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  • Rat  (43)
  • Chromatographie, Dünnschicht  (30)
  • Lysosomes
  • Springer  (85)
  • Cham :Springer International Publishing :
  • Frontiers Media SA
  • 2020-2024
  • 2020-2022
  • 1970-1974  (85)
  • 1974  (55)
  • 1971  (30)
Collection
Publisher
  • Springer  (85)
  • Cham :Springer International Publishing :
  • Frontiers Media SA
Years
  • 2020-2024
  • 2020-2022
  • 1970-1974  (85)
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 14 (1974), S. 153-160 
    ISSN: 1432-0827
    Keywords: Lysosomes ; Bone ; Resorption ; Osteoclast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des techniques histochimiques de microscope photonique et électronique montrent que les ostéoclastes métaphysaires chez des rats “sans incisive” présentent des quantités plus importantes de phosphatase acide, d'acryl sulfatase et de trimétaphosphatase acide lysosomiales. L'activité en phosphatase lysosomiale à pH neutre est aussi plus élevée dans les ostéoclastes métaphysaires, sauf dans les cellules situées sous la métaphyse, où l'enzyme est absente. L'absence de résorption de la matrice organique semble en rapport avec l'absence de bordures en brosse et une absence d'enzyme lysosomiale extracellulaire. Malgré cette absence, une dissolution de cristaux inorganiques a été mise en évidence au microscope électronique, suggérant que la dissolution minérale est un processus distinct de la désintégration enzymatique de la matrice organique.
    Abstract: Zusammenfassung Histochemische Techniken für Licht- und Elektronenmikroskopie zeigten, daß metaphysäre Osteoklasten “Schneidezahl-loser” (SL) Ratten erhöhte Mengen von lysosomaler saurer Phosphatase, von Arylsulfatase und von saurer Trimetaphosphatase enthielten. Die Aktivität der lysosomalen Phosphatase bei neutralem pH war in den metaphysären Osteoklasten ebenfalls erhöht, außer in den Zellen direkt unterhalb der Wachstumsplatte, wo dieses Enzym nicht vorkam. Es konnte überhaupt keine Resorption der organischen Matrix festgestellt werden, was übereinzustimmen schien mit der Abwesenheit eines gekräuselten Saumes und einer gleichzeitigen Abwesenheit des extrazellulären lysosomalen Enzyms. Trotzdem wurde im Elektronenmikroskop das Verschwinden anorganischer Kristalle festgestellt, was darauf schließen läßt, daß die Auflösung des Minerals nicht derselbe Vorgang ist wie die enzymatische Auflösung der organischen Matrix.
    Notes: Abstract Histochemical techniques for light and electron microscopy showed that metaphyseal osteoclasts in “incisors absent” rats contained greater than normal amounts of lysosomal acid phosphatase, aryl sulfatase and acid trimetaphosphatase. Lysosomal phosphatase activity at neutral pH was also elevated in the metaphyseal osteoclasts except in those cells immediately beneath the growth plate, where this enzyme was absent. The failure of any discernable resorption of organic matrix appeared to correlate with the absence of a ruffled border and a concomittant absence of extracellular lysosomal enzyme. Despite this failure, electron microscopic evidence of inorganic crystal removal was noted, suggesting that mineral dissolution represents a separate process from the enzymatic breakdown of organic matrix.
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  • 2
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    Calcified tissue international 14 (1974), S. 283-289 
    ISSN: 1432-0827
    Keywords: Sodium fluoride ; Osteoporosis ; Bone ; Strength ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'utilisation thérapeutique de fluorure de sodium a été recommandée dans le traitement de diverses maladies osseuses ostéopéniques. Cet emploi est basé principalement sur les effects ostéosclérotiques bien connus du fluorure de sodium, mais on connait mal son effet sur la force de résistance osseuse. L'influence de diverses concentrations de fluorure de sodium sur la force de résistance osseuse de jeunes rats soumis à des régimes riches et pauvres en calcium a été étudiée. L'administration de fluorure de sodium augmente le diamètre osseux, indiquant une stimulation de la formation de l'os périosté, mais la force de résistance osseuse est réduite ou non modifiée par l'ingestion de fluor.
    Abstract: Zusammenfassung Die therapeutische Verwendung von Natriumfluorid ist für eine Anzahl von Knochenmangel-Krankheiten empfohlen worden. Die Empfehlungen basieren hauptsächlich auf den bekannten osteosklerotischen Wirkungen von Natriumfluorid; über dessen Effekt auf die Knochenstärke ist wenig bekannt. In dieser Arbeit wurde der Einfluß verschiedener Konzentrationen von Natriumfluorid auf die Knochenstärken von wachsenden Ratten mit hoher und niederer Calciumeinnahme untersucht. Die Verabreichung von Natriumfluorid erhöhte den Knochendurchmesser, was auf eine Stimulierung der Periostbildung hinwies, die Knochenstärke wurde jedoch durch Fluorideinnahme herabgesetzt oder nicht beeinflußt.
    Notes: Abstract The therapeutic use of sodium fluoride has been recommended in a variety of osteopenic bone diseases. The recommendations are based mainly on the known osteosclerotic effects of sodium fluoride and little information is available as to its effect on bone strength. The influence of various concentrations of sodium fluoride on bone strength in growing rats on high and low calcium diets was studied. The administration of sodium fluoride increased bone diameter, indicating stimulation of periosteal bone formation, but bone strength was reduced or not affected by fluoride ingestion.
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  • 3
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    Archives of microbiology 98 (1974), S. 115-126 
    ISSN: 1432-072X
    Keywords: Endocytosis ; Tetrahymena ; Lysosomes ; Exocytosis ; Acid Hydrolases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Endocytosis of yeast cells by Tetrahymena pyriformis GL for a period of 2.5 h produced changes in cellular acid hydrolases. Acid phosphatase, acid deoxyribonuclease and acid proteinase activities were markedly increased, whereas there was a decrease in acid ribonuclease activity and little change in α-glucosidase activity. These alterations do not appear to be due to any alteration in the rates of secretion of these enzymes into the milieu. Evidence is presented that the cellular enzyme increases found upon endocytosis of yeast reflect changes in lysosomal enzymes, because it was shown that the acid phosphatase activity increase resulted in an increased amount of latent enzyme within the cell. The results also support the idea that there are at least 3 distinct populations of lysosomes, in addition to phagolysosomes, present in Tetrahymena pyriformis GL, with different modes of formation. There appears to be a large excess of lysosomes, uncombined with phagosomes, present in these fed cells since latency averaged 66% in broken-cell preparations which contained very few intact phagolysosomes. The phagolysosomal acid phophatase activity cannot account for more than 34% of that present in the cell. The endocytosis of yeast in the presence of growth medium resulted in a marked drop in the rate of cell division as compared to cells growing in the growth medium alone. The results are discussed.
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  • 4
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    Cell & tissue research 112 (1971), S. 97-119 
    ISSN: 1432-0878
    Keywords: Insects ; Epicuticle secretion ; Golgi system ; Lysosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les modifications cytologiques des cellules épidermiques sécrétant la cuticule sternale et pleurale de l'adulte deT. molitor sont étudiées pendant la formation et l'évolution de l'épicuticule externe et interne. L'épicuticule externe et interne sont sécrétées de la même façon par condensation de matériel diffus au-dessus de l'apex des microvillosités. Un cycle hétérolytique est mis en évidence par l'emploi de peroxydase injectée dans l'espace exuvial: la peroxydase est captée par de grosses vésicules revêtues et incorporée dans des corps multivésiculaires apicaux. Par comptage des différentes populations de vésicules, des variations nettes dans l'intensité de la pinocytose sont mises en évidence. Ces variations semblent en rapport non pas avec la digestion de l'ancienne cuticule mais avec les différences de nature et de structure des composants cuticulaires. L'hypothèse du contrôle de la sécrétion épidermique par les phénomènes de pinocytose énoncée par Locke (1969) est confirmée. Des vésicules d'origine golgiennes sont secrétées surtout après la formation de l'épicuticule et ne sont donc pas à l'origine du matériel épicuticulaire, mais il est possible qu'elles jouent un rôle dans l'évolution ultérieure des structures épicuticulaires.
    Notes: Summary The cytological modifications of the epidermal cells secreting sternal and pleural cuticle of adultTenebrio are studied, specially during the formation and evolution of the outer and inner epicuticle. Both layers are secreted by condensation of diffuse material just above the epidermal microvilli. There is no peculiar phase without microvilli when inner epicuticle is formed. During the secretion of pre-ecdysial cuticle, the epidermal cell is characterized by an heterolytic process which is demonstrated by peroxidase injection into the ecdysial space: horseradish peroxidase is absorbed by large pinocytic coated vesicles which discharge their content into multivesicular bodies, after the loss of their coat. The intensity of pinocytosis is studied by vesicles counts at different stages of the pupal life. These counts show a pinocytic peak when the inner epicuticle is formed. When the epicuticular barrier is completely secreted, exogenous peroxidase is no more absorbed, but morphological study and counts show that pinocytosis still occurs. This demonstrates that epidermis cannot absorb macromolecules arising from the digested old cuticle since digestion occurs after the completion of adult epicuticle. Locke's hypothesis about the “control of the extracellular subcuticular environment” by pinocytosis is confirmed. The Golgi complexes are involved in lytic process with their small coated vesicles and in secretion of cuticular material with their large dense secretory vesicles, but according to vesicle counts, the secretory vesicles are not concerned in epicuticle formation since their apparition is posterior to the deposition of the inner epicuticle.
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  • 5
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    Cell & tissue research 115 (1971), S. 524-542 
    ISSN: 1432-0878
    Keywords: Spleen ; Rat-Marginal sinus ; Reticuloendothelial system ; Lysosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the rat spleen cells are found staining with aldehyde fuchsin (AF-cells). Most of these cells are localized at the periphery of the follicles, at the inner border of the marginal sinus. They probably develop in situ. Comparable cells occur in other lymphoid organs. They are able to phagocytize, and resemble also histochemically red pulp macrophages. The aldehydefuchsinophilic granules do not stain for mucopolysaccharides. On the ultrastructural level the aldehydefuchsinophilic granules are represented by cytoplasmic bodies with a faintly granulated matrix. Because of their single membrane and the varying positive reaction on acid phosphatase these bodies are considered to be secondary lysosomes or residual bodies. They contain different materials of unknown endogenous origin. In non-immunized animals the AF-cells fail to show the characteristic dendritic protrusions and infoldings of antigen trapping cells. The cells possess some characteristics of reticular cells e.g. association with reticulin, and electron dense patches on the innerside of the cell membrane at the contact areas. They can be classified among the phagocytic reticular cells forming part of the metalophilic cells in the spleen.
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  • 6
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    Cell & tissue research 116 (1971), S. 151-156 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Innervation ; Receptors ; Rat ; Pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation of the adrenal cortex of the rat and the pig is investigated with the electron microscope. Nerve fibers containing synaptic and two types of dense-cored vesicles come into contact with endocrine cells. There are no specialized pre- and postsynaptic membranes. The synaptic cleft is about 200 Å wide. Generally the basement membrane between nerve and cell is absent. These observations are discussed on the base of more recent experimental findings. Small fibers having an average diameter of about 0.2 to 0.5 μ and containing only tubules and filaments are considered to represent parts of an afferent nervous system.
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  • 7
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    Cell & tissue research 118 (1971), S. 283-296 
    ISSN: 1432-0878
    Keywords: Blood platelets ; Lysosomes ; Acid phosphatase ; Aggregation ; Cell fractionation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Aufgrund biophysikalischer, biochemischer und ultrastruktureller Eigenschaften lassen sich in intakten oder fraktionierten Blutplättchen von Mensch und Schwein verschiedene Funktionstypen von alpha-Granulomer unterscheiden. Ein elektronen dichter, oft Mikrotubuli aufweisender Typ ist durch Zentrifugation von einem helleren mit fibrillärer Streifung abzusetzen. Außerdem läßt sich eine Fraktion vesikulärer Strukturen darstellen. Bei biochemischer Analyse ist die Hauptmenge der lysosomalen Hydrolasen Cathepsin und beta-Glucuronidase mit dem weniger dichten Typ der alpha-Granula vergesellschaftet, während sich der Hauptteil der sauren Phosphatase in der Vesikelfraktion befindet. Zytotopochemisch erscheint dieses Enzym immer strukturgebunden, sowohl an beiden Typen von alpha-Granula, als auch in den Vesikeln. Das Vesikelsystem spielt bei der Stoffaufnahme in Plättchen eine Rolle und wird auch als gamma-Granulomer, surface connected system oder canaliculäres System bezeichnet. Bei der Degranulation der Plättchen wird — wie die Enzymlokalisation in diesem Falle zeigt — Granulainhalt über das vesikuläre System in das Außenmedium abgegeben. Saure Phosphatase kann auch in Phagozytosevakuolen nachgewiesen werden. Elektronenoptisch läßt sich der Übergang von alpha-Granula in vesikuläre Strukturen erkennen. Die Befunde zeigen, daß zwischen alpha-Granula und Vesikelsystem enge Beziehungen bestehen. Zusammen bilden sie eine funktionelle Einheit, die neben der Stoffaufnahme auch die Funktion der Abgabe von Substanzen aus den Plättchen erfüllt. Schließlich findet die Digestion aufgenommener Stoffe dort statt.
