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  • Histochemistry  (18)
  • Mouse  (11)
  • Springer  (29)
  • American Geophysical Union
  • Irkutsk : Ross. Akad. Nauk, Sibirskoe Otd., Inst. Zemnoj Kory
  • Krefeld : Geologischer Dienst Nordhein-Westfalen
  • Wiley
  • 2015-2019
  • 2005-2009
  • 1975-1979
  • 1970-1974  (29)
  • 1973  (29)
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Verlag/Herausgeber
  • Springer  (29)
  • American Geophysical Union
  • Irkutsk : Ross. Akad. Nauk, Sibirskoe Otd., Inst. Zemnoj Kory
  • Krefeld : Geologischer Dienst Nordhein-Westfalen
  • Wiley
Erscheinungszeitraum
  • 2015-2019
  • 2005-2009
  • 1975-1979
  • 1970-1974  (29)
Jahr
  • 1
    ISSN: 1432-0827
    Schlagwort(e): Osteopetrosis ; Diphosphonates ; Bone Resorption ; Mouse ; Calcium ; Tooth ; Bone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Beschreibung / Inhaltsverzeichnis: Résumé L'effet de doses quotidiennes, administrées depuis la naissance, de deux types de diphosphonates, à savoir l'éthane-1-hydroxyle-1,1-diphosphonate (EHDP) et le dichlorométhylène diphosphonate (Cl2MDP), sur la croissance et le squelette de souris a été étudié. Les diphosphonates freinent la croissance: les incisives ne font pas leur éruption ou elle est plus tardive. La calcémie est normale. L'administration de Cl2MDP à une dose quotidienne de 10 mg P/kg/jour provoque des modifications squelettiques identiques à celles des souris grises létales atteintes d'ostéopétrose et les animaux meurent après quatre semaines de traitement. Par rapport aux témoins, les souris traitées présentent des os plus étroits, plus denses et plus déformés: les cavités médullaires sont comblées avec de l'os calcifié et du cartilage. La quantité totale de calcium d'un animal n'est pas augmentée par traitement au diphosphonate, par rapport à un témoin de même âge. Chez les souris grises létales et celles traitées aux diphosphonates, la plupart des anomalies est secondaire à une résorption osseuse diminuée. Ces résultats sont commentés en fonction de l'emploi des diphosphonates au cours de remaniements osseux pathologiques augmentés et en fonction du rôle de la résorption osseuse dans le maintien de la calcémie.
    Kurzfassung: Zusammenfassung Mäuse erhielten von der Geburt an tägliche Dosen folgender zwei Diphosphonate: entweder Äthan-1-Hydroxy-1,1-Diphosphonat (EHDP) oder Dichloromethylen-Diphosphonat (Cl2MDP). Es wurde deren Wirkung auf das Wachstum und das Skelet untersucht. Die Diphosphonate verlangsamten das Wachstum, die Schneidezähne brachen nicht oder erst später durch, aber die Höhe des Plasmacalciums blieb normal. Die Verabreichung von Cl2MDP in Dosen von 10 mg P/kg/Tag führt zu Skeletveränderungen, welche denjenigen der „grey-lethal” osteopetrotischen Mäuse gleichen. Die Tiere sterben nach einer Behandlungsdauer von etwa 4 Wochen. Verglichen mit normalen Mäusen von ungefähr gleichem Alter hatten die behandelten Mäuse kleinere, dichtere und mehr keulenförmige Knochen, und die Markhöhlen waren gefüllt mit verkalktem Knochen oder Knorpel. Die Gesamtcalciummenge im Skelet wurde durch die Diphosphonatbehandlung nicht erhöht; dies ergab sich aus einem Vergleich mit der bei normalen Mäusen desselben Alters gefundenen Menge. Es wird vorgeschlagen, daß bei den „grey-lethal” und bei den Diphosphonat-behandelten Mäusen viele der Abnormalitäten als Folge der herabgesetzten Knochenresorption angesehen werden müssen. Die Ergebnisse werden einerseits im Hinblick auf den Gebrauch der Diphosphonate bei pathologischen Bedingungen eines erhöhten Knochenumbaus diskutiert; andererseits werden sie im Zusammenhang mit der Rolle der Knochenresorption bei der Erhaltung des Plasmacalcium-Spiegels besprochen.
    Notizen: Abstract The effect of daily doses from birth of two diphosphonates, namely either ethane-1-hydroxy-1,1-diphosphonate (EHDP) or dichloromethylene diphosphonate (Cl2MDP), on the growth and the skeleton of mice has been studied. Diphosphonates slowed growth, the incisors did not erupt or erupted later, but the level of plasma calcium remained normal. The administration of Cl2MDP at a dose rate of 10 mg P/kg/day leads to skeletal changes that are similar to those observed in grey-lethal osteopetrotic mice, and the animals die after about four weeks of treatment. As compared with normal mice of similar age, treated mice had bones that were smaller, denser and more clubshaped, and the marrow cavities were filled with calcified bone or cartilage. The total amount of calcium in the carcass was not increased by diphosphonate treatment, as compared with the amount in normal mice of the same age. It is suggested that both in the grey-lethal and diphosphonate-treated mice many of the abnormalities are secondary to decreased bone resorption. The results are discussed with respect to the use of diphosphonates in pathological conditions of increased bone turnover and with respect to the role of bone resorption in the maintenance of plasma calcium levels.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 12 (1973), S. 117-124 
    ISSN: 1432-0827
    Schlagwort(e): Mouse ; Calcification ; Metals ; Mast Cells
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Beschreibung / Inhaltsverzeichnis: Résumé Des souris, ayant reçu par voie intra-veineuse une solution d'acétate de plomb, sont injectés par voie sous-cutanée avec du sulfate de polymixine B. Au niveau de ce dernier point d'injection, on observe des calcifications. L'examen histologique montre une dégranulation des mastocytes, une vaso-dilatation locale ainsi qu'une diffusion d'ions à partir des vaisseaux. Après 24 heures, des ions calcium et phosphate sont présents. En outre. des groupes de souris, pré-injectées par voie intraveineuse avec de l'acétate de plomb, reçoivent des extraits de granules de mastocytes, comportant du phosphate d'histamine, du sulfate de créatinine sérotonine, de l'héparine, du sulfate de chondroitine ou de l'acide hyaluronique. Seules les injections de sérotonine et d'histamine, connues comme vaso-dilatateurs et augmentant probablement la perméabilité capillaire, provoquent des calcifications. Il semble que le rôle des mastocytes dans la calcification soit lié principalement à la production d'une vasodilatation locale, avec perméabilité capillaire augmentée, plutot qu'à une action de liaison initiale des ions métalliques.
