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  • 2000-2004  (46)
  • 1975-1979  (1,153)
  • 1920-1924
  • Electron microscopy  (618)
  • Ultrastructure  (588)
  • 101
    Electronic Resource
    Electronic Resource
    Springer
    Archives of dermatological research 266 (1979), S. 187-196 
    ISSN: 1432-069X
    Keywords: Disseminated lipogranulomatosis ; Farber's disease ; Sphingolipidoses ; Ceramide ; Ultrastructure ; Disseminierte Lipogranulomatose ; M. Farber ; Sphingolipidosen ; Ceramid ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Eine elektronenmikroskopische Untersuchung von 2 Hautläsionen bei einem aus der Türkei stammenden 2jährigen Jungen mit disseminierter Lipogranulomatosis (Farber) zeigte curvilineare Körper in Fibroblasten, Histiocyten und Endothelzellen, flache Membrananordnungen in Fibroblasten und Endothelzellen und spindelartige Körper in Schwann-Zellen. In peripheren Lymphocyten fanden sich nur Veränderungen der Mitochondrien (Schwellung und aufgebrochene Cristae), jedoch keine Einschlußkörper. Die intracytoplasmatischen curvilinearen Körper waren zahlreich und leicht nachweisbar. Sie scheinen für den M. Farber spezifisch zu sein, und es wird vorgeschlagen, sie “Farber Körper” zu nennen. Die Diagnose dieser Ceramidspeicherkrankheit, in der das histologische Bild weitgehend unspezifisch ist, kann daher ultrastrukturell bestätigt werden.
    Notes: Summary An ultrastructural investigation of two cutaneous lesions in a two-year-old Turkish boy with disseminated lipogranulomatosis (Farber) revealed curvilinear bodies in fibroblasts, histiocytes, and endothelial cells; “elongated membranes” in fibroblasts and endothelial cells; “zebra bodies” in endothelial cells; and spindle-shaped bodies in Schwann cells. In peripheral lymphocytes only alterations of mitochondria (swelling and ruptured cristae) but no inclusion bodies were found. Curvilinear bodies were numerous and easily identifiable; they appear to be characteristic of Farber's disease, and naming them “Farber bodies” is proposed. The diagnosis of this ceramide storage disease, in which the histological examination is relatively unspecific, can therefore be confirmed ultrastructurally.
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  • 102
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    Springer
    Archives of dermatological research 266 (1979), S. 253-267 
    ISSN: 1432-069X
    Keywords: Kaposi's sarcoma ; Histochemistry ; Electron microscopy ; Venous capillary endothelium ; Angioblast ; Kaposi-Sarkom ; Histochemie ; Elektronenmikroskopie ; venöse Kapillarendothelien ; Angioblast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Histochemische und ultrastrukturelle Untersuchungen bei zwei Patienten mit Kaposi-Sarkom ergaben, daß die Spindelzellen die Merkmale von venösen Capillarendothelien aufweisen.
    Notes: Summary Histochemical and ultrastructural studies in two patients with Kaposi's sarcoma revealed that spindle cells have the pattern of venous capillary endothelium.
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  • 103
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    Springer
    Archives of dermatological research 266 (1979), S. 239-251 
    ISSN: 1432-069X
    Keywords: Cutaneous malignant B-cell lymphoma ; Ultrastructure ; Semithin sections ; Cutane maligne B-Zell Lymphome ; Ultrastruktur ; Semidünnschnitte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Achtzehn Fälle von cutanen B-Zell Lymphomen von niedrigem Malignitätsgrad (gesichert durch Enzymcytochemie und Immuncytologie) wurden morphologisch mittels Semidünn- und Dünnschnitten unter-sucht. Vier Typen mit einem charakteristischen Muster von verschiedenen lymphoiden Zellen wurden gefunden: (1) Der lymphocytische Typ, überwiegend aus kleinen Lymphocyten bestehend; (2) der lymphocytoide (zentrocytische oder prolymphocytische) Typ, bei dem neben kleinen auch mittelgroße Lymphocyten (mit und ohne geknitterten Zellkernen) erscheinen; (3) der lymphoplasmacytoide Typ, bei dem neben kleinen und mittelgroßen Lymphocyten lymphoide Zellen mit unterschiedlich ausgeprägten Differenzierungsmerkmalen von Plasmazellen zu finden sind; sowie (4) der zentroblastische-zentrocytische Typ. Hier sind neben kleinen und mittelgroßen Lymphocyten auch Zentroblasten zu beobachten. Insgesamt stimmen die hier erhobenen morphologischen Befunde gut mit entsprechenden nodalen malignen Lymphomen überein. Die Anwendung moderner Klassifikationen von non-Hodgkin Lymphomen, insbesondere die »Kiel-Klassifikation«, erscheint daher auch für die Hautlymphome gerechtfertigt. Dünn- und Semidünnschnitte eignen sich bei der Routinediagnostik von derartigen Krankheitsfällen, vor allem dann, wenn mit Paraffinschnitten keine klare diagnostische Einordnung erfolgen konnte.
    Notes: Summary Eighteen cases of low grade malignant B-cell lymphomas (confirmed through enzyme cytochemistry and immunocytology) were investigated morphologically using thin and semithin sections. Four types with a characteristic pattern of different lymphoid cells were found: (1) the lymphocytic type, predominantly consisting of small lymphocytes; (2) the lymphocytoid (centrocytic or prolymphocytic) type, in which in addition to small lymphocytes medium-sized lymphocytes (with or without cleaved nuclei) are found; (3) the lymphoplasmacytoid type, where lymphoid cells with different degrees of similarity to plasma cells are seen as well as small and medium-sized lymphocytes; and (4) the centroblastic-centrocytic type, in which centroblasts are present next to small and medium-sized lymphocytes. These findings correlate well with the morphological observations in low-grade malignant B-cell lymphomas of the lymph nodes. Therefore, the application of modern classifications of non-Hodgkin lymphomas, such as the “Kiel Classification”, to cutaneous lymphomas appears justified. Thin and semithin sections are particularly useful in suspected cases of cutaneous malignant lymphoma, in which paraffin sections did not allow the diagnosis to be established.
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  • 104
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    Archives of dermatological research 266 (1979), S. 295-310 
    ISSN: 1432-069X
    Keywords: Fibronectin ; Skin ; Basement membranes ; Immunohistochemistry ; Electron microscopy ; Fibronectin ; Haut ; Basalmembran ; Immunohistochemie ; Elektronenmikroskopie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Verteilung des extracellulären Glykoproteins Fibronectin im Haut- und Zungengewebe der Ratte wurde unter Verwendung von spezifischem Antiserum licht- und elektronenmikroskopisch mit Hilfe der Immunofluorescenz- und Immunoperoxidasemethoden untersucht. Aus den Ergebnissen schließen wir, daß Fibronectin weder in stabilen, differenzierten Gewebeteilen wie Talgdrüsen, Matrix, Mark, Rinde oder Cuticula des Haares oder der inneren und äußeren Haarwurzelscheide, noch in Geweben, in denen die Zellen zum Teil beweglich sind (z. B. Epidermis), vorkommt. Es ist aber charakteristisch für Zonen, wo Zellteilung in Berührung mit einem extracellulären Gerüst vor sich geht, wie z. B. an einer Basalmembran oder in lockerem Bindegewebe. Auffallende Beispiele waren die mit Follikelepithelien verbundene Hyalinmembran und Bindegewebsscheide, die unter Gefäßendothelzellen liegende Basalmembran, die Bindegewebe, welche die Nerven- und Muskelfaserbündel umgeben und durchsetzen und das Bindegewebe der Dermis. Im letzteren Falle war das Fibronectin oft mit Kollagenfasern eng verbunden. In der Basalmembran an der Grenze zwischen Dermis und Epidermis war Fibronectin an der Plasmamembran der basalen Zellen und im Gebiet der Lamina lucida zu finden. Es bestand kein Zusammenhang mit spezifischen Stellen der Zellen-Substrat-Adhäsion wie den Hemidesmosomen. Das endoplasmatische Reticulum der Fibroblaste ließ sich stark färben — ein Hinweis, daß diese Zellen einen wichtigen Ort der Synthese darstellen.
    Notes: Summary Specific antiserum was used to investigate the distribution of the extracellular glycoprotein, fibronectin, in rat skin and tongue tissue by light and electron microscopy with immunofluorescence and immunoperoxidase techniques. We conclude that fibronectin is absent from stable, differentiated parts of tissues, such as the sebaceous glands or the matrix, medulla, cortex, and cuticles of the hair and the inner and outer root sheaths, or even in tissues in which there is some cell movement, such as the epidermis. It is, however, characteristic of sites at which cell division is occurring in contact with an extracellular scaffolding, such as basement membrane or loose connective tissue. Conspicuous examples were in the glassy membrane and connective tissue sheath associated with the follicular epithelium, the basement membrane underlying vascular endothelial cells, the connective tissues surrounding and investing nerve and muscle fibre bundles, and the dermal connective tissue where fibronectin was often associated closely with collagen fibres. At the basement membrane of the dermal/epidermal junction, fibronectin occurred at the plasma membrane of the basal cells and in the lamina lucida area. There was no correlation with specific areas of cell-substrate adhesion, such as the hemidesmosomes. The endoplasmic reticulum of fibroblasts stained strongly suggesting that these cells represent a major site of synthesis.
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  • 105
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    Acta neuropathologica 48 (1979), S. 211-214 
    ISSN: 1432-0533
    Keywords: Medullomyoblastoma ; Desmoplastic medulloblastoma ; Teratoid ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of cerebellar medullomyoblastoma in a young boy was investigated by electron microscopy. The neuroectodermal component shows the characteristics of a desmoplastic medulloblastoma. The mesodermal component consists of more or less differentiated cross-striated muscle cells. Undifferentiated muscle cells are very similar to proliferated endothelial cells of blood vessels within the muscular component, so that an origin of this component from pluripotential endothelial cells of the vessel wall is suggested. This tumor is considered a malignant teratoid because of the derivation from two blastodermic layers and because of the midline localization in children suggesting a malformative origin.
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  • 106
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    Acta neuropathologica 48 (1979), S. 95-103 
    ISSN: 1432-0533
    Keywords: Schmidt-Lanterman incisures ; Electron microscopy ; Nerve crush ; Wallerian degeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The electron microscopy of changes at Schmidt-Lanterman incisures in Wallerian degeneration has been described only briefly previously. We have demonstrated that the changes up to 36 h after nerve crush are chiefly peri-incisural. At 12h and 24h ‘incisural dilatation’ consisted of an intraperiod line separation of peri-incisural myelin lamellae, which began among inner (adaxonal) lamellae extending later to outer (abaxonal) lamellae. The incisure itself showed little or no change. At 36 h, ovoid formation was apparent in most fibres. The sites of fibre cleavage to form ovoids occurred adjacent to incisures at the focal regions of myelin lamellae separation. Even within ovoids the incisures themselves remained intact at 36 h. The fine structural changes at incisures following nerve crush provide an understanding of the increased perceptibility of incisures by light microscopy during early Wallerian degeneration.
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  • 107
    ISSN: 1432-0533
    Keywords: Mucopolysaccharidosis II ; Prenatal diagnosis ; Electron microscopy ; Lysosomal storage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Light and electron microscopic findings in the nervous system of a 23-week-old fetus are reported, in which MPS II was diagnosed prenatally. The degrees of myelination and neuronal differentiation were similar as in a normal fetus of the same age. A storage of mucopolysaccharides in typical vacuolar inclusion bodies was present throughout the peripheral and central nervous system, mainly in cells of mesenchymal origin. “Zebra” bodies and granulo-membranous bodies, which are thought to represent secondary ganglioside accumulation were only found in the well developed neurons of the spinal cord and spinal ganglia, but not in the poorly developed neurons of the cerebellar and cerebral cortex. Mucopolysaccharide storage in endothelial cells of cerebral blood vessels precedes the appearance of lipid storage in cerebral neurons.
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  • 108
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    Acta neuropathologica 48 (1979), S. 219-221 
    ISSN: 1432-0533
    Keywords: Herpes simplex virus ; Organotypic nerve cell cultures ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In HSV-2 infected cultures, intranuclear tubule-like structures were found more commonly in fibroblasts and central nervous system (CNS) neurons than in oligodendrocytes, astrocytes, satellite and Schwann cells, but were found least often in peripheral neurons.
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  • 109
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    Archives of dermatological research 265 (1979), S. 195-206 
    ISSN: 1432-069X
    Keywords: Hyalinosis ; Electron microscopy ; Glycosaminoglycan ; Glycoprotein ; Cross-banded structure ; Schlüsselwörter ; Hyalinose ; Elektronenmikroskopie ; Glykosaminoglykan ; Glykoprotein ; Struktur mit Querstreifen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Systematisierte Hyalinose (Juvenile Hyaline Fibromatose) ist durch die hyalinisierten Hautefflorescenzen gekennzeichnet. Die elektronenmikroskopische Untersuchung eines hyalinisierten Hauttumors von einem 19jährigen Mann mit diesem Syndrom ergab, daß die Hyalinsubstanz sich aus den Rutheniumrot-positiven Ultrastrukturen des Glykosaminoglykans oder des Glykoproteins (d. h. Körnchen, Fäden und einer Struktur mit Querstreifen) und einigen dünnen Kollagenfibrillen zusammensetzte. Mit unserer neuen Rutheniumrotfärbung in der Kombination mit der Enzymverdauungsmethode wurde demonstriert, daß die Struktur mit Querstreifen und die Körnchen aus Chondroitinsulfat-Proteoglykan und/oder Glykoprotein besteht, und daß es sich bei der Struktur mit Querstreifen höchstwahrscheinlich um ein nichtkollagenes Aggregationsprodukt der Körnchen handelt, die eng an die parallel angeordneten, Hyaluronsäure-ähnlichen Fäden angelegt sind.