    Notes: Summary Biochemical and ultrastructural findings from intact and fractionated pig and human blood platelets indicate the presence of different types of alpha granules. An electron dense type can be distinguished from a lighter one with a fibrillar matrix. The major part of the lysosomal hydrolases beta-glucuronidase and cathepsin is associated with the lighter granules. Most of the acid phosphatase appears in the vesicle fraction. The ultracytochemical investigation shows the acid phosphatase bound to both types of granules or vesicles. This enzyme is visible in the narrow spaces between the outer membranes of aggregated thrombocytes. Furthermore, there can be seen the transformation of alpha granules into vesicles and vesicles, which contain acid phosphatase releasing their contents into the extracellular medium. Thus the significance of the vesicle system for the release of substances out of the platelet seems to be proved. From this point of view the different types could be considered as alpha granules in different functional stages.
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  • 8
    ISSN: 1432-0878
    Keywords: Adrenergic neurons ; “Short” and “long” systems ; Pre- and postnatal development ; Peripheral organs ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The adrenergic innervation in the submaxillary gland, heart, kidney, small intestine, and accessory male genital organs and the development of the adrenal chromaffin cells and the sympathetic ganglia were studied in the rat from 15 days post coitum to 16 days post partum using the fluorescence histochemical method of Falck and Hillarp. The postnatal development of the noradrenaline concentrations in the heart and vas deferens was followed by fluorometric determinations. At about 15 days post coitum, the anlagen of the sympathetic chains were well visible in the form of two dorsal segmented columns of small branching sympathicoblasts exhibiting an intense catecholamine fluorescence. In the midline, ventrally to these two anlagen, another column of sympathicoblasts developed; this seemed to give rise to the prevertebral ganglia and to the short adrenergic neurons supplying the internal genital organs. At the level of the adrenal anlagen, small intensely fluorescent chromaffin cells were collected in two bilateral groups which became enclosed by adreno-cortical cells. This enclosure was, however, not complete even at two weeks post partum. Bundles of growing sympathetic nerves were visible in the periphery of the various organs studied at 19–21 days post coitum. A terminal innervation of the organs suggestive of a functional transmitter mechanism did not start to establish until at or immediately after birth. The final pattern of innervation was usually reached at about one week post partum, and the following development proceeded largely in the form of a quantitative increase in the number of nerves participating in the innervation apparatus. The adult level of noradrenaline in the heart and vas deferens was reached three to five weeks after birth. The small intestine was an exception in that the final pattern of innervation in the wall was attained immediately after birth. There was no overt difference in the rate of development of the terminal sympathetic innervation in organs supplied by short adrenergic neurons (accessory male genital organs) compared to the innervation of the submaxillary gland, heart and kidney, which receive classical long adrenergic neurons.
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  • 9
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    Cell & tissue research 119 (1971), S. 58-67 
    ISSN: 1432-0878
    Keywords: Ovary ; Rat ; Fowl ; Granulosa cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The granulosa cells of the ovarian follicle of the rat and the domestic fowl have been studied with the light and electron microscope. The nuclei of the granulosa cells were irregular with indentations and large in proportion to the cytoplasm of the cell. The mitochondria had a dense, dark matrix with only few cristac. The Golgi apparatus was moderately developed, located towards the oocyte in a juxtanuclear position. The endoplasmic reticulum was rather sparse. Lipid droplets were only occasionally encountered. Microtubules were regularly observed. The functions of the granulosa cells are discussed. Compared with the steroid-producing cells of the theca interna of the same follicles, the granulosa cells primarily are the nursing cells for the growing oocyte and mainly have the characteristics of protein forming cells.
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  • 10
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    Cell & tissue research 122 (1971), S. 283-300 
    ISSN: 1432-0878
    Keywords: Paraventricular nucleus ; Rat ; Synthesis of hormones ; Acid phosphatase ; Osmium impregnation ; Neurosecretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural features of the paraventricular neurones of the non-treated rat are presented comparing them with those of the supraoptic neurones. No striking differences are seen between the general electron microscopic characteristics of the paraventricular and supraoptic neurones. The importance of adequate fixation to obtain good preservation of the neurones is emphasized, since inadequate fixation can cause e.g. artefactual appearance of “dark neurones”. The previously presented classification of the neurosecretory neurones into two categories (e.g. “light and dark neurones”) on the basis of the number of ribosomes is not considered justifiable, since their number can vary to a very great extent even within a single cell. The synthesis of neurosecretory products in the paraventricular neurones obviously follows the general mode of the synthesis of secretory proteins: ribosomes—RER—Golgi complex—secretory vesicles. On the basis of the localization of heavy metal deposits after osmium impregnation and demonstration of acid phosphatase the Golgi complex of the paraventricular neurones is found to be polarized. The direction of the polarity is discussed. The substructures of the dense cores of the neurosecretory granules and of the contents of the lysosomal dense bodies are nearly identical. Therefore it is considered impossible to determine positively the nature of the dark condensed material within the Golgi complex. The characteristics of the immature neurosecretory granules and the possibility of releasing neurosecretory products into the cytoplasm already within the perikarya are speculated.
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  • 11
    ISSN: 1432-0878
    Keywords: Smooth muscle ; Two-filament system ; Small intestine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structure of glycerinated smooth muscle from small intestine of adult rat was investigated by electron microscopy. In the central parts of the tissue blocks a two-filament system was found, consisting of parallel thick and thin filaments with regularly spaced interconnections, closely resembling that of striated muscle. In the peripheral parts of the blocks only thin filaments were found. The thin filaments were identified as actin by the formation of arrowhead complexes after incubation with heavy meromyosin.
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  • 12
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    Cell & tissue research 121 (1971), S. 531-547 
    ISSN: 1432-0878
    Keywords: Helical polyribosomes ; Skeletal muscle ; Polysomes ; Levator ani ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The localization and configurations of ribosomes in mature white skeletal muscle fibers of the rat were investigated. Differential visualization of ribosomes and glycogen granules was obtained by fixation with glutaraldehyde only and staining of the sections with uranyl acetate. Ribosomes are then electron dense and glycogen granules electron transparent. Their identity was ascertained by selective extractions of ribonucleic acid and polysaccharide. The vast majority of the ribosomes is not membrane-bound. They are located intermyofibrillarly (predominantly at the level of the I-bands), beneath the sarcolemma, and in the paranuclear cones of sarcoplasm. Occasionally short stretches of granular reticulum occur, often as characteristic double walled vesicles with ribosomes on the inner membrane only. Three main types of polysomal configurations are observed: rosettes of 4 to 6 ribosomes, helical arrays, and whorls of up to about 25 probably membrane-bound ribosomes. The average number of ribosomes in the extended helical configurations is estimated to be about 60. It is argued that these helices represent the polysomes instrumental in the synthesis of the large subunits of myosin. It is emphasized that helical polyribosomes are by no means typical of striated muscle, but probably represent a common configuration of large free polysomes.
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  • 13
    ISSN: 1432-0878
    Keywords: LRF ; Hypothalamic localization ; Rat ; Ependyma ; Glia ; Light and electron microscopic Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Light and electron microscopic autoradiographic analysis of the medial basal hypothalamus of rat brains incubated for 30 and 60 minutes in tritiated luteinizing releasing factor (3H-LRF) revealed selective uptake in the form of silver grains over specialized ependyma (tanycytes) and perivascular glial cells in the palisade-contact zone of the median eminence. The functional capacity of tanycytes and glia are discussed in light of these data.
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  • 14
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    Cell & tissue research 150 (1974), S. 493-496 
    ISSN: 1432-0878
    Keywords: Serotonin ; Neurotransmitter ; Myenteric plexus ; Rat ; Histofluorescence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Several recent studies suggested that serotonergic neuron-like elements are present in the guinea pig ileum. The present paper reports an extensive study of the digestive tract of the rat with the use of a histofluorescence technique. Administration of the serotonin precursor, tryptophan, associated with a monoamine oxidase inhibitor, did not allow histochemical demonstration of rapidly fading, yellow fluorescent, 6-hydroxydopamine-resistant neurons; conversely such neurons were readily detected in the brain. It is concluded that serotonergic neuron-like elements cannot be detected histochemically in the rat myenteric plexus area after chemical sympathectomy.
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  • 15
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    Cell & tissue research 151 (1974), S. 457-469 
    ISSN: 1432-0878
    Keywords: Juxtaglomerular apparatus ; Rat ; Adrenalectomy ; Renin and secretory granules ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Reaktion des juxtaglomerulären Apparates auf Adrenalektomie wurde untersucht. Im Stadium der Nebenniereninsuffizienz, sechs Tage nach der Operation, wurde quantitativ morphometrisch eine Abnahme der Volumendichte der Sekretgranula (von 32% auf 16%) festgestellt. Golgi-Apparat und Ergastoplasma proliferieren stark, wobei insbesondere die erweiterten Cisternen des Ergastoplasmas auffallen.
    Notes: Summary The response of the Juxtaglomerular apparatus to bilateral adrenalectomy was studied in rats. After the sixth postoperative day, symptoms of severe adrenal insufficiency had developed. In the Juxtaglomerular cells, the volume density of the secretory granules decreased from 32% to 16%. The Golgi apparatus and rough endoplasmic reticulum underwent considerable proliferation, the latter showing strikingly enlarged cisternae.
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  • 16
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    Cell & tissue research 151 (1974), S. 525-536 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex differences ; Gonadal hormones ; Karyometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adrenal glands of adult female rats are heavier than the glands of corresponding male rats. Postpubertal orchiectomy increases the adrenal weight, an effect restored by testosterone replacement. Under the same conditions ovariectomy of 8 weeks duration does not change the adrenal weight while estradiol replacement enhances the relative adrenal weight. Karyometric studies have shown that nuclei in the female zona fasciculata cells are larger (app. 18%) than those of the male. Similar but only slight differences (2%) were observed in the zona reticularis. Orchiectomy results in enlargement of cell nuclei within all zones of the adrenal cortex; testosterone replacement has the opposite effect. Ovariectomy of 8 weeks duration slightly enhances the volume of nuclei of the zona glomerulosa cells, has no effect on the nuclei of the zona fasciculata and reduces the volume of nuclei in the zona reticularis. Estradiol replacement reduces the volume of nuclei of the zona glomerulosa cells but increases nuclear volume in the zona fasciculata and in the zona reticularis. Thus testosterone has an inhibitory effect on the adrenal cortex of the rat while the physiologic effect of estradiol on the morphology of this gland, particularly on the zona fasciculata cells is rather dubious. The author wishes to thank Mrs. B. Westerska and Miss K. Siejak for excellent technical assistance.
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  • 17
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    Cell & tissue research 151 (1974), S. 537-547 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex differences ; Gonadal hormone ; Stereologic studies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adult female rats have heavier adrenals than males. Orchiectomy increases the adrenal weight, an effect reversed by testosterone. Neither ovariectomy nor estradiol replacement has an effect on absolute adrenal weight. The stereologic analysis of the volume fractions of particular adrenocortical zones have shown that the volume fraction of the zona glomerulosa in females is smaller as compared with males. On the contrary, the volume fractions of the fasciculata and reticularis zones are higher in female than in male rats. In both sexes gonadectomy and gonadal hormone replacement has an effect on the volume fractions of particular adrenocortical zones, these changes being more pronounced due to orchiectomy or testosterone replacement. The adrenal cortex of all experimental groups contains a similar quantity of parenchymal cells. The cytoplasm volume of a single adrenocortical cell is higher in all zones of the female adrenals as compared with the male. Orchiectomy increases the volume of the cytoplasm in fasciculata and reticularis cells. This effect was reversed by testosterone. Neither ovariectomy nor estradiol replacement has an effect on the volume of the cytoplasm in the fasciculata and reticularis cells. These studies have shown that sex differences with regards to rat adrenal size and weight depend upon the “physiologic atrophy” of the male adrenal cortex, while neither ovariectomy (8 weeks after operation) nor estradiol replacement has a conspicuous effect on the morphologic changes of this gland.