    Kurzfassung: Zusammenfassung Nachdem Mäusen Bleiacetatlösungen intravenös eingespritzt worden waren, erhielten die Tiere Polymixin-B-Sulfat subkutan. Dies führte zu Verkalkung an der zweiten Injektionsstelle. Die histologische Untersuchung zeigte eine deutliche degranulation der Mastzellen, eine lokale Vasodilatation und das Austreten von Bleiionen aus diesen Gefäßen 24 Std nach der Injektion konnte eine groß Menge von Calcium- und Phosphationen eindeutig nachgewiesen werden. Weiter wurden Gruppen von Mäusen, die vorher Bleiacetat intravenös erhalten hatten. Bestandteile von Mastzellen-Granula injiziert. Diese bestanden aus Histaminphosphat, Serotonin-Creatinin-Sulfat, Heparin, Chondroitin-Sulfat oder Hyaluronsäure. Unter diesen exogenen Bestandteilen bewirkten nur Serotonin und Histamin eine Verkalkung. Beide sind starke Vasodilatatoren und erhöhen vermutlich die kapillare Permeabilität. Es wird postuliert, daß die Rolle der Mastzelle in der “calcergy” viel eher auf einer lokalen Vasodilatation mit erhöhter kapillarer Permeabilität als auf einer primären Bindung der Metallionen beruht.
    Notizen: Abstract Mice previously injected intravenously with lead acetate solution were injected subcutaneously with Polymixin B Sulphate. This resulted in calcification at the latter injection site. Histological evidence showed marked mast cell degranulation, local vasodilation and the efflux of lead ions from these vessels. At twenty four hours after injection abundant calcium and phosphate ions were readily demonstrated. In addition, groups of mice pre-injected intravenously with lead acetate, were injected with constituents of mast cell granules. These included histamine phosphate, serotonin creatinine sulphate, heparin, chondroitin sulphate or hyaluronic acid. Of these exogenous constituents used, calcification was found only after serotonin and histamine injections, both of which are potent vasodilators and presumbly increase capillary permeability. It is postulated that the role of the mast cell in calcergy may be mainly that of producing local vasodilation with increased capillary permeability rather than the initial binding of metallic ions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Calcified tissue international 12 (1973), S. 169-173 
    ISSN: 1432-0827
    Schlagwort(e): Calcification ; Histochemistry ; Autoradiography ; Fetal ; Mandible
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Physik
    Beschreibung / Inhaltsverzeichnis: Résumé Des rats femelles reçoivent du45Ca ou du32P au 13ème et 18ème jour de la grossesse. Les coupes sériées des têtes de foetus sont étudiées par autoradiographie et par diverses méthodes histologiques pour déterminer la calcification. La détection la plus précoce de45Ca s'observe simultanément comme une réaction positive pour le calcium avec une des méthodes histologiques utilisées.32P est en évidence par les méthodes autoradiographiques un peu plus tard que le45Ca et sa présence coincide avec la réaction positive la plus précoce observée avec les autres méthodes histologiques utilisées. Les os de ces têtes foetales commencent à se calcifier selon un mode particulier commençant par la mandibule, puis l'os frontal et le maxillaire supérieur, suivis par les os nasaux, pariétaux et interpariétaux.
    Kurzfassung: Zusammenfassung Weibliche Ratten erhielten45Ca und32P zwischen dem 13.–18. Tag der Schwangerschaft. Zur Ermittlung der Verkalkung wurden Serienschnitte der Köpfe ihrer Feten mittels Autoradiographie sowie durch verschiedene histologische Methoden untersucht. Das erste Auftreten von45Ca war ebenfalls von einer positiven Calciumreaktion mittels einer der verwendeten histologischen Methoden begleitet.32P wurde in der Autoradiographie erst etwas später als45Ca festgestellt und dessen Nachweis deckte sich mit den ersten positiven Reaktonen aller anderen verwendeten histologischen Methoden. Die Knochen in diesen Fetusköpfen begannen in einer bestimmten Sequenz zu verkalken: zuerst der Unterkiefer, dann das Stirnbein und der Oberkiefer, dann das Nasenbein, die Parietal- und Interparietalknochen.