    Notes: Summary Systematic hyalinosis (juvenile hyaline fibromatosis) is characterized by hyalinized skin lesions. Electron microscopic examination of a hyalinized skin tumor from a 19-year-old man with this syndrome revealed that the hyaline was composed of ruthenium red-positive ultrastructures (granules, filaments, and a kind of cross-banded structure), indicating the presence of glycosaminoglycan or glycoprotein, and a small number of thin collagen fibrits. Using a new ruthenium red staining method combined with an enzymatic digestion procedure, it was demonstrated that the cross-banded structure and granules consisted of chondroitin sulfate-proteoglycan and/or glycoprotein, and that the cross-banded structure is probably a noncollageneous aggregate of the granules attached to the parallel-arranged filaments of hyaluronic acid-like nature.
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  • 110
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    Archives of dermatological research 264 (1979), S. 17-28 
    ISSN: 1432-069X
    Keywords: Malignant lymphoma ; Mycosis fungoides ; Sezary's syndrome ; Parapsoriasis en plaques ; Ultrastructure ; Semi-thin sections ; Maligne Lymphome ; Mykosis fungoides ; Sézary-Syndrom ; Parapsoriasis en plaques ; Ultrastruktur ; Semi-Dünnschnitt-Technik
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Semi-Dünnschnitte erlauben eine bessere morphologische Differenzierung von lymphoiden Zellen als Paraffinschnitte. Zur Prüfung ihrer möglichen Bedeutung bei der Diagnostik von kutanen T-Zell-Lymphomen wurden folgende Untersuchungen durchgeführt: Lymphoide Zellen im cellulären Infiltrat von Hautläsionen bei Mykosis fungoides (11 Fälle), Sézary-Syndrom (9 Fälle) und Parapsoriasis en plaques (14 Fälle) wurden mittels Semi-Dünnschnitten von Epon-eingebetteten Biopsien quantitativ analysiert. Als Kontrollen wurden Biopsien von Epikutan-Test-Reaktionen, Kontaktdermatitis, initialer Psoriasis und Erythema chronicum migrans untersucht. Eine hohe Prozentzahl von Lutzner-(Sézary)-Zellen fand sich ständig beim Sézary-Syndrom und gelegentlich bei der Parapsoriasis en plaques. Bei der Mycosis fungoides überwogen lymphocytoide Zellen mit helleren Kernen als bei normalen Lymphocyten. In den meisten Tumorläsionen sowohl bei der Mycosis fungoides als auch beim Sézary-Syndrom fand sich eine erhöhte Prozentzahl von Immunoblasten. Lymphocyten waren der häufigste Zelltyp bei der Parapsoriasis en plaques und bei den Kontrollen. Diese Befunde könnten nützlich für die Diagnostik von Problemfällen sein, für die die Semi-Dünnschnitt-Technik als eine weitere Methode empfohlen wird.
    Notes: Summary Semi-thin sections are superior to paraffin sections for differentiating lymphoid cells. To test their possible significance in the diagnosis of cutaneous T-cell lymphomas, the following investigation was made: A quantitative analysis of lymphoid cells in the cellular infiltrate of cutaneous lesions of mycosis fungoides (11 cases), Sézary's syndrome (9 cases), and parapsoriasis en plaques (14 cases) was made using semi-thin sections of eponembedded biopsies. As controls biopsies of patch test reactions, contact dermatitis, initial psoriasis, and erythema chronicum migrans were studied. A high percentage of Lutzner (Sézary) cells was consistently found in Sézary's syndrome and occasionally in parapsoriasis en plaques only. In mycosis fungoides lymphocytoid cells with the nuclei, less dense than in normal lymphocytes were predominant. In most tumorous lesions of mycosis fungoides and of Sézary's syndrome an increased percentage of immunoblasts was noted. Normal lymphocytes were the most frequent cell type in parapsoriasis en plaques as well as in the controls. These findings may prove helpful in the diagnosis of problem cases, for which the use of semi-thin sections is recommended.
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  • 111
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    Archives of dermatological research 265 (1979), S. 91-99 
    ISSN: 1432-069X
    Keywords: Electron microscopy ; Civatte body ; Atrophy ; Light sensitivity ; Heredity ; Elektronenmikroskopie ; Civatte-Körperchen ; Atrophie ; Lichtempfindlichkeit ; Vererbung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Zwei Patienten (insgesamt 4), zwei Brüder, mit »The diffuse and macular atrophic dermatosis» wurden beobachtet. Das familiäre Vorkommen, die «peau citréine»-Plaquen an der dorsalen Seite des Rumpfes, sowie eine kongenitale Phimose mit einer oberflächlichen Atrophie des Glans Penis, sind die neuen Befunde. Licht- und elektronenmikroskopische Befunde einer «peau citréine»-Plaque und einer erythematösen, skleroatrophischen Plaque werden geschildert. Es wurde auch gezeigt, daß die elastischen, färbungspositiven kugelähnlichen Strukturen, die in ungewöhnlich großer Zahl in der oberen Dermis gefunden wurden, fortgeschrittenere transformierte Civatte-Körperchen darstellen, die epidermale Zellen enthalten.
    Notes: Summary Two brothers with the “diffuse and macular atrophic dermatosis” making a total of 4 patients are reported. The familial occurrence, numerous large “peau citréine” plaques situated on the dorsum of the upper trunk and congenital phimosis with superficial atrophy of glans penis, represent the additional features reported. The light and electron microscopic findings of the least affected site on the arm, of a “peau citréine” and of an erythemoscleroatrophic plaque, none previously studied, have been reported. Among other items, it was also found that the elastic stain-positive globe-like structures found in an unusually large number throughout the edematous upper dermis represent more advancely transformed “Civatte bodies” containing epidermal filamentous cell material.
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  • 112
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    Annals of hematology 39 (1979), S. 177-190 
    ISSN: 1432-0584
    Keywords: Chronische myelo-monozytäre Leukämie ; Seeblaue Histiozyten ; Knochenmarksbiopsie ; Elektronenmikroskopie ; Chronic myelomonocytic leukemia ; Sea-blue histiocytes ; Bone marrow biopsy ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Clinical data and light and electron microscopic findings are presented in a patient with chronic myelomonocytic leukemia of about 5 years' duration and no need for specific therapy. Cytogenetic studies failed to demonstrate a Philadelphia-chromosome. The leading clinical symptoms were anemia, moderate hepatomegaly, and leukocytosis with monocytes in the peripheral blood count. Light microscopy of bone marrow cores showed hypercellularity of neutrophil granulocytic and monocytic cell lines including some precursor forms. Electron microscopy confirmed the existence of a biphasic myelomonocytic cell proliferation with predominance of mature forms in both lineages; there were no gross cellular abnormalities and no “hiatus leukaemicus”. Conspicuous were cells of an undeterminated origin apparently neither belonging to the neutrophil granulocytic nor monocytic series and large histiocytic cells, possibly corresponding to the so-called sea-blue histiocytes of light microscopy. The high degree of maturation of both cell lines in the bone marrow is in accordance with the relatively benign and prolongated course of this rare type of leukemia.
    Notes: Zusammenfassung Von einem Patienten mit einer chronischen myelo-monozytären Leukämie von etwa 5 Jahren Dauer und ohne spezifische Therapie werden klinische sowie licht- und elektronenmikroskopische Befunde vorgestellt. Zytogenetische Untersuchungen ließen ein Philadelphia-Chromosom nicht erkennen. Die führenden Symptome waren eine geringe Anämie, eine mäßige Lebervergrößerung und Leukozytose mit Monozyten im peripheren Blutausstrich. Lichtmikroskopische Untersuchungen des Knochenmarkes zeigten eine Zellvermehrung der neutrophilen granulozytären und der monozytären Zellreihen einschließlich einiger Frühformen. Die Elektronenmikroskopie bestätigte das Vorhandensein einer biphasischen myelo-monozytären Zellproliferation mit Vorwiegen der reifen Formen in beiden Zellinien. Es bestanden keine bemerkenswerten zellulären Anomalien und kein „hiatus leucaemicus“. Auffallend waren Zellen unbestimmbarer Herkunft, die weder der neutrophilgranulozytären oder monozytären Reihe sicher zuzuordnen waren, und große histiozytäre Zellen, die wahrscheinlich den sogenannten „seeblauen Histiozyten“ der Lichtmikroskopie entsprechen. Der hohe Grad der Ausreifung in beiden Zellinien im Knochenmark steht in Übereinstimmung mit dem relativ gutartigen und langen Verlauf dieses seltenen Types einer Leukämie.
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  • 113
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    Acta neuropathologica 45 (1979), S. 17-25 
    ISSN: 1432-0533
    Keywords: Brindled mutant mouse ; Male hemizygotes ; Neuronal degeneration ; Ultrastructure ; Giant mitochondria ; Copper deficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The brindled mouse (Mobr) is a neurological mutant mouse with clinical and biochemical features closely similar to Kinky hair syndrome (KHS) in humans. Neuronal degeneration in the cerebral cortex and thalamic nuclei was the constant neuropathological lesions in the CNS of the male hemizygotes of this mutant (Yajima and Suzuki, 1978). Ultrastructurally, many cortical neurons contained enlarged mitochondria with prominent tubular or vesicular cristae, which were similar to those described in the Purkinje cells in the human KHS (Ghatak et al., 1972) and in the rat brain with copper deficiency (Prohaska and Wells, 1975). Such mitochondria were observed not only in the degenerating neurons but even in the otherwise normal-appearing cortical neurons, suggesting that the mitochondrial damage possibly related to the deficient activities of the copper containing enzymes (cytochrome oxidase, etc.) preceded the neuronal degeneration. Many mitochondria in the severely degenerated neurons contained numerous electron dense spicules of possible calcium. Although rare, similar morphological alteration of neuronal mitochondria was also noted in the female heterozygotes, indicating the presence of possible subclinical defect in copper transport in the heterozygotes as well.
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  • 114
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    Acta neuropathologica 45 (1979), S. 187-194 
    ISSN: 1432-0533
    Keywords: Human adenovirus 12 ; Hamsters ; Subcutaneous neuroblastomatous tumor ; T-antigens ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Single subcutaneous inoculation of human adenovirus type 12 (Ad. 12), 0.05–0.1 ml of 108.0 TCID50 HEK cells/0.1 ml, was made on the back of 0-day-old hamsters. In 21 of 25 hamsters (84.0%), multiple solid tumors developed close to the inoculation site within 3 months. No control hamsters developed tumors. Tumor histopathology revealed the characteristic Homer Wright rosettes of neuroblastoma. Ad. 12-specific tumor antigens were demonstable in both the primary and the cultured tumor cells by the hnmunofluorescein technique. Histochemical demonstration of cholinesterase and NADH oxidoreductase gave rise to a predominantly positive intracytoplasmic granule within the tumor cells. Electron microscopy showed remarkably iniform cell morphology: small, undifferentiated neuroblastic cells with poorly developed intracytoplasmic organelles; many possessed characteristic solitary cilia in a 9+0 tubules pattern. Intercellular junctions were poorly developed. Search for an incipient tumor cell aggregate by means of immunofluorescein T-antigen detection was carried out through a 240-h period following Ad. 12 inoculation. A sequential study in parallel with electron microscopic examination of the normal subcutaneous tissue proved that neuroblastic cells closely associated with the muscle spindle anlage could preferentially become the most sensitive target for Ad. 12 tumorigenesis.
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  • 115
    ISSN: 1432-0533
    Keywords: Sensory neuropathy ; Nerve biopsy ; Electron microscopy ; Quantitative study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An electron microscope study and quantitation of myelinated and unmyelinated fibers of seven nerve biopsies performed in sporadic cases of idiopathic sensory neuropathy is reported. The number of myelinated fibers is markedly decreased or absent in every case. On the contrary, the unmyelinated fiber numbers are normal or increased. In most cases, the small diameter myelinated and unmyelinated fibers proportions are higher than those of control biopsies. The electron microscope study discloses evidence of degeneration of Wallerian type and regeneration is also indicated by quantitative studies. Regenerative phenomena seem more obvious in sporadic cases than in previously reported studies of familial cases.
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  • 116
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    Acta neuropathologica 47 (1979), S. 205-211 
    ISSN: 1432-0533
    Keywords: Brain tumor cells ; Chemical carcinogen ; Benzo(a)pyrene ; Oncogenesis ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ultrastructural study was performed on normal and Benzo(a)-pyrene (B(a)P)-transformed fetal mouse brain cells. Early subcultures of a strain initiated from whole brain presented three cell types in vitro: astroglial, poorly differentiated glial, and spongioblastic types. After B(a)P-treatment, there was an exclusive transformation and the growth of neuroglia sometimes without gliofibrillary maturation, but with the presence of glial fibrillary acidic protein (GFAP) in the cytoplasm. Early subcultures of another strain initiated from cortex only presented poorly differentiated neuroglial cells. After transformation, cell maturation as evidenced by gliofibrillogenesis and GFAP production by these cells was observed. In both cases, the potentiality of glial differentiation after in vitro malignant transformation by a chemical carcinogen seemed preserved.
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  • 117
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    Acta neuropathologica 45 (1979), S. 111-115 
    ISSN: 1432-0533
    Keywords: Brain tumor ; Rhabdomyosarcoma ; Mesenchymal cell ; Myotube ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of primary cerebral rhabdomyosarcoma in a 51-year-old female is reported. The histogenesis of this tumor is discussed. The clinicopathological features of 10 previously reported similar tumors of the CNS are briefly reviewed. Histologically the tumor was polymorphic, but composed of poorly differentiated cells interpreted as rhabdomyoblasts without definite cross-striation. Electron microscopy established that the poorly differentiated cells were of rhabdomyosarcomatous nature, compatible with presumptive myoblasts and analogous to developing fetal muscle.