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  • 18
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    Cell & tissue research 155 (1974), S. 455-473 
    ISSN: 1432-0878
    Keywords: Lysosomes ; Liver ; Ageing ; Exocytosis ; Thorotrast ; Electron microscopy, Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Lysosomes in mouse liver parenchymal cells have been marked by intravenous injection of Thorotrast. They were subsequently followed in a time sequence from five hours up to sixteen weeks after injection. At two days after injection the majority of the lysosomes was heavily loaded with marker particles, while endocytosis was no longer observed. From six days after injection Thorotrast was partly accumulated in very large lysosomes (conglomerates) with mean diameters up to 2.5 μm. As the time after injection advanced the Thorotrast content of the cells was reduced while most of the remaining marker substance became concentrated in the conglomerates. Many Thorotrast conglomerates were shown to contain acid phosphatase and some of them were able to fuse with functionally younger lysosomes which were marked with colloidal gold. Morphometric analysis showed an increase in the volume density of the dense body population between 0 and 2 days after injection, followed by a decrease between 2 and 11 days. The observed decrease is probably caused by exocytosis of the contents of Thorotrast containing lysosomes in bile capillaries.
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  • 19
    ISSN: 1432-0878
    Keywords: Avian follicles ; Oocytes ; Transosomes ; Lysosomes ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopy has been utilized to determine fates of sacs of ribosomes (variously termed “transosomes”, “unique organelles”, or “lining bodies”) formed in the follicular cells of avian follicles and subsequently entering-or being taken in-by the oocytes. Small follicles (0.5 mm diameter) of laying hens, a hen afflicted with Marek's disease and prelaying pullets were examined in this regard. In the case of the hen with Marek's disease and the prelaying pullets, sacs of ribosomes were found to be present within the oocyte but those present in the interior of the cell were in the form of digestive vacuoles. In a fourth group of hens, receiving actinomycin D, larger oocytes (2.0 mm diameter) exhibited breakdown of the membranous vesicles in which the sacs of ribosomes entered the oocyte, as well as dissolution of membranes surrounding the forming yolk granules and the membranes of coated vesicles. Annulate lamellae were present in oocytes of the hen afflicted with Marek's disease and appeared within at least 24 hours in oocytes from hens receiving actinomycin D.
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  • 20
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    Cell & tissue research 147 (1974), S. 259-269 
    ISSN: 1432-0878
    Keywords: Nerve endings ; Hair ; Rat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Palisade-shaped nerve endings of the small normal hairs of the rat snout were examined with the electron microscope (fixation by perfusion). The terminals are located inside the ‘glassy membrane’ in the area of the neck of the hair root. The 10–20 radially arranged terminal axons are in direct contact with the basement membrane of the epithelium of the external root sheath. The axons are surrounded on all sides by leaf-shaped processes of the Schwann cells. The surfaces of these cell processes are marked by numerous vesicle-like invaginations (approx. 1000 Å dia.). Transverse sections from several areas of the palisadeshaped nerve endings are compared with longitudinal sections. In the upper area ‘empty’ vesicles (approx. 500–600 Å in diameter) occur, along with electron-dense vesicles (approx. 800–1100 Å in diameter); in the middle area, the axons are distended and contain accumulations of mitochondria.
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  • 21
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    Cell & tissue research 147 (1974), S. 183-190 
    ISSN: 1432-0878
    Keywords: Kidney ; Rat ; Bowman's capsule ; Experimental hypertension
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The parietal layer of Bowman's capsule was examined in the rat in control animals and in animals made hypertensive by treatment with desoxycorticosterone acetatesaline and by clipping of the renal artery. At an early stage of elevation of blood pressure and, occasionally, prior to elevation of blood pressure, the epithelial cells of this layer showed basal cytoplasmic protrusion and reduplication accompanied by an increase in the thickness of the basement membrane. These changes preceded evidence of glomerular or renal arteriolar pathology. They presumably reflect either a response of this layer to increased blood pressure and modified glomerular function, or a direct effect of the factors that also induces blood pressure elevation. In either case, they imply a greater functional significance for the parietal layer than has usually been attributed to it.
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  • 22
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    Cell & tissue research 148 (1974), S. 57-67 
    ISSN: 1432-0878
    Keywords: Prostate ; Rat ; Cyproterone ; Alterations ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The dorsal lobe and the coagulating gland of the rat prostate were studied after administration of the anti-androgenic compound Cyp A for varying periods (7–20 days). There was a general involution of the organs with macroscopic atrophy and reduced amount of secretory material. Ultrastructurally the cells were pale, contained less organelles as compared with the controls, loss of cytoplasm and reduction both of cell height and width. The major changes also included reduction of the Golgi area, the rough endoplasmic reticulum and the number of free ribosomes. Within the dorsal lobe prominent nuclear changes were found, comprising different types of intranuclear inclusions of membranous configurations. The alterations observed in the present study are similar to the changes which were found in castrated animals and are consistent with atrophy. The results are discussed in relation to the available biochemical and autoradiographic data on the different lobes.
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  • 23
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    Cell & tissue research 150 (1974), S. 95-105 
    ISSN: 1432-0878
    Keywords: Mucosal mast cells ; Rat ; Compound 48/80 ; Degranulation, Release ; Light microscopy ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mast cells in the tongue and lamina propria of the duodenal mucosa, representing two cell types with different morphological, histochemical and functional properties have been studied under the electron microscope. Both cell types were found to contain similar moderately electron dense and homogeneous granules surrounded by a tight membrane constituting the basic ultrastructural characteristics of mast cells. The mucosal mast cells, however, contained fewer granules per cell and the individual granules often exhibited considerable variation in size. In addition the mucosal mast cells, unlike those of the tongue, peritoneum and skin, had a smooth plasma membrane lacking microvilli and possessed irregularly shaped or lobulated nuclei. In the tongue mast cells, administration of Compound 48/80 caused the formation of vacuoles around the granules, expulsion of granules from the cells and disintegration of the granular matrix, but no changes that could be attributed to 48/80 could be found in the mucosal mast cells.
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  • 24
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    Cell & tissue research 154 (1974), S. 443-470 
    ISSN: 1432-0878
    Keywords: Oocytes and T-prospermatogonia ; Rat ; Quantitative analysis ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Bei der Ratte findet die sexuelle Differenzierung der Gonade zwischen dem 14. und 15. Tag post conceptionem (p.c.) statt. Während dieser Zeit teilen sich die Oogonien und deren Parallelpopulation—die M-prospermatogonien (multiplying prospermatogonia) oder I-Gonocyten—sehr häufig. Um den 17. Tag p.c. tritt die letzte Generation der Oogonien bzw. der M-prospermatogonien in die Mitose. Die Mitosen bilden häufig “synchronisierte Gruppen”. Die postmitotischen Kerne ihrer Tochterzellen—der Oocyten und der T 1 prospermatogonien (primary transitional prospermatogonia) oder II-Gonocyten—sind klein. Ihr Chromatin ist in Form gröberer Schollen der Kernmembran angelagert. Auf diese Weise kommt das typische “krustenförmige” Aussehen bzw. die Ähnlichkeit mit den Prophasen der Oogonien und M-prospermatogonien zustande. Die Oocyten durchlaufen zunächst die G1-phase (etwa 10 Std Dauer) und treten dann—am Ende des Präleptotänstadiums—in die S-phase. Dann passieren sie die verschiedenen Stadien der meiotischen Prophase und treten vom 3. Tag post partum (p.p.) ab in das Dictyotänstadium. Die T1-prospermatogonien hingegen befinden sich etwa 10 Tage lang in der G1-phase, ohne wesentliche morphologische Veränderungen aufzuweisen. Vom 4. Tag p.p. an durchlaufen sie die S-Phase. Die S-Phasen-Dauer (D-S) beider Zellarten beträgt 11.5 Std und wurde durch Doppelmarkierung mit 14C- und 3H-Thymidin bestimmt. Als am besten geeignete Termine für die Bestimmung der D-S erwiesen sich bei den Oocyten der 18. Tag p.c. und bei den T1-prospermatogonien der 5. Tag p.p. Zu diesen beiden Zeitpunkten war die Anzahl der in die S-phase ein-und austretenden Oocyten bzw. T1-prospermatogonien gleich, die Zellen in S-phase befanden sich im “steady state”. Das Kernvolumen der Oogonien und M-prospermatogonien ist etwa doppelt so groß wie das der postmitotischen Oocyten und T1-prospermatogonien. Bis zum 5. Tage p.p. nimmt das Kernvolumen der Oocyten und T1-prospermatogonien um etwa das Fünffache zu. Der Degenerationsindex der Oocyten liegt wesentlich höher als der der T1-prospermatogonien; er ist postnatal besonders hoch. Aus den T1-prospermatogonien gehen am 4. und 5. Tage p.p. durch Teilung die T 2-prospermatogonien (secondary transitional prospermatogonia) hervor. Die Kerne dieses Zelltyps sind etwas kleiner also die der T1-prospermatogonien. Die T2-prospermatogonien treten am 6. Tage p.p. in die Mitose; es entstehen die ersten A-spermatogonien.
    Notes: Summary In the rat (Wistar-WU) sexual differentiation of the gonads occurs between days 14 and 15 post conception (p.c.). At this time the oogonia and their parallel population — the M-prospermatogonia (I-gonocytes)—divide rapidly. On about day 17 p.c., the last generation of oogonia and M-prospermatogonia, frequently arranged in synchronized clusters, enters mitosis. The postmitotic nuclei of their daughter cells—oocytes and T 1-prospermatogonia (II-gonocytes)—are small; coarse flakes of chromatin are associated with the nuclear membrane causing the typical “crustlike” appearance and the similarity with the prophases of oogonia and M-prospermatogonia. After the oocytes have passed a G1-phase of approximately 10 hr, they enter the S-phase at the end of the preleptotene stage. Then they pass the different stages of the meiotic prophase until they enter the dictyate stage from 3 day post partum (p.p.) onwards. The T1-prospermatogonia, on the other hand, spend a long G1-phase of about 10 days without any conspicuous morphological change before entering the S-phase from day 4 p.p. onwards. The duration of the S-pbase (D-S) of both cell types—oocytes and T1-prospermatogonia—as determined by the double labeling method with 14C- and 3H-thymidine is found to be 11.5 hr. The most favourable time for determining the D-S was day 18 p.c. for the oocytes and day 5 p.p. for the T1-prospermatogonia. On these two days the balance was reached between the cells entering and leaving the S-phase. The nuclear volumes of the postmitotic oocytes and T1-prospermatogonia are approximately half the size of those of their precursors. Until day 5 p.p. the nuclear volumes of the oocytes and T1-prospermatogonia increase about fivefold. The degeneration index of the oocytes is considerably higher than that of the T1-prospermatogonia; postnatally it is especially high. T 2 prospermatogonia arise by mitosis of the T1-prospermatogonia on day 4 and 5 p.p. The nuclei of this cell type are smaller than those of T1-prospermatogonia. T2-prospermatogonia enter mitosis on day 6 p.p and give rise to A-spermatogonia.
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  • 25
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    Cell & tissue research 155 (1974), S. 231-243 
    ISSN: 1432-0878
    Keywords: Pinealocyte-resembling cells ; Habenular region ; Sympathetic nerve fibres ; Ontogenetic development ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cells of the pineal gland, the pineal stalk, and the lamina intercalaris contain 5-HT and are innervated by sympathetic nerve fibres. These peripheral nerve fibres continue rostrally from the lamina intercalaris and run into the central nervous tissue of stria medullaris and the habenular nuclei. Pharmacological treatment to increase the cellular 5-HT content revealed that the sympathetic fibres are in close relation to yellow fluorescent cells embedded in the brain tissue. These yellow fluorescent cells develop very late in the ontogenetic development (three weeks or more postnatally) and are preceded by ingrowth of sympathetic fibres into the brain tissue. The results support the hypothesis that the cells found in the habenular region are of pinealocyte rather than neuronal nature, but it is possible that they differ in certain aspects from the cells of the pineal gland proper.
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  • 26
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    Cell & tissue research 112 (1971), S. 247-265 
    ISSN: 1432-0878
    Keywords: Parafollicular cells (C-cells) ; Secretory cycle ; Ca-Metabolism ; Lysosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die parafollikulären Zellen der Rattenschilddrüse zeigen eine vom jeweiligen Funktionszustand abhängige Feinstruktur: 1. Zellen mit zahlreichen Granula, einem ausgeprägten Golgi-Apparat, gering entwickeltem granuliertem endoplasmatischem Retikulum und manchmal einigen dichten Körpern mit myelinähnlichen Figuren. 2. Zellen mit wenigen Granula und einem stark entwickelten endoplasmatischen Retikulum mit erweiterten Zisternen; diese Zellen können das Lumen des Follikels erreichen. 3. Einige degranulierte Zellen. — In den Schilddrüsen-Follikeln des Hundes konnten wir nur die ersten beiden Zellformen, aber keine degranulierten parafollikulären Zellen beobachten. Nach Ca++-Injektion findet man als Zeichen der Funktionsabhängigkeit der Feinstruktur eine Zunahme der Zellen mit stark entwickeltem endoplasmatischem Retikulum und nur geringer Granulation. Die dichten Körper mit myelinähnlichen Figuren zeigen saure Phosphataseaktivität. Es handelt sich deshalb wahrscheinlich um Restkörper, die aus Autolysosomen entstanden sind. Trotzdem zeigt sich nach Zufuhr von Ca++ und anschließender EDTA-Gabe keine eindeutige Zunahme der Lysosomenzahl. Zwischen follikulären und parafollikulären Zellen sind Axonanschnitte zu finden.