    Notizen: Abstract Female rats were given45Ca or32P from 13 to 18 days of pegnancy. Serial sections from the heads of their fetuses were studied by autoradiography, as well as by several histological methods for assessing calcification. The earliest detection of45calcium occured at the same time as a positive reaction for calcium with one of the histological methods used.32P was not detectable by autoradiographic methods until somewhat later than45Ca, and its presence coincided with the earliest positive reaction with all of the other histological methods employed. The bones in these fetal heads began to calcify in a partcular sequence, the mandible first, then the frontal bone and maxilla, followed by the nasal, parietal and interparietal bones.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 136 (1973), S. 85-96 
    ISSN: 1432-0878
    Schlagwort(e): Liver ; Lampetra ; Physiological biliary atresia ; Electron microscopy ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A morphologic and histochemical study was carried out on the liver of larval and adult lampreys at the optical and electron microscopic level. In the larva the liver is composed of blind ending single cell thick tubules of hepatocytes. The tubular lumina provided with microvilli are morphologically comparable with the canalicular lumens of the higher species of animals. The cytoplasm of the hepatocytes contains numerous inclusions with heterogeneous appearance and crystalline material. The biliary system is composed of numerous bile ductules and ducts. In the adult lamprey, the biliary system has disappeared. The hepatocytes loose their tubular arrangement and the characteristic differentiation of their biliary pole. In contrast to previous reports in the literature the presence of bile pigment in the adult lamprey liver could not be demonstrated with any histochemical technique.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 5
    ISSN: 1432-0878
    Schlagwort(e): Locus coeruleus (Rat) ; Neurons ; Golgi apparatus ; Catecholamine biosynthesis ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Detailed histochemical studies have been performed on the morphology of the Golgi apparatus (GA) by application of the thiamine pyrophosphatase (TPPase) method (Novikoff and Goldfischer, 1961) to the neurons of the locus coeruleus (LC) of normal and catecholamine biosynthesis inhibitors (fusaric acid and D, L-α-methyl-p-tyrosine methylester HCl) given adult healthy male Wistar strain rats. The neurons were classified into five categories on the basis of the morphology of the Golgi apparatus. The number of cells in individual categories was counted to evaluate the percentage of each category in the whole nucleus. The majority of cells belongs to Types II, III, and IV whose GA goes through cyclic activity, but the remaining neurons belong to Types I and V which may have a strong tendency to be different from the former in character. The latter neurons correspond formally with Types I and V of the rabbit LC, but they do not respond to the drugs administered. The rat LC is very similar to the dorsal vagal nucleus of the rabbit in regard to the dominant category. The present results indicate that the majority of the rat LC neurons may work vigorously and they may be motor neurons. Administration of the drugs caused reduction of TPPase activity, augmentation of disintegration and the budding-off process of the GA of Type IV, a decrease in the percentage of Type IV and an increase in that of Type II. Administration of 100 mg/kg fusaric acid caused maximal morphological change of the GA at the 90th minute; however, administration of 200 mg/kg fusaric acid showed more marked change of the GA, having two peaks and two valleys. The GA revealed much more intense reaction to D,L-α-methyl-p-tyrosine methylester HCl than to fusaric acid. The present results indicate that tyrosine hydroxylase may be the rate-limiting enzyme in the catecholamine biosynthesis. These noticeable changes of GA caused by administration of the drugs were completely restricted to the neurons of LC and the neurons of the mesencephalic nucleus of the trigeminal nerve did not show any morphological changes of the GA. These results strongly suggest that the GA of the rat LC neurons may have ability to synthesize catecholamine whereas the GA of the rat mesencephalic nucleus of the trigeminal nerve may be completely devoid of this ability and that the role of the GA may be different depending on the anatomical regions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 139 (1973), S. 463-471 
    ISSN: 1432-0878
    Schlagwort(e): Gallbladder (Human) ; Mucus secretion ; Reverse pinocytosis ; Histochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Mucous secretory activity of the human gallbladder epithelium was investigated by light and electron microscopy and with histochemical techniques. There are two types of granules in the supranuclear region of the epithelial cells. The one low in density contains a fine filamentous material and gives a strongly positive silver methenamine reaction. The other is dense and only faintly positive. The granules of the former are considered to be mucous secretory granules and the granules of the latter may be lysosomes. PAS positive granules correspond presumably to both types of granules mentioned above. The mucous secretory granules are considered to be synthesized by the Golgi apparatus and the granular endoplasmic reticulum as has been confirmed in other mucous secretory cells. Their content is released from the cell by reverse pinocytosis. Typical goblet cells occur frequently in the fetal epithelium, but cannot be observed in the adult specimens.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 7
    ISSN: 1432-0878
    Schlagwort(e): Hippocampal region (rat) ; Distribution of dehydrogenases ; Postnatal development ; Histochemistry ; Light microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Succinate-, α-glycerophosphate-, NADH-, and NADPH dehydrogenases (tetrazolium reductases) were studied histochemically in brain sections. The distribution of these enzymes in the hippocampal region was mapped in different postnatal stages. In addition to the hippocampus and the dentate area which have also been dealt with by other authors, the description includes the entorhinal area, parasubiculum, presubiculum, and subiculum. In all the areas of the hippocampal region the enzyme activity is first localized mainly in cell bodies. Activity in the neuropil shows a tendency to increase with age throughout the stages studied. Examples of particularly early or late differentiation of the histochemical pattern exist. Thus already after 4–6 days the differentiated staining pattern in the hippocampal layers as seen in the adult, begins to appear. In the entorhinal area the early enzyme distribution agrees with that in the adult and facilitates identification of its layers. After 22 days the fundamental enzyme chemoarchitectonics of the adult rat brain has been obtained. Histochemical characteristics of the different areas, support the view that the hippocampal region constitutes an entity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 141 (1973), S. 375-400 
    ISSN: 1432-0878