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  • 118
    ISSN: 1432-0533
    Keywords: Muscular dystrophy ; Becker-type ; Benign X-linked ; Histopathology ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Muscle biopsies of two patients originally reported in the Göttingen family by Becker (1962) that formed the basis of separating a benign X-linked muscular dystrophy from the rapidly progressive Duchenne-type X-linked muscular dystrophy, revealed mild pathological changes in the younger patient and more advanced in the older one, consisting of increased spectra of fiber diameters, endomysial fibrosis, angulated fibers, pyknotic nuclear clumps and small groups of atrophic fibers. Essentially, both biopsies showed the same changes, but of different severity, possibly due to the differences in age and muscle biopsy sites. These changes were regarded “myopathic”, but a neurogenic component was suggested. Our observations accord well with those of a larger series (Bradley et al., 1978) where both electromyography and histopathology revealed a mixed “myopathic-neurogenic pattern” in patients with Becker-type dystrophy. Differential diagnostic aspects encompass Duchenne's muscular dystrophy, the other hereditary dystrophies and X-linked proximal spinal muscular atrophies. The precise nature of Becker-type muscular dystrophy requires morphological data on peripheral nerves, spinal roots and spinal cord anterior horn cells as well as sequential biopsy analysis to substantiate the primary site of pathology. However, on the basis of available data, it seems reasonable to suggest that the early changes of degeneration/regeneration which are accompanied by a markedly elevated CPK eventuate in the histopathologic and electromyographic patterns illustrated in these two patients with Beckertype dystrophy.
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  • 119
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    Acta neuropathologica 46 (1979), S. 239-241 
    ISSN: 1432-0533
    Keywords: Acromegaly ; Electron microscopy ; Growth hormone ; Pituitary adenoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Unusually large, oval and pleomorphic secretory granules were noted by electron microscopy in an acidophilic adenoma of the pituitary. The tumor, which was removed by surgery from a 42-year-old woman with elevated blood growth hormone levels and the clinical features of acromegaly, was found to contain growth hormone by the immunoperoxidase technique. This ultrastructural abnormality of secretory granules was not reported so far and was not seen among the 58 cases of growth hormone-producing adenomas investigated in our laboratory. The present case clearly shows that the cytogenesis and cellular composition of pituitary adenomas cannot be determined by solely examining the size and shape of secretory granules.
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  • 120
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    Acta neuropathologica 46 (1979), S. 11-15 
    ISSN: 1432-0533
    Keywords: Meningioma ; Cell culture ; Ultrastructure ; Cell junctions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ultrastructural alterations in human meningioma cells grown in vitro are reported. In early passages the cells retain some of the characteristic features of the original tumors. These include interdigitations associated with intercellular junctional devices (e.g., desmosomes, gap junctions). However, with repeated subculture these features tend to be less frequent. Typical whorl formations are observed only in primary cultures. The nunber of cytoplasmic filaments, lipid inclusions and other dense bodies increases with time in culture. Cytoplasmic invaginations into nuclei and the appearance of very large cells become more frequent in repeatedly transferred cultures.
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  • 121
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    Acta neuropathologica 47 (1979), S. 75-79 
    ISSN: 1432-0533
    Keywords: Neurotoxicity ; Cyanate ; Demyelination ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of sodium cyanate (NaNCO) on the nervous system of Maccaca nemestrina were studied at 2, 4, and 6 months of administration of the drug. The two groups injected with daily doses of 35 and 25 mg/kg/day of Na-cyanate developed a predominantly demyelinating lesion in the pyramidal tracts of the spinal cord. No neuronal changes were observed in the motor cortex, basal ganglia, midbrain, medulla or anterior horn cells of the spinal cord. There was no evidence of peripheral neuropathy. A comparison between the cyanate induced neuropathy in the rat and in the primate was drawn. Ultrastructurally, both species developed a demyelinating process of central or peripheral myelin characterized by vacuolation of the myelin sheath, removal of myelin debris by macrophages and re-myelination. There was little evidence of axoplasmic damage except for an occasional distended fiber containing abundant dense bodies and whorls of neurofilaments. Oligodendrocytes and Schwann cells were electron microscopically intact and participated actively in remyelination. Maccacas maintained at 15 mg/day and sham animals remained normal clinically and anatomically. The predominantly myelinotoxic effect of cyanate is similar to that produced by other myelinotoxic agents and is attributed to a selective modification of myelin proteins by carbamylation.
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  • 122
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    Acta neuropathologica 47 (1979), S. 189-196 
    ISSN: 1432-0533
    Keywords: Childhood dermatomyositis ; Muscle biopsy ; Electron microscopy ; Tubular arrays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Muscle biopsies from 12 patients with a typical clinical picture of dermatomyositis have been examined by electron microscopy. Endothelial cells of intramuscular blood vessels, their basal lamina, pericytes, muscle fibers, and satellite cells show degenerative or regenerative alterations. In nine patients, tubular arrays were noted in the cisterns of endoplasmic reticulum of endothelial cells, pericytes, lymphocytes, macrophages and satellite cells. Other types of inclusions were also observed. The pathogenesis of the disease is discussed.
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  • 123
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    Acta neuropathologica 47 (1979), S. 61-66 
    ISSN: 1432-0533
    Keywords: Experimental tumors ; Tissue culture ; Scanning ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Serially transplanted neurogenic tumors of experimental origin were explanted in vitro and analyzed by scanning electron microscopy. In explants of intracerebrally transplanted gliomas, small stellate cells with branching processes were observed; in transplanted tumors of the peripheral nervous system, slender bipolar cells as well as fibroblasts emerged. The stereoscopic features were compared with the picture of conventional light microscopy. The findings are consistent with the assumption of the glial derivation of CNS-tumors induced with neurotropic alkylating carcinogens. The peripheral tumors are composed of Schwann-cell like elements and fibroblasts. The significance of the results for the cytogenetic derivation of brain tumors are discussed.
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  • 124
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    Acta neuropathologica 45 (1979), S. 159-160 
    ISSN: 1432-0533
    Keywords: Tight junction ; Choroid plexus papilloma ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Four cases of choroid plexus papilloma (CPP) obtained at the time of surgical excision were examined by electron microscopy and compared with normal choroid plexus (CP) of mouse and chick. In apical tight junctions fusion of the two outer leaflets of the adjacent cytoplasmic membrane was verified as in CP. This fact suggests that there is a blood-CSF barrier not only in CP but also in CPP.
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  • 125
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    Acta neuropathologica 46 (1979), S. 139-144 
    ISSN: 1432-0533
    Keywords: Perineurium ; Peripheral ganglion ; Diffusion barrier ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The perineurial diffusion barrier to horseradish peroxidase (HRP) and ferritin was investigated in superior cervical ganglia of rats and mice. The ganglion was surrounded by a delicate epineurium and 2–5 perineurial lamellae joined by zonulae occludentes and desmosomes. Following local application of tracers the animals were killed after 5, 30, and 60 min and the distribution of HRP and ferritin was studied by light and electron microscopy. The inner layers of the ganglionic perineurium prevented diffusion of both HRP and ferritin into the endoneurium. Owing to the fewness of the perineurial lamellae investing the ganglion. HRP had often extended to the innermost lamella 60 min after application. HRP and ferritin were present in vesicles of ganglionic perineurial cells. There was no passage of tracers via intercellular junctions.
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  • 126
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    Acta neuropathologica 46 (1979), S. 163-166 
    ISSN: 1432-0533
    Keywords: Electron microscopy ; Pituitary adenoma ; Annulate lamellae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electron microscopy revealed the presence of annulate lamellae in the cytoplasm of a heavily granulated prolactin cell adenoma that had been removed from a 34-year-old male patient presenting impotence. To our knowledge this is the third case of pituitary adenomas where annulate lamellae are reported.
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  • 127
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    Acta neuropathologica 47 (1979), S. 55-59 
    ISSN: 1432-0533
    Keywords: Virus-like particle ; Nucleic acid ; Muscle ; Cytochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Picornavirus-like crystalline arrays were found in the skeletal muscle of a victim of a traffic accident. Individual particles measured approximately 22 nm in diameter and were arrayed in a hexagonal or triangular pattern. Cis-platinum (II) staining of these virus-like particles showed that these particles were not glycogen but contained nucleic acids, and the staining according to Bernhard also showed these particles contained RNA. Through the combination of the methods of Heinen (1977) and Bernahrd (1969), we can confirm that virus-like crystalline structures found electron microscopically contain nucleic acids and possibly represent virions.
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  • 128
    ISSN: 1432-0533
    Keywords: Visna ; Slow viral infection ; CSF ; Ultrastructure ; Myelin fractions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An electron microscopic examination was done on 8 samples of cerebrospinal fluid (CSF) from Icelandic sheep infected by the intracerebral route with visna virus. The specimens were collected 1 month, 2 months, and 4 years after infection. A differential cell count done on low-power electron micrographs showed that the cellular exudate was composed of mononuclear cells mainly macrophages and lymphocytes with a few plasma cells. Macrophages were with one exception more numerous than lymphocytes and an increased proportion of macrophages showed evidence of phagocytosis with time after infection. Reactive lymphocytes were in general more numerous than small lymphocytes. Various stages in the maturation of plasma cells were observed. The cellular composition in the CSF is compatible with the view that visna is an immunopathological process. Myelin figures and fragments of myelinated axons were observed in two specimens indicating an active myelin-breakdown. The possibility that escape of myelin into the CSF may lead to sensitization to myelin antigens and perpetuation of this chronic neurologic affection is discussed. Visna virions could not be demonstrated.
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  • 129
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    Acta neuropathologica 48 (1979), S. 63-66 
    ISSN: 1432-0533
    Keywords: Acute multiple sclerosis ; Virus-like particles ; Demyetination ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Novel, superficially ‘virus-like’ hollow-cored particles 50–60 nm in diameter were found in the perivascular extracellular space of the brain from a patient who died with acute multiple sclerosis (MS). It is concluded that they are not virions but are derived from myelin undergoing vesicular demyelination. This case demonstrates the need for caution in the interpretation of unusual electron microscopic appearances.
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  • 130
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    Acta neuropathologica 45 (1979), S. 241-245 
    ISSN: 1432-0533
    Keywords: Myelin formation ; Ganglioglioma ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Formation of myelin sheaths by neoplastic cells was found in a spinal ganglioneuroma. All phases of initial myelination were observed including the formation of a mesaxonal spiral and the fusion of its famellae into a major dense line. A unique aspect of neoplastic myelin formation was the formation of sheaths around bundles of extracellular fibrils rather than axons or cell processes. Formation of myelin sheaths around extracellular material has never been observed before. The findings have implications on the mechanisms controlling initial myelination.
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  • 131
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    Acta neuropathologica 45 (1979), S. 147-152 
    ISSN: 1432-0533
    Keywords: Progressive supranuclear palsy ; Neurofibrillary tangles ; Electron microscopy ; Straight filaments ; Twisted tubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of subcortical neurofibrillary tangles was investigated in pallidum, substantia nigra, periaqueductal gray, pontine reticular gray, and dentate nucleus of 5 autopsy cases of Progressive Supranuclear Palsy. Only tangles due to straight 150 Å wide filaments have been detected. These findings, obtained from a large series of cases and areas examined, confirm previous observations on the fine structure of neurofibrillary tangles in Progressive Supranuclear Palsy and suggest that the association between tangles due to straight filaments and tangles due to twisted tubules, so far described in one case, is probably exceptional.
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  • 132
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    Acta neuropathologica 46 (1979), S. 235-237 
    ISSN: 1432-0533
    Keywords: Paraganglioma ; Cauda equina region ; Neurosecretory granules ; Nerve fibers ; Endothelial cells ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Some new ultrastructural observations are documented in a paraganglioma in the cauda equina region. These include the presence of nerve fibers in the tumor capsule, clear vesicles and tubulo-vesicular structures in some cytoplasmic processes in the tumor, fenestrated endothelial cells, and numerous tubular bodies in some endothelial cells.
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  • 133
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    Acta neuropathologica 47 (1979), S. 163-165 
    ISSN: 1432-0533
    Keywords: Dysplastic gangliocytoma ; Cerebellum ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of a dysplastic gangliocytoma of the cerebellum is studied by means of the Golgi method and electron microscopic examination. Thick proximally unbranched dendrites with terminal arborizations and varicose influorescences in the form of a basket are stained with the Golgi method. Axons are always descendant to the inner myelinated layer of the redistributed cerebellar cortex, while ascendant collaterals are observed at the level of the outer myelinated layer. Clear and dense-core vesicles and synapses are common in the cellular profiles under electron microscopic examination. From these data and because of the lack of putative connections through the white matter, an organized, self-regulated, catecholamine-mediated complex may be postulated.
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  • 134
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    Development genes and evolution 186 (1979), S. 65-70 
    ISSN: 1432-041X
    Keywords: Sea urchin ; Embryo ; Collagen ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Collagen fibrils with a main period banding of 610 Å and 220 Å in width were observed in the blastocoel of 72-h embryos of the sea urchin,Strongylocentrotus purpuratus. Non-striated fibrils of 50 Å diameter were also observed. The collagen is seen in highest concentration in the vicinity of mesenchyme cells which are richly endowed with endoplasmic reticulum and secretory vesicles. A role for collagen in cell attachment, orientation and spicule formation is discussed.
