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  • 1970-1974  (114)
  • 1965-1969  (3)
  • 1930-1934
  • 1890-1899
  • 1974  (114)
  • 1967  (3)
  • Electron microscopy  (117)
Datenquelle
Materialart
Erscheinungszeitraum
  • 1970-1974  (114)
  • 1965-1969  (3)
  • 1930-1934
  • 1890-1899
Jahr
Schlagwörter
  • 101
    Digitale Medien
    Digitale Medien
    Similarities between Hassall's corpuscles of the human thymus and the epidermis (1974)
    Springer
    Cell & tissue research 151 (1974), S. 347-368 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Human thymus ; Hassall's corpuscles ; Histochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Substrate-histochemical, enzyme-hystochemical and ultrastructural investigations were performed on thymic tissue from children, obtained in heart operations. β-Amylaseresistant, PAS-positive and Hale-positive substrates presumably neutral and acid mucosubstances, can be demonstrated in the central concentric lamellae of Hassall's corpuscles (HC). These lamellae also give positive reactions for sulphydryl groups and disulphide groups. Some flattened cell elements gave strong reactions for phospholipids, and small sudanophilic droplets, presumably neutral fats, are scattered throughout the HC. All investigated hydrolases and dehydrogenases either give no or only very weak reactions in the central part of progressive HC, but react strongly positive in their peripheral hypertrophic epithelial cells. In the central part of regressive HC, positive reactions for acid phosphatase and β-D-glucuronidase were recognized. These lysosomal enzymes may indicate degenerative processes. By electron microscopy progressive HC show central concentric lamellae with an amorphous matrix tightly filled with tonofilaments. They are surrounded by a thickened plasma membrane (200 Å), and do not contain nuclei. These central lamellae resemble the horny cells of the epidermis. The peripheral hypertrophic epithelial cells have pale nuclei with one or two nucleoli. Their cytoplasm contains numerous tonofibrils. These cells resemble stratum spinosum cells of the epidermis. In regressive HC the central concentric lamellae loose their intercellular contacts. The widened intercellular spaces are filled with cellular debris, and are invaded by macrophages. Similarities between the ultrastructure and the patterns of the histochemically investigated substrates and enzymes in human HC and epidermis are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00224546
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  • 102
    Digitale Medien
    Digitale Medien
    Studies on the juxtaglomerular apparatus (1974)
    Springer
    Cell & tissue research 151 (1974), S. 471-480 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Juxtaglomerular apparatus ; Rat ; Influence of deoxycorticosterone (DOC) ; Electron microscopy ; Morphometric analysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die quantitativ-morphologische Analyse des juxtaglomerulären Apparates nach DOC-Behandlung zeigte, daß mit der Hemmung der Reninbildung eine Hypoplasie der epitheloiden Zellen des juxtaglomerulären Apparates einhergeht. Der Granulagehalt der juxtaglomerulären Zellen nahm ab; die Kern-Plasma-Relation änderte sich und die Leiomyofibrillen in den Epitheloidzellen nahmen zu. An den übrigen Anteilen des juxtaglomerulären Apparates, insbesondere der Macula densa, wurden keine morphologischen Veränderungen beobachtet. Die DOC-Behandlung führte darüber hinaus zu einer Bildung von Einschlüssen in den Podocyten, den Mesangiumzellen und den Zellen der Bowman-Membran. Die verschiedenen Möglichkeiten, über welche Faktoren die juxtaglomerulären Zellen nach DOC-Behandlung degranuliert werden, werden diskutiert. Das ultrastrukturelle Bild der Epitheloidzellen nach DOC-Behandlung entspricht deutlich einer gehemmten Sekretion, da das Ergastoplasma und der Golgi-Apparat ganz besonders stark zurückgebildet werden.
