noted.
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  • 106
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    Springer
    Cell & tissue research 141 (1973), S. 103-122 
    ISSN: 1432-0878
    Keywords: Tubal ova ; Pig ; Mitochondria ; Annulate lamellae ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The unfertilized ova of the pig are characterized by the first polar body situated in the perivitelline space. The metaphase chromosomes of the ova are found free in a cortical area, predominantly inhabited by the spindle fibers. Mitochondria show morphological changes in the form of swelling of their matrices. Frequently, the membranes of the individual cristae mitochondriales meet each other, forming meeting points, at regular intervals. The endoplasmic reticulum increases in quantity when compared with that of the pig follicular oocytes (Norberg, 1972b). The Golgi complexes are sparse and scattered. Occasionally, remnants of the end bulbs of the corona radiata cell processes occur below the surface membrane of the ova. Usually, the sperm-penetrated ova contain the first and the second polar body within the perivitelline space. Intranuclear annulate lamellae are observed within the male and female pronucleoplasm, and of particular interest are extended linear structures in one of the pronuclei. These structures may be considered as precursor stage in the formation of the intranuclear annulate lamellae. The parapronuclear cytoplasm is rich in organelles, especially the cytoplasmic annulate lamellae. In contrast to the scarcity of Golgi complexes in the unfertilized ova, many newly formed Golgi vesicles and lamellae reappear in the pronuclear stage. The zona pellucida displays ultrastructural changes following sperm penetration of the ova.
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  • 107
    ISSN: 1432-0878
    Keywords: Nervous tissue ; Specific structures ; Nematosomes ; Neurofilaments ; Neurotubules ; Three-dimensional filamentous network ; E-PTA Stain ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary After the staining of nervous tissue with phosphotungstic acid in absolute ethanol (E-PTA), a selective opacification occurs at certain specific sites, while other structures, especially the plasma and intra-cellular membranes, remain electron-lucent. Among those selectively stained sites, our studies have been focussed on: (1) The dense synaptic material consisting of several presynaptic clumps, termed projections, an intrasynaptic dense line and a subsynaptic web from which fine fibrillar wisps extend into the surrounding ground substance; (2) Neurofilaments and neurotubules, the surface of which is bristled by numerous side-arms; (3) A microfilamentous network intertwines the neurotubules, the neurofilaments and the mitochondria in the dendrites and axon, and is also connected to the E-PTA dense undercoating delineating the inner aspect of the plasma membrane and to the fine wisps emanating from the subsynaptic web. A three-dimensional microfilamentous latticework is thus formed in the nerve cell processes; (4) Dense cytoplasmic inclusions, termed nematosomes, which are usually located in the ground substance of the perikaryon among or in the vicinity of clusters of ribosomes. Tiny microfilaments emanate from the peripheral strands of these bodies. The presence of basic residues in the chains of structural proteins of which consist the subsynaptic web and the nematosome is plausible, since the specificity of the E-PTA staining procedure for the detection of basic residues has previously been put forth. The occurrence of a three-dimensional microfilamentous network in the nerve cell processes led us to hypothesize that it plays a role in translocation of materials. It may provide the motive force for the axoplasmic transport, for instance, with the neurotubules, as well as, plausibly, with the neurofilaments, serving as attachment sites and guideways.
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  • 108
    ISSN: 1432-0878
    Keywords: Testis interstitial cells ; Boar ; Postnatal development ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die postnatale Ontogenese der Hodenzwischenzellen des Schweins nimmt einen wellenförmigen Verlauf und läßt sich in 4 Phasen unterteilen. In der frühpostnatalen Proliferationsphase wandeln sich spindelförmige Zellen in polygonale Leydigzellen um. Dabei beginnt an einem Zellpol die Ausbildung des glatten endoplasmatischen Retikulums. Dieses Organell nimmt in der weiteren Entwicklung einen großen Teil des Zelleibes ein und bildet unregelmäßige Vesikel und konzentrisch geschichtete Zisternen. Es erfolgt eine Vermehrung der Mitochondrien, in ihnen entwickeln sich Tubuli. In der Phase der präpubertären Hypertrophie erreichen die Leydigzellen ihre größten Durchmesser (ca. 30 μm) und sind möglicherweise zu einer Steroidhormonproduktion befähigt. Da das glatte endoplasmatische Retikulum vornehmlich in der Zellperipherie, die übrigen Organellen bevorzugt im Zentrum liegen, sind die Zwischenzellen deutlich zoniert. Die Phase der präpubertären Regression ist durch ausgeprägte Zelldegeneration und Größenabnahme der überlebenden Zellen gekennzeichnet. In der Phase der pubertären Proliferation nehmen die Zwischenzellen erneut an Größe zu. Parallel hierzu vermehren sich Mitochondrien und glattes endoplasmatisches Retikulum. Beide Proliferationsphasen innerhalb der postnatalen Ontogenese werden durch das Auftreten zahlreicher Cytoplasmafilamente eingeleitet, deren Menge sich danach wieder verringert. Unabhängig von dem wellenförmigen Verlauf der Zwischenzellentwicklung ist die Ausbildung von Lysosomen, Microbodies, Mikrovilli, typischen Zellhaften und in der Zellperipherie gelegenen Polyribosomen. Die Leydigzellen sind von einer basalmembranähnlichen Struktur umgeben. Die Mitochondrien enthalten zu allen Zeiten durch elektronendichtes Material verkittete Tubuli.
    Notes: Summary The postnatal development of porcine testicular interstitial cells proceeds in a wave-like manner and may be divided into four periods. In the period of early postnatal proliferation fusiform intertubular cells change into polygonal Leydig cells. This process starts with formation of smooth endoplasmic reticulum in one of the cell poles. Later the smooth endoplasmic reticulum is abundant and consists of irregular vesicles and concentrically arranged cisterns. Mitochondria increase in number and develop tubular cristae. In the period of prepubertal hypertrophy Leydig cells reach maximal size (approx. 30 μm) and possibly may be capable of androgen biosynthesis. The cells of this period exhibit two different zones, since the smooth endoplasmic reticulum prefers the periphery, the other organelles, however, occupy the central region of the cells. The period of prepubertal regression is characterized by cellular degeneration and diminuation of the surviving interstitial cells. In the period of pubertal proliferation an increase of Leydig cell size is accompanied by multiplication of mitochondria and development of smooth endoplasmic reticulum. Both periods of proliferation are initiated by appearance of numerous cytoplasmic filaments which subsequently decrease in number. Interstitial cells of all periods studied exhibit the following features: They possess lysosomes, microbodies, polyribosomes, microvilli and are surrounded by a kind of basement membrane. Cell connections appear as tight junctions and desmosome-like structures. The mitochondria contain closely packed tubules joined by electron dense material.
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  • 109
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    Cell & tissue research 143 (1973), S. 569-586 
    ISSN: 1432-0878
    Keywords: Fish (Macropodus opercularis) ; Muscle Origin ; Myofilaments ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Am Beispiel der Muskulatur von Macropoden wird gezeigt, wie sich aus undifferenzierten Zellen ein Verband gleichartig differenzierter Zellen aufbaut. Einkernige Praemyoblasten ohne Myofilamente bilden sich zu mehrkernigen Myoblasten um. In diesen erscheinen die ersten Myofilamente in streng geordneter Weise: parallel zur Zellmembran und in deren Nähe entstehen Myofilamente unterschiedlicher Länge, wobei Aktin und Myosin etwa gleichzeitig auftreten. Das Z-Scheiben-Material konnte in sehr frühen Stadien erkannt werden. Polysomen stehen in enger räumlicher Beziehung zu den sich ausbildenden Myofilamenten. Vorwiegend in der Zellperipherie entwickeln sich die Myofibrillen aus sog. „crude sarcomeres“. Sie zeigen noch nicht die charakteristische Einteilung in A-und I-Bänder. Im Verlauf der weiteren Entwicklung richten sich die Z-Scheiben parallel zueinander aus und die A- und I- sowie H- und M-Bänder erscheinen in ihrer definitiven Form. Ein Dickenwachstum des Muskels kann dadurch entstehen, daß noch vorhandene Praemyoblasten sich in charakteristischer Form ausdifferenzieren und den Muskel durch Apposition von Myofibrillen marginal verstärken.
    Notes: Summary During ontogenesis of the fish, Macropodus opercularis, uninucleated praemyoblasts without any myofilaments fuse to form multinucleated myoblasts. Within the myoblasts, parallelly and longitudinally arranged myofilaments of different lengths appear close to the cell membrane and in close relation to polysomes. Actin and myosin are detectable in the filamentous form at approximately the same time. This process of sarcomere differentiation starts from so-called “crude sarcomeres” lacking the characteristic arrangement in A-and I-bands. Subsequently, Z-disks are arranged parallel to each other, and A- and I-bands as well as H- and M-bands appear in their definite forms. There are indications that the muscle fibre grows in thickness by additional fusions with still existing praemyoblasts and marginal apposition of further myofibrils.
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  • 110
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    Cell & tissue research 144 (1973), S. 435-452 
    ISSN: 1432-0878
    Keywords: Muscle spindles ; Intrafusal fibre types ; Development ; Deefferentation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Muscle spindles of limb muscles were deefferented in neonatal rats by sectioning ventral roots or by removal of the lumbosacral spinal cord. Ten to 56 days after the operation, muscle spindles were examined in the medial gastrocnemius, extensor digitorum longus and soleus muscles. The differentiation of muscle spindles was not affected by deefferentation. The number of spindles in the investigated muscles was not reduced. Intrafusal fibres increased in number from two at birth to four per spindle on the average, as in normal muscles. The characteristic ultrastructural distinctions of nuclear bag and nuclear chain fibres developed as under normal conditions. However, intrafusal fibres atrophied slowly after fusimotor denervation, their polar zones becoming reduced in diameter by about 25% in comparison with control fibre diameters. Spindle capsules, on the other hand, increased in size and attained diameters comparable with normal spindles, appearing even somewhat distended. As intrafusal fibres degenerate after complete denervation at birth (Zelená, 1957), but differentiate in the absence of fusimotor innervation, it can be concluded that sensory nerve terminals induce and support their development. It is assumed that the morphogenetic influence of sensory terminals is mediated by release and uptake of a trophic substance at the synaptic junction. The occurrence of light and dense core vesicles in the sensory terminals and of coated invaginations and vesicles at both the axonal and plasma membrane speak in favour of such a possibility.
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  • 111
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    Cell & tissue research 144 (1973), S. 475-487 
    ISSN: 1432-0878
    Keywords: Luteal cells ; Luteinization ; Endoplasmic reticulum ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Hyrax possess luteal cells with many ultrastructural features similar to those described in other mammalian species. The process of luteinization is gradual. Cells with increasing amounts of smooth endoplasmic reticulum become predominant in the developing gland. The luteal cells of Procavia and Heterohyrax show many ultrastructural similarities. In both species the corpus luteum persists throughout pregnancy.
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  • 112
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    Cell & tissue research 146 (1973), S. 501-515 
    ISSN: 1432-0878
    Keywords: Median eminence (Rat) ; Granular vesicles ; Ultrastructure ; Quantitative evaluation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A quantitative evaluation has been made of the sizes of neuronal granular vesicles (GV) in different (sub-)zones of the rat median eminence. On the basis of the frequency distribution of the mean sizes of the GV in the individual nerve profiles, at least 4 tentative categories of nerve profiles may be distinguished. However, available data do not permit characterization of nerve fibre categories in terms of neurohormone and/or neurotransmitter storage. From dorsal to ventral the palisade zone shows a decrease in mean size of GV; furthermore, the relative number of nerve profiles characterized by small GV (mean size smaller than 112 nm) increases. In contrast, the GV in the zona granulosa, that part of the external zone of the median eminence ventral to the palisade zone, are of relatively large size. Qualitative observations indicate that the zona granulosa may be regarded as an area for both storage and release of biologically active substances.