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  • 135
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    Development genes and evolution 185 (1979), S. 333-346 
    ISSN: 1432-041X
    Keywords: Chick embryo ; Limb bud ; Ultrastructure ; Cell death
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The ultrastructural changes in the wing bud afterapical ectodermal ridge (A.E.R.) removal was studied to re-examine the issue of distal mesenchymal cell death. The A.E.R. of the right wing bud was removed microsurgically from chick embryos of stages 18 to 22 (HH 1951). The wing buds were examined at three hour intervals up to twelve hours after the operation with light, transmission and scanning electron microscopy. The main findings were: (1) Immediate and temporary shrinkage of the mesenchymal extracellular space 100 to 150 μm and chromatin condensation in the cells 50 to 75 μm from the wound. (2) Death of ectodermal and mesenchymal cells in the immediate vicinity of the wound. (3) Formation of a single squamous-like layer of mesenchymal cells to cover the wound. (4) Occasional evidence of cell death in the distal mesenchyme at later times after the operation. The pattern of cell death observed suggests only a traumatic etiology, and gives little evidence for the postulated developmental significance of cell death following A.E.R. removal.
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  • 136
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    Calcified tissue international 29 (1979), S. 101-105 
    ISSN: 1432-0827
    Keywords: Osteon ; X-ray diffraction ; Pole figures ; Electron microscopy ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The X-ray diffraction method based on pole figures has been applied to single osteon samples in order to obtain information about the texture of the inorganic bone fraction and the way it changes during calcification. The osteon samples were cylindrically shaped, with axes corresponding to those of the haversian canals. Selection was carried out according to the degree of calcification and the orientation of collagen bundles and inorganic particles. Osteons at both the initial and final stages of calcification were chosen. Arrangements of fiber bundles and inorganic particles in successive lamellae characteristic of three types of osteons were selected: longitudinal, alternate, and transversal. The results indicate that in all three types of osteons, the long axis of the sample is apparently the only direction of orientation because the transversally oriented crystallites give an isotropic diffuse scattering as would be expected if all the inorganic particles were irregularly oriented around the osteon axis. The number of longitudinally oriented crystallites increases progressively from transversally oriented osteons to alternately and longitudinally oriented ones. The crystallite orientation in an axial direction increases in fully calcified osteons. This last result is in agreement with the electron microscopic finding that the long needle-shaped crystallites covering much more than a major collagen period and measuring 40–45 Å in width increase in number as calcification proceeds.
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  • 137
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    International archives of occupational and environmental health 44 (1979), S. 25-43 
    ISSN: 1432-1246
    Keywords: Electron microscopy ; Morphometry ; Freeze etching ; Liver ; Aging ; Polychlorinated biphenyls ; Elektronenmikroskopie ; Morphometrie ; Gefrierätzung ; Leber ; Altern ; polychlorierte Biphenyle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In der vorliegenden Untersuchung wurden jungen und alten männlichen Wistarratten polychlorierte Biphenyle (PCB) i.p. appliziert. Die altersbedingten und die hepatotoxischen Veränderungen in der Leber wurden licht- und elektronenmikroskopisch erfaßt. Des weiteren wurden Membranveränderungen mit der Gefrierätzung nachgewiesen. Neben den altersbedingten Veränderungen im Vergleich der beiden Kontrollkollektive fällt vor allem die exzessive Proliferation des glatten endoplasmatischen Retikulums auf, welche nach PCB-Applikation in den Hepatocyten nachzuweisen ist. Bei den jungen Ratten betrug die Vermehrung der Oberflächen-dichte dieser Membranen im Vergleich zu den Kontrolltieren 803% (P〈0,001) und bei den alten Ratten 282% (P〈0,001). Bei alten anderen untersuchten Parametern wurden sowohl bei den jungen als auch bei den alten Ratten statistisch signifikante Verringerungen nach PCB-Gabe festgestellt.
    Notes: Summary Thin-section and freeze-fracture techniques have been employed to investigate the ultrastructure of PCB-intoxicated rat liver of different ages. Besides alterations in the supramolecular structure of the plasma membranes, excessive proliferation of smooth endoplasmic reticulum (SER) in the hepatocytes was observed. In young rats, the surface density increased by up to 803% (P〈0.001) and in old rats up to 282% (P〈0.001) compared with the control rats. All other investigated parameters decreased significantly after the application of PCB.
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  • 138
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    Pflügers Archiv 381 (1979), S. 127-135 
    ISSN: 1432-2013
    Keywords: Na+−K+-ATPase ; Rat kidney ; Electron microscopy ; Substructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purified membrane-bound Na+−K+-ATPase from rat kidney outer medulla was studied by freeze-fracturing, by freeze-etching and by negative staining. Freeze-fracturing of purified Na+−K+-ATPase membranes shows intramembraneous particles with a diameter of about 100 Å. The frequency of these intramembraneous particles — as estimated from the particle densities on the two fracture faces — lies between 4700 and 5600 particles per μm2. Applying rotary shadowing a four partite substructure could be detected in these intramembraneous particles observed on the fracture planes. The same four partite substructure was detected in particles observed on freeze-fractured and rotary shadowed intact baso-lateral plasma membranes of the thick ascending limb of Henle's loop. Particles could be also detected on both membrane surfaces of the purified Na+−K+-ATPase. These surface particles have about the same diameter and are present at about the same frequency as those observed within the freeze-fractured membranes. Negative staining of isolated Na+−K+-ATPase membranes showed particles on both membrane surfaces with a diameter between 30 and 50 Å, at a frequency of about 19,000 per μm2. On aspects of membrane edges we observed structures which suggest a transmembraneous connection of the negatively stained particles on both membrane surfaces. Our results suggest that the Na+−K+-ATPase protein is composed of four units and that each unit spans the cell membrane. The native enzyme structure of the Na+−K+-ATPase protein seems to be preserved during freeze-fracturing and freeze-etching. It is proposed that the four enzyme units of the Na+−K+-ATPase complex are dissociated during the negative staining procedure.
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    Journal of molecular medicine 57 (1979), S. 451-456 
    ISSN: 1432-1440
    Keywords: Menschliches Plasma ; DNS ; Elektronenmikroskopie ; Konzentration ; Human plasma ; DNA ; Electron microscopy ; Concentration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The DNA content in plasma of five healthy human individuals has been estimated. Structures ascertained by electron microscopy have been identified as double-stranded DNA. Depending on the isolation procedure applied the DNA molecules found may originate from free and/or complexed forms of DNA. The lengths range from less than 0.2 µm up to about 13 µm. DNA concentration is in the range of 3 to 11 ng/ml.
    Notes: Zusammenfassung Es wurde der DNS-Gehalt im Plasma fünf gesunder Testpersonen ermittelt. Elektronenmikroskopisch darstellbare Strukturen konnten als doppelsträngige DNS charakterisiert werden. Bedingt durch die Isolierungsmethode resultiert die gefundene DNS sowohl von freier und/oder DNS, die in komplexierter Form im Plasma vorliegt. Die Moleküllängen variieren von weniger als 0,2 µm bis zu ca. 13 µm. Die Konzentration liegt im Bereich von 3–11 ng DNS/ml.
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  • 140
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    Journal of cancer research and clinical oncology 95 (1979), S. 197-207 
    ISSN: 1432-1335
    Keywords: Telangiectatic osteosarcoma ; Histogenesis ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Recent investigations have shown that telangiectatic osteosarcoma has a poorer prognosis than other osteosarcomas. To elucidate the histogenesis of TOS two cases were investigated on the electron microscopic level. The results show that besides anaplastic, osteoblast-like, and fibroblast-like tumor cells angiosarcomatous components can be observed in this malignant bone tumor, which are characterized by endothelial cells with pinocytotic vesicles, tight intercellular junctions, fine fibrils, and so-called Weibel-Palade bodies in their cytoplasm. From these results, it is concluded that telangiectatic osteosarcoma is derived from multipotent mesenchymal cells with potential differentiation into various directions, such as osteoblast-like cells, endothelial cells, and fibroblast-like cells.
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  • 141
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    Journal of molecular medicine 57 (1979), S. 641-646 
    ISSN: 1432-1440
    Keywords: Mitochondria ; Membranes ; Cytochrome oxidase ; Fluorescence methods ; Electron microscopy ; Mitochondrien ; Membranen ; Cytochromoxidase ; Fluoreszenzmethoden ; Elektronenmikroskopie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Biologische Membranen sind im wesentlichen asymmetrische zwei-dimensionale Lösungen von Proteinen in einer bimolekularen Lipidschicht. Das allgemeine Aufbauprinzip und viele physikalische Eigenschaften biologischer Membranen lassen sich dadurch erklären, daß sowohl die Membranproteine als auch die Membranlipide hydrophile und hydrophobe Stellen besitzen. Die meisten biologischen Eigenschaften einer Membran werden durch die Membranproteine bestimmt, die richtungsgebundene Prozesse katalysieren können. Anhand des Membranproteins Cytochromoxidase wird gezeigt, wie die räumliche Anordnung von Membranproteinen durch chemische, fluorometrische und elektronenoptische Methoden studiert werden kann. In den meisten Fällen ist es allerdings heute noch nicht möglich, die Funktionen einer Membran aufgrund ihres molekularen Bauprinzips zu erklären.
    Notes: Summary Biological membranes are essentially asymmetric two-dimensional solutions of proteins in a bimolecular lipid layer. The overall structure and many physical properties of biological membranes can be explained by the fact that membrane proteins and membrane lipids contain hydrophilic as well as hydrophobic domains. Most biological properties of the membrane are determined by the membrane proteins which can catalyze directional processes. With the membrane protein cytochrome oxidase it will be demonstrated how the three-dimensional arrangement of membrane proteins can be studied by chemical, fluorometric, and electron optical methods. However, it is in most cases still impossible to explain the function of a membrane on the basis of its molecular architecture.
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  • 142
    ISSN: 1432-072X
    Keywords: Acetobacter suboxydans ; Bacteriophage A-1 ; Restriction ; Modification ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A bacteriophage ofAcetobacter suboxydans was isolated and found to correspond to type A phage according to Bradley's classification. The phage contains double stranded DNA. The length of the latency period and burst size could not be precisely determined because of apparent non-synchronous release of phage from single infective cycles. The host range was determined using 24 strains ofAcetobacter andGluconobacter species. Evidence for a probable occurence of host determined restriction and modification was obtained withAcetobacter suboxydans strain ATCC 621. The phage is designated A-1 and it is the first one to be reported forAcetobacter.
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    Archives of microbiology 123 (1979), S. 101-103 
    ISSN: 1432-072X
    Keywords: Bdellovibrio ; Cyanobacteria ; Marine sponges ; Symbiosis ; Infection ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A bdellovibrio-like bacterium was observed infecting unicellular symbiotic cyanobacteria in two coral reef sponges, Neofibularia irata and Jaspis stellifera. The infecting bacterium, which was located between the cell wall and the cytoplasmic membrane of the cyanobacteria, was similar in size and appearance to previously described bdellovibrios. This observation is believed to extend the host range of the bdellovibrios.
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  • 144
    ISSN: 1432-072X
    Keywords: Methanogenium cariaci ; Methanogenium marisnigri ; Marine methanogenic bacteria ; Ultrastructure ; TaxonomyMethanogenium gen. nov.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A new genus of marine methanogenic bacteria and two species within this genus are described.Methanogenium is the proposed genus andMethanogenium cariaci the type species. Cells of the type species are Gram-negative, peritrichously flagellated, irregular cocci with a periodic wall surface pattern. Colonies formed by these bacteria are yellow, circular and umbonate with entire edges. The DNA base composition is 52 mol% guanine plus cytosine. Formate or hydrogen and carbon dioxide serve as substrates for growth. Cells ofMethanogenium marisnigri are of similar shape but smaller diameter thanM. cariaci. The colonies ofM. marisnigri are convex, and the DNA base composition is 61 mol % G+C. Formate or hydrogen and carbon dioxide are growth substrates. Sodium chloride is required for growth of both methanogens.
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  • 145
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    Archives of microbiology 121 (1979), S. 53-59 
    ISSN: 1432-072X
    Keywords: Saccharomyces ; Kluyveromyces ; Ultrastructure ; Ascospore wall ; Taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Three types of structure of the ascospore wall were found among the haploid Saccharomyces species examined: a warty wall (S. rouxii), a smooth wall with a single electron-light inner layer (S. bailii) and a smooth wall with a double light inner layer (S. montanus, S. florentinus). The latter type also occurred in Kluyveromyces thermotolerans and K. waltii. In K. fragilis spores the wall had a single light inner layer. The taxonomic implications of these findings were discussed.
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  • 146
    ISSN: 1432-072X
    Keywords: Alcohol dehydrogenase ; Acetaldehyde dehydrogenase ; Clostridium kluyveri ; Electron microscopy ; Polygonal bodies ; Enzyme complex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The alcohol-acetaldehyde dehydrogenase complex of Clostridium kluyveri has been separated from contaminating β-hydroxybutyryl-CoA dehydrogenase by repeated precipitation with manganese and ammonium sulfate. Mn++ was required for maximum alcohol dehydrogenase activity. The molecular weight of the enzyme complex was 194,000 as determined by sucrose density gradient centrifugation. The enzyme complex has been shown to contain two types of subunits with molecular weights of 55,000±2,600 and 42,000±1,200, respectively which are arranged in “H”-shaped particles. In solutions with an ionic strength above 25 mM the enzyme complex precipitated in the form of lumps as has been shown with specific ferritin-conjugated antibodies. These lumps are assumed to be aggregated polygonal bodies present in C. kluyveri.
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  • 147
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    Archives of microbiology 121 (1979), S. 9-15 
    ISSN: 1432-072X
    Keywords: R-Bodies ; Kappa particles ; Free-living hydrogen bacteria ; Induction ; Electron microscopy ; Chemical composition ; Defective prophages ; Plasmids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract R-Bodies have been found in a recently isolated pseudomonas-like free-living hydrogen oxidizing bacterium. Their isolation, fine structure and chemical composition are described and compared with the R-bodies from the kappa particles (Caedobacter), obligate endosymbionts of Paramecium aurelia. The 2K 1 R-bodies exhibited essential characteristics of the kappa R-bodies; however, their size and some other structural aspects proved that they represent a new type of R-bodies. The presence of phage tail-like particles in cells induced with Mitomycin C is in favour of the hypothesis that the R-bodies might be coded by defective prophages, or by extrachromosomal elements.