    Notizen: Summary Quantitative morphological analysis of the Juxtaglomerular apparatus of rats treated with deoxycorticosterone (DOC) and salt revealed hypoplasia of the epithelioid cells as a concomitant of the inhibition of renin synthesis. The granular content of the Juxtaglomerular cells was significantly decreased, while the nucleus-to-cytoplasm ratio and the volume density of leiomyofilaments in the epithelioid cells increased. No morphological alterations were observed in the remaining constituents of the Juxtaglomerular apparatus, including the macula densa. DOC-treatment also induced the appearance of inclusions in the podocytes in the cells of the mesangium, and in the cells of Bowman's capsule. The possible mechanisms of degranulation of the Juxtaglomerular cells after treatment with DOC are discussed. The ultrastructural appearance of the epithelioid cells after treatment with DOC corresponds to an inhibition of secretion, since the rough endoplasmic reticulum and the Golgi apparatus undergo marked regressive changes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00222992
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  • 103
    Digitale Medien
    Digitale Medien
    The reaggregation of neurons and their satellite cells in cultures of trypsin-dissociated spinal ganglia (1974)
    Springer
    Cell & tissue research 152 (1974), S. 175-183 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Cell aggregation ; Spinal ganglia ; Cell cultures ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Dorsal root spinal ganglia of chick embryos were trypsinized and the cellular components isolated. Suspensions of these cells reaggregate. During this process satellite glial cells and neurons established intimate contacts. The reconstructed glial envelopes around the neurons are morphologically similar to the ones formed in the intact animal during development. The formation of the characteristic glial-neuronal relation is an example of specific cell recognition.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00224693
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  • 104
    Digitale Medien
    Digitale Medien
    The interaction of phagocytes and the large-sized parasite Cryptococcus neoformans: Cytochemical and ultrastructural study (1974)
    Springer
    Cell & tissue research 152 (1974), S. 165-174 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Phagocytosis ; Large foreign bodies ; Cryptococcus neoformans ; Tissue culture ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The yeast Cryptococcus neoformans may develop under certain conditions a large polysaccharide capsule 50–100 μM in diameter and therefore cannot be phagocytosed by either polymorphonuclear cells (PMN's) or mononuclear phagocytes (MN's). The cellular defense mechanism — in various animals — against the yeast is composed by formation of ringlike structure of PMN's or MN's cells which surround the C. neoformans. Ring structures develop either in vivo or in vitro in tissue culture; destruction of the yeast occurs within 36–72 hours. Several hydrolases, such as acid phosphatase, β-glucuronidase and non-specific esterase were found to be released from the phagocytic cells into the enclosed yeast. Considerable reduction of NBT used as a marker for oxidative activity was observed in MN rings at contact regions of the MN cells and the yeast. Electron microscopic studies indicate that the phagocytic cells in the ring structure have many pseudopodes penetrating into the polysaccharide capsule of the yeast. Disintegration of the capsule was observed as well as phagocytosis of its material. A possible analogy between normal phagocytosis of small-sized bodies and the ring structure obtained when large bodies are involved is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00224692
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  • 105
    Digitale Medien
    Digitale Medien
    Involution of the caudal musculature during metamorphosis in the ascidian, Botryllus schlosseri (1974)
    Springer
    Cell & tissue research 153 (1974), S. 293-305 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Ascidia (Botryllus schlosseri) ; Metamorphosis ; Muscle tissue involution ; Phagocytes ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The caudal musculature of the free-swimming tadpole of the ascidian, B. schlosseri consists of cylindrical mononucleated cells connected in longitudinal rows flanking the axial notochord. During resorption of the larval tail, which is apparently induced by the contraction of the epidermis, muscle cells are dissociated and pushed into the body cavity where most of them are rapidly engulfed by phagocytes. In the initial stages of tail withdrawal muscle cells display surface alterations due to the disruption of intercellular junctions and disarrangement of myofibrils. Extensive degenerative changes, with shrinkage of mitochondria and disintegration of the contractile material are subsequently observed. Lysosomes and autophagic vacuoles are rarely seen and appear to play a secondary role in the degradation of the muscle cells, which occurs predominantly within the phagocytes. Myofilaments and myofibrils have never been observed within autophagic vacuoles. Clumps of muscle fragments and degenerated phagocytes undergo eventual dissolution in the blood lacunae, concomitantly with the differentiation of the young oozooid.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00229160
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  • 106
    Digitale Medien
    Digitale Medien
    Adhesion plaques associated with the production of a daughter cell in Euglypha (Testacea; Potozoa) (1974)
    Springer