    Notes: Summary The parafollicular cells of the thyroid of the rat show different fine structures most likely in relation with different functional states: 1. Some cells contain numerous secretory granules, a well developed Golgi complex, a moderately developed rough endoplasmic reticulum and some dense bodies containing myelin figures. 2. Other parafollicular cells have few granules and a strongly developed rough endoplasmic reticulum with enlarged cisternes. They sometimes reach the lumen of the follicle. 3. Finally, a few parafollicular cells appear degranulated.—In dogs the degranulated parafollicular cells could not be observed. Following administration of Ca++ ions there is an increase of cells with strongly developed endoplasmic reticulum and only few granules. The dense bodies with myelin figures show acid phosphatase activity. Most likely they are residual bodies derived from autolysosomes. However, EDTA after stimulation of the cells by Ca++ does not significantly increase the number of parafollicular cells containing autolysosomes. Axons can be found between follicular and parafollicular cells.
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  • 27
    ISSN: 1432-0878
    Keywords: Ependyma ; Thiobarbiturate narcosis ; Cell nucleus shrinkage ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Im Ependym des Hypothalamus wurde das Verhalten der Zellkern-Membran nach ausgedehnter intraperitonealer Thiobarbiturat-Narkose untersucht. Die Kernmembran ist gefaltet, der Zellkern zeigt Zeichen von Schrumpfung. Diese Veränderung ist reversibel und wird nicht von der mit der Narkose verbundenen Entwässerung verursacht. Elektronenmikroskopische Untersuchungen lassen einen normalen Stoffwechsel vermuten, Zeichen von Pyknose fehlen.
    Notes: Summary Effects on the nuclear membrane were investigated in hypothalamic ependymal cells of the rat during prolonged intraperitoneal thiobarbiturate narcosis. The nuclear membrane of the nucleus was folded and the nucleus showed signs of shrinkage. These alterations were reversible and did not depend on the dehydration which developed during the narcosis. Ultrastructural signs and the absence of pyknosis suggested that metabolism during nuclear shrinkage may be normal.
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  • 28
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    Cell & tissue research 113 (1971), S. 157-173 
    ISSN: 1432-0878
    Keywords: Prostate ; Development ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The postnatal development of the rat prostate has been studied with the electron microscope. Major developmental changes begin during the second week after birth and involve organelles associated with the formation of secretions. The amount of granular endoplasmic reticulum and the size of the Golgi complex increase greatly. Large vacuoles that probably contain secretory material are formed, and the lumen of the prostatic acini appears to contain secreted material. Large lysosomes with polymorphic interiors are present as early as 10 days after birth, and they become numerous by the end of the third week. Differences in fine structure between the different lobes of the prostate are detectable in 10–14 day old rats. The subsequent differentiation of the granular endoplasmic reticulum into the forms characteristic of the different prostatic lobes is described. The initial changes in the prostate occur in advance of sexual maturity of the animal, and the adult appearance of the gland is attained by 4–5 weeks after birth.
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  • 29
    ISSN: 1432-0878
    Keywords: Neurosecretory cells ; Rat ; Cytoplasmic bodies resembling nucleoli ; Paranucleolar and coiled bodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A distinctive cytoplasmic inclusion, termed nucleolus-resembling body, was identified in the neurons, but not in the glial cells, of the medial vascular prechiasmatic gland, the preoptic recess and the anterior part of the suprachiasmatic area in the rat. This ultrastructure which lacks a limiting membrane is made of an entanglement of tightly packed filaments, 60–70 Å in diameter. Each filament consists of smaller units, 15–20 Å thick. Usually, only one such ultrastructure is present in a cell, but at time two were identified. It is present in most neurosecretory cells. It is surrounded by polyribosomes in the perikaryon of the nerve cells. Furthermore, it is linked to peripherally located ribosomes by means of filaments, 70 Å in diameter. A possible function in protein synthesis of structural components, such as neurofilaments, is hypothesized. Two distinctive fibrillar areas were identified in the nucleolus according to the tightness with which fibrils were packed together. Their significance is discussed. Nucleolar extrusions were never observed in our studies. Paranucleolar and coiled bodies were identified in the nuclear sap. The mechanism of formation and the significance of these bodies are discussed.
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  • 30
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    Cell & tissue research 115 (1971), S. 30-45 
    ISSN: 1432-0878
    Keywords: Adrenal Cortex ; ACTH ; Autoradiography ; Stereology ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The changes occurring in rat adrenocortical cells (zona fasciculata) during an 8 day period of treatment with ACTH, were investigated by morphometric and autoradiographic methods. The most important ultrastructural change consists in a conspicuous increase in the smooth endoplasmic reticulum, that accounts for about 50% of the total increase of cellular volume. Also the mitochondrial fraction shows a significant increase, which is found to be due both to the increment in the number of mitochondria per cell and to the increase in the mean volume of organelles themselves. The quantitative autoradiographic data, indicating an increment in the incorporation of 3H-orotate and 3H-leucine into adrenocortical cells of the treated animals, allow us to conclude that the ACTH-induced ultrastructural changes are the morphological expression of a stimulation of the cellular protein synthesis. Since mitochondria are largely autonomous in the synthesis of their enzymes and structural proteins, it is possible to hypothesize that ACTH also intervenes in the regulation of the mitochondrial protein synthesis.
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  • 31
    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Pars intermedia ; Corticotrophic cells ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Nos observations démontrent l'existence de deux types de cellules glandulaires dans la pars intermedia de l'hypophyse du rat: des cellules propres, à M.S.H., dont les grains de sécrétion sont détruits par la fixation osmiée et relativement bien conservés par la fixation au glutaraldéhyde; des cellules à petits grains denses, osmio-résistants, qui s'apparentent morphologiquement aux éléments corticotropes de l'antéhypophyse. L'existence bien connue d'A.C.T.H. ou, plus précisément, d'un facteur ≪A.C.T.H.-like≫ dans le lobe neuro-intermédiaire nous fait considérer comme très vraisemblable la nature corticotrope de ce deuxième type cellulaire de la pars intermedia.
    Notes: Summary Two types of glandular cells have been shown to occur in the intermediate lobe of the rat hypophysis: 1) M.S.H. producing cells whose secretory granules are destroyed by osmium fixation and relatively well preserved by glutaraldehyde fixation, 2) cells with small dense osmium resistant granules being morphologically similar to the corticotrophic cells of the anterior lobe. The well known occurrence of A.C.T.H. or, more precisely, of an “A.C.T.H.-like” factor in the neuro-intermediate lobe makes the corticotrophic nature of this second cell type very likely.
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  • 32
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    Cell & tissue research 117 (1971), S. 191-211 
    ISSN: 1432-0878
    Keywords: Sensory neurons ; Rat ; Nerve section ; Neurofilaments ; Neurofibrils
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Sensory neurons were examined in spinal ganglia of the rat 1 to 55 days after section of the plexus brachialis nerves. Only “light” neurons of the type A were investigated. Maximal reaction to axotomy was found 7 to 14 days after the operation. The majority of the axotomized perikarya developed central chromatolysis. In such neurons, Nissl bodies virtually disappeared from the central area of the neuron and formed a more or less continuous zone at the cell circumference. The cytocentrum became filled with large numbers of mitochondria, dense bodies and other organelles. Neurofilaments and microtubules were disarranged and ran at random among the accumulated particles. Microtubules were often more prominent in chromatolytic areas than neurofilaments. Both these organelles were rare in the peripheral areas filled with massed Nissl substance. Part of the neurons that did not show typical chromatolysis contained increased numbers of neurofilaments among Nissl bodies dispersed throughout the cytoplasm. Neurofilaments were roughly arrayed in bundles up to several microns wide; they were linked by cross-bridges and separated by distances of about 500 Å. Microtubules were rarely found in the filamentous areas. However, they were numerous in the axon hillock and in the initial segment where they formed fascicles similar to those described in normal neurons of other types. During the period from 14 to 55 days after axotomy, many perikarya recovering from chromatolysis contained enlarged bundles of neurofilaments with occasional microtubules among the restored Nissl bodies. Mean diameters of sensory neurons, measured 7 to 55 days after axotomy, in no instance exceeded those of contralateral control neurons. It thus appears that sensory perikarya do not increase in size either during the chromatolytic process or during the period of recovery.
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  • 33
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    Cell & tissue research 116 (1971), S. 136-150 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex difference ; ACTH ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Nebennierenrinde von 178 Sprague-Dawley-Ratten wurde elektronenmikroskopisch von der 1.–12. Lebenswoche unter Normalbedingungen sowie nach s.c. Injektion von 3 IE ACTH/100 g Körpergewicht innerhalb von 2 min — 24 Std untersucht. Ab der 5. Lebenswoche unterscheiden sich die Nebennieren von Weibchen im Bereich der äußeren Zona fasciculata durch Kernvergrößerung, größere Mitochondrien und kleindisperse Liposomen von denen der Männchen. Zyklusbedingte Schwankungen in der Ultrastruktur der weiblichen Nebennierenrinde bestehen nicht. Nach ACTH-Applikation nähert sich das Nebennierenbild des Männchen innerhalb von 30 min dem des unbehandelten Weibchens. Außerdem kommt es bei beiden Geschlechtern durch ACTH zu einer Dispersion und Reduktion der Liposomen, Vergrößerung des Golgiapparates und der Zellkerne, Ausweitung des endoplasmatischen Retikulums und Vermehrung der Mikrovilli. Der Geschlechtsdimorphismus wird funktionell erklärt.
    Notes: Summary 178 Sprague-Dawley-rats were studied by electron microscopy from the 1st to the 12th week of life under normal conditions and after s. c. injection of 3 I. U. ACTH/100 gbodyweight from 2 min to 24 hours. Beginning with the 5th week of life females differ from males by small dispersed liposomes and enlarged nuclei and mitochondria in the outer z. fasciculata. There is no change in the ultrastructure of the female adrenal cortex depending on the sexual cycle. After application of ACTH the adrenal cortex of males assimilates to the untreated females within 30 min. After ACTH-application both sexes show dispersion and reduction of liposomes, dilation of endoplasmatic reticulum, increasement of microvilli and enlargement of the Golgi apparatus. The sex-dimorphism is interpreted by functional differences.
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  • 34
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    Cell & tissue research 116 (1971), S. 464-476 
    ISSN: 1432-0878
    Keywords: Lung ; Alveolar macrophages ; Lysosomes ; Erythrophagocytosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Erythrophagoeytosis in vivo by cat alveolar macrophages was studied under the electron microscope by collecting the macrophages at 2 hours and 48 hours following the intratracheal injection of autologous blood. Considering the progressive ultrastructural modifications of the red blood cell plasma membrane, different successive stages were observed, corresponding to the hemolysis of the erythrocytes: 1. A recently engulfed erythrocyte appears unaltered within the phagocytic vacuole. 2. A dense layer, surrounding the plasma membrane of the red cell, is observed within the phagocytic vacuole. 3. The content of the vacuole is uniformly dense and the plasma membrane of the red cell exhibits discontinuous thickenings. 4. The whole vacuole appears very dense (hyperdense stage) and the plasma membrane is shown altered. The whole process of erythrophagocytosis is accompanied by an active fusion of the phagocytic vacuole with typical lysosomes and lysosomes containing crystal-like material. It is suggested that hemolysis may be explained in terms of enzymic digestion of the proteinic part of the plasma membrane of the erythrocyte.
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  • 35
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    Cell & tissue research 116 (1971), S. 477-486 
    ISSN: 1432-0878
    Keywords: Lung ; Alveolar macrophage ; Lysosomes ; Erythrophagocytosis ; Heinz bodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural analysis of the in vivo erythrophagocytosis by cat alveolar macrophages demonstrates a sequence of two successive events. The first consists of the destruction of the red blood cell membrane (hemolysis). The second corresponds to digestion of hemoglobin. This process is observed as a progressive and uniform clearing of the content of the phagocytic vacuole. An active fusion of typical lysosomes and of lysosomes containing crystal-like masses with the phagocytic vacuole continues to occur. At the terminal period small dense ferritin-like granules appear within the dissolving hemoglobin. During this process the swollen fragmented erythrocyte membrane, sometimes simulating Heinz bodies, persists along with lysosomal crystal-like masses. A lamellar structure of the altered erythrocyte plasma membrane is seldom observed. A diagram summarizes the entire process of destruction of the red blood cell (hemolysis and digestion) as observed following its engulfment by a cat alveolar macrophage.