    Schlagwort(e): Hippocampal region (rat) ; AChE distribution ; Postnatal development ; Histochemistry ; Light microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Acetylcholinesterase (AChE) in the hippocampal region was studied histochemically in different postnatal stages. Enzyme changes are described for the hippocampus proper, the dentate area, the entorhinal area, parasubiculum, area retrosplenialis e, presubiculum, and subiculum. In 1 day old animals there are only traces of AChE in solitary perikarya of the hippocampal stratum radiatum, while there is no activity in the neuropil. This is in contrast to other regions of the brain, e.g. the corpus striatum and the medial septum. Enzyme activity in the neuropil, although very weak, is seen clearly on the 2nd day. While the enzyme reaction in some cell soma seems to be permanent and also present in adult rats, other cell bodies, e.g. in the entorhinal area lose AChE activity during the last part of the 2nd week and in the 3rd week. Similar observations have been made on other parts of the central nervous system. The main features of chemodifferentiation in the hippocampal region seem to be completed by the end of the third week, although most layers and areas have not yet achieved the same high staining intensity as seen in the adult rats.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 141 (1973), S. 529-544 
    ISSN: 1432-0878
    Schlagwort(e): Osteoclast ; Parathyroid hormone ; Lysosomes ; Bone resorption ; Electron microscopy ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Young rats were treated with high doses of parathyroid hormone (PTH). Osteoclasts from these animals revealed characteristic alterations in comparison to control cells: a) The cytoplasm contained large vacuoles with phagocytosed cells, some of which resembled osteoblasts or osteocytes. The vacuoles were interpreted as lysosomes because the engulfed cells often appeared partly digested and the vacuoles contained acid phosphatase as demonstrated histochemically, b) lipid droplets were present in the cytoplasm and usually located close to the endoplasmic reticulum and/or in regions with many free ribosomes, c) the Golgi complex was more frequently separated from the nuclei than in control cells, d) small coated cytoplasmic bodies were numerous in the peripheral cytoplasm, e) the membranes of the endoplasmic reticulum were fused in some places, f) cytoplasmic regions with numerous free ribosomes were frequent, g) large ring-shaped granules occurred in some mitochondria. Energy dispersive X-ray analysis of these granules provided evidence that they contained calcium and probably phosphorus, h) in some osteoclasts the mitochondria were enlarged. — The findings are consistent with an increased activity of osteoclasts and in particular a stimulation of the lysosomal system in these cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 138 (1973), S. 155-169 
    ISSN: 1432-0878
    Schlagwort(e): Spermiogenesis ; Mouse ; Multinucleate spermatids ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary This ultrastructural study confirms and extends the light microscope findings of Bryan (1971) concerning the presence and developmental fate of multinucleate spermatids. Four main classes of cells: uninucleate-individual, uninucleate-conjoined, multinucleate-conjoined, and multinucleate-individual, were identified along with a few instances of more complex syncytial organizations. When the respective nuclei in a given multinucleate are far enough apart, each develops autonomously but in synchrony with its neighbors. When nuclei are intimately associated, the “normal” pattern of spermiogenesis may be altered, giving rise to highly bizarre spermatozoa. Commonly, a single Golgi complex serves a pair of nuclei and gives rise to a “T-shaped” acrosome which binds the nuclei together. During the ensuing nuclear elongation phase, such units are invested by a single manchette. Pairs of axonemes within a common plasma membrane have also been encountered. These ultrastructural findings indicate that multinucleate spermatids are true components (not artifacts) of the seminiferous epithelium of normal animals. The presence of such cells and the unusual developmental consequences which can arise as a result of the multinucleate state must be taken into account when evaluating the course of spermatogenesis in cases of mutation- or chemically-induced infertility.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 11
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 136 (1973), S. 263-275 
    ISSN: 1432-0878
    Schlagwort(e): Vaginal epithelium ; Cell differentiation ; Mouse ; Estradiol sensitive antigen ; Immunocytology, Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The distribution of an antigenic material specific for the cervicovaginal epithelium (CVA) was studied in the vaginal epithelium of the adult mouse with immunofluorescence and immunoferritin techniques. The antigen localization has been correlated to the fine structure of the vaginal epithelium in various states of functional activity. The antigen distribution in adult ovariectomized mice and in ovariectomized mice treated with estradiol was compared with that in normal cycling mice. CVA was found to be associated with the exterior of the cell membrane of vaginal epithelium cells, being part of the glycocalyx. Two cell types, mucous or keratinized, are derived from the germinative cell layer of the vaginal epithelium, depending on the hormonal environment. Mucous cells with morphological features that characterize cells about to cornify have been demonstrated. Fluorescence as well as ferritin particles, indicating the presence of antigen-antibody complexes, were seen within the mucous droplets of the mucous cells. The CVA production is apparently connected with vaginal mucus formation. The CVA distribution in the adult vaginal epithelium is discussed in relation to the distribution demonstrated earlier in the cervicovaginal epithelium of neonatal mice.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 12
    ISSN: 1432-0878
    Schlagwort(e): Ovary (mouse) ; Granulosa cells ; Steroidogenesis ; Electron microscopy ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A systematic study of Δ5-3β-hydroxysteroid dehydrogenase in the granulosa cells of immature and mature mice was made. The histochemical results were compared with the ultrastructural findings on the same cells in an attempt to determine whether the granulosa cells are capable of a steroidogenic role. In newborn and immature mice the granulosa cells of a great amount of follicles demonstrated a moderate or strong histochemical activity. In mature mice the granulosa cells demonstrated a weak or moderate activity normally only in preovulatory follicles and in some other atretic follicles. The granulosa cells of the normal developing follicles did not show such activity. In addition the histological control of numerous parallel sections demonstrated particularly in immature ovaries the presence of a great amount of atretic follicles. In the cytoplasm of the granulosa cells of the follicles in immature ovaries only clusters of lipid droplets with ribosomes were noted; while in the preovulatory follicles of mature animals there started to appear mitochondria with tubular cristae, smooth membranes of the endoplasmic reticulum and irregular lipid droplets. In the obviously atretic follicles several granulosa cells as well as theca interna cells showed numerous lipid droplets and ribosomes together with different degenerating organelles. The granulosa cells of the normal developing follicles showed a well developed Golgi complex, granular endoplasmic reticulum and free ribosomes. The histochemical and ultrastructural findings suggest a steroidogenic role of the granulosa cells only in the larger preovulatory follicles (probably related to an early luteinization of this layer) but this role was not demonstrated in the same cells in normal developing follicles. In addition, since an histochemical positivity was demonstrated also in the granulosa cells of some obviously atretic follicles, it is possible that many of the follicles having granulosa cells filled with lipid droplets and attached ribosomes and histochemically positive might be, in the immature ovaries, in a very precocious stage of atresia. It is to precise for these cells whether a cytoplasm with these two strictly correlated components (lipid droplets and attached ribosomes) and showing an histochemical positivity could carry-on all the biochemical steps involved in steroid biosynthesis or only has only a temporary capability to produce some precursors of steroids.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 13