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  • 113
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    Cell & tissue research 138 (1973), S. 239-259 
    ISSN: 1432-0878
    Keywords: Ovary ; Gastropoda ; Oocytes ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Oocyten von Viviparus contectus gehören zu den kleinsten, bei Mollusken bekannten Oocyten und enthalten nur wenig Dotter. Nach licht- und elektronen-mikroskopischen Untersuchungen kann die Oogenese in drei Stadien eingeteilt werden. Oocyten des ersten Stadiums zeichnen sich durch das Vorkommen extrem polymorpher Kerne, durch annulate lamellae und schüsselförmige Mitochondrien aus. Große, konzentrisch geschichtete Systeme des granulären endoplasmatischen Retikulums und ein gut entwickelter Golgi-Apparat sind typisch für Oocyten des zweiten, prävitellogenetischen Stadiums. Oocyten dieses Stadiums enthalten außerdem große Nukleolen und andere Kerneinschlüsse unbekannter Funktion, deren Ultrastruktur beschrieben wird. Diese Einschlüsse werden mit dem sog. Binnenkörper der Insekten verglichen. Oocyten des dritten Stadiums, der Vitellogenese, enthalten zahlreiche paraplasmatische Einschlüsse wie dense bodies, Multivesikulärkörper und polymorphe Cytosomen, Fetttropfen und Glykogen. Dense bodies, Multivesikulärkörper und polymorphe Cytosomen enthalten Massen eines Ferritin-ähnlichen Eisenproteins und saure Phosphatasen. Das endoplasmatische Retikulum und der Golgi-Apparat sind an der Dottersynthese beteiligt. Die extrem geringe Größe der Oocyten und ihr Mangel an Dotter dürfte mit der Viviparie der Tiere in Zusammenhang stehen. Da die Eiweißdrüse und Drüsenzellen des Oviduktes große Mengen sekundären Dotters liefern, ist zu vermuten, daß die Oocyte mit ihrer niedrigen Transkriptionskapazität zusätzlich mit nur wenigen wichtigen Substanzen wie lytische Enzyme für den Beginn der Embryogenese und Eisenprotein ausgestattet wird. Viele Oocyten degenerieren im Ovar. Die mit der Degeneration einhergehenden Veränderungen der Ultrastruktur werden beschrieben.
    Notes: Summary The oocytes of Viviparus contectus belong to the smallest oocytes known in molluscs and contain relatively small amounts of yolk. As shown by light- and electron microscopy, oogenesis can be divided into three stages. Oocytes of the first stage are characterised by the occurrence of extremely polymorphic nuclei, of annulate lamellae and cup-like mitochondria. Large systems of rough endoplasmic reticulum, arranged concentrically and a well developed Golgi apparatus are typical for oocytes of the second, the previtellogenetic stage. Oocytes of this stage also contain large nucleoli and other nuclear inclusions of unknown function, whose ultrastructure is described. These inclusions may be compared with the so called “Binnenkörper” of insects. Oocytes of the third stage, the vitellogenesis, contain a large amount of paraplasmic inclusions such as dense bodies, multivesicular bodies and polymorphic cytosomes, fatty yolk droplets and glycogen. Dense bodies, multivesicular bodies and polymorphic cytosomes contain masses of a ferritin-like iron protein and acid phosphatases. It is supposed that the endoplasmic reticulum and the Golgi apparatus are engaged in yolk production. The extremely small size of the oocytes and their lack in yolk should be seen in connection with the vivipary of the animals. As there are large amounts of secondary yolk provided by the albumen gland and glandular cells of the oviduct, it is supposed that the oocyte having a low transcription capacity needs to be supplied, in addition, with only few essential substances such as lytic enzymes for the early stages of embryogenesis and iron protein. Many oocytes usually degenerate inside the ovary. The changes in ultrastructure during the degeneration are described.
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  • 114
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    Cell & tissue research 140 (1973), S. 445-449 
    ISSN: 1432-0878
    Keywords: Cecum, Colon ; Mouse ; Glycocalyx ; Intestinal microorganisms ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the cecal epithelium of the mouse resembles that of more distal parts of the colon. A brief discussion is presented of the possible significance of apical cytoplasmic granules to the glycocalyx and of the close association of microorganisms with the lining epithelium.
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  • 115
    ISSN: 1432-0878
    Keywords: Sympathetic ganglion ; Granule-containing cells ; Synapses ; Three-dimensional analysis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The surface of 4 granule-containing cells, in a cluster within the rat superior cervical ganglion, was studied by a serial sampling technique for electron microscopy. The result shows that all the 4 cells receive one, or three afferent synaptic boutons from the preganglionic fibers impinging upon their somata, and a somatic efferent synapse exists at two locations on each soma of the 2 of these cells. The postsynaptic element of the efferent synapse is observed to be represented by non-vesiculated and vesiculated segments of dendrites, soma and a possible axon collateral of the adrenergic principal neuron of the ganglion. There is a remarkably constant development of the attachment plaque between the granule-containing cells themselves, representing 1.7–2.3% of surface area for each cell. The surface area exposed to the extracellular space (covered only by a basal lamina) varies from 0.1 to 2.3% of the total perikaryal surface of the 4 cells. A tendency is noted that those cells without efferent synapses possess a more extensive area exposed to extracellular space than those forming somatic efferent synapse to the postganglionic elements.
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  • 116
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    Cell & tissue research 142 (1973), S. 89-102 
    ISSN: 1432-0878
    Keywords: Photoreceptors ; Larva ; Hemichordate ; Ultrastructure ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The eyespots of tornariae of enteropneusts (Ptychodera flava from Hawaiian waters and an unknown species from southern California) were studied by electron microscopy. An ocellus is composed of two types of cells: sensory and supportive. The former is characterized by a bulbous cilium (with 9+2 axoneme) at its distal end, one or sometimes two arrays of microvilli from its sides below the cilium, and a basal axon. The latter features large, clear vesicles which presumably contained the reddish-orange pigment seen in the ocellus of a living larva. Five-day old tornariae of P. flava are positively phototactic. Both cilium and microvilli may function as photoreceptors. The tornarian ocellus studied is compared with eyespots of other invertebrates, and the evolutionary significance of its putative photoreceptors is discussed.
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  • 117
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    Cell & tissue research 142 (1973), S. 525-537 
    ISSN: 1432-0878
    Keywords: Lutein cells ; Guinea pig ; Sexual cycle ; Pregnancy ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Feinstructur der Luteinzellen des Meerschweinchens während Schwangerschaft (15., 35., 45., 50., 55., 63. und 2 Tage nach der Geburt) und Zyklus (9, 14, 16, 20 Tage nach der Ovulation) wurden elektronenmikroskopisch untersucht. In den aktiven Luteinzellen kann man konzentrisch um die Lipoidtropfen angeordnete Strukturen des agranulären endoplasmatischen Retikulum beobachten, die später durch Membranstrukturen des granulären endoplasmatischen Retikulum ersetzt werden. Die Mitochondrien sind rund und enthalten tubuläre Innenstrukturen, die Lipoidtropfen sind elektronenoptisch dicht. Während der Rückbildung des Corpus luteum setzt sich das endoplasmatische Retikulum aus ungeordneten Vesikeln und Tubuli zusammen, die Mitochondrien sind länglich oder verzweigt, die Lipoidtropfen elektronenoptisch hell. Die Bedeutung dieser feinstrukturellen Veränderungen in der Luteinzelle wird diskutiert.
    Notes: Summary The fine structure of the lutein cells in guinea pigs corpora lutea of pregnancy (15th, 35th, 45th, 50th, 55th, 63th day and 2 days after birth) and during oestrous cycle (9, 14, 16, 20 days after ovulation) is described. During the active phase of the corpus luteum the formation of concentric whorls of agranular endoplasmic reticulum around lipid droplets is observed, but later the granular endoplasmic reticulum increases. In this stadium the mitochondria are round with tubulous cristae and the lipid droplets are increased in density. During the involution of the corpus luteum the endoplasmic reticulum does not form concentric whorls, the mitochondria are elongated, polymorphic, the lipid droplets have lower electron density. These ultrastructural changes in the lutein cells are discussed concerning the role of the cell organelles in the steroid synthesis.
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  • 118
    ISSN: 1432-0878
    Keywords: Dense core vesicles ; Ultrastructure ; Mollusc ; Nervous system ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopy of the cerebro-visceral connectives of Anodonta cygnea shows numerous long rows of dense core vesicles within the smaller axons of the connectives. These vesicles are often linked together by bridges of electron-dense material reinforced by one or more “arms”. The use of the tilting stage on the electron microscope, which allows the bridges to be examined from different angles, confirms the presence of these vesicular connections. Sub-cellular fractionation of the cerebro-visceral connectives was carried out to study the nature of these bridged dense core vesicles. In the negatively stained vesicle fraction two or more dense core vesicles are joined in a row by connections similar to the vesicular bridges of the intact connective. In the fixed vesicle fraction, many of the dense core vesicles are connected by bridges but long rows of bridged vesicles are not seen. The functional significance of the vesicular bridges is discussed. Preliminary findings of this work have been reported previously (McLaughlin and Howes, 1973).
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  • 119
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    Cell & tissue research 145 (1973), S. 213-227 
    ISSN: 1432-0878
    Keywords: Sensory pore ; Crustacea ; Natantia ; Chemoreceptor ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'observation ultrastructurale du pore sensoriel de plusieurs espèces de Natantia révèle un complexe double. Un premier organe, le pore sensoriel principal, comprend une assise de cellules de soutien encadrant les parties distales de corps de cellules sensorielles. Ces cellules sensorielles portent des segments externes ciliaires qui se divisent dans une cavité sous-cuticulaire aplatie. En regard, la cuticule est amincie et comporte des micropores en forme de cratère et disposés par paires. A côté du pore sensoriel principal, un deuxième organe, le pore sensoriel latéral, est de taille plus réduite et est plus difficile à observer. Sous une invagination digitée de l'épicuticule, existe une cavité de forme complexe où s'épanouissent les segments externes ciliaires d'un faisceau de cellules sensorielles. Le pore sensoriel principal et le pore sensoriel latéral ont une ultrastructure de chémorécepteur.
    Notes: Summary Ultrastructural observation of the sensory pore of several species of Natantia reveals a twofold organ. A main sensory pore (M.S.P.) comprises a layer of supporting cells which encapsulate the terminal region of sensory cell bodies. These sensory cells include two ciliary processes dividing into a flat sub-cuticular cavity. The cuticle opposite is thin and perforated with crater-like paired micropores. Next to the main sensory pore, a second organ, the lateral sensory pore (L.S.P.), is smaller and more difficult to observe. A complex-shaped cavity underlies a contorted epicuticular invagination. Ciliary outer segments, belonging to a bundle of sensory cells, branch out in this cavity. M.S.P. and L.S.P. appear to be chemoreceptors.
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  • 120
    ISSN: 1432-0878
    Keywords: Muscle ; Fish ; Starvation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effect of 16 weeks total starvation on the ultrastructure of the red and white myotomal muscles of the crucian carp (Carassius Carassius) has been investigated. In the white fibres the amount of myofibrillar material fell from 89.6% to 70.7% of the total fibre volume whilst in the red fibres the fall was from 72.2% to 70.3%. The sarcoplasmic reticulum appeared to have become swollen during starvation in both fibre types. In the white fibres the terminal cisternae of some triads seem to have fused. The volume of the red fibres occupied by mitochondria was reduced from 16.2 % to 5.9 %. The concentration of mitochondria in the white fibres was too low to detect any quantitative changes. A marked reduction in the amount of euchromatin material was observed in most white fibre nuclei and many red fibre nuclei. Many of the ultrastructural changes noted in the present study can be correlated with biochemical changes known to occur in the red and white myotomal muscles of fish during starvation.