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  • 36
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    Cell & tissue research 119 (1971), S. 378-383 
    ISSN: 1432-0878
    Keywords: Seminal vesicles ; Rat ; Epithelium ; Proliferation activity ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung An 12 männlichen weißen Wistarratten unterschiedlichen Alters wurde autoradiographisch die Proliferation des Samenblasenepithels zur Zeit der Pubertät geprüft. Die Tiere waren 21, 29, 40, 50, 60 und 180 Tage alt und erhielten 1 Std vor der Tötung durch Dekapitation 2,5 μC 3H-Thymidin/g Körpergewicht i. p. appliziert. Ausgewertet wurden Autoradiogramme nach einer Expositionszeit von 18 Tagen; bestimmt wurde der Prozentsatz der markierten Zellkerne (3H-Index). Im Gegensatz zu dem bekannten exponentiellen Abfall des 3H-Indexes bei nicht-hormonabhängigen Leberepithelien jugendlicher Ratten kommt es beim Epithel der Samenblasen um den 40. Lebenstag zu einem erneuten, starken Proliferationsschub. Diese starke Wachstumszunahme ist wahrscheinlich der proliferationskinetische Ausdruck der nach Steinberger (1970) zur gleichen Zeit stattfindenden hormonellen Umschaltung in den Testes. Anschließend geht das Vermehrungswachstum des jugendlichen Tieres, durch das die Zellzahl erhöht wird, in das Erhaltungswachstum über; der 3H-Index des Samenblasenepithels erreicht den Wert des erwachsenen Tieres.
    Notes: Summary In 12 male white rats (Wistar) the proliferative activity of the epithelial cells in the seminal vesicles was studied by autoradiography. The animals were 21, 29, 40, 50, 60 and 180 days old. Each animal was given 2.5 μC/g 3H-thymidine and was killed 1 hour thereafter. We analysed the autoradiograms recording the percentage of labelled nuclei (3H-index). While the 3H-index of the non hormone-dependent epithelial cells in the liver of young rats declines continously with growing age (Stocker et al., 1964), the epithelial cells in the seminal vesicles of 40 days old rats show a remarkable rise in their proliferative activity. It is quite possible that this new peak in the proliferation is the morphological result of a preceeding switch in hormonal production of the testes as reported by Steinberger (1970). Thereafter the growth proliferation of the young rats declines into the steady state of the grown up.
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  • 37
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    Cell & tissue research 120 (1971), S. 80-93 
    ISSN: 1432-0878
    Keywords: Tunicate ; Neural gland ; Hypophysial homologue ; Lysosomes ; Ultrastructure ; Phosphatase localization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cells comprising the neural gland in the ascidians Ciona, Styela, and Botryllus have been examined for their fine structural features and enzyme cytochemistry. The gland cells are either cuboidal or irregular in outline. They are full of small vesicles, of which some are pinocytotic, as well as larger vacuoles; they become increasingly vacuolated as their shape decreases in regularity. At the same time, glycogen deposits accumulate and the cisternae of the endoplasmic reticulum become distended. Some of the vacuoles contain an electron dense material or a fibrillar substance, but the cells contain no obvious electron opaque secretory granules associated with an extensive Golgi complex such as occur in the vertebrate adenohypophysis. Acid phosphatase is localized in some of the vesicles and vacuoles, indicating that they are a kind of lysosome, the latter possibly representing autophagic vacuoles. Thiamine pyrophosphatase is also found in many vacuoles as well as in the saccules of the Golgi apparatus which in these cells is in the form of dictyosomes. The results suggest a developmental cycle of increasing cytoplasmic vacuolation, ultimately leading to a breakdown and release of the vacuolar products. The significance of these observations is considered, particularly with respect to the hypothesis that the gland represents the ascidian equivalent of the vertebrate pituitary.
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  • 38
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    Cell & tissue research 119 (1971), S. 334-354 
    ISSN: 1432-0878
    Keywords: Fat absorption ; Small intestine ; Rat ; Micropinocytosis ; Circadian rhythm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die vorliegende Untersuchung will klären, welche Rolle die Mikropinocytose bei der Fettresorption spielt und ob die Fettresorption tagesrhythmische Schwankungen aufweist. Zu diesem Zweck wurde Fett zu verschiedenen Tages- und Nachtzeiten in abgebundene Jejunumabschnitte von Ratten injiziert, das Darmgewebe in verschiedenen Abständen licht- und elektronenmikroskopisch untersucht und die Zahl der mikropinocytotischen Invaginationen der Enterocyten bestimmt. Folgende Resultate wurden erzielt: Die Häufigkeit der Mikropinocytose (mikropinocytotische Invaginationen/100 Mikrovilli) beträgt bei Hungertieren 4,78, bei Normaltieren 5,06, 1 min nach Gabe von Mazolachymus 3,55, 1/16 m NaCl-Lösung 4,37, Butterschmalz 5,50, Rindertalg 7,16, Schweineschmalz 7,66 und Mazola 9,25; 2 1/2 min nach Mazolagabe 8,23, nach 5 min 7,67, nach 10 min 6,76. Zwischen 10 und 15 min wird der Ausgangswert erreicht. Aufgrund statistischer Auswertung der Befunde wird geschlossen, daß Fett vor allem in den Frühstadien der Fettresorption durch Mikropinocytose aufgenommen werden könnte. Ferner zeigt sich, daß die Mikropinocytosehäufigkeit entscheidend von der chemischen Zusammensetzung und dem physikalischchemischen Zustand der verabreichten Fette beeinflußt werden dürfte. — Lichtmikroskopisch wurde nachgewiesen, daß die Fettresorption charakteristische, tagesrhythmische Schwankungen aufweist. Um 2.00 Uhr ist sie am stärksten, um 14.00 Uhr am geringsten. Es wird diskutiert, worauf die tagesrhythmischen Unterschiede zurückzuführen sind.
    Notes: Summary The present study attempts to elucidate (a) to what extent micropinocytosis is involved in the process of fat absorption and (b) whether fat absorption shows a circadian rhythm. For this purpose rats were given 0.1 to 0.15 ml of fat directly into the upper jejunum at various times of the day and night. 20 sec to 20 min after administration of fat small pieces of the jejunum were rapidly dissected out, the tissue examined by means of light- and electron microscopy, and the number of micropinocytotic pits occurring in the enterocytes during fat absorption was determined. The following results were obtained: The frequency of micropinocytosis (micropinocytotic pits/100 microvilli) is as follows: in starved rats 4.78, in normal rats 5.06, 1 min after administration of corn oil chyme 3.55, 1/16 m NaCl-solution 4.37, clarified butter 5.50, ox tallow 7.16, lard 7.66, corn oil 9.25; 2 1/2 min after administration of corn oil 8.23, after 5 min 7.67, and after 10 min 6.76. Between 10 and 15 min the number of micropinocytotic pits reverses to normal. From statistical analysis of the results it is concluded that micropinocytosis can play a significant role in the early stages of fat absorption. The experiments show in addition that micropinocytosis is greatly influenced by the chemical composition and the physico-chemical state of the administered fat.—Light microscopic studies indicate that fat absorption varies considerably during the 24 hr period. The highest absorption was found at 2 a.m., the lowest at 2 p.m.
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  • 39
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    Cell & tissue research 148 (1974), S. 203-211 
    ISSN: 1432-0878
    Keywords: Hypothalamus ; Rat ; Supraoptic nucleus ; Ultrastructure ; Somatic spines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopic studies of ultrathin serial sections of the perikarya and adjacent neuropil of neurons of the supraoptic nucleus (SON) of the adult male rat revealed varying forms of two types of somatic spines. One type forms synapses with axons passing the cell, the other, without synapses, appears to serve as a buttress or clasp for adjacent neuronal and glial processes. The synapse-bearing spines lack the usual spine apparatus but contain the flocculent substance often seen in spines. The other spines do not exhibit either of these structures. These somatic spines were also seen in Golgi impregnated preparations but the types could not be distinguished. Certain axons synapse either on a somatic spine of the perikarya or penetrate the glial sheath of the neuron and synapse, usually repeatedly, on the soma in an en passant manner.
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  • 40
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    Cell & tissue research 148 (1974), S. 371-379 
    ISSN: 1432-0878
    Keywords: Pineal gland ; Rat ; Electric coupling areas ; Freeze-etching
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    Topics: Biology , Medicine
    Notes: Summary The pineal glands of Wistar rats were fixed in glutaraldehyde and prepared by the freeze-etching technique. With regard to the form and internal structure of pineal cells this technique has revealed nothing essentially new. Synaptic ribbons are very rarely found. A regular diagonal arrangement of membrane attached particles between the Schwann cell and the axon of an autonomic nerve terminal was observed. Three types of contact areas between pineal cells are described. In the first two types, which occur more frequently, the diameter of the area varied from 1000 to 2500 Å, with irregularly aggregated membrane associated particles. The third type, larger but less frequently found, has a surface area of 0.4 μm2 and much more regularly distributed membrane associated particles (ø 88 Å). These contact areas can be considered to be electric coupling areas between pineal cells.
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  • 41
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 102-108 
    ISSN: 1618-2650
    Keywords: Zinkstaubdestillation ; Ultramikrobereich, Apparatur, TAS-Verfahren. Thermofraktographie, TAS-Verfahren ; Chromatographie, Dünnschicht ; Zinkstaubdestillation, Ultramikrobereich. Analyse von Naphthalinderivaten, Anthracenderivaten, Phenanthrenderivaten, Tetracenderivaten, Indolderivaten ; Chromatographie, Dünnschicht ; Zinkstaubdestillation, TAS-Verfahren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Methode beschrieben, die es erlaubt, unter kontrollierten Bedingungen mit 20–200 μg Ausgangsmaterial eine Zinkstaubdestillation durchzuführen. Hierzu wird die Probe auf Cu-aktiviertes Zink in einer TAS-Patrone für einige Minuten auf 350–450° C erhitzt. Die dabei entstehenden sauerstofffreien Aromaten bzw. stabilen Heterocyclen werden durch einen Stickstoffstrom von 15 ml/min direkt auf den Startpunkt einer DC-Schicht transferiert. Anschließend wird chromatographiert und die auftretenden Reaktionsprodukte werden identifiziert. Zum Studium der Reaktionsvorgänge und der optimalen Temperaturbereiche dient die Thermofraktographie. Es sind Anwendungsbeispiele aus der Gruppe der Naphthalin-,Anthracen-, Phenanthren-, Tetracen- und Indolderivate gegeben.
    Notes: Abstract A method for zinc dust distillation of 20–200 μg of substance under controlled conditions is described. The sample is heated on copper-activated zinc up to 350–450° C for several minutes in a TAS-cartridge. The resulting oxygen-free aromatic resp. the stable heterocyclic components are transferred directly to the starting point of a TLC-plate by a stream of nitrogen at 15 ml/min and identified after chromatography. Thermography is applied to study the reaction process and to determine the optimal temperature ranges. Examples of application to the groups of naphthalene-, anthracene-, phenanthrene-,tetracene- and indol derivatives are listed.
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 126-127 
    ISSN: 1618-2650
    Keywords: Chromatographie, Dünnschicht ; Rückgewinnung geringer Substanzen
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 119-123 
    ISSN: 1618-2650
    Keywords: Best. von 8-Hydroxychinolinderivaten, 8-Hydroxychinaldinderivaten in Pharmazeut. Produkten ; Chromatographie, Dünnschicht ; ÄDTA-behand. Platten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Methode beschrieben, mit der 8-Hydroxychinolin- und 8-Hydroxychinaldin-Derivate nach erfolgter Entwicklung auf Kieselgelplatten direkt quantitativ mit einem Chromatogramm-Spektralphotometer bestimmt werden können. Durch Vorbehandlung der Platten mit Komplexbildnern, wie Äthylendiamintetraessigsäure, Diäthylentriaminpentaessigsäure oder Triäthylentetraminhexaessigsäure, wird im Gegensatz zur unbehandelten Platte erreicht, daß die Substanzen runde Flecken ausbilden, die zur quantitativen Bestimmung geeignet sind. Die Methode hat sich auch bei der Bestimmung der Wirkstoffe aus Arzneiformen, wie Dragees und Salben, bewährt und läßt sich mit einer maximalen relativen Standardabweichung von ± 3,4% gut reproduzieren.
    Notes: Abstract A method is described allowing direct quantitative determination of 8-hydroxyquinoline and 8-hydroxyquinaldine derivatives with a chromatogram spectrophotometer after development on silicagel plates. In contrast to untreated plates, pretreatment of the plates with complexing agents like ethylene-diamine-tetraacetic acid, diethylenetriamine-pentaacetic acid, or triethylenetetramine-hexaacetic acid, results in formation by the compounds of round areals which are suitable for quantitative measurement. This method proved also valuable for the quantitative measurement of the active contents of pharmaceutical formulations, like tablets or ointments. It is reproducible with a maximal relative standard deviation of ± 3.4%.