    ISSN: 1432-0878
    Schlagwort(e): Reproductive tract ; Biomphalaria glabrata ; Desiccation ; Starvation metabolism ; Weighing experiments ; Histochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The effects of desiccation (36 weeks), starvation (12 weeks) and recovery (4 weeks following 16 weeks of desiccation and 2 weeks following 9 weeks of starvation) upon the accessory sex glands and some other body parts of Biomphalaria glabrata were studied by means of weighing experiments and histochemical and ultrastructural methods. The results of the weighing experiments show that the various parts of the reproductive tract are not protected from involution processes during the adverse conditions, as some parts (the albumen gland, spermduct and prostate gland) showed a more pronounced decrease in weight than other body parts. Measurements of the epithelial heights of the accessory sex glands and ultrastructural observations corroborate the results of the weighing experiments. During the adverse conditions the organelles involved in the formation of the secretion granules (granular endoplasmic reticulum and Golgi-apparatus) became involuted. The secretion granules within the cells of the albumen gland, spermduct and prostate gland were broken down by crinophagy. This latter process was less pronounced in the oviduct, muciparous gland, oöthecal gland, uterus and vagina. During the adverse conditions the lipoprotein producing cell types (mainly in the male part) remained active longer than the polysaccharide producing cell types (mainly in the female part). The significance of this observation is discussed. The amounts of glycogen present in most tissues of the reproductive tract and of the other investigated body parts (the foot, columellar muscle and vesicular connective tissue cells) were not apparently diminished, even when the secretory cells showed clear signs of involution, as a result of long periods of adverse conditions. Within the recovery periods 50% of the snails resumed egg production. During recovery the relative increases in weight of the accessory sex glands seemed to exceed that of other body parts, indicating that the restoration of the accessory sex glands is favoured. Histologically, reactivation of the accessory sex glands was apparent after 36–72 hours of recovery. At this time secretory material was again observed within the cisternae of the gland cell Golgi-bodies. Because reactivation is fairly rapid, a nervous or hormonal control of this process appears more likely than control via the general metabolism. The possible functions of various body organs in storing food reserve material is discussed, and it is concluded that the glycogen storing vesicular connective tissue cells (which occur throughout the whole body in the connective tissue) play a major role.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 14
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 146 (1973), S. 319-328 
    ISSN: 1432-0878
    Schlagwort(e): Hypothalamus ; Mouse ; Arcuate neurons ; Nucleolus-like bodies ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The arcuate nucleus of untreated (control) and castrated adult mice was studied with the electron microscope. Nucleolus-like bodies (NLB) were found in the cytoplasm and occasionally in the dendrites of arcuate neurons. NLB were spherical or ovoid, 0.7–1.5µm in diameter; they were composed of granules 100–150 Å and 200 Å in diameter, and filaments ∼70 Å in diameter. NLB were frequently associated with free ribosomes and cisternae of the rough endoplasmic reticulum. Light microscopic studies with basic dyes and enzymatic digestions showed that these bodies contained some RNA. There was no significant change in the number of NLB in castrated animals.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 15
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 144 (1973), S. 339-351 
    ISSN: 1432-0878
    Schlagwort(e): Nervous system ; Tissue culture ; Sheath cells ; Sensory end-organs ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Fetal spinal ganglia and spinal cord segments with adhering spinal ganglia were explanted on collagen-coated coverslips. They were investigated with enzyme histochemical methods for the existence of hydrolases and dehydrogenases up to 54 days of cultivation. Alkaline phosphatase was located in arachnoid cells and in mantle cells (satellite cells). Butyrylcholinesterase and alpha-glycerophosphate-menadione-tetrazolium reductase were found in mantle cells. Acetylcholinesterase and indoxylesterase were active in the whole neuron; acid phosphatase and alpha-naphthylacetate esterase were restricted to the perikarya. During the process of cell differentiation in vitro alkaline phosphatase decreased in mantle cells. Acid phosphatase became diminished distinctly in spinal ganglion cells. The other neuronal enzymatic activities remained unaltered during the whole period of cultivation. Proliferated Schwann cells were conspicuous by their activity for butyrylcholinesterase. In newly formed myelin sheaths arylsulphatase was active. Lactate dehydrogenase was contained in the perineurium which had developed. Cultures of long duration could contain cytological formations which were reminiscent of sensory end-organs with respect to their enzyme patterns. The enzyme activities of nervous tissues in vitro in their approximation to the situation in situ are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 16
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 140 (1973), S. 445-449 
    ISSN: 1432-0878
    Schlagwort(e): Cecum, Colon ; Mouse ; Glycocalyx ; Intestinal microorganisms ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructure of the cecal epithelium of the mouse resembles that of more distal parts of the colon. A brief discussion is presented of the possible significance of apical cytoplasmic granules to the glycocalyx and of the close association of microorganisms with the lining epithelium.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 17
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 142 (1973), S. 465-477 
    ISSN: 1432-0878
    Schlagwort(e): Rabbit thymus ; Ketosteroids ; Granulated cells ; Histochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Topochemisch konnten im Kaninchenthymus Ketosteroide nachgewiesen werden, für deren Vorhandensein die chemische Analyse von Thymuslipidextrakten Hinweise ergeben hatte. Die Darstellung der Ketosteroide erfolgte mit der NAHD-Reaktion (Camber, 1949). Diese Befunde dürften als spezifisch gelten, da eine Verfälschung durch freie Gewebsaldehyde, Plasmalogene (Gomori, 1952) und Corticosteroide (Khanolkar et al., 1958) ausgeschlossen wurde. Mit Hilfe der Camber-Methode konnten Granula bestimmter Zellen des Kaninchenthymus selektiv dargestellt werden, die auf Grund morphologischer Kriterien in zwei Gruppen unterteilt wurden. Die Zellen liegen im gesamten Thymusparenchym sowie im Bindegewebe der Septen und der sogenannten „Kapsel“. Prädilektionsorte stellen die Umgebung der Hassallschen Körperchen, die Mark-Rinden-Grenze, der intra- und perivasale Raum sowie die subkapsuläre Zone dar. Beide Zellgruppen sind Sudan III-, PAS- und Eosin-positiv, besitzen eine ausgeprägte gelbgrüne Eigenfluoreszenz und können differentialdiagnostisch gegen Mastzellen abgegrenzt werden. Elektronenmikroskopisch zeigen beide Zellgruppen zahlreiche Übereinstimmungen mit Reifestadien eosinophiler Knochenmarkszellen.