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  • 121
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    Cell & tissue research 137 (1973), S. 13-19 
    ISSN: 1432-0878
    Keywords: Urinary bladder (frog) ; Epithelial cells ; Osmotic pressure ; Oxytocin ; Water permeability ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The frog urinary bladder undergoes a marked increase in its water permeability when incubated in hypertonic media. Many similarities are found between this effect and the hydrosmotic action of antidiuretic hormone. The ultrastructural modifications of the epithelium observed under the influence of serosal hypertonicity (the intercellular spaces are dilated while the tight junctions remain closed) lead us to assume that the pathways of water movement across the epithelium could be the same in this case and in hydrosmotic response to the hormone. In contrast, when the mucosal medium is made hypertonic, the ultrastructure is differently altered: the intercellular spaces are closed, the tight junctions show small vesicles and numerous large vacuoles appearing in the cytoplasm.
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  • 122
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    Cell & tissue research 137 (1973), S. 361-374 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Saline-treatment ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neural lobes from rats which had been allowed to drink hypertonic saline for five days were examined electron microscopically and by bioassay of oxytocin levels. The profound changes in the ultrastructure were examined and the reversal of these changes in morphology was followed until the hormone levels returned to normal. The recovery of the gland as measured by the two parameters of structure and hormone content indicated that the morphological recovery apparently preceded the hormone level recovery, a factor which might be explained by continued release of hormone during the period of recovery.
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  • 123
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    Cell & tissue research 138 (1973), S. 315-326 
    ISSN: 1432-0878
    Keywords: Olfactory mucosa ; Frog ; Innervation ; Ultrastructure ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The olfactory mucosa of frog has been studied at an ultrastructural level to confirm previous light microscope observations in regard to the presence, in the sensory epithelium, of nerve fibres not belonging to the first cranial nerve proper. It has been observed that both myelinated and unmyelinated nerve fibres are present in the lamina propria and that eventually these fibres terminate inside the epithelium. Unmyelinated fibres usually contain dark core vesicles and similar content is seen in their intraepithelium terminals. Terminals containing only clear vesicles are also observed in the epithelium and they are believed to represent the terminals of the myelinated fibres. The significance of these ultrastructural findings is discussed in view of their functional meaning.
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  • 124
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    Cell & tissue research 138 (1973), S. 489-502 
    ISSN: 1432-0878
    Keywords: Chemoreceptor ; Crustacea ; Dendrite ; Cilia ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation of the aesthetasc hairs ofParagrapsus gaimardii differs slightly from that of other decapods described. Each outer flagellum bears from 160 to 170 aesthetascs each of which is innervated by approximately 130 bipolar sensory neurons. Distally the dendrite from each neuron bears two cilia at a ciliary junction. Each ciliary junction lies within an extracellular space and is situated below the base of the aesthetascs. The cilia have a 9+0 structure in their basal region. Just distally this structure becomes disorganized, the A- and B-subfibres separate and the dendrites increase in diameter. There is evidence for the branching of the cilia resulting in approximately 500 sensory endings per aesthetasc. No cellular processes are present in the distal 3/4 of the aesthetasc lumen. No pores were found in the aesthetasc walls which are “spongy” in appearance and permeable to crystal violet along the distal 3/4 of their length. The environmental significance of the “spongy” wall and the possible function of the cilia in early transmission of stimulus energy are discussed.
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  • 125
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    Cell & tissue research 138 (1973), S. 475-488 
    ISSN: 1432-0878
    Keywords: Synaptogenesis ; Spinal cord ; Chick embryo ; Coated vesicles ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Synaptogenesis was studied in 3, 4, 5 and 8 day embryos. A small number of synapses were located in the marginal zone near the motor region in 3–4 day embryos. At 5 days the number of synapses increased and synapses were also found within the motor region. At 8 days there was a large increase in the total number of synapses and most were found within the motor region. At this stage, for the first time, many knobs contained flattened synaptic vesicles. Synapses on the perikarya were rarely but occasionally observed both at the 5 and 8 day stages. A few synapses were located in the marginal zone near dorsal root entry at the 5 day stage and the number increased by the 8 day stage. Although this sequence of synaptic development resembles that found in the monkey fetus, differences in behavioral development between these two species indicate that descriptive relationships between synaptic and behavioral development must be made cautiously. Furthermore, evidence is presented which indicates that the junctional specialization is the first sign of a developing synapse and that coated vesicles, possibly derived from the Golgi apparatus, which are fused to the neural plasmalemma may be related to the initial formation of the junctional specialization.
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  • 126
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    Cell & tissue research 139 (1973), S. 201-215 
    ISSN: 1432-0878
    Keywords: Median eminence ; Mouse ; Ontogenesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les fibres nerveuses renfermant des vésicules granuleuses et des vésicules de type synaptique apparaissent dans l'éminence médiane de foetus de 14 jours. Dés le 18è jour foetal, de véritables terminaisons nerveuses sont au contact des capillaires du plexus intercalaire, constituant une charnière neurohémale. Les anses intrainfundibulaires commencent à pénétrer dans l'éminence médiane à la naissance mais ce n'est que chez des souris de 5 jours qu'elles deviennent très nombreuses. — Nous discuterons sur des critères morphologiques, de la possibilité d'un contrôle hypothalamique sur l'adénohypophyse avant la naissance.
    Notes: Summary Nerve fibers containing granular vesicles and vesicles closely resembling synaptic vesicles appear in the median eminence of 14 days old mouse fetuses. At 18th fetal day true nerve endings have been observed which are located close to the capillaries of the superficial plexus forming a neurovascular link. The capillary loops penetrate into the median eminence at the time of parturition but only in 5 days old mice they can be observed more frequently. — On the basis of the morphological observations presented the question is discussed whether the hypothalamus can influence pituitary hormone secretion before birth.
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  • 127
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    Cell & tissue research 140 (1973), S. 1-8 
    ISSN: 1432-0878
    Keywords: Ovary ; Smooth muscle ; Hamster ; Gerbil ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Smooth muscle-like cells are present in thecae externae, corpora lutea, and interstitial tissue of hamsters and gerbils. The smooth muscle-like cells, as examined by electron microscopy, are fusiform with central nuclei; the cytoplasm contains numerous myofilaments, dense bodies, micropinocytotic vesicles, and dense accumulations of glycogen-like particles. In addition to the smooth muscle-like cells, fibroblasts and cells that have characteristics of both fibroblasts and smooth muscle are located in the thecae externae of both species. There is no ultrastructural evidence of innervation in the theca folliculi, corpora lutea, or interstitial tissue of either species. A possible function for the smooth muscle-like cells is discussed.
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  • 128
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    Cell & tissue research 140 (1973), S. 217-234 
    ISSN: 1432-0878
    Keywords: Tentacles ; Electra pilosa ; Nerves ; Bielschowsky technique ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Le trajet des grands nerfs de la couronne tentaculaire et la structure du collier nerveux péripharyngien dont ils se détachent, ont été précisés chez Electra pilosa par des imprégnations argentiques in toto selon la technique de Bielschowsky et par une étude d'ultrastructure. Chaque tentacule est innervé par quatre faisceaux nerveux, dépourvus d'envelope gliale, qui courent entre l'épithélium et l'assise collagène qui délimite le canal tentaculaire interne; trois sont rassemblés sous les trois rangées cellulaires épithéliales de l'arête orale du tentacule et le quatrième est médian-dorsal. Les cellules épithéliales orales-latérales, par leur forme pédonculée, par la densité de leur cytoplasme, par leur cil unique et par leur relation topographique et cytologique avec les nerfs tentaculaires sous-jacents, présentent des adaptations structurales telles qu'il parait probable qu'elles assurent une fonction tactile. L'examen du collier péripharyngien montre son caractère organisé et la complexité des connexions qui coordonnent l'ensemble des tentacules et relient le lophophore à d'autres secteurs de l'innervation.
    Notes: Summary The pathway of the tentacle nerves and the organisation of the peripharyngial nervous belt from which they arise, have been studied in Electra pilosa by silver stained whole mounts (Bielschowsky technique), and by ultrastructural investigation. Each tentacle is innervated by four nervous fascicles without any differentiated glial sheath, running between the epithelium and the collagen layer which surrounds the muscles and the peritoneal cells in the internal tentacle canal. Three nerves are gathered underneath the three rows of epithelial cells forming the oral edge of the tentacle. The fourth nerve is in medio-dorsal location. The oral epithelial cells show such ultrastructural adaptations in their general shape, in the density of their cytoplasm, in their ciliary apparatus reduced to a single cilium and in their close topographical and cytological relationship with the underlying tentacle nerves that it seems most probable they have a tactile function. The analysis of the pattern of the peripharyngial nervous belt shows a precise organisation and the intrication of the connections which coordinate the tentacles and link the lophophore set to other pathways of general innervation.
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  • 129
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    Cell & tissue research 140 (1973), S. 169-175 
    ISSN: 1432-0878
    Keywords: Fat body ; Housefly ; Aging ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fat body of the adult housefly is composed of two types of cells, the lipid-and glycogen-rich fat body cells and the oenocytes. A comparison of the fine structure of the abdominal fat body in 4-day old and 31–35 day old male houseflies indicated an increase in lipid and a decrease in glycogen content in the fat body cells of old flies. Oenocytes of old flies exhibit deteriorative alterations with an accumulation of secondary lysosomes. Both fat body cells and oenocytes in senile flies are ingested by hemocytes.
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  • 130
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    Cell & tissue research 140 (1973), S. 309-314 
    ISSN: 1432-0878
    Keywords: Pituitary Gland ; Rat ; Somatotropin ; Cellular Response ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The response of somatotrophs to large doses of purified bovine growth hormone was examined in uninephrectomized rats drinking 1% sodium chloride in an attempt to prolong the action of the hormone. Growth hormone produced a triphasic response in the ultrastructure of somatotrophs. Uninephrectomy and salt alone induced no changes in somatotrophs as compared to unoperated animals consuming tap water. In the first phase (3 days) the cross sectional area of the cell increased, the size of the largest granule per cell as well as the number of granules per cell increased significantly. All these parameters then reached control level after 7 days of injections during a second phase. Suppression of somatotrophs by exogenous growth hormone was evident by 16 days (third phase) when the area of the cell, the size of the largest secretory granule as well as the number of granules per cell all decreased significantly. Somatotrophs apparently did not react to suppression by a lysosomal mechanism inasmuch as no increase in the number of lysosome-derived structures was seen even at 16 days.
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  • 131
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    Cell & tissue research 141 (1973), S. 319-330 
    ISSN: 1432-0878
    Keywords: Gonadal wall ; Holothuroidea (Leptosynapta clarki) ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The holothurian testes (as well as ovary) consists of three layers arranged concentrically around a central lumen which contains developing germ cells. The outer coelomic layer measuring 6 μ in thickness contains ciliated squamous epithelial cells, smooth muscle processes, nerve tracts, and occasional pigment cells. Interior to the outer layer is a haemal sinus measuring about 3 μ and consisting of haemal fluid composed of collagenous fibers and electron dense particles. Coelomocytes are embedded in this extracellular fluid matrix. The inner germinal layer, measuring 9 μ at the thickest regions consists of germinal cells, squamous epithelial cells, and coelomocytes. Occasional coelomocytes within the haemal sinus and germinal layer of the testicular wall contain spermatids enclosed within cytoplasmic vacuoles, suggesting phagocytosis as one of their cellular functions.