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  • 44
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 124-126 
    ISSN: 1618-2650
    Keywords: Trenn. von Pesticiden, phosphorhaltig ; Chromatographie, Dünnschicht ; Schicht aus bas. Zinkcarbonat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Dünnschichten von basischem Zinkcarbonat eignen sich zur Trennung von Insecticiden aus der Gruppe der Organophosphorsäuren. Mit Petroläther/Aceton-Gemischen zwischen 98∶2–86∶14 werden günstige Rf-Werte und gute Fleckzeichnungen erreicht. Die Substanzen sind entweder im kurzwelligen UV-Licht zu erkennen, wenn man der Dünnschicht Fluorescenz-Indicator F 254 der Fa. Merck zusetzt, oder aber im Tageslicht nach Sprühen mit Pd(II)Cl2-Lösung, wobei rotbraune Flecken entstehen. Die Wirkstoffe lassen sich mit Aceton quantitativ eluieren; Die Trennung kann auch säulen-chromatographisch durchgeführt werden. Die Trenneffekte sind ähnlich denjenigen, wie sie auf Kieselgel erreicht werden. Das basische Zinkcarbonat hat aber den Vorteil geringerer chemischer Aktivität, so daß weniger Artefakte entstehen.
    Notes: Abstract Thin layers of basic zinc carbonate can be used with good results to separate organophosphorous pesticides. With a petroleumether/acetone mixture (between 98∶2 and 86∶14) good Rf-values and clearly defined spots are obtained. The substances are either recognizable in short-wave UV-light, when the fluorescence indicator F 254 from Fa. Merck is added to the thin layer, or in day-light, after having been sprayed with a solution of Pd(II)Cl2, which leads to the formation of reddish-brown spots. The pesticides can be eluted quantitatively with acetone; the separation can also be carried out by means of column chromatography. The effects of separation are similar to those obtained on silica gel, but basic zinc carbonate has the advantage of lower chemical activity, which means that less artifacts are formed.
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 125-126 
    ISSN: 1618-2650
    Keywords: Nachw. von Xylenolen, Dimethylphenolen ; Chromatographie, Dünnschicht ; versch. Schichten u. Reagentien
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  • 46
    ISSN: 1618-2650
    Keywords: Nachw. von Kresolen, Phenol ; Chromatographie, Dünnschicht ; versch. Schichten und Reagentien
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  • 47
    ISSN: 1432-0878
    Keywords: Substantia nigra ; Rat ; Incorparation of 3H-Dopamine, 3H-Serotonin and 3H-Norepinephrine ; Axo-dendritic Synapses ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In autoradiographies of substantia nigra in rat, it has been observed that after intraventricular injections of 3H-dopamine and 3H-norepinephrine respectively the silvergrains are accumulated in nigra neurons and their dendritic branches. The incorporation was more pronounced in the case of 3H-norepinephrine than 3H-dopamine. This seems to indicate that exogenous norepinephrine may have stronger affinity to nigra neurons and their dendrites than exogenous dopamine. In addition, some 3H-dopamine and 3H-norepinephrine labelled nerve terminals were observed in axo-dendritic synapses. In contrast to these data, 3H-5HTP and 3H-5HT administration showed almost all silver grains accumulated in the neuropil when observed in light microscopic autoradiography. Electron micrographs further reveal that the incorporation of 3H-5HTP and 3H-5HT was mostly within axo-dendritic boutons with more frequent dense core vesicles. These data again strongly suggest that substantia nigra receives a large number of serotoninergic fibres forming axo-dendritic synapses which may play an important role in modulation of substantia nigra function.
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  • 48
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    Cell & tissue research 114 (1971), S. 271-280 
    ISSN: 1432-0878
    Keywords: Thymus ; Rat ; Involution ; Reticulum-Cells ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Entodermale Thymus-Retikulumzellen neugeborener Wistar-Ratten enthalten häufig helle Vesikel mit enger räumlicher Beziehung zum Golgi-Apparat. Bei 13 Monate alten Ratten fehlen diese Vesikel. 2. Die Tatsache, daß die Häufigkeit heller Vesikel mit fortschreitendem Lebensalter abnimmt, findet ihre Parallele in der von anderer Seite getroffenen Feststellung, daß die Bildung eines humoralen Faktors im Thymus im Laufe der Zeit eingeschränkt wird. 3. Diese Koinzidenz läßt an die Möglichkeit denken, die hellen Vesikel könnten ein morphologisches Äquivalent der Bildung eines Thymuswirkstoffes sein. 4. In entodermalen Thymus-Retikulumzellen 13 Monate alter Ratten finden sich große Vakuolen mit granulärem Inhalt. Ihre Bildung beginnt schon vor der Thymusinvolution. Sie entstehen wahrscheinlich durch Phagozytose oder Aufnahme zelleigenen Materials, das nicht weiter abbaufähig ist. 5. Da diese Einschlüsse mit fortgesetzem Alter an Zahl und Größe zunehmen, scheinen sie als Ausdruck einer Beeinträchtigung der Stoffwechselvorgänge im Zytoplasma ein erstes morphologisch faßbares Symptom der frühzeitigen physiologischen Involution des Thymus zu sein.
    Notes: Summary 1. Entodermal reticulum cells of new born Wistar rats frequently contain clear vesicles with close connection to the Golgifield. These vesicles do not occur in reticulum cells of 13 months old rats. 2. The frequency of these clear vesicles decreases with advancing age obviously in the same way as the production of a humoral thymic factor reported by several investigators. 3. This observation agrees with the hypothesis that the clear vesicles are the morphological equivalent of the production of a humoral thymus factor. 4. Entodermal reticulum cells of 13 months old Wistar rats contain large vacuoles filled with electron dense, granulated materials. The formation of these vacuoles starts already before the beginning of the thymus involution. Possibly they are produced by phagocytosis or necrobiosis and contain deposits of material that cannot undergo further degradation. 5. The increase of these vacuoles in number and size with advancing age may be considered as equivalent of the deterioration of metabolism responsible for early involution of the thymus.
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  • 49
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    Cell & tissue research 116 (1971), S. 61-69 
    ISSN: 1432-0878
    Keywords: Paraventricular nucleus ; Rat ; Types of neurons ; TRF-synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural aspects of the paraventricular nucleus and its neuropil are described in the normal rat. Two types of neurons can be distinguished morphologically. The first type contains numerous dense-core vesicles (mean diameter: 140 nm). The cisternae of the endoplasmic reticulum are arranged parallely at the periphery of the cell body. The second type of neuron contains a few dense-core vesicles (mean diameter: 75 nm) and the endoplasmic reticulum is randomly distributed in the cytoplasm. In the neuropil, two types of dense-core vesicles are observed in separated axons. The histogram of the distribution of their mean diameter clearly indicates a double population of vesicles. The signification of the second type of neuron in the paraventricular nucleus is discussed and its possible relation to TRF synthesis is evoked.
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  • 50
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    Cell & tissue research 116 (1971), S. 119-135 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex difference ; Light microscopy ; Histometry
    Source: Springer Online Journal Archives 1860-2000
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    Description / Table of Contents: Zusammenfassung An 260 männlichen und weiblichen Sprague-Daweley-Ratten vom 0. Lebenstag bis zur 12. Lebenswoche wird die geschlechtsdifferente Entwicklung der Nebennierenrinde histologisch und histometrisch verfolgt. Von der 4. Lebenswoche an ist die weibliche Fasciculatazelle durch ein helles, fein-granuläres Cytoplasma ohne distinkt abgrenzbare Fettvakuolen ausgezeichnet, während beim Männchen in einem kompakten Cytoplasma zunehmend größere, deutlich begrenzte Vakuolen auftreten. Im Blindversuch gelingt aufgrund dieser Kriterien die Geschlechtsdiagnose mit großer Treffsicherheit. Nach histometrischen Untersuchungen sind die weiblichen Fasciculatakerne größer als die männlichen. Bei größerem Zellvolumen ist die Kernzahl/Flächeneinheit beim Weibchen von der Pubertät an kleiner. Die Glomerulosa und die inneren Rindenschichten zeigen keine Geschlechtsdifferenzen. Fermenthistochemisch ist eine Geschlechtsdifferenz nicht nachweisbar. Die relative Zellhypertrophie in der Fasciculata der weiblichen Nebennierenrinde ist das morphologische Äquivalent eines geschlechtsdifferenten Steroidmetabolismus bei der Ratte.
    Notes: Summary In 260 male and female Sprague-Dawley CD rats the sex dependent development of the adrenal cortex was studied histologically and by histometric procedures. Beginning in the 4th week of life the parenchymal cells in the fasciculata of the female animals are characterized by a light, finely granular cytoplasm without distinct lipid vacuoles. In the males, however, the cells show a dense, compact cytoplasm with clearly visible vacuoles increasing in size. In a blind test the sex diagnosis can be established with great accuracy. Histometrically the nuclei in the female fasciculata cells are larger than in the males. Furthermore, caused by a larger cell volume the number of nuclei per square unit is smaller in postpuberal females. The glomerulosa and the inner parts of the cortex do not show any sex differences, nor does enzyme histochemistry. The relative cellular hypertrophy in the fasciculata of the female adrenal cortex represents the morphologic equivalent of the sexual differences in the rats steroid metabolism.
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  • 51
    ISSN: 1432-0878
    Keywords: Nematosomes ; Subsynaptic web ; Microfilamentous cytoplasmic network ; Neurosecretory cells ; Rat
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    Notes: Summary An electron microscope study of the rat supraoptic nucleus, substantia nigra, neostriatum and periventricular preoptic area demonstrates that nematosomes are present within the perikaryon of neurons located in these structures. The latter structure may be found in close association with the subsynaptic web of axosomatic synapses. Numerous micro-filaments fan out from the nematosome and link the latter organelle to the ribosomes, the cytoplasmic membranes and the plasma membrane thus establishing an interwoven filamentous cytoplasmic network. A possible close relationship between the nematosomes and the neurofilaments and neurotubules is discussed.
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    Cell & tissue research 118 (1971), S. 243-248 
    ISSN: 1432-0878
    Keywords: Arteriovenous anastomoses ; Valve mechanism ; Rat ; Skin of the paw
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    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung In der dorsalen Haut der Hinterpfoten von Ratten wurden Klappen am Abgang kleinerer Gefäße von großen Arterien beobachtet. Diese Arterien verlaufen in einer subkutanen, größere Gefäße und Nerven führenden Bindegewebsschichte über den Streckersehnen. Die kleineren Gefäße haben den Wandbau einer Vene und zweigen etwa im rechten Winkel von der Arterie ab. An ihrer Abgangsstelle ist neben den Klappen manchmal ein sphinkterartiger Muskelring ausgebildet. Diese Gefäßabschnitte werden für arterio-venöse Anastomosen gehalten und auf die Bedeutung solcher an dieser Stelle bisher nicht beschriebenen Verschlußeinrichtungen für die Regulation der Kurzschlüsse wird hingewiesen.
    Notes: Summary In the dorsal skin of the hindpaws of rats valves were observed at those sites where smaller vessels branched from larger arteries. These arteries run in a subcutaneous layer of connective tissue, which lies above the extensor tendons and in which the larger vessels and nerves are found. These smaller vessels, the walls of which resemble those of veins, were seen branching off at approximate right angles to their artery of origin. Besides the valves a sphincterlike muscle ring was observed in some cases at the point of branching. These vascular segments are held to be arteriovenous anastomoses. Such “locking devices” at these points have not been described until now and seem to be important in the regulation of arteriovenous shunts.
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    Cell & tissue research 121 (1971), S. 171-180 
    ISSN: 1432-0878
    Keywords: Nerve endings ; Epithelium ; Rat ; Electronmicroscopy
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    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Im Anschluß an frühere lichtmikroskopisch erhobene Befunde (Silberimprägnation; 1924, 1928) weist der Verfasser durch elektronenmikroskopische Untersuchungen nach, daß durch die Interzellularspalten des Epithels (Schnauze der weißen Ratte) Nervenfasern hindurchziehen. Diese Nervenfäserchen, ihre Varikositäten und ihre Endknöpfchen liegen in den Spalten zwischen den Epithelzellen. Die Ultrastruktur der nackten, d.h. von Schwannschen Zellen nicht umhüllten terminalen Nervenfasern und ihrer Endigungen im Epithel wird beschrieben.
    Notes: Summary In addition to former light microscopical observations the author demonstrates electronmicroscopically that nerve fibers pass through the intercellular spaces of the epithelium. The nerve fibers, their varicosities and terminal bulbs lie within the spaces between the epithelial cells. The ultrastructure of the terminal nerve fibers in the epithelium is described.