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  • 148
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    Archives of microbiology 122 (1979), S. 17-27 
    ISSN: 1432-072X
    Keywords: Gliding bacteria ; CO2-requiring ; Periodontal disease ; Gram-negative ; Ultrastructure ; Capnocytophaga
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Gram-negative, anaerobic gliding bacteria were isolated from normal supragingival plaque and from periodontal lesions. Isolates could be divided into two size classes: small 2.4–4.2 μm×0.38–0.5 μm and large 4.8–5.8 μm×0.42–0.6 μm cells. The outer membrane was either loose-fitting and wavy, or taut, and of variable thickness. An electron-dense fuzz was discernible on several of the isolates. The periplasmic region was of variable electron-density. The genus Capnocytophaga has been proposed for these organisms based on morphological and cultural characteristics.
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  • 149
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    Archives of microbiology 123 (1979), S. 173-181 
    ISSN: 1432-072X
    Keywords: Bacillus subtilis ; Cell cycle ; DNA replication ; Cell division ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Bacillus subtilis strain Marburg was grown exponentially with a doubling time of 65 min. To follow the time course of various cell cycle events, cells were collected by agar filtration and were then classified according to length. The DNA replication cycle was determined by a quantitative analysis of radioautograms of tritiated thymidine pulse labeled cells. The DNA replication period was found to be 45 min. This period is preceded and followed by periods without DNA synthesis of about 10 min. The morphology and segregation of nucleoplasmic bodies was studied in thin sections. B. subtilis contains two sets of genomes. DNA replication and DNA segregation seem to go hand in hand and DNA segregation is completed shortly after termination of DNA replication. Cell division and cell separation were investigated in whole mount preparations (agar filtration) and in thin sections. Cell division starts about 20 min after cell birth; cell separation starts at about 45 min and before completion of the septum.
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  • 150
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    Journal of cancer research and clinical oncology 95 (1979), S. 225-232 
    ISSN: 1432-1335
    Keywords: Cultured tumour cells ; Ultrastructure ; 3-D Colonies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cultured hepatocellular carcinoma cells were studied during anchorage-independent growth in semi solid medium (Methocel). The regular occurrence of mitotic figures both at the surface and within the colonies precludes the possibility of such colonies being formed by re-aggregation. The estimated population doubling time in the three-dimensional (3-D) colonies is consistent with those two-dimensional of (2-D) colonies. Structures resembling bile canaliculi were observed between the closely opposed membranes from the well packed adjacent cells. Cell surface and ultrastructural features of the colonies and individual cells are presented and comparisons made with 2-D growth of normal and malignant liver cells in vitro. The formation of 3-D colonies may not only be an assay for transformed cells but also for predicting the type of tumors produced by re-innoculation of the in vitro transformed cells.
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  • 151
    ISSN: 1432-2307
    Keywords: Cloacogenic carcinomas ; Ano-rectal region ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The clinical and pathological features of four transitional cloacogenic carcinomas (TCC) are presented with particular reference to electron microscopy. The incidence of this tumour is 1.4% of all ano-rectal neoplasms. Three cases showed a gross appearance similar to the common rectal neoplasms. One tumour presented without an intraluminal lesion, but infiltrated the bowel wall and the anal glands. TCC show a distinct histological pattern. The degree of differentiation of the basic transitional cell component determines the “grading” of the lesion. We distinguish between grade I, II and III. Grade I lesions show uniform polygonal cells with only occasional mitotic figures. There is distinct palisading of the nuclei of the peripheral tumour cell layers. Grade II lesions are characterized by partial or total loss of the peripheral palisading. Grade III lesions are extremely anaplastic (“oat cell” carcinoma). This histological classification correlates well with the prognosis. Electron microscopic investigation of TCC revealed the ultrastructural features of basal cells. The uniform tumour cells with large nuclei contain tonofibrils, desmosomes and hemi-desmosomes, free ribosomes, and relatively few other organelles. We did not find keratinocytes or keratohyalin granules in these four cases of TCC. It is emphasized that TCC of the ano-rectal region differ fundamentally from the basalcell carcinomas of the skin in their biological behaviour.
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  • 152
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    Virchows Archiv 381 (1979), S. 313-329 
    ISSN: 1432-2307
    Keywords: Bronchial carcinoids ; Different types ; Cells of origin ; Ultrastructure ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Seven of eleven bronchial carcinoids investigated showed cells with small granules resembling P cells which have already been described in human fetal and adult lung; two of these P cell tumours showed distinctive paraganglioid features. One tumour showed peculiar ultrastructural findings resembling closely those previously reported by Black (1969) in a so called “pulmonary oncocytoma”. Three remaining cases showed large secretory granules resembling those of type 3 cells already described by Hage (1973 b) in bronchial carcinoids; one of these tumours produced large amounts of 5-hydroxytryptamine (5HT). It is concluded that, on cytological grounds, at least two types of tumours can be distinguished among bronchial carcinoids, i.e. P cell and type 3 cell tumours. Moreover, two varieties of P cell carcinoids have been recognized, showing either the less frequent and more distinctive paraganglioid structure or the more common trabecular structure.
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  • 153
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    Virchows Archiv 381 (1979), S. 159-178 
    ISSN: 1432-2307
    Keywords: Giant cell tumor ; Ultrastructure ; Acid phosphatase ; Lysosomes ; Bone tumors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Eleven benign giant cell tumors of bone were studied in the electron microscope, and the fine structural localization of acid phosphatase was elucidated. Three distinct cell types are always present in these tumors: stromal cells type 1; stromal cells type 2; and multinucleated giant cells. Small mononuclear cells may also occur, but are not likely to be actively participating in the neoplastic process. The range of variability in the fine structure of the different cell types constituting this tumor has been established. Variations in appearances include: a) presence of nuclear pseudoinclusions in stromal cells type 1 and multinucleated giant cells; b) aberrations in the structure of the rough surfaced endoplasmic reticulum in the same cell types; c) occurrence of ruffled borders, ectoplasmic layers and cytoplasmic labyrinths containing acid phosphatase in the giant cells. Some giant cells show evidence of marked phagocytic activity and contain large and numerous residual bodies carrying acid phosphatase. The significance of the interrelations between the different cell types are discussed and the possible role of stromal cells type 2 in immunological mechanisms directed against the tumor cells are mentioned.
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  • 154
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    Virchows Archiv 385 (1979), S. 77-91 
    ISSN: 1432-2307
    Keywords: Ultrastructure ; Ovary ; Clear cell carcinoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of an ovarian clear cell carcinoma in a 65 year old woman was analysed. The tumor cells were of both clear and “hobnail” types. Both were characterized by the presence of short microvilli, abundant glycogen granules, a well-developed granular endoplasmic reticulum and Golgi apparatus, scanty lysosomes and very few lipid bodies. The tubules and gland-like spaces were always separated from the stroma by a basement membrane. At ultrastructural level the tumor cells do not resemble at all those of clear cell renal carcinomas. On the other hand, their submicroscopic features are strongly similar to those of the clear cell tumors found elsewhere in the female genital tract, emphasizing therewith their very probable müllerian origin. It is recommended to eliminate the term “mesonephroma ovarii” to designate the clear cell carcinomas of the ovary.
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  • 155
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    Cell & tissue research 200 (1979), S. 15-27 
    ISSN: 1432-0878
    Keywords: Lymph vessels ; Testis ; Man ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of lymph vessels in the human testis was investigated using ink injection methods, and light and electron microscopy. Lymph capillaries occur in the septula testis but are absent in the intertubular tissue. They consist of endothelial cells provided with an incomplete basal lamina and anchoring filaments of the adjacent connective tissue. Frequently, the endothelial cells are separated by gaps measuring up to 2μm. The lymph capillaries of the septula testis are connected to lymph vessels in the rete testis and tunica albuginea. These vessels have occasional smooth muscle cells and valves. At the posterior margin of the testis, the network of lymph vessels merges into collecting ducts, which together with vessels derived from the rete testis are drained by the lymphatic system in the spermatic cord.
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  • 156
    ISSN: 1432-0878
    Keywords: Thyroid follicular cells ; Basal lamina, biosynthesis ; Cellular interaction ; Cell culture ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Porcine thyroid cells were cultured alone or in mixed cultures with mesenchymal cells. The formation of a basal lamina in vitro was investigated ultrastructurally. Follicular reassociation of thyroid cells occurred in both types of culture; however, it was followed by formation of the basal lamina only when mesenchymal cells were present. The present findings suggest an epithelial origin of the basal lamina resulting from an interaction with mesenchymal cells.
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  • 157
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    Cell & tissue research 200 (1979), S. 257-271 
    ISSN: 1432-0878
    Keywords: Anococcygeus muscle ; Innervation ; P-type nerves ; Purinergic nerves ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation of the rat anococcygeus muscle has been investigated ultrastructurally following fixation with a modified chromaffin reaction for the demonstration of biogenic amines (Tranzer and Richards, 1976). Three types of nerve profiles were revealed: (1) 60–70 % of the profiles are adrenergic; (2) less than 5% of the profiles appear to be cholinergic; (3) up to 40% of the profiles are distinguished by the presence of a characteristically high proportion of electron-opaque, chromaffin-negative vesicles, 85–110nm in diameter. This third type of profile was not affected by 6-OHDA, and is considered to represent the non-adrenergic, non-cholinergic inhibitory innervation of this tissue. Because of the morphological similarity of this nerve type, apart from the smaller vesicle size, to classical peptidergic nerve endings, they have been termed “small p-type” (sp-type). These results are discussed in relation to a previous report describing only two types of nerve profiles in this tissue (Gillespie and Lüllmann-Rauch, 1974).
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  • 158
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    Cell & tissue research 200 (1979), S. 299-309 
    ISSN: 1432-0878
    Keywords: Germ-free mice ; Inflammation ; Macrophages ; Peritoneum ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Peritoneal macrophage ultrastructure was analysed stereologically in germ-free mice given a single intraperitoneal injection of sterile, pyrogen-free saline. Thus the stimulant was non-particulate, non-antigenic and inorganic, and effects of immune reactions were minimal. Macrophages were recovered 1, 6, 24 and 72 h after stimulation. A sequence of structural alterations is reported which may be fundamental to macrophage activation. The plasma membrane and nuclear envelope increased in area within only 1 h of saline injection. During the next 5 h loss of plasma membrane, probably by pinocytosis, caused cellular “rounding” and clear-cut alteration in surface configuration. At the same time lysosome-like granules enlarged but decreased in number. By 24 h most cellular structures and compartments (including the plasma membrane) were enlarged. Morphological evidence of nuclear activation accompanied a rather modest enlargement of the nucleus at this stage. The RER hypertrophied last and must, therefore, be judged sufficient in resident macrophages to support the initial growth response which results after stimulation. Thus hypertrophy was observed eventually in every structure examined. Even the minimally activated macrophages resident in the peritoneum of germ-free mice respond readily to stimulation.
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  • 159
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    Cell & tissue research 200 (1979), S. 329-334 
    ISSN: 1432-0878
    Keywords: Median eminence ; Axon terminals ; Tanycytes ; Electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The present ultrastructural study proves the existence of nerve terminals closely apposed to the plasmalemmata of tanycytes in the rat median eminence. Several of these “axo-tanycytic” endings display remarkable accumulations of agranular endoplasmic reticulum in the form of pleomorphic vesicles which are closely apposed on either side of the plasma membrane of each cell compartment. Some of these vesicular profiles give the impression of structural continuity across both membrane systems. This phenomenon is discussed in the context of being a potential substratum for communication between both cell compartments.
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  • 160
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    Cell & tissue research 200 (1979), S. 291-298 
    ISSN: 1432-0878
    Keywords: Excitatory synapse ; Lateral line-canal organ ; Synaptic body ; Ultrastructure ; Lota lota (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the afferent synapse in hair cells of the lateral line-canal organ was studied using different fixation and staining techniques. Glutaraldehyde-fixed tissue without post-osmication, contrasted by section staining with uranyl acetate and lead citrate, was compared with (a) osmium tetroxide-fixed tissue followed by the same staining procedure, and with (b) glutaraldehyde-fixed tissue, block-impregnated with phosphotungstic acid (PTA). The results reveal a pronounced heterogeneity in the composition of the synaptic body, reflecting regional differences in chemical affinity to the fixatives and staining agents. It is proposed that the “intracleft substance”, the synaptic structure defined by the PTA staining technique, is actually due to the glutaraldehyde fixation procedure and is apparently the outer leaflet of the postsynaptic membrane. A special technique that allows alternate sections of a series to be differentially stained for electron microscopy is proposed.
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  • 161
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    Cell & tissue research 200 (1979), S. 337-344 
    ISSN: 1432-0878
    Keywords: Glomerulo-tubular feedback ; Tight junctions ; Macula densa ; Distal tubule ; Electron microscopy ; Freeze fracture ; Horseradish peroxidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the present study the tight junctions at the macula densa were compared to those of the adjacent straight and convoluted segments of the distal tubule using freeze fracturing and thin sectioning techniques. Only insignificant differences were found in the number of strands and the apico-basal depth of the tight junctions in the three distal tubular segments of rat, dog and tree shrew. In experiments with horseradish peroxidase on mice and tree shrews, the tracer did not penetrate the apical junctions in any of the distal tubular segments. Our findings do not support the concept of considerably higher permeability of the tight junctions at the macula densa, as previously reported. Gap junctions were never observed in the distal nephron. The present results suggest that the glomerulo-tubular feedback is more likely to be mediated by transcellular resorption of solutes than by passive diffusion through a leaky paracellular shunt pathway.