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  • 132
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    Cell & tissue research 142 (1973), S. 171-192 
    ISSN: 1432-0878
    Keywords: Spermiogenesis ; Teleost ; Albula vulpes ; Flagella ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé La jeune spermatide possède un noyau arrondi, un diplosome proche de la membrane cellulaire auquel sont associées des formations paracentriolaires; une mitochondrie unique est disposée entre le diplosome et le noyau. Au cours de l'évolution de la spermatide, le noyau s'allonge latéralement, son grand axe étant perpendiculaire à l'axe flagellaire; la mitochondrie migre à l'extrémité latérale du noyau; le centriole distal donne un flagelle de type 9+0; le centriole proximal se prolonge le long du noyau puis sort de la cellule sous la forme d'un pseudo-flagelle. Le prolongement centriolaire est constitué de triplets classiques et de doublets d'un type particulier que nous avons appelés «doublets A–C». Les auteurs signalent la similitude des spermatozoïdes de cet Elopiforme avec les spermatozoïdes d'Anguilliformes ce qui serait en faveur de la proposition de Greenwood et al. de rassembler ces téléostéens dans le super-ordre des Elopomorphes.
    Notes: Summary The early spermatid possesses a round nucleus and a diplosome which is close to the cellular membrane and with which paracentriolar formations are associated; a sole mitochondrion is located between the diplosome and the nucleus. During the spermatid evolution, the nucleus is laterally elongated, its main axis being perpendicular to the flagellar axis; the mitochondrion migrates towards the lateral end of the nucleus; the distal centriole is extended along the nucleus, then leaves the cell as a pseudoflagellum. This centriolar extension is made up of regular triplets and of a particular type of doublets that we have called “A–C doublets“. The authors call attention to the similarity between the spermatozoa of this Elopiforme and the spermatozoa of the Anguilliformes. This observation favours Greenwood et al.'s proposition, to place these teleost into the super-order of Elopomorpha.
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    Cell & tissue research 141 (1973), S. 469-478 
    ISSN: 1432-0878
    Keywords: Microsporida ; Nosema apis ; Developing spore ; Freeze-etching ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The mature spore possesses a thick spore coat and a particle-bearing spore membrane. The highly laminated polaroplast membranes are located at the anterior pole of the spore. Close to its base, the polar filament is surrounded by the polaroplast membrane. The polar filament runs spirally towards the posterior pole of the spore. A large portion of the polar filament is arranged in two layers. A similar arrangement was also observed in immature spores and in the sporoblast stage, although it was not so orderly arranged in the latter. The developing polaroplast membrane was observed in the immature spore, but not in the sporoblast. The sporoblast wall is much thinner than the spore coat, but has the same texture. Endoplasmic reticulum is the most prominent cytoplasmic organelle in the developing stages of Nosema apis. Porous nuclear envelopes are also observed in developing stages. The role of the endoplasmic reticulum in the formation of the polar filament, polaroplast and spore coat, and the function of the spore membrane, are discussed.
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  • 134
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    Keywords: Pars tuberalis ; Rat ; Development ; Secretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of the pars tuberalis was studied in the rat fetus from 13 days of gestation to 6 weeks after birth. After the closure of Rathke's pouch, the pars tuberalis anlage is clearly distinguishable from the anlagen of the partes intermedia and distalis. It comprises the entire basal portion of the adenohypophysial anlage; the limit between the anlagen of the pars tuberalis and the pars distalis is defined by Atwell's recess, i.e. the pathway taken by the hypophysial vessels coming from the vascular plexus of the median eminence. At 14 days the pars tuberalis cells are characterized by the presence of glycogen which persists in the adult. Their secretory differentiation (elaboration of granules with a diameter of 100–120 nm) is obvious at 15 days of gestation. It therefore, clearly precedes that of the other hypophysial cell types. Its functional differentiation takes place well before its adhesion to the primary vascular plexus of the portal system. Cystic formations appear just before birth in the pars tuberalis, much later than those of the pars distalis. These observations on the development of the pars tuberalis, together with previous observations on the adult PT in various species, showing that the specific glandular cells of the pars tuberalis are cytologically different from all known adenohypophysial cell types, seem to indicate a specific endocrine function of this lobe.
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  • 135
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    Cell & tissue research 143 (1973), S. 107-116 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Pituicytes ; Organotypic culture ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neural lobes of adult rats have been explanted and organ-cultured for 5–10 days. While perivascular cells and neurosecretory fibers undergo a progressive degeneration, scattered pituicyte-like cells are observed mostly associated with each other in number of two or three cells for group. Cultured pituicytes are quite similar to in vivo pituicytes except for some particular features as the shape of the nucleus and the number of dense bodies. Furthermore they share with the in vivo pituicytes the phagocytic capacity which appears even increased as far as neurosecretory fibers are concerned. Finally, degenerating pituicytes and free lipid droplets are observed in the intercellular spaces: the significance of these facts is discussed and tentatively interpreted. The organotypic culture of the neural lobe seems to represent an experimental model useful to obtain a relatively pure population of pituicytes.
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    Cell & tissue research 143 (1973), S. 169-182 
    ISSN: 1432-0878
    Keywords: Insecta Tysanura Machilida ; Protrusible (coxal) vesicles ; Water absorption ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les Machilides présentent une série de vésicules abdominales paires, sous forme de sacs exsertiles capables d'absorber l'eau d'un film liquide. Les coupes histologiques montrent qu'une partie de la paroi de ces vésicules est faite d'un épithélium particulier revêtu d'une intima cuticulaire plus épaisse que celle de l'épithelium banal. La microscopie électronique permet de préciser la structure des cellules absorbantes qui sont caractérisés essentiellement par des microvillosités apicales et de profondes invaginations de la membrane plasmique basale associées à des mitochondries allongées. Une comparison est faite avec d'autres types de cellules absorbantes connues chez les Arthropodes, notamment dans le rectum. Grâce à leurs vésicules abdominales, les Thysanoures possèdent des organes originaux jouant un rôle important dans l'équilibre hydrique de ces insectes.
    Notes: Summary The Machilida are endowed with several abdominal vesicles which are protrusible sacs capable of absorbing water from the substrate surface. Histology shows that a part of their outer wall consists of a particular epithelium covered by a cuticular intima, which is thicker than the intima of the common epithelium. The absorbing cells are electronmicroscopically characterized by apical microvilli and deep infoldings of the basal plasma membrane which are associated with mitochondria. A comparison is drawn with other types of absorbing cells already known, especially with those in the rectum of insects. Thanks to their abdominal vesicles, the Thysanura possess unique organs which play an important role in the control of their water balance.
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    Cell & tissue research 143 (1973), S. 183-206 
    ISSN: 1432-0878
    Keywords: Sensilla ; Olfaction ; Dictyoptera (insect) ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les organes sensoriels du scape et du pédicelle sont essentiellement propriocepteurs. Le fouet est très riche en chimiorécepteurs (plus de 100000) mais chez Periplaneta et Blatta, on observe un net dimorphisme sexuel qui n'existe pas chez Blaberus. La relation entre un tel dimorphisme et la perception des phéromones sexuelles est discutée. L'ultrastructure des trois principaux types de sensilles est décrite: Ce sont des grandes soies gustatives et mécanoréceptrices, des petites soies olfactives à paroi mince et percée de pores et de tubules qui sont innervées par un ou deux neurones, des petites soies olfactives à paroi épaisse et striée qui contiennent toujours quatre neurones. L'étude électrophysiologique préliminaire confirme les résultats ci dessus en ce qui concerne le rôle des sensilles: La phéromone grégaire peut être perçue au niveau de certaines petites soies olfactives striées.
    Notes: Summary The antennae of cockroaches were studied with both scanning and transmission electron microscope. The sense organs of the scape and pedicel are essentially proprioceptors. The chemoreceptors are very numerous on the flagellum (more than 100000) but in the case of Periplaneta and Blatta, a significant sexuel dimorphism is noticed. Such a dimorphism does not exist in Blaberus and its relation with the perception of the sexual attractants is discussed. Three principal sense organs of Blaberus are described: big thick walled hairs with gustatory and mechanoreceptive function; thin walled olfactory hairs with pore-tubules innervated by one or two neurons; thick walled grooved hairs with four neurons and olfactory function. Special attention was given to the secretory aspect of the accessory cells in the olfactory sensilla. A preliminary electrophysiological investigation confirms the above mentioned functional interpretations. The gregarious pheromone seems to be perceived by some little thick walled grooved hairs.
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  • 138
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    Cell & tissue research 143 (1973), S. 387-407 
    ISSN: 1432-0878
    Keywords: Oogenesis ; Urodela ; Yolk-formation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Oogenesis was studied in adult Triturus vulgaris (Urodela) with the electron microscope. The oocytes investigated ranged between 50 μm and 1600 μm in diameter. Two types of yolk platelet formation were found. Since both types involve the incorporation of high numbers of pinocytotic vesicles they are believed to be of an extraoocytic origin. On the basis of the order of their appearance they were named primary and secondary yolk. Five different types of vesicles were found, which participate in a variety of activities, such as yolk formation and the formation of the Golgi apparatus. They originate from four different sources, namely the nuclear membrane, the cytoplasm in connection with ribosome-like particles, the Golgi apparatus and the plasma membrane through pinocytosis. The results obtained were discussed especially with respect to differences found between the anura and the urodela, such as the presence or absence of cortical granules or equivalent structures.
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  • 139
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    Cell & tissue research 143 (1973), S. 439-449 
    ISSN: 1432-0878
    Keywords: Trout ; Gills ; Lamellae ; Chloride cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Scanning electron micrographs of gill tissue from rainbow trout fixed with 50% glutaraldehyde revealed the presence of microridges on surfaces of epithelial cells of the secondary lamellae. These microridges vary in length from 1 to 7 μ, with a mean height of 0.75 μ. Calculations show that they increase the total lamellar epithelial surface area approximately 2.5 fold. Mucus secreting cells are present on the body of the filament and on secondary lamellae. Chloride cells are located primarily in the interlamellae filamental epithelium and on the basal area of lamellae. Extensions of the chloride cell epithelium are microvillous in nature and their height is only slightly greater than that of the microridges of typical lamellar epithelial cells. A reduction in number or complete absence of microvilli on chloride cells appeared to be related to degenerative changes in these cells observed in transmission electron micrographs. Non secretory interlamellae filamental epithelial cells have microridges of very attenuated lengths.
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  • 140
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Membranes ; Exocytosis ; Ultrastructure ; Freeze-fracturing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Posterior pituitary glands from normal rats, and rats which had been deprived of water for varying periods, were examined by the freeze-fracture method. This technique reveals large areas of the nerve cell membrane. Images consistent with exocytosis as the mechanism of release of the neurohypophysial hormones were observed. These modifications were most numerous after the rat had been starved of water for 2 days. In normal rats, the large number of neurosecretory granules within the nerve fibres caused a bulging of the nerve cell membrane. The “bulges” disappeared 2 days after removal of drinking water. Regions of the membrane displaying “bulges” were characterised by the absence of the typical membrane-associated particles. It is postulated that the close proximity of the neurosecretory granules to the nerve cell membrane may result in rapid fusion of the neurosecretory granules on stimulation of the gland. The change in properties of the nerve cell membrane overlying the neurosecretory granules, as suggested by the loss of membrane-associated particles, may represent a change in the structure of the membrane to a form which is more favourable for fusion.