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    Cell & tissue research 121 (1971), S. 292-300 
    ISSN: 1432-0878
    Keywords: Tissue Mast Cells ; Rat ; Regeneration ; Monocytes ; Peritoneal Exudates ; Cytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Regeneration von Gewebsmastzellen wurde durch Untersuchungen von Peritonealexsudat erwachsener Ratten verfolgt, die häufigen Spülungen der Bauchhöhle unterworfen wurden. Innerhalb von 4–6 Tagen kommt es zu einer starken Vermehrung unreifer Gewebszellen. Die Ausbildung von Alcianblau-positiven unreifen Granula in ungranulierten Vorstufen benötigt etwa 6 Std. Die Ausbildung von Safranin-positiven reifen Granula vollzieht sich in 48 Std. Die Ergebnisse der zytochemischen Untersuchungen unreifer Mastzellvorstufen sprechen für eine monozytogene Entstehung der Gewebsmastzellen.
    Notes: Summary In adult rats, the regeneration of tissue mast cells in peritoneal exudates was studied by repeated peritoneal lavages. After 4–6 days, tissue mast cells appeared in great numbers in peritoneal exudates. Alcian blue positive granules were first noted at 6 hrs in agranular mast cell precursors. Maturation with accumulation of safraninpositive granules was complete after 48 hrs. The cytochemical reactions of the earliest tissue mast cell precursors suggest a monocytogenic origin of tissue mast cells.
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    Cell & tissue research 147 (1974), S. 285-292 
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Serotonin terminals ; 5,6- and 5,7-Dihydroxytryptamine ; Chemical degeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopical evidence for the existence of an important serotonergic input to the rat median eminence is presented. This evidence is based on the demonstration of degenerating nerve terminals in the external layer of the rat median eminence following the application of 5,6-dihydroxytryptamine or 5,7-dihydroxytryptamine, drugs known to exert more or less selective toxic effects on central serotonin neurons. The finding of a serotonergic innervation of the median eminence in mammals has important implications for 5-hydroxytryptamine as a modulator of synthesis and/or release of hypothalamic, hypophysiotropic hormones.
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    Cell & tissue research 147 (1974), S. 219-235 
    ISSN: 1432-0878
    Keywords: Lysosomes ; Mouse fibroblasts ; Dye treatment ; Cell culture ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mouse fibroblasts were grown in a ‘deficient’ medium consisting solely of Hank's salt solution. Treatment of cells after 48 hours in deficient medium with the cationic dye, mepacrine, resulted in an altered formation of lysosomes. Cells grown in full medium form dense, multi-vesiculated lysosomes in response to mepacrine. Cells grown in deficient medium form large electron lucent vacuoles containing peripherally located dense globules. The significance of the observations in relation to the deficiency of the medium is discussed.
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    Cell & tissue research 149 (1974), S. 91-104 
    ISSN: 1432-0878
    Keywords: Anococcygeal muscle ; Smooth muscle ; Rat ; Innervation, adrenergic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The rat anococcygeus muscle, which is known from previous functional and histochemical investigations to be a smooth muscle with a dense adrenergic innervation, was studied by electron microscopic methods. The muscle was found to be organized in small bundles of 2 to 8 muscle cells, which were interconnected by desmosome-like junctions and by gap junctions. Small Schwann cell-axon complexes with 1 to 5 axons appeared to represent the functional terminal nerve pathway. Such axon complexes were located at the periphery of the small smooth muscle bundles, they never penetrated into them. A ratio of approximately 6 small axon complexes per 100 muscle cells was found. After glutaraldehyde fixation axon varicosities contained mainly small empty vesicles. After treatment with 5-hydroxydopamine and permanganate fixation mainly small vesicles with a dense core were found. The neuromuscular distances ranged from 550 to 5000 Å, with a mean of about 2600 Å. True close neuromuscular contacts at a distance below 500 Å with a fusing of basal laminae were absent. The present observations provide a morphological base for the findings of previous electrophysiological and pharmacological studies on the anococcygeal muscle.
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  • 58
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    Cell & tissue research 149 (1974), S. 113-120 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex-hormones ; Ultramorphometry
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    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Ultramorphometrisch wurde nach dem Verfahren von Rohr et al. (1971) die äußere Zona fasciculata von Sprague-Dawley-Ratten bei 5 Gruppen zu je 4 Tieren verglichen: Männchen, Weibchen im Diöstrus, Weibchen im Östrus, männliche und weibliche Kastraten (Kastration am 4. Lebenstag). Die Nebennierenrindenzellen der äu\eren Fasciculata sind bei Weibchen gegenüber denen normaler Männchen hypertroph: Weibchen im Diöstrus zeigen gegenüber Männchen größere Einzelzellen mit vermehrtem glattem endoplasmatischem Reticulum, erhöhten Einzel- und Gesamtvolumina der Mitochondrien sowie einem höheren Lipoidgehalt bei stärkerer Dispersion der Liposomen. Dieselben funktionsspezifischen Strukturen nehmen bei den Weibchen im Östrus noch weiter zu. Die Kastration der Weibchen am 4. Lebenstag führt zu einer Reduktion der funktionsspezifischen morphometrischen Parameter unter die Werte der Diöstrus-Tiere. Männliche Kastraten gleichen die Werte ihrer funktionsspezifischen Strukturen weitgehend denen der Weibchen im Diöstrus an. Nach Kastration am 4. Lebenstag zeigen weibliche Tiere somit etwas niedrigere morphonietrische Parameter in der äußeren Zona fasciculata als die männlichen Kastraten.
    Notes: Summary With the method of Rohr et al. (1971) the outer zona fasciculata of Sprague-Dawley-rats was compared ultramorphometrically in 5 groups of 4 animals each: males, females during diestrus, females during estrus, male and female castrates (castration on 4th day of life). Adrenal cortical cells of the outer fasciculata in females are hypertrophic in comparison with those of normal males: females during diestrus show in comparison with males larger individual cells with increased SER, increased volume of the individual mitochondrium and total volume of mitochondria as well as an increased lipoid content together with a more pronounced dispersion of liposomes. The same function-specific structures show a further increase in females during estrus. Castration of females on the 4th day of life leads to a reduction of the function-specific morphometric parameters below the values of the diestrus animals. Male castrates show adaption of the values of their function-specific structures towards those of females during diestrus. Following castration on the 4th day of life, female animals thus show somewhat lower morphometric parameters in the outer zona fasciculata than male castrates.
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    Cell & tissue research 149 (1974), S. 235-243 
    ISSN: 1432-0878
    Keywords: Adrenal zona glomerulosa ; Rat ; Normal ; Electron microscopy
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    Topics: Biology , Medicine
    Notes: Summary This paper reports on an electron microscopic study of the adrenal zona glomerulosa in the normal rat, with special emphasis on the structural diversity of mitochondria in its parenchymatous cells. The mitochondria of cristae may be tubulo-vesicular, plate-like and/or straight tubular, any one mitochondrion containing one or more types of cristae. The mitochondrial features of the zona glomerulosa parenchymatous cells are attributed to the biochemical stages of aldosterone synthesis, taking place in different mitochondria of these cells.
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  • 60
    ISSN: 1432-0878
    Keywords: Hypothalamo-neurohypophysial system ; Rat ; Granule distribution ; Electron microscopy, morphometry
    Source: Springer Online Journal Archives 1860-2000
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    Description / Table of Contents: Zusammenfassung Die Neurohypophyse und die neurosekretorischen hypothalamischen Kerngebiete von normalen männlichen und weiblichen Ratten, von trächtigen und durstenden Tieren wurden elektronenmikroskopisch und morphometrisch mit der Fragestellung untersucht, ob sich in den Häufigkeitsverteilungen der mittleren Granula-Durchmesser, bezogen auf die Anzahl der Axone, eine zweigipflige Verteilung ergibt. Bei Kontrolltieren zeigen die Perikarya des Nucleus supraopticus zahlreichere und größere Granula als die Zellen des Nucleus paraventricularis, wobei der Unterschied in den Durchmessern der Granula bei den weiblichen Tieren ausgeprägter ist als bei den männlichen. Beide Kontrollgruppen zeigen in der Neurohypophyse ein zweigipfliges Verteilungsmuster der Granula, wobei die beiden Gipfel bei den männlichen Kontrollen dichter beieinander liegen als bei den weiblichen. Bei den trächtigen Tieren weisen beide Kerngebiete Zeichen gesteigerter Aktivität auf und die Granula in den Zellen des Nucleus paraventricularis sind deutlich größer als bei Kontrolltieren. Zu Beginn der Tragzeit werden relativ große, wahrscheinlich vasopressinhaltige Granula in der Neurohypophyse gespeichert, während sich im letzten Drittel der Tragezeit die beiden Populationen dort nicht mehr unterscheiden lassen. Nach 48 Std. Wasserentzug erscheinen beide hypothalamischen Kerne aktiviert. Auffallend ist, daß die Granula im Nucleus supraopticus deutlich kleiner sind als bei Kontrolltieren. Entsprechend fehlen in der Neurohypophyse große Granula, während Axone mit kleinen Granula vermehrt sind. Nach zehntägiger Durstperiode lassen sich im Nucleus supraopticus, neben sehr typischen morphologischen Veränderungen, morphometrisch ebenfalls deutlich kleinere Granula nachweisen. Im Hypophysenhinterlappen dieser Versuchsgruppe sind die granulahaltigen Axone sehr stark vermindert, und in der Häufigkeitsverteilung fehlen die Granula mit großem Durchmesser während der dem Oxytocin zugeordnete Gipfel unverändert erscheint. In Verbindung mit den elektronenmikroskopischen Befunden lassen sich also aus den Verschiebungen der Verteilungsmuster zwischen den sechs Versuchsgruppen die Granula mit kleinerem Durchmesser oxytocinhaltigen Axonen zuordnen und Granula mit größerem Durchmesser zu den Endigungen, die Vasopressin enthalten. Die morphometrischen Befunde in den neurosekretorischen hypothalamischen Kerngebieten bestätigen diese Zuordnung. Die elektronenmikroskopischen und morphometrischen Befunde werden besonders im Hinblick auf die Hormonverschiebungen zwischen dem “reserve pool” und den “easily releasable pool” diskutiert.
    Notes: Summary A morphometric evaluation of electron micrographs has been carried out from neurosecretory terminals in the neurohypophysis and from the supraoptic and paraventricular nuclei in normal male and female rats as well as in pregnant and water deprived rats. The task of this investigation was to find out whether frequency distribution diagrams of the mean diameter of the neurosecretory granules, plotted versus the number of axons, reveal a grossly bimodal distribution. In normal rats the nerve cells of the nucleus supraopticus (S.O.N.) show more numerous and larger granules than the cells of the nucleus paraventricularis (P.V.N), this difference with respect to the diameter being more pronounced in female than in male animals. In the posterior pituitary lobes the neurosecretory granules exhibit a bimodal distribution, the second peak being situated more closely to the first one in male controls. In pregnant animals both nuclei appear to be activated, and the granules of P.V.N. are distinctly larger as compared to those of female control animals. In early pregnancy larger, i.e. presumably vasopressin-containing granules are stored in the neurohypophysis, while in the last phase before delivery oxytocin-containing neurons and vasopressin-containing ones cannot be differentiated any more. After 48 hrs of thirst both hypothalamic nuclei exhibit signs of increased activation, the diameters of the granules in the S.O.N. being distinctly smaller than in normals. In the neurohypophysis granules with large diameters are lacking, while axons with small granules are more frequent. In the S.O.N. of animals, water deprived for 10 days the diameters of the granules are smaller than normal and in the neurohypophysis the number of granule-containing fibres is strongly reduced. In the frequency distribution diagram granules with larger diameters are lacking whereas the peak, attributed to oxytocin, is not essentially altered. However, from the observed alteration on the distribution patterns of the six experimental groups and in connection with the electron microscopic results the granules with smaller diameters can be attributed to oxytocin-containing axons and the larger ones to vasopressin-containing terminals. Analogous morphometric data have been obtained from the neurosecretory nuclei as well. The electron-microscopic and morphometric observations are discussed with regard to hormone-shifts between the reserve pool and the easily-releasable pool.
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    Cell & tissue research 151 (1974), S. 471-480 
    ISSN: 1432-0878
    Keywords: Juxtaglomerular apparatus ; Rat ; Influence of deoxycorticosterone (DOC) ; Electron microscopy ; Morphometric analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: 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.
    Notes: 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.
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 203-205 
    ISSN: 1618-2650
    Keywords: Strukturaufklärung von Sesquiterpenalkoholen ; TAS-Verfahren, Mikrodehydrierung ; Chromatographie, Dünnschicht ; bicyclisch, mit Decalin-Grundgerüst
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Aus dem ätherischen Öl der Haselwurz wurden erstmalig die 4 Sesquiterpenalkohole α-Eudesmol, β-Eudesmol, Selinan-7,11-diol und Selin-6(7)en-11-ol isoliert und identifiziert. Dabei wurde zur Einengung der Strukturmöglichkeiten die dehydrierende TAS-Methode (Schwefel-Dehydrierung) eingesetzt. Sie lieferte bei ungesättigten C15-Alkoholen gute Ergebnisse. Gesättigte Sesquiterpenalkohole mit Decalin-Grundgerüst ließen sich besser nach der Selenmethode dehydrieren. Von den entstandenen Naphthalin-Derivaten wurden die UV-Spektren direkt von der DC-Platte aufgenommen und zur Identifizierung herangezogen. Durch diese Kombination der Mikroverfahren konnte das Grundgerüst der Alkohole mit Mikrogramm-Mengen eindeutig bestimmt werden.