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  • 162
    ISSN: 1432-0878
    Keywords: T-lymphocytes ; Blast cells ; Lymph node ; Electron microscopy ; Stereology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Changes in the volumes and surfaces of subcellular compartments of unstimulated small lymphocytes and immunoblasts in mouse axillary lymph nodes have been established using stereological techniques. Blast transformation was induced in vivo with dinitrochlorobenzene (DNCB). Cell samples were obtained by random sampling regimes applied at light and electron microscopic levels. From electron micrographs the volume densities of euchromatin, heterochromatin, nucleoli, mitochondria, Golgi apparatus and rough endoplasmic reticulum were determined. Cell surface/volume ratios were also computed. By estimating mean nuclear volumes using light microscopy, it was possible to calculate absolute compartmental volumes and to evaluate the plasma membrane surface areas of average cells. Transformation in this model was characterized by a considerable cellular hypertrophy and a substantial increase in plasmalemma surface. Hypertrophy was the consequence of increases in the volumes of all measured intracellular compartments, notably euchromatin and “residual cytoplasm” (including ground cytoplasm and free ribosomes). These changes are discussed in the context of the altered metabolic status of cells.
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    Cell & tissue research 200 (1979), S. 193-203 
    ISSN: 1432-0878
    Keywords: Mosquitoes ; Midgut ; Ultrastructure ; Stereology ; Function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Morphometrische Untersuchungen des Magenepithels von A. aegypti weisen darauf hin, daß die Verdauung des ersten Blutmahls in eine Reihe von Phasen gegliedert werden kann, die sich mit physiologischen Daten aus der Literatur korrelieren lassen. In einer Phase Ia (0–10 h nach Blutmahl [BM]) entfalten sich die “whorls” des rauhen endoplasmatischen Retikulums, die Golgi-Zonen werden größer, und das basale Labyrinth wird erweitert. Dies stimmt mit Synthese- und Sekretionsprozessen (z.B. peritrophische Membran, Esterasen, Lipasen) und mit Transportvorgängen durch das Magenepithel überein. In Phase Ib (10–20 h nach BM) nehmen die gemessenen zellulären Parameter weiter zu und weisen damit auf hohe Synthese- und Sekretionsaktivitäten (z.B. Verdauungsenzyme) hin. In Phase Ic (20–30 h nach BM) zeigen die an Synthese und Sekretion beteiligten Zellstrukturen, in Übereinstimmung mit der maximalen Proteasenaktivität im Darm, immer noch hohe Werte. Vergrößerte Mikrovillioberfläche, auffallende Lipideinschlüsse und Auftreten von Glykogendepots im Magenepithel deuten auf erhöhte Resorptions-, Speicher- und Transportfunktionen der Zellen hin. In Phase II (30–36 h nach BM) läßt sich anhand der strukturellen Veränderungen der Wechsel von Synthese- und Sekretionvorgängen zu Resorption, teilweiser Speicherung und Transport von Verdauungsprodukten erkennen. In Phase III (36–72 h nach BM) wird der Zellapparat in Übereinstimmung mit dem Ende der Verdauung reduziert. Lipid- und Glykogendepots werden mobilisiert und verschwinden fast vollständig aus den Magenepithelzellen.
    Notes: Summary Morphometric analysis of the epithelial lining of the stomach of A. aegypti suggests that digestion of the first blood meal in the stomach of this species can be viewed as a series of phases that can be correlated with physiological data from the literature. In phase Ia (0–10 h after blood meal [abm]) the whorls of the rough endoplasmic reticulum unfold, the Golgi zones increase, and the basal labyrinth is enlarged. This coincides with processes of synthesis and secretion (e.g., peritrophic membrane, esterases and lipases) and transport by the stomach epithelium. In phase Ib (10–20 habm) the cellular parameters measured further increase, indicating high synthetic and secretory activities (e.g., digestive enzymes). In phase Ic (20–30 habm) cell structures involved in synthesis and secretion still exhibit high values coinciding with maximal activity of proteases in the gut. Enhanced surface area of microvilli, prominent lipid inclusions, and appearance of glycogen deposits in the gut epithelium suggest increased absorption, storage, and transport functions of the stomach cells. In phase II (30–36 habm) structural alteration points to a gradual shift from synthesis and secretion to absorption, partial storage, and transport of nutrients. In phase III (36–72 habm) the cellular apparatus is reduced concomitant with the ending of the digestive cycle. Lipid inclusions and glycogen deposits disappear from the stomach epithelum.
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    Cell & tissue research 200 (1979), S. 435-442 
    ISSN: 1432-0878
    Keywords: Fat body ; Calliphora ; Electron microscopy ; Cytochemistry ; Ecdysterone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the larval fat body of Calliphora erythrocephala, protein accumulation and autophagic activity occur prior to the onset of puparium formation. The involvement of the lysosomal system in the degradation of sequestered protein and cell organelles can be demonstrated by the electron microscopical cytochemical localization of the lysosomal marker enzyme acid phosphatase in so-called protein granules. These granules contain not only newly synthetized or absorbed protein but also remnants of cell organelles such as mitochondria and endoplasmic reticulum. Ligation of the larvae behind the brain-ring gland complex prevents the appearance of these acid phosphatase positive granules. They can be induced in ligated larvae by the injection of 20 hydroxyecdysone into the abdomen. These findings are briefly discussed in relation to the role of moulting hormones in normal development, especially with regard to the induction of autophagic activity.
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  • 165
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    Keywords: Lipid absorption ; Pyloric caeca ; Electron microscopy ; Feeding experiment ; Rainbow trout
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Rainbow trout were killed 4 and 18 h after being fed wax ester-rich marine Zooplankton and the absorptive epithelium of the pyloric caeca examined by electron microscopy. Numerous osmiophilic drops were seen in the lamina propria underlying the epithelium of fish killed at both times, but these drops were only abundant within columnar epithelial cells of fish killed 4 h after feeding. Pinocytotic profiles were not common at the luminal plasma membranes, nor were osmiophilic droplets seen in the terminal web area between the luminal plasma membrane and the extensive smooth endoplasmic reticulum. Numerous osmiophilic droplets, 30–100 nm in diameter, were present in the cisternae of the smooth endoplasmic reticulum with up to five separate droplets per individual cisterna. Columnar epithelial cells also contained up to 100 large osmiophilic drops (“conglomerates”) which tended to be concentrated in the supranuclear (Golgi) regions. The conglomerates were 250–1200 nm in diameter and were themselves made up of smaller droplets 30–400 nm in diameter. Conglomerates were present both within intracellular membranes and free in the cytoplasm. Osmiophilic droplets in the intercellular spaces and lamina propria were similar in size to individual droplets within conglomerates. We conclude that triacylglycerols are elaborated in the smooth endoplasmic reticulum, transferred to and processed in the Golgi region and finally discharged serosally as chylomicron-like particles of not greater than 400 nm diameter.
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    Cell & tissue research 198 (1979), S. 373-380 
    ISSN: 1432-0878
    Keywords: Ventral cochlear nucleus ; Calyceal processes ; Flattened synaptic vesicles ; Ultrastructure ; Morphometric study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In this paper we report the appearance of flat vesicle-containing endings in aldehyde-fixed ventral cochlear nucleus of rats with qualitative and quantitative properties suggesting they should be identified as calyceal processes. Their synaptic vesicles are elongate and significantly smaller than the vesicles in the calyces of Lenn and Reese (1966). Therefore these endings are flat vesicular calyceal processes, possibly of inhibitory function.
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    Cell & tissue research 198 (1979), S. 411-426 
    ISSN: 1432-0878
    Keywords: Intermediate lobe ; Hypophysis ; Ultrastructure ; Colour change ; Control mechanisms ; Anolis carolinensis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the intermediate lobe of the hypophysis was studied in Anolis carolinensis with the use of a threefold aldehyde fixative. Lizards with a brown skin were selected. The possibility of two types of secretory cells is discussed; neither cell type is innervated. Type I cells are rarely found and contain dense granules approximately 0.3 μm in diameter; Type II cells vary widely in secretory activity. Most of the Type II cells contain a large number of dense secretory granules (up to about 1.3 μm in diameter) almost filling the cytoplasm. Rough endoplasmic reticulum (RER), Golgi apparatus and mitochondria are poorly developed. Only some of these cells show signs suggesting a high secretory activity, namely a well developed RER, Golgi apparatus and numerous mitochondria. In these cells the RER sometimes forms large intracisternal droplets (up to 7 μm in diameter). Two of the animals exhibited a more uniform, high secretory activity. Large (about 2 μm in diameter), pale vacuoles, probably of extracellular character, were found mostly in the vicinity of the perivascular septum. Their role in the release of MSH is discussed. The present data, which are discussed with reference to earlier findings (Forbes, 1972), form the morphological basis for an experimental study on regulation of MSH release (Larsson et al., 1979).
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  • 168
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    Cell & tissue research 198 (1979), S. 477-486 
    ISSN: 1432-0878
    Keywords: Embryonic heart ; Myogenesis ; Sarcomere ; Crustacea (Homarus americanus) ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cardiomyoblasts in the myocardium of embryonic lobsters at 3–4 weeks and 6 months of development were examined with the transmission electron microscope in order to describe the events in the formation of sarcomeres in a neurogenic cardiac system. Thick and thin myofilaments appear first in the cell periphery near the sarcolemma. They align in parallel in a sequential fashion to form consecutive sarcomeric units. Well-defined A and I bands appear before any semblance of a Z line is present. The initial sarcomere is anchored to the sarcolemma by the insertion of thin myofilaments into a region of electron dense material associated intimately with the sarcolemma. Myofibrils grow outward in several planes away from the electron-dense regions of membrane that serve as focal points for myofibril formation.
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  • 169
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    Cell & tissue research 198 (1979), S. 455-463 
    ISSN: 1432-0878
    Keywords: Neuromuscular synapses ; Presynaptic density ; Ultrastructure ; Serial sections ; Crustaceans
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Representative examples of lowand high-output neuromuscular synapses between motoneuron and distal accessory flexor muscle of the lobster were selected on the basis of their mean quantal content, and subsequently analysed by serial section electron microscopy. The high-output terminal has twice as many synapses as the low-output terminal. However, since the mean surface area of synapses is significantly smaller in the high-output terminal than in the low-output one, the total synaptic surface area between the two types of terminals is similar. Also, though the high-output terminal possesses a greater number of presynaptic dense bodies than its low-output counterpart, the mean number per synapse is similar for the two terminals. The terminals, however, differ significantly in the size of their dense bodies. Thus both the mean and total surface area of these bodies is greater in the high-output terminal than in the low-output one. Moreover, the mean ratio of dense body area to synaptic area is significantly greater for the high-output terminal than for its low-output counterpart. This difference in dense body area parallels the difference in quantal content of synaptic transmission between the lowand high-output terminals and supports the hypothesis that presynaptic densities represent the ultrastructural correlates of transmitter mobilization and/or release.
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  • 170
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    Cell & tissue research 198 (1979), S. 521-526 
    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Electron microscopy ; L-DOPA ; Lysosomes ; Chinese quail, Excalfactoria chinensis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Intraperitoneally injected L-DOPA was found to stimulate strongly the lysosomal system of all of the cell types of the adenohypophysis. We suggest that this amine may play a role in the regulation of the secretory activity of the gland by mediating the lysosomal activity, this role being of variable importance according to the fluctuations in hormonal activity. Ultrastructural changes occur in some cell types following injection of L-DOPA. The question as to whether these changes are induced directly by L-DOPA or via the monoaminergic system of the hypothalamus and its hypophysiotropic hormones is discussed.
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  • 171
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    Cell & tissue research 199 (1979), S. 483-492 
    ISSN: 1432-0878
    Keywords: Pituitary gland ; Rat ; Luteotroph cells ; Pimozide ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of pimozide, a dopamine receptor-blocking agent, were studied in the pars distalis of the rat. The animals received 100μg/100 g pimozide daily for 5, 10, 15, and 20 days. Pimozide induces striking ultrastructural changes after 5 days of treatment. The number of luteotroph (LTH) cells is significantly increased; they display characteristics of stimulation. The extrusion of granules into the intercellular space via exocytosis is frequently observed. The intercellular spaces are highly dilated, forming a lacunar system filled with an amorphous material, erythrocytes and involuted LTH cells. Transitional stages in the process of involution are observed in LTH cells. Luteotroph cells also form a syncytium. Twenty days after treatment the abovedescribed changes decrease in magnitude. The present findings suggest that pimozide stimulates the mechanism of synthesis and release in the luteotroph cells, an effect that is less evident with longer treatment.
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  • 172
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    Cell & tissue research 199 (1979), S. 509-517 
    ISSN: 1432-0878
    Keywords: Olfactory bulb ; Giant cells ; Neurosecretion ; Electron microscopy ; Labyrinth fish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The giant cells in the olfactory bulb of labyrinth fish, most likely belonging to the nervus terminalis, show ultrastructural features of active synthesis of secretory material. Dense core vesicles (70–100 nm in diameter), found in the perikaryon as well as in the axon, are the possible storage sites of the secretory substance. Its chemical nature is unknown. In some of these vesicles acid phosphatase is demonstrable. Large membrane-bound bodies (up to 2000 nm in diameter), either containing an electron dense matrix or debris of cytoplasmic organelles, are also acid phosphatase-positive, suggesting their lysosomal nature. Some other ultrastructural characteristics of these cells are also described.