    Cell & tissue research 153 (1974), S. 261-268 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Amoebae (Testacea) ; Siliceous plates ; Production ; Role of microtubules in fission ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Euglypha acanthophora and Euglypha strigosa, testate amoebae with siliceous shells, undergo binary fission producing daughter cells. The siliceous plates from which the shells are constructed are produced in the Golgi and perinuclear regions of the parent. At binary fission these pass along microtubule pathways and are manoeuvered into position in the daughter-cell by microtubule (20–25 nm) and microfilament (7–9 nm) systems. The latter in the form of adhesion plaques are instrumental in the coordination and deployment of the shell-plates.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00226614
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  • 107
    Digitale Medien
    Digitale Medien
    Transformations of hypothalamic arcuate neurons (1974)
    Springer
    Cell & tissue research 153 (1974), S. 497-515 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Arcuate nucleus ; Hypothalamus ; Sexual cycle ; Ribbon-rolls ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Changes in subcellular structures of arcuate neurons correlated in a consistent way with stages of the estrous cycle of the rat. Associated with the rough endoplasmic reticulum short ribbons of moderately electron dense material appeared at metestrus and circular or elliptical bodies termed “ribbon-rolls” at diestrus and proestrus. Although present in proestrus, the ribbon-rolls were smaller at this stage. In a few neurons in diestrous females and in ovariectomized animals one to seven months before perfusion multiple large ribbon-rolls occupied much of the cytoplasm. Also, frequency of dense granules and lysosomes increased in diestrus. The significance of the ribbon-rolls and changes in other structures during the estrous cycle are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00231543
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  • 108
    Digitale Medien
    Digitale Medien
    The ventricular system in neuroendocrine mechanisms (1974)
    Springer
    Cell & tissue research 154 (1974), S. 1-16 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Ventricle ; Tanycytes ; Monoamine transport ; Autoradiography ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary This investigation has dealt with a light and electron microscopic autoradiographic analysis of the median eminence of the rat following intraventricular infusion of 3H-dopamine. This study has demonstrated that 3H-dopamine, once infused into the mammalian cerebral ventricular system, is rapidly and selectively absorbed by tanycytes and transported to the contact zone within 5 minutes after ventricular infusion. Certain axon terminals in the ependymal, hypendymal, and palisade-contact zones selectively sequester 3H-dopamine as do subpopulations of arcuate neurons. This picture of intense labelling of neurons and axon terminals is discussed with respect to monoaminergic re-uptake mechanisms. Uptake and transport of 3H-DA by tanycytes is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00221067
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  • 109
    Digitale Medien
    Digitale Medien
    A new membrane organelle in developing amphibian neurones (1974)
    Springer
    Cell & tissue research 154 (1974), S. 103-108 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Plasma membrane specialisations ; Developing neurons ; Xenopus laevis ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Membrane specialisations have been found on neurones in embryos of the clawed toad Xenopus laevis. The specialisations have been called dense membrane knobs and consist of an outpushing of the plasma membrane with a slight increase in its density. The out-pushing forms a spherical knob with an amorphous dense core and a total diameter of 500 to 600 Å. The knobs are found on axons and dendrites both in the spinal cord and peripherally.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00221074
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  • 110
    Digitale Medien
    Digitale Medien
    Gap junctions in the heart of teleost fish (1974)
    Springer
    Cell & tissue research 154 (1974), S. 131-134 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Heart musculature ; Teleost ; Gap junctions ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary An examination of cell contacts was made in the atrial and ventricular muscle of Teleost fish. The intercalated discs consist of two types of junction resembling fascia and macula adherens. Small focal areas of gap junctions were shown to be numerous away from the regions of intercalated disc between the myocardial cells.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00221077
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  • 111
    Digitale Medien
    Digitale Medien
    Ultrastructure of the neurosecretory system of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (1974)
    Springer
    Cell & tissue research 154 (1974), S. 275-288 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Neurosecretion ; Insect ; Leptinotarsa decemlineata ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructure of seven types of neurosecretory cells (NSC) in the medial and lateral groups of the protocerebrum is described. The differences among cell types established earlier by light microscopy parallel differences in size and appearance of the neurosecretory particles observed in electron micrographs. No relationship was found between the affinity for Gomori's paraldehyde fuchsin stain and the nature of the particles. The secretions of the A-, A1-, and C-types of NSC of the medial group are characterized by electron-dense neurosecretory granules of 1250 Å dia., medium-dense granules of 2100 Å, and electron-lucent vesicles of 1700 Å, respectively. The L-type NSCof the lateral group contain smaller (1300 Å) or larger (1700 Å) neurosecretory granules. The medial B- and E-types of NSC and the lateral LB-type contain granulated vesicles (1200 Å) of the same appearance. These cell types differ in other respects and most likely have separate functions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00223726