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  • 141
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    Cell & tissue research 137 (1973), S. 541-551 
    ISSN: 1432-0878
    Keywords: Muscles ; Insects ; Extracellular substance ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Im Stroma von Aorta und Retrocerebralkomplex sowie von verschiedenen Muskeln (Oberschenkel-, Mitteldarm-, Speicheldrüsen-, Samenleiter- und Eileitermuskeln), jedoch nicht im Stroma der Flugmuskulatur und des Herzschlauches, kommt eine fibrillär strukturierte Substanz (X-Substanz) von außerordentlich hoher Elektronendichte vor. In der Aorta, wo die größten Mengen an X-Substanz gefunden wurden, tritt besonders in den Muskelzellen älterer Tiere im Sarcoplasma und an der Plasmamembran eine körnige Substanz mittlerer Elektronendichte auf, welche auf Grund morphologischer Ähnlichkeit als Z-Material gedeutet wurde. Offenbar entsteht die X-Substanz, die in ihrer typischen Erscheinungsform nur extrazellulär beobachtet wurde, aus diesem Material. Da alte Tiere mehr X-Substanz aufweisen als jüngere, scheint es sich um die Abscheidung eines Altersprodukts zu handeln. Herkunft und Aussehen lassen ein langkettiges Protein vermuten. Muskeln, in denen X-Substanz vorkommt, enthalten auch viele Axone mit Neurosekreten; jedoch lassen sich bislang keine näheren Beziehungen zwischen diesen beiden Faktoren herstellen. Die X-Substanz wird offensichtlich vom Stroma weitertransportiert und wahrscheinlich von Blutzellen aufgenommen.
    Notes: Summary A fibrous substance (X substance) of exceptionally high electron density is found in the stroma of aorta, retrocerebral complex, and several muscles (leg, midgut, salivary glands, vas deferens and oviduct), but not in the stroma of flight muscles and heart. The aorta, where the largest amount of X substance occurs, shows within the muscle cells, especially of older animals, a granular substance of moderate electron density in the sarcoplasm and adjacent to the plasma membrane. On account of its morphological similarity this material is considered as Z material. The X substance, which in its typical appearance was seen only extracellularly, seems to be derived from this granular Z material. Since old animals show more X substance than younger ones, it appears to be an aging product. Its origin and appearance point to a protein with long chain structure. Muscles containing much X substance show many neurosecretory fibers. However, no tangible relationship between these two parameters has been established. The X substance is evidently transported by the stroma and probably taken up by hemocytes.
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  • 142
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    Keywords: Heart ; Rabbit ; Sinuatrial node ; Sinuatrial ring bundle ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cells of the sinuatrial ring bundle are smaller than the ordinary myocardial cells; they have a regular outline and a large content of myofibrils exhibiting distinct H-bands and M-lines. Rudimentary T-tubules are found. The cells are connected by frequent nexus junctions, desmosomes and regions of interfibrillar contact, both on the well developed intercalated discs and at the periphery of the cells. The cells in the cauda of the sinus node, which extends alongside the crista terminalis together with the right branch of the sinuatrial ring bundle, are irregularly outlined and have a highly variable diameter (1–10 μm). They occur in clusters of closely packed cells. The content of myofibrils is sparse and the fibrils exhibit no M-lines and only weak H-bands. No T-tubules are found. The cells are not connected by intercalated discs and no nexus junctions are found. Both tissues contain unmyelinated nerves and nerve fibres. Varicosities with mitochondria and vesicles are found in close apposition to the muscle cells.
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  • 143
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    Cell & tissue research 138 (1973), S. 523-544 
    ISSN: 1432-0878
    Keywords: Ovary ; Mink ; Lutein cells ; Plasma progesterone ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the lutein cells in the mink throughout pregnancy and the regression periodpost partum is described. To correlate the fine structure with the changes in the peripheral plasma progesterone levels, the concentrations of progesterone were measured by a rapid competitive protein-binding assay. Even during the delay period (e.g. as long the plasma progesterone levels remain at the basal level, 〈8ng/ml), the lutein cells in the mink exhibit structural criteria of functional activity. However, the increase in progesterone secretion is accompanied by some morphological transformations, characterized by the presence of more and more small dense homogenous bodies in the cytoplasm, which become irregular and scalloped during the stage with maximum release of progesterone. At this stage the agranular endoplasmic reticulum is often cisternal or vesicular. During the decline of the progesterone levels, typical and moderate electron-dense lipid droplets are found increasingly more within the lutein cells. The expanded agranular ER is now more sparse, while the granular ER becomes more pronounced, often forming parallel arrays. During this phase the mitochondria become elongated, dumb-bell, or cup shaped. After parturition the corpora lutea consist of cells in various stages of degeneration. At day 14post partum only a few lutein cells are still identifiable. Evidently the observed morphological changes take place in the lutein cells during the life span of corpora lutea. This feature lends further support to the concept that the mink lutein cells are steroid-producing cells and furthermore, that the corpora lutea may be the main sites of gestagen production during pregnancy.
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  • 144
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    Keywords: Gill ; Gammarus oceanicus ; Salinity acclimation ; Ultrastructure ; Mitochondria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Acclimation to low salinity induces changes in the ultrastructure of the gill cells of the marine euryhaline amphipod, Gammarus oceanicus. The gills are composed of a single cell type. In 100% artificial sea water, these cells contain moderate numbers of mitochondria which are randomly distributed in the cytoplasm. The plasma membrane is extensively invaginated at the apical, lateral, and basal surfaces. Acclimation to 20% artificial sea water induces a further invagination at the apical cell membrane to form an elaborate apical labyrinth. The extracellular spaces between the folds in the basal cell membrane dilate to 1500 Å or more. Mitochondria are more abundant and in many cells they undergo a change in conformation. The mitochondria are crowded into thin leaflets of cytoplasm between the dilated basal invaginations or into the narrow space between apical and basal cell membranes. Consequently, they lie in close contact with the plasma membrane over much of their surface.
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  • 145
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    Cell & tissue research 139 (1973), S. 351-368 
    ISSN: 1432-0878
    Keywords: Lateral giant cells ; Dorsal giant fibres ; Earthworm, Lumbricus terrestris L. ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Feinstruktur der segmental angeordneten Somata der dorsalen Riesenfasern im Bauchmark des Regenwurms Lumbricus terrestris L. (Günther, 1969) wird beschrieben und mit der Struktur anderer Neuronen von Vertebraten und Evertebraten verglichen. Die paarigen lateralen Riesenzellen (LRZ) sind im Gegensatz zu der unpaaren medianen Riesenzelle (MRZ) häufig multipolare Neuronen, die bis zu vier Faserfortsätze aufweisen können. Das perikaryale Cytoplasma zeigt helle und dunkle Areale. Organellen und andere Zelleinschlüsse finden sich ganz überwiegend in den dunklen osmiophilen Zonen und lassen regelmäßig eine bestimmte Anordnung erkennen. So ist häufig eine ringförmige Verteilung von Golgi-Feldern um den gelappten Kern vorhanden. Mitochondrien sind häufig in einem typischen „Axonhügel-Komplex“ angeordnet. Freie Ribosomen dominieren gegenüber membrangebundenen. Diese Neuronen sind reich an Glykogen, das oftmals ausgedehnte Felder einnimmt. Vereinzelt weisen die LRZ Faser-Soma-Synapsen auf.
    Notes: Summary The structure of the segmentally arranged somata of the dorsal giant fibres Günther, 1969) in the ventral nerve cord of the earthworms Lumbricus terrestris L., is described. These neurones are compared with other neurones of invertebrates and vertebrates. The paired lateral giant cells (LGC) are often multipolar in contrast to the single unipolar median giant cell (MGC). Up to four fibres originate from each LGC. The dotted appearance of both these neurones (clear and dark perikaryal areas) is due to the regular distribution of osmiophilic strands of cytoplasm containing the majority of organells and other inclusions (e.g. endoplasmatic reticulum and ribosomes). The majority of ribosomes are not associated with membranes but are found scattered freely in the cytoplasm. A typical “axon hillock” with an accumulation of mitochondria is often found. The cells show large deposits of glycogen. Some of the LGC-somata have synaptic contacts.
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  • 146
    ISSN: 1432-0878
    Keywords: Leydig cells ; Pekin Duck ; Testosterone ; Seasonal cycle ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'ultrastructure des cellules de Leydig et des cellules de Sertoli du testicule du Canard Pékin a été étudiée au cours de la phase printanière du cycle sexuel, soit de janvier à juillet. Parallèlement on a effectué chez les mêemes animaux la recherche histochimique de la Δ5-3 β-hydroxystéroïdedeshydrogénase (Δ5-3 β-HSDH) ainsi que le dosage, par chromatographie en phase gazeuse des stéroïdes androgènes dans le plasma veineux périphérique et dans le testicule. Les cellules de Leydig du Canard possèdent les organites cytoplasmiques spécifiques des cellules stéroïdogènes (reticulum lisse, mitochondries à crêtes tubulaires) ainsi que d'autres structures souvent rencontrées dans ce type cellulaire (microfilaments, vacuoles, granules denses). Les cellules de Sertoli contiennent un reticulum agranulaire moins développé que celui des cellules de Leydig et, très rarement, des mitochondries à crêtes tubulaires. Ces divers organites cytoplasmiques subissent un cycle saisonnier. La différenciation du reticulum lisse et des crêtes mitochondriales tubulaires commence en janvier et atteint son optimum en mars. Leur régression s'amorce en avril; d'abord accompagnée de structures dégénératives transitoires; elle conduit à la dispartion totale de ces organites en mait. Aucun indice de nécrose n'est observé dans ces cellules. Histochimiquement, une activité Δ5-3 β-HSDH est présente dans les cellules de Leydig et, à un degré moindre, dans les tubes séminifères. Son intensité varie au cours du cycle. La confrontation de l'étude morphologique avec les résultats des dosages hormonaux montre qu'il existe une bonne corrélation entre le développement puis la régression du reticulum lisse et des crêtes tubulaires des mitochondries ainsi que des critères histochimiques de la Δ5-3 β-HSDH d'une part et l'évolution de la testostérone plasmatique et testiculaire d'autre part. De plus on observe une augmentation du rapport testostérone/Δ4-androstènedione testiculaire parallèlement au développement des organites cytoplasmiques. Ces organites semblent donc bien impliqués dans la synthèse et la sécrétion de la testostérone chez le Canard.
    Notes: Summary Leydig and Sertoli cells of the testis of the Pekin duck were studied ultrastructurally during the spring phase of the sexual cycle, from January to July. Simultaneously, in the same animals, Δ5-3 β-hydroxysteroiddehydrogenase (Δ5-3 β-HSDH) activity was ascertained histochemically and androgenic steroids of the plasma and testes were assayed by gas-liquid chromatography. The Leydig cells of the duck possess cytoplasmic organelles specific to steroidogenic cells (smooth reticulum, tubular mitochondria) as well as other structures often found in this cell type (microfilaments, vacuoles, denses bodies). The Sertoli cells contain an agranular reticulum that is less developed than that of the Leydig cells, and rarely show mitochondria with tubular cristae. These various cytoplasmic organelles undergo a seasonal cycle. The differentiation of the smooth reticulum and the mitochondrial tubular cristae begins in January and reaches a maximum in March. They begin to regress in April, at first with transitory degenerative structures, and then by total disappearance of these organelles by May. No indication of necrosis is observed in the cells. Histochemically Δ5-3 β-HSDH activity is present in the Leydig cells, and to a slightly lesser degree in the seminiferous tubules. The intensity varies during the cycle. The comparison of the results of the morphological study with the hormone assays shows that a good correlation exists with the development and regression of the smooth endoplasmic reticulum and tubular cristae in the mitochondria, as well as the histochemical criteria of the Δ5-3 β-HSDH on one hand, and the levels of plasma and testicular testosterone on the other hand. In addition there is an increase in the ratio of testicular testosterone to Δ4-androstenedione which parallels the development of the cytoplasmic organelles. These organelles thus seem to be implicated in the synthesis and secretion of testosterone in the duck.