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  • 173
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    Cell & tissue research 199 (1979), S. 519-528 
    ISSN: 1432-0878
    Keywords: Filum terminale ; Spinal cord ; Glial cells ; Ultrastructure ; Frog (Rana pipiens)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The filum terminale, or terminal portion of the spinal cord, was studied in normal adult frogs (Rana pipiens) by means of light and electron microscopy. Astroglial cells are the predominant elements in this region. The rostral portion of the filum terminale consists mainly of (1) a peripheral dense ring of myelinated and some unmyelinated nerve fibers, and processes of astrocytes terminating at the subpial space; (2) an intermediate zone, in which astrocytes are the main cellular elements in addition to a few degenerated neurons; and (3) a central region where the central canal is lined by dark and light ependymal cells. In the caudal portion of the filum terminale, the amount of neuropil is greatly reduced. This region is formed mainly by astrocytic glial cells and very few neuronal elements. The central canal in the caudal portion is located ventrally and contains a lining consisting almost exclusively of dark ependymal cells.
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  • 174
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    Keywords: Pars distalis ; Graft ; Ultrastructure ; Prolactin ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Intact female rats received transplants of two hypophysial partes distales under the kidney capsule. The plasma levels of prolactin were determined, and the ultrastructure of the grafted gland was studied 15, 45 and 90 days after the operation. Although prolactin levels in the three experimental groups were significantly higher than those in control rats, a decrease in prolactin level was detected in the 45-day samples. Parallel ultrastructural changes suggest that between the 45th and 90th postoperative day a process is initiated leading to hyperplasia and hypertrophy of prolactotrophs.
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  • 175
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    Cell & tissue research 201 (1979), S. 145-158 
    ISSN: 1432-0878
    Keywords: Ultrastructure ; Secretory granules ; Endosalpinx ; Sheep
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of granules in the secretory cells of the endosalpinx of 20 Merino ewes was examined on days 1, 2, 3, and 4 post coitum. Based on the different frequency of granules of different size and structure on days one to four post coitum, one can assume that the ovoid, membrane bounded secretory granules mature in five successive stages. In stage I small, electron-lucent vesicles with a finely granulated and filamentous content become apparent, initially in the neighbourhood of the Golgi complex. In stage II the granules become larger and progressively more eletron-dense by an increase of the granulated material. In stage III, the primarily granulated content forms membranes, that lie in characteristic stacks at different angles to one another, separated by electron-dense areas. This structure fragments when the granule comes to lie beneath the surface of the cell (stage IV) and opens into the lumen of the oviduct, where its content is discharged in membrane fragments or vesicles (stage V). This discharge is mainly observed shortly before the egg is transported into the uterus.
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  • 176
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    Cell & tissue research 201 (1979), S. 159-163 
    ISSN: 1432-0878
    Keywords: Insulin secretion ; Acid-base changes ; Electron microscopy ; Pancreas perfusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural changes in pancreatic β cells were studied following glucose-induced insulin secretion in vitro, at two different extracellular pH (7.4 and 7.8). The pancreata perfused at pH 7.4 exhibited a biphasic insulin response to glucose challenge together with signs of increased emiocytotic activity and numerous microtubules in the β cells. Conversely, the pancreata perfused at pH 7.8 showed a significant decrease in insulin secretion, and their β cells revealed scarce emiocytotic images and a marked increase of intracellular granulolysis. These results represent the ultrastructural correlate of the reduced insulin secretion produced by metabolic alkalosis in the perfused rat pancreas.
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  • 177
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    Keywords: Adrenal cortex ; Steroid release ; Rabbit ; Electron microscopy ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the rabbit adrenal cortex was investigated. The parenchymal cells display the ultrastructural features of steroid-producing cells, and also contain numerous electron-dense bodies frequently located near intercellular canaliculi, which open into the subendothelial space. Short-term ACTH-administration induced a noticeable decrease in the volume of the lipid compartment in the cells of all three cortical zones and a significant increase in the volume of dense bodies in the cells of zona fasciculata and zona reticularis. The hypothesis that these dense bodies are secretory granules is discussed in the light of biochemical evidence showing that ACTH increases the concentration of both corticosterone and cortisol in the decapsulated-enucleated adrenal homogenate and does not affect the activity of two lysosome-marker enzymes (i.e., acid phosphatase and β-glucuronidase).
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  • 178
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    Cell & tissue research 202 (1979), S. 479-491 
    ISSN: 1432-0878
    Keywords: Ependyma ; Ultrastructure ; Posterior tela choroidea ; Rhombencephalon ; Rana catesbeiana
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The posterior rhombencephalic tela choroidea of the bullfrog was examined by electron microscopy. This membrane, the pia-ependymal roof of the caudal hindbrain, contains a large central region characterized by cuboidal ependymal cells which surround sizable microscopic apertures — the interependymal pores. Ultrastructurally ependymal cells of this area are characterized by infrequent apical microvilli and cilia. They contain irregularly shaped nuclei and few cytoplasmic organelles that are largely apical in position. The most striking feature is an abundance of cytoplasmic filaments forming an extensive cytoskeleton. Laterally these cells are joined by numerous elaborate desmosomes. The majority of the ependymal cells have a basal lamina consisting of single, double, or triple laminae lying parallel to the basal plasma membrane. Several unusual specializations are seen at the margins of the interependymal pores. The ependymal cells have lateral cytoplasmic processes that form the actual border of each pore. These processes originate from the apical surface of the cell and partially enclose an elaborate network of basal lamina associated with the interependymal pores. These findings demonstrate microscopic apertures in the roof of the fourth ventricle in the bullfrog that are associated with an unusual form of supportive ependyma.
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  • 179
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    Cell & tissue research 199 (1979), S. 1-23 
    ISSN: 1432-0878
    Keywords: Neuro-intermediate lobe ; Hypophysis ; Disconnection ; Ultrastructure ; Colour change ; Control mechanisms ; Anolis carolinensis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Morphological changes in the disconnected neuro-intermediate lobe were studied in the lizard, Anolis carolinensis from the 2nd to the 14th post-operative day using a threefold aldehyde fixative (Rodríguez, 1969). Two phases of colour change capacity were exhibited: Phase I started immediately after the transection, lasted for 6 days (mean) and was characterised by an excessive MSH release (brown skin). This phase proceeded gradually into Phase II, designated by an interruption of the MSH release (green skin). The degenerative processes and final elimination of neurons in the disconnected neural lobe propagate in a rostro-caudal direction from the transected area. The aminergic fibres (Type II) disappear within 2 days postoperatively, whereas the degeneration continues for more than 10 days in the peptidergic fibres (Type III, IV and V). The glia cells (ependyma and pituicytes) serve as very active macrophages, engulfing fragments of axons already affected by autolysis and transferring them into glial lysosomes. No apparent morphological changes occur in the shift from Phase I to II. The great majority of the secretory cells of the intermediate lobe are not affected by degenerative processes and appear to be markedly activated by the stalk transection. They exhibit numerous mitochondria, well-developed Golgi complexes forming numerous Golgi vesicles and extensive parallel cisternae of the rough endoplasmic reticulum, sometimes forming large intracisternal droplets (7 μm in diameter). Numerous pale vacuoles are seen, especially toward the intact capillaries, suggesting their coupling to the MSH release by extension of the active membrane area toward the perivascular septum. The number of these vacuoles is very markedly reduced in Phase II (no release), whereas the formation of new granules seems to proceed in early stages. The interruption of the MSH release implies a successive refilling of gradually growing secretory granules and a concomitant reduction in the development of the synthetic apparatus. Mechanisms probably involved in the control of the synthesis and release of MSH are discussed.
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  • 180
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    Cell & tissue research 199 (1979), S. 37-61 
    ISSN: 1432-0878
    Keywords: Avian thymus ; Ultrastructure ; Erythropoiesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Thymus lobes from three species of birds, Quelea quelea, Passer domesticus and Sturnus vulgaris, have been examined ultrastructurally. The component cell types are compared with their counterparts in mammalian thymus glands, and found to be similar. Greater differences exist between small, intermediate and enlarged lobes of one species than exist between species. Developing erythroid cells are present in most enlarging and some enlarged glands. They appear to be developing at the expense of lymphoid cells in some birds. The origin of these cells is discussed. Cells that are possible candidates for the production of some thymic hormones are also described.
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  • 181
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    Keywords: Haemocytes ; Phagocytosis ; Lysosomes ; Acid phosphatase ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The plasmatocytes are the major phagocytic blood-cell type in the haemolymph of the wax-moth, Galleria mellonella. In the present study, these cells were allowed to attach to tissue culture dishes for 1 h, rinsed and then incubated with latex beads for up to 72 h. These cells were then fixed for routine transmission electron microscopy and acid phosphatase cytochemistry. Intracellular latex particles were found in tight, ill-defined phagosomes, which were often clearly associated with the Golgi complexes of the plasmatocytes. Fusion of both primary lysosomes and multivesicular bodies with the phagosomes occasionally occurred and this resulted in the accumulation of an acid phosphatase positive reaction product around the test particles. Subsequent experiments showed that this acid phosphatase activity was mainly associated with the primary lysosomes. The results of the lysosome/latex interactions are compared with those obtained from similar studies on the digestive mechanisms in other phagocytes.
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  • 182
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    Cell & tissue research 199 (1979), S. 171-175 
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    Keywords: Crustaceans ; Neuromuscular synapse ; Multiterminal innervation ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of nerve terminals from a single excitatory motor axon has been followed along a fiber from the proximal accessory flexor muscle of the lobster by thin serial sectioning at periodic intervals. The excitatory motor axon provides small axonal branches (diameter 5–12 μm) of varying lengths that travel along the surface of the muscle fiber. Each of these branches gives rise to discrete synaptic terminals which are not uniformly distributed. Individual terminals vary in length from 10–60 μm and the majority possess neuromuscular synapses. The greatest distance between synapses is slightly over 1 mm which is well within the length constant (2.6 mm) of this muscle fiber. Thus the spatial distribution of synapses is such as to ensure adequate depolarization along the entire length of the muscle fiber.
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  • 183
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    Cell & tissue research 199 (1979), S. 257-270 
    ISSN: 1432-0878
    Keywords: Liver ; Bile duct ligation ; Tight junctions ; Gap junctions ; Ultrastructure ; Freeze-fracturing ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Morphometric analysis of the alterations in interhepatocyte junctions induced by bile duct ligation revealed that after 48 h, during which time the serum bilirubin increased 6 to 8 fold, the membrane area occupied by gap junctions on the apico-lateral and medio-lateral sides decreased from 3.6% in controls to 0.02% in the ligated group. The strands of the zonulae occludentes were reduced in number and showed increased discontinuities. Within 45 min of recanalization of the common bile duct, clusters of particles appeared within and adjacent to the tight junctional areas or in the lateral hepatocyte membrane. Subsequently, the particle aggregations localized in the apico-lateral membrane areas increased in number and size becoming finally indistinguishable from those of controls within 96 h after the onset of recanalization. The zonulae occludentes also rearranged and reestablished their original structure during this period. The serum bilirubin fell to normal within 24 h of recanalization. It is concluded that metabolic and ultrastructural restitution associated with the recanalization of the ligated bile duct have no strict temporal correlation to one another. These studies provide further evidence that alterations in gap and tight junctions induced by pathological processes, e.g. during bile duct ligation, are completely reversible when regeneration occurs.
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    Cell & tissue research 199 (1979), S. 281-288 
    ISSN: 1432-0878
    Keywords: Annular microtubules ; Nodes of Ranvier ; Nerve ; Axon ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Using a special albumin technique, nodes of Ranvier have been examined within frog skeletal muscle, sciatic nerve and rat and frog cerebrum. Initial segments have been examined in cerebrum of frog and rat. Microtubules usually run longitudinally through these regions, but within the bare area of the intramuscular node of Ranvier, annular or helical bundles of microtubules run in a marginal band at right angles to the more centrally placed longitudinal microtubules. These nodal bare areas show a pronounced convexity and it is suggested that the annular microtubules serve to maintain this convexity during muscle contraction.
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  • 185
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    Cell & tissue research 199 (1979), S. 373-386 
    ISSN: 1432-0878
    Keywords: Hypogastric ganglion (rat) ; Vacuolated neurons ; Catecholamine fluorophore ; Ultrastructure ; Testosterone ; Castration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The vacuolated neurons (VN) of the main hypogastric ganglion of the male rat were studied using the formaldehyde-induced fluorescence (FIF) method for the histochemical demonstration of catecholamines. Microspectrofluorimetry was performed to identify the fluorophores and to quantify the FIF. The thiocholine method (Koelle-Gomori) was used to demonstrate acetylcholinesterase activity. The fine structure of the VN was studied using glutaraldehyde/OsO4 fixation. (1) In the untreated adult male rat VN represent only a small population of the total number of hypogastric neurons (0.8–1.2%). The vacuoles are similar to those of the VN from the corresponding female ganglion. (2) The VN are considered to be adrenergic due to the nature of their fluorophore, indicating a primary catecholamine. (3) The first VN appear in the hypogastric ganglia at the age of 7 weeks. After testosterone administration to young rats, VN are found at the age of 4 weeks. (4) The basic fine structure of the VN is similar to that of other ordinary neurons of the hypogastric ganglia. (5) The content of the vacuoles could not be identified. (6) Indications of degeneration were not observed in the VN. (7) The VN are interpreted as being a functional stage of the “short” adrenergic neurons, which are under the control of steroid hormones. (8) Fifteen months after castration, no VN could be found in the hypogastric ganglia, while their number was normal in the corresponding control animals.
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  • 186
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    Cell & tissue research 201 (1979), S. 37-44 
    ISSN: 1432-0878
    Keywords: Brush cell ; Receptor ; Lateral microvilli ; Gallbladder ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The brush cells of the gallbladder epithelium of the mouse have microvilli not only at their luminal border but also on their lateral surface, from the level of the nucleus to the junctional complex. The lateral microvilli radiate from the brush cell in all directions, contain a core of filaments, and penetrate up to 3 μm into the adjacent cells. The microvilli in these locations display small desmosomes at their base.