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  • 112
    Digitale Medien
    Digitale Medien
    Myofibroblasts in the rat testicular capsule (1974)
    Springer
    Cell & tissue research 154 (1974), S. 533-541 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Myofibroblasts ; Testicular capsule (rat) ; Connective tissue ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A specialized type of fibroblast occurs in the testicular capsule of adult rats. The flattened cells are characterized by bundles of cytoplasmic filaments. Filament bundles run parallel to the cell surface and insert in plaques of granular, electron dense material which is attached to the inner surface of the plasma membrane (attachment zones). Cytoplasmic filaments measure 60–80 Å in diameter. Sporadically plaques of basal lamina-like material are found, especially in the region of attachment zones. These specialized fibroblasts are interpreted as myofibroblasts. It is supposed that contractility of the testicular capsule in rats is caused by myofibroblasts.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00219672
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  • 113
    Digitale Medien
    Digitale Medien
    The ultrastructure of the sinus gland of Carcinus maenas (Crustacea: Decapoda) (1974)
    Springer
    Cell & tissue research 155 (1974), S. 117-125 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Sinus gland ; Carcinus maenas (Crustacea, Decapoda) ; Nerve fibre cell types ; Neurosecretion ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The sinus gland of Carcinus maenas consists of the swollen axonal endings of the neurosecretory cells of the major ganglia and acts as a storage release centre for the membrane bound neurosecretory material. These neurosecretory granules fall into five different types based on size and electron density. Their contents are released by exocytosis of the primary granules or smaller units budded from the primary granules.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00220288
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  • 114
    Digitale Medien
    Digitale Medien
    Fine structural and enzyme histochemical observations on the dorsal tail tubercle of Mertensiella caucasica (Urodela, Amphibia) (1974)
    Springer
    Cell & tissue research 156 (1974), S. 103-112 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Dorsal tail tubercle ; Urodela ; Skin ; Hedonic glands ; Electron microscopy ; Enzyme histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Dorsal tubercle and skin of Mertensiella caucasica have been investigated with the electron microscope and enzyme histochemical methods. The epidermis of the tubercle consists of 8–9 cell layers, that of normal dorsal skin of 5–6. The tubercle is filled with large mucous glands which are surrounded by an almost complete layer of smooth muscle cells (myoepithelial cells). Their glandular cells undergo cyclical changes and are characterized by specific secretory granules, which differ from those of the relatively small mucous glands of the normal dorsal skin. In the connective tissue of the tubercle a relatively rich supply of nerve fibres has been found, which in part contain synaptic and dense core vesicles or accumulations of mitochondria. In the normal dorsal skin nerve fibres occur less frequently. The following enzymes have been demonstrated in the mucous glands of the tubercle: SDH, acid phosphatase, unspecific esterases, E 600 resistant esterase. The tubercle seems to stimulate the female cloaca chemically and mechanically.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00220104
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  • 115
    Digitale Medien
    Digitale Medien
    Mode of termination of primary vestibular fibres in the lateral vestibular nucleus an experimental electron microscopical study in the cat (1967)
    Springer
    Experimental brain research 4 (1967), S. 187-211 
    Details
    ISSN: 1432-1106
    Schlagwort(e): Deiters' nucleus ; Electron microscopy ; Primary fibres ; Operated cats
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Following transection of the vestibular nerve in cats, the electron microscopical changes occurring in the lateral vestibular nucleus were studied after survival periods of 2–11 days. Material for study was taken from the rostroventral part of the nucleus of Deiters since this is known to receive the primary vestibular fibres. Degeneration of terminal boutons is evident two days after the lesion. Degenerating boutons show an increased electron optic density, mitochondrial changes and a loss of synaptic vesicles. They are often surrounded by a pericellular space filled with flocculent (probably protein) material. At three days and later this space is occupied by processes of astrocytes or of a type of phagocytic cells which surround or engulf the degenerating boutons. Nine to eleven days after the lesion almost all degenerating boutons have disappeared. There is evidence of phagocytosis of axons and myelin sheaths by astrocytes but mainly by phagocytes of yet undetermined origin. The “filamentous type” of bouton degeneration has not been observed. Degenerating boutons are found on neuronal perikarya and on proximal as well as on thin distal dendrites and on spines. They are common on small and medium-sized cells, but have also been seen on some giant cells. The degenerating boutons do not form series of synaptic complexes. Degenerating fibres and boutons have so far been found only ipsilateral to the lesion. The findings confirm and extend those made in corresponding experiments with silver impregnation procedures, but emphasize the limitations of the latter methods as regards conclusions concerning synaptic contacts.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00248022