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  • 147
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    Cell & tissue research 146 (1973), S. 281-292 
    ISSN: 1432-0878
    Keywords: Eye ; Bird ; Pecten oculi ; Capillaries ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pecten oculi of the sparrow consists of capillaries, pigment cells and a superficial membrane. Because of the loose structure of the first two components broad intercellular spaces occur in the pecten. The capillary wall consists of endothelial cells and a perivascular membrane. The bodies of the endothelial cells are flattened, while the plasmalemma of both their surfaces (basal and luminal) is strongly folded and forms numerous microfolds with an average thickness of 700 Å. The height of the inner microfolds is 1.4–1.8 μm, the outer microfolds measure 1.3–1.6 μm. They lie densely packed side by side and are separated by recesses of the capillary lumen ca. 500 Å wide. Due to this the surface of the endothelial cell is increased by approximately 20-fold. The adjoining endothelial cells abut or overlap with margins, and are joined by the zonulae adherentes. Pigment cells form numerous processes and microvilli. Some rest on the capillary walls, while others penetrate the superficial membrane of the pecten or fill the intercellular spaces.
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  • 148
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    Cell & tissue research 146 (1973), S. 439-451 
    ISSN: 1432-0878
    Keywords: Sympathetic neurons ; Axon retraction ; Guanethidine ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Vasa deferentia of rats chronically treated with high doses of guanethidine sulphate (30 or 60 mg/Kg/day i.p.) were examined using electron microscopic, fluorescence histochemical and pharmacological techniques. Counts of the axon population in segments of the proximal (urethral) end of the vas deferens showed a reduction to approximately 55% and 35% in the number of axon profiles after treatment for one week with the two dose levels respectively. In the same period only a few cell bodies in the hypogastric ganglion (from which most of the adrenergic innervation of the vas deferens arises) reached the stage of terminal degeneration. Although many axons showed some abnormalities, the number of axons observed in terminal stages of degeneration in treated tissue did not exceed, at any stage examined, the very small numbers observed in control tissue. Organ bath studies showed that the contractile response to transmural stimulation was lost fastest at the distal (epididymal) end of the treated vas deferens. These results have led to the conclusion that, in contrast to the degeneration of adrenergic axons produced by surgery or 6-hydroxydopamine, the sympathectomy produced by guanethidinein vivo involves theretraction of adrenergic axons prior to complete degeneration of the cell bodies.
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  • 149
    ISSN: 1432-0878
    Keywords: Hypophysis ; Mouse, rat ; Pars intermedia, rostral zone ; Corticotrophic cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the mouse, the rostral zone of the pars intermedia is almost exclusively composed of typical corticotrophic cells. They are located around and even within the neural stalk, at the level of transition between stalk and neural lobe. In the rat, the corticotrophic cells of the rostral zone are found in scattered islets among the MSH producing cells, and also in the neural lobe. In both the rat and mouse, these cells are in direct contact with various types of nerve terminals. Synaptoid contacts with aminergic and neurosecretory nerve fibers are observed. Furthermore they are also closely related to the hypophysial portal vessels. Following adrenalectomy, the cells located in the neurohypophysis always react more intensely than tose in the rostral zone. The functional significance of these corticotrophic cells which are subject to both humoral and neural regulation remains as yet hypothetical. Their participation in neurogenic stress response seems probable.
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  • 150
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    Cell & tissue research 136 (1973), S. 121-137 
    ISSN: 1432-0878
    Keywords: Cheliceral gland ; Opiliones ; Enveloping cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Nemastoma dentigerum Canestrini besitzt als sekundäres männliches Geschlechtsmerkmal eine Apophyse auf dem ersten Chelicerenglied, die eine Drüse enthält. 2. Die einzelnen Drüsenzellen schließen sich jeweils zu Dreiergruppen zusammen, deren distales Ende immer von 3 Hüllzellen umfaßt wird. Diese 6 Zellen bilden eine funktionelle Einheit innerhalb des komplexen Drüsenorgans. Jede Drüsenzelle gliedert sich in 3 Abschnitte: 1. in den basalen kernhaltigen Teil, 2. in den mittleren sehr langen Drüsenzellschlauch und 3. in den distalen Kopf mit Mikrovilli-Becher. 3. An der Sekretion beteiligen sich 2 Zelltypen: die 3 Drüsenzellen und die innere Hüllzelle (H1). Das Sekret beider Zelltypen gelangt in ein gemeinsames Reservoir, das von H1 gebildet wird, und von dort durch Hämolymphdruck in den gewinkelten Cuticulin-Ausführkanal und auf die Außenseite der Apophyse. 4. Die Hüllzellen werden mit den 3 Hüllzellen der Haarsensillen von Insekten und Arachniden verglichen. Für H1 läßt sich eine gemeinsame Aufgabe nachweisen. Die beiden anderen Hüllzellen (H2 und H3) nehmen bei beiden Organen unterschiedliche Aufgaben wahr: Abscheidung von Haar und Balg (Haarsensillen) bzw. überwiegend Stützfunktion (Chelicerendrüse).
    Notes: Summary 1. Nemastoma dentigerum Canestrini possesses as a secondary male sex character an apophysis on the first member of chelicerae. The apophysis contains a gland. 2. The single gland cells always join as groups of three cells whose apices are embraced by three enveloping cells. These six cells operate as a unit within a complex gland organ. Every gland cell is divided into three parts: 1. a basal section containing the nucleus; 2. a central very long section of the gland cell tube, and 3. an apex of the gland cell with a cavity containing microvilli. 3. Two types of cells of a gland unit secrete: the gland cells proper and the inner enveloping cell (H1). Secretion of both types of cells flows in a common reservoir surrounded by H1 and further through the bent channel to the surface of the apophysis by pressure of hemolymph. 4. The enveloping cells are compared with those of hair sensilla of insects and arachnids. A common function of H1 in both organs is pointed out. Central (H2) and outer enveloping cell (H3) work in a different way: secretion of hair and follicle (hair sensilla) and probably only supporting function (cheliceral gland).
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  • 151
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    Cell & tissue research 136 (1973), S. 349-354 
    ISSN: 1432-0878
    Keywords: Intranuclear paracrystalline inclusions ; kidney ; Proximal tubule cells ; Canine ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Des inclusions intranucléaires paracristallines ont été mises en évidence dans les tubes proximaux de reins de chien. Ces inclusions sont constituées par une répétition régulière d'unités élémentaires microtubulaires de 85±15 Å de diamètre avec une périodicité de 120±20 Å. Elles ne sont jamais en contact ni avec le nucléole ni avec la membrane nucléaire. L'étude histochimique montre qu'il s'agit d'inclusions de nature protéique. Ces inclusions ont été observées à la fois dans les reins greffés (autogreffes) après conservation dans un perfusat artificiel (selon «Collins» ou «Perfudex») pendant 24 heures à 0°C et dans les reins normaux. N'étant jamais rencontrées au niveau de cellules rénales lésées, il ne semble pas que ces inclusions expriment une dégénérescence cellulaire.
    Notes: Summary The occurrence of intranuclear paracrystalline inclusions in proximal tubules of the canine kidney is described. These inclusions are composed of a regular repetition of microtubular elementary units of 85±15 Å thickness with a periodicity of 120±20 Å. They have no contact with the nucleolus or the nuclear membrane. Histochemical findings suggest that these inclusions may be proteinaceous. They are both observed in grafted kidneys (autografts) after conservation during 24 hours at 0°C in a synthetic solution (according to “Collins” or “Perfudex”) and in normal kidneys. There were no signs of degeneration in cells containing such inclusions; therefore, the possibility that these structures are of degenerative nature seems less probable.
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  • 152
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    Cell & tissue research 137 (1973), S. 223-250 
    ISSN: 1432-0878
    Keywords: Nervous system ; Ctenophores ; Nerve-net, Nervous concentration ; Synapses ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A subectodermal nerve-net is demonstrated in ten species of Ctenophores by means of either Methylene Blue vital staining or silver impregnation. There is no evidence of subendodermal nerve-net. The ectodermal nerve-net displays a characteristic polygonal pattern which is thought to result from morphogenetic events. Both bipolar and tripolar neurones occur. Three types of concentrations of nervous tissue are described: a) a high accumulation of nervous perikarya at the aboral sensory pole; b) a noticeable densification of the net along the eight meridional ciliary strands of every species, and around the lips of Beroidea; c) in the Cydippids Pleurobrachia and Hormiphora two thick strands of fibers and neurones interconnecting the aboral organ and the tentacles: the tentacular nerves. Ultrastructural evidence is given for the presence of nervous elements under and amidst ectodermal epithelial cells. Three features allow the recognition and characterization of neurites and neurones: a) numerous clear and/or granulated vesicles; b) microtubules in variable amounts; c) frequent and highly differentiated synaptic contacts. The very peculiar arrangement of the presynaptic elements is observed in all the species of Ctenophores so far studied. These synaptic contacts suggest chemical transmission in the nerve-net. On the basis of ultrastructural evidence the author refutes the nervous nature previously attributed to the ciliated cells of the meridional grooves. A parallel is drawn between nervous systems of Cnidaria and Ctenophora.
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    Cell & tissue research 138 (1973), S. 41-62 
    ISSN: 1432-0878
    Keywords: Germ cells ; Xenopus ; Spermatogenesis ; Chromatoid body ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of the male germ line in Xenopus laevis has been examined by electron microscopy. Findings have been compared to the parallel process in the female. Three structures unique to the germ line were found in both male and female cells: a fibrillar nuclear region free of DNA; largely proteinaceous masses of nuage material; and a chromatoid body. “Germ plasm” bodies of the egg and early embryo appear to represent a form of nuage material. The finding of a structure which can be identified as a chromatoid body in the female germ line is unique, as is its presence in sexually undifferentiated primordial germ cells. The chromatoid body in Xenopus, unlike that in mammals, does not persist in the spermatozoon. Instead, it dissociates into a series of coated vesicles during spermatogenesis. The chromosomal ultrastructure of meiotic prophase stages in Xenopus is similar in both sexes until diplotene, when male bivalents condense and enter meiotic metaphase instead of entering the extended lampbrush stage characteristic of the female. The multiple nucleoli present in gonia are lost at the onset of meiotic prophase, but no obvious mechanism for this process was observed.
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  • 154
    ISSN: 1432-0878
    Keywords: Protozoa ; Bacteria ; Association ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of Cyclidium, including the cilia, kinetosomes, pellicle, microtubules and kinetodesmal fibers is similar to that recorded for other ciliates. Of special interest is the attachment of rod-shaped bacteria within the longitudinally directed shallow surface folds of the protozoan. Both the bacteria and the surface of Cyclidium seem to possess an outer coating of a sticky substance which upon contact holds the bacteria to the protozoan. The bacteria appear to be attached by only a relatively small area of their surfaces. A dense substance appears within the alveolus of the pellicle at the regions of the attachment of the bacteria. The association of the organisms is probably a temporary one, and it is unknown whether either organism is benefited or harmed by the association. The position of the mitochondria in Cyclidium is unusual in that they all lie flattened against the inner membrane of the pellicle, usually in a position directly opposite to that of the attachment of the bacteria to the surface, thus being separated from the bacteria by only the outer cell membrane and the pellicle. Whether or not this close topographical relationship is of significance is unknown.