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  • 187
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    Cell & tissue research 201 (1979), S. 305-314 
    ISSN: 1432-0878
    Keywords: Cockroach ; Muscle heterogeneity ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural studies have been performed upon the posterior coxal depressor muscle (136) and a coxal branch of the main depressor group (135d′) from the mesocoxa of the cockroach, Periplaneta americana. The quantitative stereometric analyses performed have shown the latter muscle to consist of a dorsal band of fibers having 25.5% mitochondria and 13.6% sarcoplasmic reticulum (SR) and T-tubules (TTS), and a ventral group of fibers with only 4.4% mitochondria and 26.6% SR/TTS. The volume fractions characteristic of the ventral fibers of muscle 135 d′ are also typical of muscle 136.
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  • 188
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    Cell & tissue research 201 (1979), S. 369-376 
    ISSN: 1432-0878
    Keywords: Leydig cells ; Filaments ; Golden hamster ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A unique cytoplasmic structure has been observed in Leydig cells of the golden hamster. It consists of a laminar core made up of electron dense material surrounded by a filamentous matrix of lower density, and is tentatively called a dense-cored filamentous body (DCFB). DCFBs vary in overall size and in configuration of the centrally disposed dense lamina. They are typically located in the vicinity of the centrosome and the Golgi complex. The body has no limiting membrane, and may be in contact with virtually every type of organelle. The DCFB is well developed in active Leydig cells, whereas it is small in the quiescent stage of the secretory cell. It is likely that the DCFB is a constant organelle in the hamster Leydig cell and may be involved in the physiological function of the Leydig cell, which remains to be specified.
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  • 189
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    Cell & tissue research 201 (1979), S. 451-458 
    ISSN: 1432-0878
    Keywords: Epididymis ; Freeze-fracture ; Electron microscopy ; Male reproduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The epithelium of the monkey epididymis was studied by means of freeze-fracture techniques and conventional electron microscopy. For the study of transepithelial permeability lanthanum hydroxide was used as an intercellular tracer. The epididymal epithelium consists mainly of tall columnar cells. The long stereocilia at the apical surface, similarly to microvilli, exhibit after freeze-fracture, two distinct faces: the E face, concave and with fewer membrane-associated particles, and the complementary convex P face. In the lumen unusual groups of smooth-surfaced vacuoles are present. A tight junctional network, which shows some permeability to the lanthanum tracer, is located at the apical end of the cells. Supranuclear cross-fractures clearly show the well developed Golgi cisternae and numerous vacuole profiles. The highly infolded, centrally located nucleus exhibits, after freeze-fracture, an even distribution of nuclear pores. In the perinuclear region the rough endoplasmic reticulum, which also presents pores, displays a sheet-like organization. The basal cytoplasm is filled by numerous globular profiles of membrane-bounded granules. Freeze-cleave exposes large cytoplasmic areas where the types and amount of organelles indicate an intense metabolic activity.
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  • 190
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    Cell & tissue research 201 (1979), S. 467-477 
    ISSN: 1432-0878
    Keywords: Anterior pituitary ; Hormone synthesis ; Morphometry ; Autoradiography ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In order to compare the functional state of the anterior pituitary of spontaneously hypertensive rats (SHR) with that of normotensive Wistar Kyoto rats (WKR), the anterior pituitary was examined by morphometry and autoradiography at the level of electron microscopy. The relative number and the relative volume of thyrotrophs in the anterior pituitary were significantly greater in SHR compared with age-matched WKR at 0, 7, 30–33 days, and 10 months of age, while the relative number of somatotrophs in SHR was significantly smaller at 1 and 10 months of age. Electron microscope autoradiographic analysis of uptake of 3H-lysine by thyrotrophs of both strains at the age of approximately one month showed that 3H-lysine was incorporated into protein and transported finally to secretory granules which migrated to near the cell membrane to be discharged. Silver grains were significantly more numerous over the thyrotrophs of SHR than over those of WKR at 30 min, 1 h, and 4h after the injection of 3H-lysine. The present study has ascertained morphologically that a congenital hypersynthesis of TSH by the anterior pituitary occurs in SHR.
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    Cell & tissue research 202 (1979), S. 125-132 
    ISSN: 1432-0878
    Keywords: Macrophage ; Osteoclast ; Bone resorption ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural observations on macrophage-mediated resorption of calcified tissue of killed fetal long bones are described and correlated with increased 45Ca release into the medium. Macrophages disrupt calcified tissue extracellularly and appear to engulf large fragments of mineralized matrix. Ruffled borders, which are common features of osteoclasts at sites of resorption of bone, do not develop in macrophages. However, clear zones are seen in macrophages as well as osteoclasts. These findings provide additional evidence for non-osteoclast-mediated resorption of calcified tissue.
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    Cell & tissue research 202 (1979), S. 203-212 
    ISSN: 1432-0878
    Keywords: Mineralization processes ; Scales ; Teleost fish ; Matrix vesicles ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In Teleost fish scales, growth and mineralization are continuous. Different mineralization processes can be distinguished. The external layer of the scale is the first to be mineralized and may be classified as the initial calcifying structure of the scale. The initial calcification loci are matrix vesicles of cellular origin always observed during the formation of this layer. This mineralization process takes place progressively, closely following the elaboration of the organic matrix in the scale periphery. The outer limiting and internal layers of the scale are developed after the external layer has been formed. A mineral substance is deposited without the mediation of matrix vesicles, but in contact with the previously mineralized external layer. This type of mineralization is called subsequential. However, the mineralization of the outer limiting layer closely follows the secretion of a collagen-free organic matrix and is thus different from the mineralization of the internal layer in which the calcification front remains remote from the collagen matrix surface and corresponds to a delayed mineralization process. The isolated calcifications (Mandl's corpuscles) which develop in the unmineralized laminae of the internal layer are mineralized in the absence of matrix vesicles and without making contact with a pre-existing calcified tissue, probably by a heterogeneous nucleation of the collagen fibrils.
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  • 193
    ISSN: 1432-0878
    Keywords: Pancreatic endocrine cells ; Enteroendocrine cells ; Ultrastructure ; Cyprinidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pancreatic endocrine cells of Barbus conchonius are concentrated in a large (principal) islet, located near the gall bladder, and in a number of smaller islets. Five types of endocrine cells can be distinguished in these pancreatic islets: B cells, A1 (or D cells), 2 types of A2 cells (A2r cells with round granules; and A2fl cells with flocculent granules) and a scarce 5th cell type. The hormones produced by B and A2fl cells are probably insulin and glucagon respectively. The A2r cell contains granules with the same diameter as the granules of the enteroendocrine type III cell of the gut. Both cell types may resemble the enteroglucagon-producing EG cell of mammals. The function of the A1 cells, which are frequently found without secretory granules, and of the 5th cell type, will be discussed. The pancreatic islets of B. conchonius are strongly innervated, which suggests the presence of a direct nervous control system. Some intermediate or mixed cells containing exocrine and endocrine A2r granules are found contiguous with the principal islet. The origin of pancreatic endocrine cells is also the subject of discussion.
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  • 194
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    Cell & tissue research 199 (1979), S. 249-256 
    ISSN: 1432-0878
    Keywords: Hepatocytes ; Birds ; Ultrastructure ; Estrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Administration of estradiol-17-β induces the synthesis of vitellogenin in primary cultures of chick embryo liver. The ultrastructural changes accompanying steroid induced vitellogenin synthesis were investigated in hepatocytes cultures incubated for 0, 12 and 24 h following hormonal treatment. Both electron microscopy and immuno-chemical techniques were used. The immuno-fluorescence data indicate that the cultures contain a cell population of 90–95% hepatocytes, both in control and estradiol-treated groups. Ultrastructurally, cultured hepatocytes are similar to in vivo ones, except for a reduced accumulation of storage materials, glycogen and lipids. In the estradiol-treated cultures hepatocytes show an accumulation of free ribosomes, enlargement of rough endoplasmic reticulum, and development of the Golgi apparatus. The data are discussed in relation to previous biochemical findings.
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  • 195
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    Cell & tissue research 201 (1979), S. 101-127 
    ISSN: 1432-0878
    Keywords: T-lymphocytes ; Cell activation ; Stereology ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Stereological data of phytohaemagglutinin (PHA)-activated human T-lymphocytes were recorded at intervals (12 to 72 h) together with biochemical (isotope-uptake, lymphotoxin-release) and morphological measurements. About 98 % of the cells were activated 12 h after PHA-stimulation. The activation phase lasted less than 48 h, i.e., cells entering the activation phase within 12 h were at their activation maximum by 48 h. The activated cell increased in size. The nuclear/cytoplasmic-ratio decreased. Most of the cytoplasmic organelles developed in phase with the increase of cytoplasmic volume. After 48 h, mitotic figures were frequently seen. Due to the increasing number of secondary, activated daughter cells, parameters of most cytoplasmic components declined between 48 and 72 h. Structural changes in the nucleus preceded the 3H-leucine uptake, which had not reached its maximum after 72 h of incubation. The 3H-leucine uptake started as early as 12 h after culture initiation, and its increase was proportional to the increasing polyribosome density. No maximum uptake was reached up to 72 h, but the development of structural components related to this uptake was at its maximum at the end of the activation phase (48 h). The formation of bound ribosomes occurred subsequent to the enlargement of the surface of the rough endoplasmic reticulum. Initial polysome formation occurred at the expense of existing free ribosomes.
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  • 196
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    Cell & tissue research 201 (1979), S. 459-466 
    ISSN: 1432-0878
    Keywords: Electron microscopy ; Collagen ; Cuticle ; Lumbricus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A method has been developed to isolate and purify cuticular fibrils of Lumbricus. Polarizing microscopy confirms the collagenous nature of the isolated fibrils. Study in the electron microscope of isolated fibrils, negatively or positively stained, shows that they are cylindrical, unbranching and without periodic structure. Enzymatic treatment of cuticles with alpha-amylase and trypsin results in a more or less complete dissociation of the fibrils which appear clearly to be made up of helically wound bundles of filaments (30–40 Å). The structure of the cuticular fibrils is discussed in relation to biochemical and biophysical data and compared to the ultrastructural organization of other periodically cross-banded fibrils.
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  • 197
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    Cell & tissue research 201 (1979), S. 479-486 
    ISSN: 1432-0878
    Keywords: Ultrastructure ; Cercaria ; Striated tail muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The electron microscopic study of the tail of Cercaria chackai reveals that it contains four sets of striated muscle bundles located central to the nonstriated circular and longitudinal muscles. The striated muscle consists of longitudinally oriented lamellar myofibres. Each myofibre contains a single “U” shaped myofibril. The banding pattern is analogous to that of vertebrate striated muscle. The sarcolemma is a simple surface membrane. There are no transverse tubular extensions of sarcolemma. The sarcoplasmic reticulum (SR) is very well developed with cisternae, tubules, and vesicles. SR cisternae form dyadic couplings with the sarcolemma. There is a set of flattened tubules of SR origin traversing the myofibril exactly at the Z region. These tubules are unique to the striated muscle of the cercarian tail and may have functional significance. A diagrammatic reconstruction of the myofibre is presented.
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  • 198
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    Cell & tissue research 202 (1979), S. 133-143 
    ISSN: 1432-0878
    Keywords: Oogenesis ; Yolk formation ; Nurse cells ; Ultrastructure ; Diplura
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The egg chamber of Campodea consists of a group of nurse cells and an oocyte, and is surrounded by a simple, markedly flattened follicular epithelium. Three types of yolk occur in the oocytes: type I appears within elements of the rough endoplasmic reticulum; type II is produced by specific complexes of endoplasmic reticulum and dictyosomes; type III is incorporated by micropinocytosis. Histochemical tests show that mature yolk spheres contain proteins and polysaccharides. The main function of the nurse cells is to synthesize RNA, but they also produce small amounts of type I yolk. Phylogenetic conclusions are drawn from this and other studies of oogenesis in apterygote insects.
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  • 199
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    Cell & tissue research 202 (1979), S. 145-153 
    ISSN: 1432-0878
    Keywords: Oogenesis ; Yolk formation ; Ultrastructure ; Symphyla
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The paired ovaries of Symphyla are sac-shaped. Their interior is filled with synchronously developing oocytes surrounded by a simple follicular epithelium. Previtellogenic oocytes have spherical or oval nuclei, the latter containing a large number of small nucleoli. Part of the nuclear surface is covered by a thick “coat” made up of a granular substance of medium electron density. The “coat” is penetrated by cisternae of the smooth endoplasmic reticulum. Micropinocytosis is the principal source of yolk in Symphyla; a small amount of yolk material arises within the mitochondrial cristae. Vitellogenic oocytes are characterized by a highly active rough endoplasmic reticulum synthesizing a material, probably lipoprotein in nature, which is incorporated into lipid droplets.
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  • 200
    ISSN: 1432-0878
    Keywords: Lymph (pig) ; Langerhans cells ; Phase contrast microscopy ; Histochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Large mononuclear cells with long, actively moving cytoplasmic veils were observed in lymph coming from the skin. The enzyme histochemistry and ultrastructure of these cells suggested that they are related to epidermal Langerhans cells and interdigitating cells in the lymph node. It has been reported that Langerhans cells and interdigitating cells play a role in contact hypersensitivity by taking up antigen and presenting it to thymus-dependent lymphocytes, and it is likely that the veiled cells in the lymph are also involved. After skin-painting with 1-fluoro-2,4-dinitrobenzene (DNFB), the veiled cells in lymph coming from the site of painting became more active and were observed contacting other cells present in the lymph; many large cellular aggregates were found. Since neutrophilic leucocytes and mononuclear phagocytes were the predominating cell types in this lymph, there was no evidence for a massive recruitment of immunocompetent lymphocytes at the site of painting. Neonatally thymectomized pigs do not develop allergic reactivity to DNFB. It is of interest that the number of veiled cells and their ability to form large cellular aggregates was not affected in these animals. Therefore, it is unlikely that the defect in responsiveness can be attributed to a failure in the function of veiled cells.
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