    Notizen: Summary Ketosteroids were demonstrated topochemically in the rabbit thymus following indications given by chemical analysis of thymus lipid extracts. They were revealed by means of the NAHD-reaction (Camber, 1949). The results are thought to be specific, because adulteration by free tissue aldehydes, plasmalogens (Gomori, 1952) and corticosteroids (Khanolkar et al., 1958) can be excluded. The Camber-method selectively reveals the presence of two groups of morphologically differentiable granules in specific rabbit thymus cells which are distributed throughout the entire thymic parenchyme as well as in the connective tissue of the septa and the in so-called “capsule”. They are mainly seen in the vicinity of Hassall's bodies, in the zone between medulla and cortex, the intra- and perivascular space and in the subcapsular space. Both cell groups are Sudan III-, PAS- and eosin-positive, show intensive yellow-green primary fluorescence and can be distinguished from mast cells by differential diagnosis. Electron microscopy reveals that both cell groups show many similarities with the maturation phase of bone marrow eosinophils.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 18
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 145 (1973), S. 389-416 
    ISSN: 1432-0878
    Schlagwort(e): Adrenal chromaffin cells ; Ganglion cells ; Avian adrenal gland ; Light- and electron microscopy ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The fine structure of the adrenal gland of 15 bird species was investigated by light-, fluorescence-, and electron microscopy as well as by histochemical methods. 1. Adrenal Chromaffin Cells. Cells producing adrenaline (A) and noradrenaline (NA) may be distinguished from each other with the electron microscope by the different structure of their granules. In all species investigated A-cells prevailed. Granules in A-cells of Corvidae, partly those of the other passeriform birds as well, resemble granules from the pituitary pars intermedia because of their incomplete membrane and the low electron density of their contents. A-cells of some passeriform birds have mitochondria with specifically arranged cristae. Large cytosomes and inclusions of lipofuscin pigment are to be found in the gulls Larus ridibundus and Larus argentatus. The House Sparrow (Passer domesticus) and the Chaffinch (Fringilla coelebs) show vacuoles filled with a colloid-like substance, which are surrounded by adrenal chromaffin cells. 2. Ganglion Cells. The adrenal gland of birds is rich in ganglion cells. Two types can be distinguished. “Large” ganglion cells resemble completely sympathetic nerve cells as described in many vertebrates. “Small” ganglion cells have a low nucleus-cytoplasm-ratio. Some of them include granules of various structure and quantity. Whether they represent transitional stages to adrenal cells, interneurons, P-neurons or a heterogeneous population remains to be clarified.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 19
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 145 (1973), S. 417-442 
    ISSN: 1432-0878
    Schlagwort(e): Adrenal chromaffin cells ; Birds ; Cholinergic innervation ; Histochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary According to their ultrastructure and histochemistry three types of efferent nerve fibers can be distinguished in the bird's adrenal gland. The main part is made up of cholinergic fibers recognizable by a positive reaction for acetylcholinesterase and two specific populations of granules within the synaptic ending. Synaptic vesicles measuring 300 to 500 Å in diameter and dense-cored vesicles with a diameter of about 1 000 Å are discernible. In the periphery of the gland cholinergic axons for the innervation of adrenal cells form large bundles surrounded by a perineural sheath. The bundles cross the capsule and are situated within the adrenal chromaffin cords or at their periphery. Finally small groups of fibers enter a group of chromaffin cells which are surrounded by a basal lamina and which consist of about a dozen or more cells producing adrenaline and noradrenaline. Synaptic endings occur, above all in passeriform species, in the center of a chromaffin cell complex. They are either attached to the innervated cells or their dendrite-like processes, or embedded into the cells, or connected to short spines of the innervated cells. Synaptic and dense-cored vesicles leave the bouton by exocytosis. One synaptic terminal may innervate up to three A- or NA-cells. The existence of different types of synapses for A- and NA-cells cannot be excluded.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 20
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 139 (1973), S. 201-215 
    ISSN: 1432-0878
    Schlagwort(e): Median eminence ; Mouse ; Ontogenesis ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Beschreibung / Inhaltsverzeichnis: Résumé Les fibres nerveuses renfermant des vésicules granuleuses et des vésicules de type synaptique apparaissent dans l'éminence médiane de foetus de 14 jours. Dés le 18è jour foetal, de véritables terminaisons nerveuses sont au contact des capillaires du plexus intercalaire, constituant une charnière neurohémale. Les anses intrainfundibulaires commencent à pénétrer dans l'éminence médiane à la naissance mais ce n'est que chez des souris de 5 jours qu'elles deviennent très nombreuses. — Nous discuterons sur des critères morphologiques, de la possibilité d'un contrôle hypothalamique sur l'adénohypophyse avant la naissance.
    Notizen: Summary Nerve fibers containing granular vesicles and vesicles closely resembling synaptic vesicles appear in the median eminence of 14 days old mouse fetuses. At 18th fetal day true nerve endings have been observed which are located close to the capillaries of the superficial plexus forming a neurovascular link. The capillary loops penetrate into the median eminence at the time of parturition but only in 5 days old mice they can be observed more frequently. — On the basis of the morphological observations presented the question is discussed whether the hypothalamus can influence pituitary hormone secretion before birth.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 21
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 139 (1973), S. 217-236 
    ISSN: 1432-0878
    Schlagwort(e): Subcommissural organ ; Mouse ; Mucopolysaccharides ; Acid phosphatase activities
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In mice most of the ependymal cells of the subcommissural organ (SCO cells) are densely packed with dilated cisternae of the endoplasmic reticulum (ER) containing either finely granular or flocculent materials. The well developed supra-nuclear Golgi apparatus consists of stacks of flattened saccules and small vesicles; the two or three outer Golgi saccules are moderately dilated and exhibit numerous fenestrations; occasional profiles suggesting the budding of coated vesicles and formation of membrane-bound dense bodies from the ends of the innermost Golgi saccules are seen. A few coated vesicles and membrane-bound dense bodies of various sizes and shapes are also found in the Golgi region. The contents of the dilated ER cisternae are stained with periodic acid-silver methenamine techniques. In the Golgi complex the two or three inner saccules are stained as deeply as the dense bodies, and the outer saccules are only slightly stained. The stained contents of ER cisternae are more electron opaque than those of the outer but less opaque than those of the inner Golgi saccules and the dense bodies. Acid phosphatase activities are localized in the dense bodies, some of the coated vesicles in the Golgi region, and in the one or two inner Golgi saccules. On the basis of these results the following conclusions have been reached: (1) In mouse SCO cells the finely granular and the flocculent materials in the lumen of ER cisternae contain a complex carbohydrate(s) which is secreted into the ventricle to form Reissner's fiber; (2) the secretory substance is assumed to be synthesized by the ER and stored in its cisternae, and the Golgi apparatus might play only a minor role, if any, in the elaboration of the secretory material; (3) most of the dense bodies in the mouse SCO cells are lysosomal in nature instead of being so-called dark secretory granules.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 22
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 139 (1973), S. 253-269 
    ISSN: 1432-0878
    Schlagwort(e): Branchial gland ; Cephalopoda ; Fine structure ; Hemocyanin ; Histochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Licht- und elektronenmikroskopische Untersuchungen an der Branchialdrüse verschiedener Cephalopoden (Sepia officinalis, Octopus vulgaris, Loligo vulgaris, Eledone moschata) zeigen, daß das Drüsengewebe des stark vaskularisierten Organs aus einem sekretorisch aktiven Zelltypus mit ausgeprägtem endoplasmatischen Retikulum besteht. In den Zisternen des endoplasmatischen Retikulums lassen sich granuläre und ringförmige Strukturen (Durchmesser: 45–65 Å und 170 Å) nachweisen, die in Größe und Gestalt mit den Hämocyanin-Einheiten in den Gefäßen und Lakunen übereinstimmen und durch randlichen Zerfall der Zellen in den Blutraum auszuwandern scheinen. Die histochemischen Untersuchungen ergeben eine positive Reaktion für Monoaminoxydase, aber vergleichsweise geringe Phosphatase- und Dehydrogenase-Aktivitäten. Diese Befunde sowie der histochemisch nachgewiesene hohe Kupfergehalt des Drüsengewebes sprechen für eine hämopoetische, d.h. hämocyaninbildende Funktion der Kiemendrüse.