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  • 116
    Digitale Medien
    Digitale Medien
    An experimental electron microscopical study on the mode of termination of cerebellar corticovestibular fibres in the cat lateral vestibular nucleus (Deiters' nucleus) (1967)
    Springer
    Experimental brain research 4 (1967), S. 212-236 
    Details
    ISSN: 1432-1106
    Schlagwort(e): Deiters' nucleus ; Electron microscopy ; Purkinje axons ; Operated cats
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The present paper is an experimental study on the mode of termination of cerebellar corticovestibular fibres in the cat. The distribution of degenerating terminal structures as this appears in electron micrographs of eight animals with a survival time from three up to eleven days is described. The early stage of degeneration of Purkinje cell axons is a filamentous reaction during which fibres as well as boutons are enlarged and filled with filaments. The initial reaction is followed by shrinkage, and many fibres and boutons are at the 4 day stage electron dense, and no filaments can be recognized. Other fibres and boutons show intermediate stages of degeneration. Only dark degenerating axons and boutons are present at the 11 day stage. The observations are related to those made in other nuclei and regions where degeneration has been described in electron micrographs. Degenerating terminal myelinated fibres ending with terminal and en passage boutons are found. An attempt is made to correlate the findings with those made in normal animals and in Golgi sections. The mode of termination and the pattern of branching of Purkinje cell axons are discussed. The degenerating terminal structures are in synaptic contact with cells of all sizes and with all parts of the neurons, i. e., soma, proximal and distal dendritic trunks and spine-like projections. Elongated and rounded synaptic vesicles are present in the degenerating boutons. The glial reaction adjacent to degenerating boutons is also described, and brief mentioning is made of findings in the intracerebellar nuclei of the same animals. The findings in these nuclei are essentially the same as those made in the lateral vestibular nucleus.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00248023
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  • 117
    Digitale Medien
    Digitale Medien
    Decrease in the insulin of rabbit pancreas in late pregnancy (1967)
    Springer
    Diabetologia 3 (1967), S. 435-442 
    Details
    ISSN: 1432-0428
    Schlagwort(e): Plasma insulin ; Pancreatic insulin ; Rabbit ; Pregnancy ; A-cells ; B-cells ; Electron microscopy ; Glucagon
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Résumé Le contenu en insuline du plasma de lapins normaux et en gestation a été étudié par rapport à la quantité d'insuline qui pouvait être extraite de leurs pancréas. — Le contenu plasmatique moyen en insuline des lapins normaux, utilisés comme témoins, était de 25μU/ml (entre 18 et 33) et l'insuline extraite de leurs pancréas était de 3.56μg/100 mg de tissu (entre 3.33 et 3.76). — Lorsque la gestation était à un stade avancé, le contenu en insuline dans le sang s'élevait à 56μU/ml (entre 37 et 81), alors que l'insuline extraite du pancréas tombait à 1.17μg/100 mg de tissu (entre 0.65 et 1.73). — L'ultrastructure des cellules A et B pendant la gestation a également été étudiée. La teneur des granules B en insuline diminue et les cellules A présentent des signes évidents d'une haute activité. — Les observations précédentes suggéreraient que lors de la gestation avancée, une synthèse et une sécrétion de glucagon accrues augmentent l'activité sécrétrice du pancréas en insuline.
    Kurzfassung: Zusammenfassung Bei normalen und graviden Kaninchen wurden die Plasma-Insulinspiegel und das aus dem Pancreas extrahierbare Insulin gemessen. — Die mittleren Insulinspiegel der normalen Kontrolltiere lagen bei 25μE/ml (zwischen 18–33), das Pankreasinsulin bei 3.56μg/100 mg Gewebe (3.33–3.76). Die Seruminsulin-spiegel steigen während der späten Schwangerschafts-stadien auf 56μE/ml (37–81) an und das extrahierbare Pancreas-Insulin nimmt auf 1.17μG/100 mg Gewebe (0.65–1.73) ab. — Wir untersuchten die Feinstruktur der Alpha- und Beta-Zellen während der Schwangerschaft: Dabei nahm das in den Beta-Granula gespeicherte Insulin ab und die Alpha-Zellen zeigten eindeutige Zeichen gesteigerter Aktivität. Die oben skizzierten Befunde könnten daraufhin deuten, daß während der späten Schwanger-schaftsstadien eine gesteigerte Glucagon-Synthese und Sekretion die insulinsekretorische Aktivität der Bauchspeicheldrüse erhöht.
    Notizen: Summary Plasma insulin levels and extractable insulin of the pancreas of normal and pregnant rabbits have been studied. — The mean plasma insulin of non-pregnant controls was 25μU/ml (range 18 to 33); extractable pancreas insulin was 3.56μg/100 mg tissue (3.33 to 3.76). — The insulin level in the blood increases during late pregnancy to 56μU/ml (range 37 to 81) and the extractable pancreatic insulin decreases to 1.17μg/100 mg tissue (0.65 to 1.73). — The fine structure of B and A-cells has been studied in pregnancy: insulin stored in B granules decreases and the A-cells show definite signs of increased activity. — The above findings might be interpreted as suggesting that in late pregnancy an increased synthesis and secretion of glucagon augment the insulin secretory activity of the pancreas.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01228079
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