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  • 155
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    Cell & tissue research 139 (1973), S. 567-582 
    ISSN: 1432-0878
    Keywords: Compound Eye ; Apis mellifica ; Polarized light ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Die Ausrichtung der Rhabdome ist in der Bienenretina nicht konstant. 2. Die Anordnung der exzentrischen Zellen in der Bienenretina ist ebenfalls nicht konstant, und es läßt sich keine symmetrische Verteilung dieser Zellen nachweisen. 3. Die Morphologie der Retina wird im Hinblick auf die Orientierung der Honigbiene nach dem Polarisationsmuster des vom blauen Himmel reflektierten Lichtes diskutiert.
    Notes: Summary 1. The orientation of the rhabdoms shows no regularity within the retina of the honeybee. 2. The arrangement of the eccentric cells is also irregular within the retina of the honeybee. 3. The morphology of the retina is discussed regarding the ability of the honeybees to orient according to the pattern of the polarization of light reflected from the blue sky.
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  • 156
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    Cell & tissue research 140 (1973), S. 459-471 
    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Sockeye salmon ; Cell types ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the secretory cells of the adenohypophysis of juvenile sockeye salmon was investigated. Pituitary glands were collected from immature fish transferred experimentally to sea water and subsequently returned to fresh water. The rostral pars distalis contained three cell types: ACTH cells, prolactin cells, and non-secretory cells. The prolactin and non-secretory cells were joined together in the form of follicles by desmosomes and they both had cilia and microvilli projecting into the follicle lumen. Various follicular structures such as lumen, multivesicular structures, and peripheral basement membrane are discussed as possible sites of prolactin cell granule release. The columnar ACTH cells were found at the junction of the rostral pars distalis and the neurohypophysis. The cytoplasmic granules in these cells were characteristically separated from their limiting membrane by a clear space. Multivesicular structures were also found in association with this cell type. The caudal pars distalis also contained three cell types: one acidophil (putative somatotrop) and two basophils (putative thyrotrops and gonadotrops), all of which were similar to those described in adult fish. The pars intermedia contained only one cell type. They appeared to be active cells and were characterized by containing membrane-bounded granules similar to those found in the ACTH cells. Changes in ambient salinity had no apparent effect on any cell type described.
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  • 157
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    Cell & tissue research 143 (1973), S. 117-133 
    ISSN: 1432-0878
    Keywords: Nervous system ; Ctenophores ; Intra-mesogleal nervous system ; Synapses ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural evidence is given of the occurrence of nervous elements in the mesoglea of Ctenophores based on the presence of the typical synapses of this phylum. In Beroids, nervous fibers from the ectodermal nerve-net cross the epithelial basal membrane and run through the mesoglea; they are devoid of any ensheathing cell. These neurites build highly differentiated synapses upon the muscles and upon peculiar cells, tentatively named mesenchymal cells. In Cydippids, nerve fibers and nerve cell-bodies have been observed in the mesoglea of the tentacles. The mesogleal core of each tentacle contains mesenchymal cells and a thick strand of neurons and neurites, forming a kind of elongated ganglion. Neurites of either the axial neurones or the epithelial nerve-net neurones form numerous radial nerve strands across the tentacular muscles. Interneural, neuro-muscular and neuro-mesenchymal junctions are very frequent in the tentacle. As far as the organization of the mesoglea is concerned, the Ctenophora thus appear closer to Turbellaria than to Cnidaria.
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  • 158
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    Cell & tissue research 136 (1973), S. 461-477 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Acipenseridae ; Neurosecretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The neurohypophysis of sexually mature male and female Acipenser güldenstädti Brandt and Acipenser stellatus Pallas was studied light and electron microscopically. The recessus hypophysei lined with ependymal cells of two main types, “narrow” and “wide”, are in the center of the neurohypophysial “roots”. Processes from both cell types run radially to the basement membrane of the connective tissue layers abutting on the hypophysial intermediate lobe. Protrusions penetrating deep into the recessus hypophyseus are found in the apical parts of the “wide” cells. Pituicytes are rare in the neurohypophysis. The ultrastructure of both ependymal cell types and of the pituicytes is described. Nonmyelinated “Gomori-positive” (peptidergic) neurosecretory A1 and A2 type fibres and their terminals containing elementary neurosecretory granules (1400–1800 Å and 1000–1400 Å respectively) are the main structural elements of the neurohypophysis. Some “dark” and single myelinated neurosecretory fibres have been found. The adrenergic fibres (type B) were described earlier (Polenov et al., 1972a). The structural peculiarities of the neurohypophysis are discussed in functional and comparative-morphological terms.
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  • 159
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    Cell & tissue research 137 (1973), S. 271-280 
    ISSN: 1432-0878
    Keywords: Dental enamel ; Rat ; Ultrastructure ; Crystallography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Thin sections of rat incisor enamel were studied with the electron microscope. Fringe patterns having repeat periods in the range 3.1–8.2 Å were seen in individual enamel crystals. These images were interpreted as representing the resolution of corresponding planes in the hydroxyapatite crystal lattice. The lattice spacings and interplanar angles were identified by comparing the observations with available data derived from X-ray diffraction analysis.
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  • 160
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    Keywords: Hypophysis ; Pars distalis ; Lizard ; Gonadotropic cell ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Five categories of granulated cells were distinguished by their ultrastructural features, and quantitative analyses were made of the pars distalis cells in normal and castrated lizards. The gonadotropin-producing cell was identified on the basis of its uniform distribution in the gland as well as from cytological changes resulting from castration. The secretory granules of the gonadotropic cell vary in size (100–500 mμ) and density, and lipid bodies are commonly present. Following castration, the endoplasmic reticulum proliferates, forming many small, rough-surfaced, dilated cisternae which do not coalesce greatly as in other vertebrate species. Degranulation is accompanied by hypertrophy and hyperplasia of the mitochondria and by the appearance in the cytoplasm of conspicuous clusters of microfilaments. The designated gonadotropic cell was the only class of secretory cell showing consistent changes following three weeks of castration. In addition to the uniformly distributed gonadotrope cell, two secretory cells occur mainly in the rostral half of the gland, and two in the caudal half. Tentative identification of the cell types is discussed in the light of available information on the localization of the hormones in the pars distalis of this species.
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  • 161
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    Keywords: Touch receptors ; Sense organs ; Monogenean ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ventral surface of the posterior sucker of Entobdella soleae, a monogenean skin parasite of the sole Solea solea, is covered with more than 800 papillae ranging in size from 2.5–19 μm in diameter. The papillae are penetrated by nerves which double over themselves to form a stack-like array of lamellae running parallel to the surface of the haptor. No cilia or associated structures are present within these presumed sense organs and the papillae have no opening to the exterior. The much larger sucker papillae of a related species, E. hippoglossi, have been shown to have a similar ultrastructure. The possibility that the papillae may be contact receptors or strain receptors, providing proprioceptive information assisting the coordination of the attachment organ, is discussed and the papillae are compared with vertebrate touch receptors.
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  • 162
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    Cell & tissue research 137 (1973), S. 513-520 
    ISSN: 1432-0878
    Keywords: Nucleus infundibularis dorsalis ; Hypothalamus ; Xenopus laevis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the nucleus infundibularis dorsalis (NID) of the toad Xenopus laevis is described. The nucleus is paired and located in the caudal hypothalamus, dorso-laterally of the caudal end of the paraventricular organ (PVO), and bordering the dorsal wall of the recessus mamillaris. Two cell types can be identified. They are both bipolar and contain dense-core vesicles. Their apical processes protrude into the lumen of the recessus mamillaris, and therefore they are considered liquor-contacting neurons. Because of the Falck-positivity of these cells (Terlou and Ploemacher, 1973) it is assumed that the densecore vesicles contain monoamines. Both cell types probably are sensory cells, although the possibility of their being secretory active as well, cannot be excluded.
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  • 163
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    Cell & tissue research 138 (1973), S. 557-567 
    ISSN: 1432-0878
    Keywords: Thrombocytes ; Thrombosthenin ; ATP ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of glycerol extracted thrombocyte models was studied before and after incubation with ATP and under the influence of Salyrgan as inhibitor of contraction. The contractile system of the thrombocytes—thrombosthenin—consists of a spatial network of 50 Å wide thrombosthenin A and 100–120 Å wide thrombosthenin M filaments. At rest, the contractile system is arranged in a marginal zone. The ATP-induced contraction led to a concentric condensation of the network which resulted in a central cluster of cell organelles and at a later stage, disruption of the plasma membrane and release of the thrombocyte granules. All these changes which also occur during the formation of the hemostatic plug in vivo are therefore attributed to the reaction of the contractile protein.
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  • 164
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    Cell & tissue research 141 (1973), S. 545-560 
    ISSN: 1432-0878
    Keywords: Pineal gland (Rabbit) ; Light and dark pinealocytes ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the rabbit pineal gland a cortex and a medulla can be distinguished, based on the distribution pattern of two cell types. The medulla consists of so-called light and dark pinealocytes, whereas in the cortex only light ones occur. The cytological distinction between the two cell types is principally due to the exclusive presence of abundant pigment granules in the dark pinealocytes. The light pinealocytes have long offshoots. Their club-shaped terminals are crowded with smooth endoplasmic reticulum from which grey vesicles are pinched off. In the medulla, these offshoots run for the most part into the direction of blood vessels to terminate in close topographical relationship with dark pinealocytes which are mainly arranged around these vessels. The ultrastructure of both the light and the dark pinealocytes is described.
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  • 165
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    Cell & tissue research 144 (1973), S. 11-29 
    ISSN: 1432-0878
    Keywords: Spermatozoon ; Prosobranchia (Littorina) ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The filiform spermatozoon of Littorina contains a conical acrosome positioned anteriorly to the nucleus. The nucleus is essentially a tube of condensed chromatin surrounding the flagellar shaft and only the apical third is covered by a nuclear envelope. A structure resembling a basal body, which is either a modified proximal centriole, or a derivative of the distal centriole, terminates in a basal plate at the tip of the nucleus. Distally it gives rise to the nine outer flagellar doublets, which are continuous with the outer fibres of the distal centriole located 0.26 μ behind the “basal body”. Thus the “basal body” and distal centriole are lined up with each other and the axis of the flagellum. A supernumerary tubule connects the outer arm of the A subfibre of doublet 5 with the “basal body”. The flagellar shaft extends from the apex of the nucleus to the tip of the tail. In the mitochondrial region the plasmalemma fuses with the outer mitochondrial sheath to form a series of pores that connect the mitochondria directly with the external environment. A distinct joint separates the mitochondrial and tail regions enabling the tail to beat perpendicularly to the main flagellar axis. The last section of this paper is given to a discussion of sperm motility in the light of these structural observations.