    Notizen: Summary Light and electron microscopic investigations on the branchial gland of different Cephalopoda (Sepia officinalis, Octopus vulgaris, Loligo vulgaris, Eledone moschata) show that the gland tissue, strongly vascularized, consists of an actively secreting cell type with a remarkable endoplasmatic reticulum. In the cisternae of the endoplasmatic reticulum granular and ring-shaped structures can be identified (diameter: 45–65 Å and 170 Å) which correspond in size and shape with the hemocyanin units in the vessels and lacunae and which seem to emigrate into the blood space caused by the peripheral decay of the cells. Histochemical investigations show a positive reaction for monoaminoxidase, but comparatively low phosphatase and dehydrogenase activities. These results, and also the high content of histochemically identified copper in the gland tissue, seem to indicate a hemopoetic, i.e. hemocyanin-forming function for the branchial gland.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 23
    ISSN: 1432-0878
    Schlagwort(e): Brain ; Hypothalamo-hypophysial system ; Xenopus laevis, tadpoles ; Monoamines ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In tadpoles of Xenopus laevis the histochemical distribution of monoamines in the tel-, di- and mesencephalon was studied. Catecholamines are present in some mitral cells of the olfactory bulb, the neurons of the preoptic recess organ (PRO), the neurons of the paraventricular organ (PVO) and cells in the vicinity of the PVO, namely the so-called PVO-accompanying cells, the nucleus infundibularis dorsalis (NID) and in the nucleus reticularis mesencephali (NRM). The PRO, PVO, and NID are composed of liquor-contacting neurons. With the Falck-technique, in the PVO and NID two types of fluorescent cells were observed: green cells, containing a catecholamine and yellow-orange cells, presumably containing a tryptamine. Tryptaminergic neurons occur in the NRM and in the area of the raphe nucleus. Extensive tracts of fluorescent fibres originating in the hindbrain ascend to the area praeoptica and the septum, striatum and epistriatum of the telencephalon. Also, fibre connections could be traced from the PVO to the area praeoptica, to the thalamus and to the nucleus ventromedialis tuberis. The PVO and/or NID give rise to a catecholaminergic tract running towards the hypophysis. Fibres of this tract partly terminate in the developing median eminence and partly in the pars intermedia. Experimental data indicate that the aminergic fibres in the pars intermedia exert an inhibitory influence on MSH-release.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 24
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 137 (1973), S. 167-175 
    ISSN: 1432-0878
    Schlagwort(e): Leydig cells ; Mouse ; Ring-shaped nucleolus ; Endoplasmic reticulum ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Many mature Leydig cells of adult mice contain annular nucleoli. In the cytoplasm of these cells, there is an abundance of agranular endoplasmic reticulum and its modifications, i.e. membranous whorls and double-walled tubules. By contrast, the cytoplasm of Leydig cells with compact nucleoli shows abundant free ribosomes and granular endoplasmic reticulum. It is assumed that the granular endoplasmic reticulum shifts to the agranular endoplasmic reticulum and its modifications during the differentiation of the Leydig cell. For the maturation of the Leydig cell the annular nucleoli may play an important role.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 25
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 137 (1973), S. 159-166 
    ISSN: 1432-0878
    Schlagwort(e): Ovum ; Mouse ; Membranes ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Ultrastructural studies have revealed the presence of unusual membrane complexes within developing mouse oocytes. These structures, most obvious 18 days post fertilization, are found in the nucleus or cytoplasm of cells in meiotic prophase. The complexes, usually found in small groups, are characterized by a slightly bowed appearance, and a thin middle section that is vesiculated at each end. At high magnification the middle section exhibits a pentalaminar structure similar to tight junctional complexes, while the looped membranes of the vesiculated ends are trilaminar in appearance. In addition to being free in the nucleoplasm or cytoplasm, the complexes are also seen in continuity with the inner and outer leaflets of the nuclear envelope, and with typical membranes forming cytoplasmic tubular systems. The possible formation of these complexes from blebs or vesicles derived from the nuclear envelope is presented and the role that these structures may play in developing oocytes is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 26
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 140 (1973), S. 77-89 
    ISSN: 1432-0878
    Schlagwort(e): Intercellular junctions ; Neonatal liver ; Mouse ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Beschreibung / Inhaltsverzeichnis: Résumé Au cours du passage de la vie foetale à la vie postnatale, on note, dans le foie de souris, l'apparition d'associations jonctions-organites cellulaires. Celles-ci cont de deux types: associations desmosomes-organites et associations nexus-organites. 1.Associations nexus-organites. Le long de la «gap junction» sont étroitement accolés, uni ou bilatéralement, divers organites: mitochondrie(s), subsurface cisterna(e), peroxysome(s) ou lysosome. Ces associations n'apparaissent qu'entre le 21ème jour de la gestation et le ler jour post-natal, période à partir de laquelle ils disparaissent au profit d'associations desmosomes-organites cellulaires. Un nouveau type de structure s'associe dans le foie aux membranes plasmatiques: il s'agit des saccules ergastoplasmatiques ou subsurface cisternae. 2.Associations desmosomes-organites. Dans ces complexes, les tonofilaments desmosomiques entrent étroitement en contact avec la paroi des organites cellulaires associés: mitochondrie ou peroxysome. Déjà présents au 13ème jour de la gestation, ces structures s'observent plus fréquemment à partir du ler jour post-natal. La signification de ces associations reste à déterminer, d'autant plus que leur présence a déjà été signalée dans de trés nombreux tissus. Quelques hypothèses sont présentées.