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  • 166
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    Cell & tissue research 144 (1973), S. 139-152 
    ISSN: 1432-0878
    Keywords: CSF contacting axons ; Ependymal synapses ; Pineal organ ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Im Lumen des Pinealorgans können frei verlaufende, nackte Axone (Durchmesser 2000–7000 Å) beobachtet werden. Ihr Axoplasma enthält Mikrotubuli, Mitochondrien, synaptische (Durchmesser 350–450 Å) und granulierte Vesikel (Durchmesser 500–1500 Å). Bei Pleurodeles waltlii bilden die im Lumen des Pinealorgans verlaufenden Axone Synapsen auf der freien, apikalen Oberfläche der pinealen Ependymzellen. In den innervierten Ependymzellen kommen neben sonstigen Zytoplasmabestandteilen Myeloidkörper und Anhäufungen von Glykogengranula vor. Die Axone verlaufen am Innen- und Außenglied der Pinealozyten vorbei, können diese berühren, bilden aber dort keine Synapsen. Die auf den pinealen Ependymzellen nachgewiesenen Synapsen beweisen eine neuronale Kontrolle dieser Gliaelemente. Die Nervenfasern des pinealen Lumens wurden mit bekannten Liquorkontaktaxonen verglichen. Sie ähneln einander in ihrer Ultrastruktur und ihren synaptischen Verbindungen. Aus diesem Grunde und da bei den Amphibien das pineale Lumen mit dem 3. Ventrikel kommuniziert, werden die Axone des pinealen Lumens als Liquorkontaktaxone und als Glied des sogenannten Liquorkontakt-Axonsystems des Gehirns angesehen. Ferner wurden die pinealen Liquorkontaktaxone mit folgenden Nervenfasern und Endigungen verglichen, die im pinealen Gewebe vorkommen: 1) Axone, die große, granulierte Vesikel (Durchmesser 1300–1500 Å) enthalten und an den Dendriten von Nervenzellen endigen, welche zwischen den basalen Fortsätzen der Pinealozyten liegen; 2) Pinealozytenfortsätze, die synaptische Bänder enthalten und ebenfalls an diesen Neuronen Synapsen bilden; 3) die neurohormonalen, synaptischen Semidesmosomen von Pinealozytenfortsätzen an der Lamina basalis, die die bindegewebigen Räume der Pia mater vom eigentlichen Nervengewebe des Pinealorgans begrenzt: 4) die perivasalen, autonomen Nervenfasern der pialen Septen. Obwohl granulierte Vesikel verschiedener Durchmesser in allen diesen Terminalen vorhanden sind, stellten wir die größte, morphologische Ähnlichkeit zwischen den pinealen Liquorkontaktaxonen und denjenigen Nervenfasern fest, die große, granulierte Vesikel aufweisen und an den pinealen Neuronen axo-dendritische Synapsen bilden. Eine ähnliche Natur und Herkunft beider Axone werden angenommen.
    Notes: Summary Free-running, naked axons (diameter 2000 to 7000 Å) can be found in the lumen of the pineal organ. Their axoplasm contains microtubules, mitochondria as well as synaptic (diameter 350 to 450 Å) and granulated vesicles (diameter 500 to 1500 Å). In Pleurodeles waltlii, the axons in the pineal lumen form synapses on the free, apical surface of the pineal ependyma which is supplied with microvilli. In addition to usual cytoplasmic elements the innervated ependymal cells contain myeloid bodies and accumulations of glycogen granules. Without forming synapses these axons pass by and occasionally contact the inner and/or outer segments of the pinealocytes. The synapses found on the pineal ependymal cells furnish evidence of a neuronal control of these glial elements. The nerve fibers of the pineal lumen are being compared with known CSF contacting axons; they resemble one another in their ultrastructure and synaptic connections. Therefore and since in amphibians the pineal lumen communicates with the 3rd ventricle, the axons of the pineal lumen are considered to represent CSF contacting axons and to belong to the so-called CSF contacting axon system of the brain. In addition, the pineal CSF contacting axons are being compared with the following nerve fibers and terminals found in the pineal tissue: 1) axons containing large, granulated vesicles (diameter 1300 to 1500 Å) and terminating on the dendrites of nerve cells situated among the basal processes of the pinealocytes; 2) the synaptic ribbons-containing pinealocyte processes forming likewise synapses on the nerve cells; 3) the neurohormonal, synaptic semidesmosomes of pinealocytic processes on the lamina basalis separating the connective tissue spaces of the pia mater from the proper nervous tissue of the pineal organ; 4) the perivasal, autonomic nerve fibers of the pial septa. Though granulated vesicles of various diameters are present in all these terminals the greatest morphological similarity is found between the pineal CSF contacting axons and those nerve fibers containing large, granulated vesicles and forming axo-dendritic synapses on the pineal nerve cells. A similar nature and origin of both axons are suggested.
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    Cell & tissue research 144 (1973), S. 191-217 
    ISSN: 1432-0878
    Keywords: Nucleus infundibularis ventralis ; Hypothalamus ; Rana esculenta ; Gonadotropin releasing factor ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural evidence has been obtained for several nerve cells in the middle and posterior hypothalamus of Rana esculenta, which may be classified as neurosecretory cells. These cells belong to the nucleus infundibularis ventralis, being homologous to the nucleus infundibularis of higher vertebrates. According to the type of dense-core vesicles, two categories of neurosecretory cells were identified in the NIV, type Y and type Z cells. The morphology of these cells and the diameter of their dense-core vesicles suggests a peptidergic nature of the secretory product. Both cell types appeared as bipolar, liquor-contacting neurons, innervated by aminergic axons. The effects of castration and testosterone treatment on the Y cells of the NIV, as well as their localization in the caudal hypothalamus, suggest these cells to be involved in the regulation of the gonadotropic activity of the pars distalis. The presence in the zona externa of the median eminence of axon terminals containing the “Y type dense-core vesicles” is indicative of the release of their secretory product into the portal vessels.
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    Cell & tissue research 144 (1973), S. 453-466 
    ISSN: 1432-0878
    Keywords: Lacrimal gland ; Rat ; Duct system ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The duct system of the rat exorbital lacrimal gland consists of intercalated ducts, interlobular ducts and excretory ducts. The morphological changes from one type of duct to the next are gradual. At the light microscopical level this consists of a change from a bilaminar epithelium in the intercalated ducts to an epithelium, consisting of approximately three layers — which may be pseudostratified — in the excretory ducts. The basal layer of the intercalated ducts consists of myoepithelial cells, whereas the inner epithelial cells may have both a secretory and an electrolyte transporting function. The interlobular duct epithelium contains many cells with deep infoldings of the basolateral plasma membranes and associated mitochondria, suggesting a similar function to the striated duct epithelium in salivary glands. Numerous basal cells in this epithelium have tentatively been interpreted as unusual myoepithelial cells. Nerve terminals have been observed in the ductal epithelium.
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    Cell & tissue research 145 (1973), S. 447-458 
    ISSN: 1432-0878
    Keywords: Corpus allatum ; Oncopeltus fasciatus ; Larvae ; Imagines ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 1. The ultrastructure of the corpora allata of last larval instars and adults of Oncopeltus was studied. The unpaired gland undergoes submicroscopic alterations and shows signs of degradation in old animals. The organ is partly covered and penetrated by corpus cardiacum tissue. Axons with different types of neurosecretory granules form synaptoid contacts with the corpus allatum cells. 2. “Dark” and “light” gland cells can be differentiated on account of the degree of electron density. The former predominate during the last larval stage and in the young imago, the latter in mature males and females. It is highly probable that the “light” cells are the active (i.e. hormone producing) ones and the “dark” cells the inactive ones. 3. The active cells are characterized by rough endoplasmatic reticulum (often in whorls), small amounts of smooth endoplasmatic reticulum and many multivesicular bodies. Abundant free ribosomes, a not particularly well developed Golgi apparatus, dense bodies, and cytolysomes are present in active and inactive cells. 4. The nuclei contain one to four prominent and variously shaped nucleoli, which show differences between adult males and females with respect to their location in the nucleus. 5. The corpus allatum cells of Oncopeltus are obviously engaged in extensive protein synthesis. Tangible structural indications for the manufacture of juvenile hormone were not observed. Possible sites of hormone release are discussed.
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    Cell & tissue research 146 (1973), S. 155-165 
    ISSN: 1432-0878
    Keywords: Muscle ; Crayfish ; Synapse ; Degeneration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neuromuscular junctions, muscle fibers, and intramuscular nerve branches in crayfish opener muscles denervated for periods up to 368 days were examined with the electron microscope. The majority of the denervated muscles responded to stimulation of the isolated distal part of the motor axon with electrical activity and contractions. The neuromuscular junctions and muscle fibers appeared normal in such preparations: synapses and synaptic vesicles were present in the nerve terminals, and the organization of filaments and tubules in the muscle fibers was not distinguishable from that in normal muscles. In some preparations denervated for a long time, and in others denervated by tying the motor axon close to the muscle, the motor axons showed physiological and morphological evidence of degeneration. Synapses, when present in such preparations, showed few synaptic vesicles, which were often clumped. Muscle fibers showed signs of degeneration. These observations suggest that isolated distal motor axon segments can remain alive for at least a year, retaining normal structure. As long as the motor axon is viable, the muscle remains normal in appearance, but if the axon degenerates, the muscle becomes abnormal. A trophic interdependence between nerve and muscle is probably involved.
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  • 171
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    Keywords: Parathyroid ; Secretory cycle ; Winter frog ; Ultrastructure ; Pituitary homoimplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Parathyroid glands of winter frogs (Rana pipiens) were compared by light and electron microscopy with those of winter frogs homoimplanted with pituitary glands. Serum calcium levels of untreated and pituitary-implanted animals were compared also. Forty-eight hours after pituitary implantation, serum calcium is elevated from a mean winter value of 6.2 mg % to 9.3 mg % and, morphologically, the parathyroid gland appears to be stimulated with respect to secretory activity. Compared with parathyroids of untreated winter frogs, intercellular spaces are diminished after pituitary implantation and glandular parenchyma is composed of cells with closely apposed plasma membranes thrown into interdigitating folds. Dense core vesicles are present in the cytoplasm and, together with microtubules, are encountered near plasma membranes. Golgi lamellae contain electron dense material and exhibit budding of dense core vesicles. Neither myelinated multivesicular bodies, presumably cytolysosomes degrading unneeded parathormone and organelles, nor focal dilatations with myelination of Golgi lamellae are encountered in parathyroid cells of pituitary implanted frogs. Rough endoplasmic reticulum and mitochondria do not undergo marked changes in distribution or abundance after pituitary implantation, indicating that the synthetic aspects of the secretory process are little altered in untreated and treated animals. It is suggested that in addition to Ca++ a pituitary factor is involved in the seasonal changes in amphibian parathyroid structure and function.
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    Cell & tissue research 146 (1973), S. 207-221 
    ISSN: 1432-0878
    Keywords: Substantia nigra ; Rat ; Six bouton types ; Strio-nigral projection ; Bouton degeneration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The normal ultrastructure of rat substantia nigra was investigated. Special attention was paid to the different types of boutons, and the mode of termination of the striatonigral connection was examined. Two different types of nigra neurons with deep nuclear membrane indentations were observed. The synaptic organization of rat substantia nigra is very complex. Six types of boutons, with many characteristics, could be differentiated: pleomorphicvesicle boutons (40%), elongated-vesicle boutons (10%), small-round-vesicle boutons (10%), large-round-vesicle boutons (20%), “clear-terminal” (15%) and dense-core-vesicle boutons (about 5%). Vesicle-containing dendrites were observed entering dendro-dendritic synapses. One to four days after large unilateral striatal lesions were made, a great number of degenerating boutons were seen in the ipsilateral substantia nigra, while the contra-lateral substantia nigra was entirely free of degeneration. The newly defined pleomorphic-vesicle boutons were found almost exclusively in the process of degeneration. The neuronal origin of the other bouton types is discussed.
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    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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  • 174
    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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  • 175
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    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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  • 176
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    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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  • 177
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    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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  • 178
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    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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  • 179
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    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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  • 180
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    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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  • 181
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    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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  • 182
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    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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  • 183
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    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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  • 184
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    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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  • 185
    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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    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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    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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  • 188
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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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  • 189
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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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  • 190
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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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  • 191
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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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  • 192
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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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  • 193
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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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  • 194
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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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  • 195
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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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  • 196
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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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  • 197
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    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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    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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    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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    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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