    Notizen: Summary During the transition between the fetal and postnatal periods associations between cell junctions and cell organelles appear in the liver of the mouse. These associations are of two types: desmosome-organelle and nexus-organelle. 1.Nexus-Organelles Association. Unilaterally or bilaterally, various organelles — mitochondria, cysternae, microbodies or lysosomes — adhere tightly along the gap. These associations appear only between the 21st day of gestation and the first postnatal day. Thereafter they gradually disappear and are replaced by desmosome-organelle associations. Another type of structure — ergastoplasmic saccules or cisternae of rough endoplasmic reticulum — become associated with the cell membrane. 2.Desmosome-Organelle Associations. In these complexes the desmosomal microfilaments are in close contact with membranes of the associated organelles — mitochondria or peroxysomes. The associations, which exist as early as the 13th day of gestation increase after the first postnatal day. The significance of these associations remains to be ascertained, especially since they occur in many other tissues. A few hypotheses are presented.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 27
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 140 (1973), S. 91-100 
    ISSN: 1432-0878
    Schlagwort(e): Pulmonary and bronchial vessels ; Laboratory mammals ; Cholinesterase-containing nerve fibres ; Species differences ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Distribution of cholinesterase-containing nerve fibres on blood vessels in the lungs of rats, mice, rabbits, guinea pigs, cats, dogs, and rhesus monkeys has been studied with the thiocholine method modified by Coupland and Holmes and with the “direct-coloring” method according to Karnovsky and Roots. The presence of acetylcholinesterase positive nerve fibres on the pulmonary arteries has been established only in four species of the studied animals, namely the cat, the dog, the rhesus monkey and the rabbit. These nerves form d distinct plexus on the border between the media and adventitia. In the thick walled perihilar branches of the pulmonary artery of the rabbit the nerve fibres penetrate—as a rule—into the outer half of the media. Despite many times repeated experiments and careful investigations no nerve fibres have been found on the intrapulmonary branches of the blood vessels in the lungs of rats, mice, and guinea pigs. In the walls of the pulmonary veins, with the exception of the pulmonary veins in the rat and the mouse, cholinesterase fibres have been identified only seldom. Acetylcholinesterase nerve fibres in medio-adventitial localization have also been found in the walls of bronchial arterioles, this being the case in all the species under study. Bronchial veins do not exhibit any nerve fibres. The distribution of the acetylcholinesterase-containing nerve fibres on the pulmonary arteries is different from species to species.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 28
    ISSN: 1432-0878
    Schlagwort(e): Neurosecretory cells ; Lateral ; Locust ; Histochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Beschreibung / Inhaltsverzeichnis: Résumé L'étude histologique, histochimique et ultrastructurale des péricaryones neurosécréteurs latéraux de Locusta précise leur nombre et leur localisation. Elle révèle que le neurosécrétat latéral est semblable morphologiquement (forme et diamètre des granules élémentaires) au neurosécrétat A de la pars intercerebralis. Cependant, il en diffère histochimiquement par la présence d'une composante glucidique. Elle confirme l'hypothèse émise pour les péricaryones neurosécréteurs de la pars intercerebralis (Girardie et Girardie, 1967), de l'unicité cellulaire chez Locusta des types A et B selon la nomenclature de Johansson (1958). Elle suggère que les péricaryones latéraux pourraient être des cellules neurosécrétrices très actives.
    Notizen: Summary The number (8 to 12) and position of the lateral neurosecretory cells have been established in Locusta by a histological, histochemical and ultrastructural study. The neurosecretory material of the lateral cells contains glycoprotein and is, in this way, histochemically different from medial A cells neurosecretory material. However, the morphological aspect (shape, diameter) of elementary dense core vesicles in the lateral and medial A neurosecretory cells is similar. This study confirms the idea (Girardie and Girardie, 1967) that, in Locusta, A cells and B cells (Johansson, 1958) are in fact two physiological aspects of one cell type. It also suggests that the lateral cells could be very active neurosecretory cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 29
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 146 (1973), S. 147-154 
    ISSN: 1432-0878
    Schlagwort(e): Peripheral autonomic innervation ; Ureterovesical ganglia ; Parasympathetic postganglionic synapse ; Sympathetic postganglionic synapse ; Denervated bladder ; Acetylcholinesterase ; Catecholamine ; Histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Histochemical techniques for acetylcholinesterase and catecholamine show that ureterovesical ganglia of both cat and dog contain dense intraganglionic cholinergic and adrenergic plexuses. Ramifications of both plexuses surround most cholinergic and adrenergic ganglion cell bodies as pericellular synaptic plexuses. Similar pericellular plexuses exist around extraganglionic cholinergic and adrenergic ganglion cells. Both adrenergic and cholinergic synaptic fibers persist in denervated pregnaglionic nerve-free specimens, indicating that cholinergic synaptic fibers are postganglionic parasympathetic in nature. The presence of adrenergic (postganglionic sympathetic) and postganglionic parasympathetic synapses around cell bodies in ureterovesical ganglia provides a morphologic basis for the sympathoinhibitory and muscarinic parasympatho-excitatory phenomena described in these ganglia.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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