    Notes: Abstract In the essential oil of Asarum europaeum L. the four sesquiterpene alcohols α-eudesmol, β-eudesmol, selinane-7,11-diol and seline-6(7)en-11-ol have been isolated and identified. For limiting the possibilities of structure the dehydrogenating TAS method (sulphur dehydrogenation) has been employed. Good results have been obtained with unsaturated C15-alcohols. Saturated sesquiterpene alcohols with decalin structure could be better dehydrogenated by the selenium method. UV spectra have been recorded of the naphthalene derivatives formed directly from the thin-layer plate and employed for identification. By this combination of micro methods the basic structure of the alcohols could be determined unequivocally with μg amounts.
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  • 63
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 337-342 
    ISSN: 1618-2650
    Keywords: Analyse der Metallchelate von o,o′-Dihydroxyazoverbindungen ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung In einer früheren Veröffentlichung [4] ist auf die Möglichkeit der chromatographischen Trennung strukturisomerer Metallchelate hingewiesen worden; sie soll hier ausführlicher dargestellt werden. Weiterhin wird die Trennung von 1:2-Mischkomplexen von Azofarbstoffen und von 1:2-Metallkomplex-Mischungen durch Dünnschicht-Chromatographie (DC) an Polyamid beschrieben. Unter bestimmten Voraussetzungen kann durch DC an Kieselgel zwischen 1:2-Metallkomplexfarbstoffen mit Sulfonsäureamid- bzw. Alkylsulfongruppen und solchen ohne diese Substituenten unterschieden werden. Die beschriebenen DC-Methoden ermöglichen bei richtiger Interpretation eine eindeutige Unterscheidung zwischen strukturisomeren Metallkomplexen der 1:1- und 1:2-Reihe, sowie Mischkomplexen und Komplexmischungen vom 1:2-Metall-chelattyp unsulfierter o,o′-Dihydroxyazoverbindungen. Symmetrische o,o′-Dihydroxyazoverbindungen, wie z.B. das 2,2′-Dihydroxy-5,5′-dimethyl-azobenzol(7), sind geeignete Komplexbildner für Schwermetallkationen, um diese als farbige Chelate mit Hilfe der DC voneinander zu trennen. Strukturisomere sind wegen der Molekülsymmetrie ausgeschlossen, so daß die Ergebnisse eindeutig sind.
    Notes: Abstract In an earlier publication [4] the possibility of the Chromatographic separation of structurally isomeric metal chelates was mentioned; this is dealt with here in more detail. Further the separation of 1:2 mixed complexes from azo dyes and 1:2 metal-complex mixtures by thin-layer chromatography (TLC) on polyamide is described. In certain circumstances it is possible to distinguish between 1:2 metal-complex dyes with sulphonamide or alkylsulphonyl groups and those without these substituents by TLC on silica gel. The TCL methods described allow-when correctly interpreted-an unambiguous distinction between structurally isomeric metal complexes of the 1:1 and 1:2 series, and mixed complexes and mixtures of complexes of the 1:2 metal-chelate type of unsulphonated o,o′-dihydroxyazo compounds. Symmetrical o,o′-dihydroxyazo compounds, such as 2,2′-dihydroxy-5,5′-dimethylazobenzene(7), are suitable as complex-formers for heavy-metal ions, allowing the separation of the latter as their coloured chelates with aid of TLC. Structural isomers are excluded because of the molecular symmetry, so that the results are unambiguous.
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 10-15 
    ISSN: 1618-2650
    Keywords: Chromatographie, Dünnschicht ; Vergleich von Zweistrahldensitometern
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Zur Eliminierung von Störungen der quantitativen Auswertung von Dünnschicht-Chromatogrammen durch Unregelmäßigkeiten der Sorptionsschicht werden öfters Zweistrahlgeräte verwendet. Diese Arbeit berichtet über die Simulation verschiedener Zweistrahlgeräte auf einem Einstrahlgerät mit Hilfe von Digitalrechnern, um auf diesem Wege eindeutige Aussagen über den Genauigkeitsgewinn treffen zu können. Die relativen genäherten Standardabweichungen aus einer größeren Anzahl von Messungen ergaben folgende Werte: Einstrahlgerät 3–5%, Zweistrahlgerät 2–4% und Zweiwellenlängengerät 2,5–4%.
    Notes: Abstract To avoid errors caused by irregularities of chromatoplates in quantitative TLC often double beam densitometers are used. This paper describes the simulation of different double beam instruments using a single beam scanner and digital computers, to obtain distinct data on the increase in accuracy. The relative standard deviations from a greater number of experiments are: single beam scanner 3–5%, double beam instrument 2–4% and dual wave-length scanner 2.5–4%.
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  • 65
    ISSN: 1618-2650
    Keywords: Best. von Toluidinen ; Chromatographie, Dünnschicht ; diazidodisulfostilbenimprägnierte Schichten
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 177-181 
    ISSN: 1618-2650
    Keywords: Untersuchung der Autoxidation von Fettsäureestern ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Mittels Dünnschicht-Chromatographie kann man den Ablauf von Autoxidationsprozessen an Lipiden qualitativ anhand der auftretenden Reaktionsprodukte verfolgen. In vorliegender Arbeit wurden verschiedene Laufmittel auf Silicagel hinsichtlich ihres Trennvermögens für Gruppen von Autoxidations-produkten erprobt. Ferner werden aufgrund umfangreicher Untersuchungen Sprühmittel zur Erkennung solcher Stoffgruppen auf dem Dünnschicht-Chromatogramm benannt. Am Beispiel der Autoxidation von c-9-Octadecensäuremethylester ohne und mit Zusatz von DDE wird die Leistungsfähigkeit der beschriebenen Arbeitsweise belegt.
    Notes: Abstract The autoxidation of lipids has been followed qualitatively by means of the reaction products. The separating ability of different solvents on silica gel for groups of autoxidation products has been tested. Furthermore, spraying agents for the detection of these groups on the chromatogram are given. The autoxidation of c-9-octadecenic methyl ester with and without addition of DDE serves as an example for the efficiency of the method.
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 257-264 
    ISSN: 1618-2650
    Keywords: Schwefeldehydrierung, Selendehydrierung ; Ultramikrobereich, Apparatur, TAS-Verfahren. Thermofraktographie/TAS-Verfahren/Chromatographie, Dünnschicht ; Schwefel- und Selendehydrierung, Ultramikrobereich. Analyse von Sesquiterpenderivaten, Abietinsäure. Steroiden ; Chromatographie, Dünnschicht ; Schwefel- und Selendehydrierung, TAS-Verfahren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Schnellmethode beschrieben, die es erlaubt, unter kontrollierten Bedingungen mit 50–300 μg Ausgangsmaterial eine gekoppelte Dehydratisierung und Schwefel- bzw. Selendehydrierung durchzuführen. Hierbei wird die Probe mit einer Kaliumhydrogensulfat-Schwefel- bzw. Selenmischung für einige Minuten bei vorbestimmten Temperaturen zwischen 160–400° C im TAS-Ofen bzw. Tasomat erhitzt. Die entstehenden Aromaten werden durch einen Stickstoffstrom von 10 ml/min direkt auf den Startpunkt einer DC-Schicht transferiert. Anschließend wird chromatographiert und die auftretenden Reaktionsprodukte werden identifiziert. Zum Studium der Reaktionsvorgänge und der optimalen Temperaturbereiche dient die Thermofraktographie. Es sind Anwendungsbeispiele aus der Sesquiterpen-, Diterpen- und aus der Steroidreihe gegeben.
    Notes: Abstract A rapid method is described which permits to carry out a coupled dehydratization and sulphur resp. selenium dehydrogenation with 50–300 μg of starting material under controlled conditions. The sample is heated on a potassium hydrogen sulphate-sulphur resp. selenium mixture at preselected temperatures of between 160–400° C for several minutes in the TAS-oven resp. the Tasomat. The resulting aromatic components are transferred directly to the starting point of a TLC-plate by a stream of nitrogen at 10 ml/min and the reaction products are identified after chromatography. Thermofractography is applied to study the reaction processes and to determine the optical temperature ranges. Examples of application to the groups of sesquiterpenes, diterpenes and steroids are listed.
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 285-286 
    ISSN: 1618-2650
    Keywords: Nachw. von Canthaxanthin in Biolog. Material ; Chromatographie, Dünnschicht ; Fertigfolien UV 254
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  • 69
    ISSN: 1618-2650
    Keywords: Best. von Kresolen, Phenol, Xylenolen, Dimethylphenolen ; Chromatographie, Dünnschicht ; imprägn. Fertigfolien u. Kieselgel, Nachweisgrenzen
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 337-340 
    ISSN: 1618-2650
    Keywords: Abtrenn. des 2,4-Dinitrophenylhydrazons von Formaldehyd, Acetaldehyd, Acrolein, Crotonaldehyd, Furfurol ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird ein dünnschicht-chromatographisches Verfahren zur Trennung von Formaldehyd, Acetaldehyd, Furfurol, Acrolein und Crotonaldehyd in Form der 2,4-Dinitrophenylhydrazone beschrieben. Die Derivate werden aus Pyridin, Tetrahydrofuran oder Dioxan aufgetragen und innerhalb von 6 h nach der Durchlauftechnik an Kieselgel F 254-Rapidplatten mit Tetrachlorkohlenstoff/Pyridin (90∶10) aufsteigend entwickelt. Die Laufstrecken verhalten sich wie 1∶1,3∶1,7∶2,1∶2,3.
    Notes: Abstract The derivatives are applied on rapid plates silica gel F 254 from pyridine, tetrahydrofuran or dioxan solution and separated during 6 h by ascending overrun development using carbon tetrachloride/pyridine (90∶10) as a solvent. The distances travelled from the starting point are in the ratio 1∶1.3∶1.7∶2.1∶2.3.
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 365-366 
    ISSN: 1618-2650
    Keywords: Turigeran, Multivitaminpräparate ; Chromatographie, Dünnschicht ; Fertigfolien
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 271 (1974), S. 367-368 
    ISSN: 1618-2650
    Keywords: Uran(VI) ; Chromatographie, Dünnschicht ; DEAE-Cellulose, Phosphorsäure
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 206-206 
    ISSN: 1618-2650
    Keywords: Nachw. von Diphenyl ; Chromatographie, Dünnschicht ; verschiedene Reagentien u. Schichten
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    Topics: Chemistry and Pharmacology
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  • 74
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 286-286 
    ISSN: 1618-2650
    Keywords: Nachweis von Herbiciden, Pesticiden ; Chromatographie, Dünnschicht ; Fertigfolien, Nachweisgrenzen
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    Topics: Chemistry and Pharmacology
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  • 75
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    Fresenius' Zeitschrift für analytische Chemie 272 (1974), S. 368-368 
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    Keywords: Best. von DDT in Eiern ; Chromatographie, Dünnschicht
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 128-128 
    ISSN: 1618-2650
    Keywords: Nachw. von Alkoholen als Co-Xanthate ; Chromatographie, Dünnschicht
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 272-274 
    ISSN: 1618-2650
    Keywords: Best. von Gramicidin ; Chromatographie, Dünnschicht ; CAMAG Eluchrom
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Eine quantitative Methode zur Bestimmung von Gramicidin in Fermentationsproben, Extraktionslösungen und Tyrothricin- bzw. Gramicidin-Fertigprodukten wird beschrieben. Nach der dünnschicht-chromatographischen Trennung des Gramicidins von den Begleitstoffen erfolgt eine quantitative Elution des Fleckes mit dem CAMAC Eluchrom, die so gewonnenen Lösungen werden spektralphotometrisch ausgewertet.
    Notes: Abstract A quantitative method is described for the determination of gramicidine in fermentation broths, extracts and finished products of tyrothricine and gramicidine, respectively. After TLC-separation of gramicidine from accompanying substances a quantitative elution of the gramicidine spot is performed with the CAMAG Eluchrom. The solutions obtained are measured spectrophotometrically.
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    Fresenius' Zeitschrift für analytische Chemie 268 (1974), S. 268-272 
    ISSN: 1618-2650
    Keywords: Chromatographie, Dünnschicht ; Peakerkennung u. Auswertung mit Digitalrechnern
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Arbeit beschreibt den prinzipiellen Aufbau eines Programms für Digitalrechner zur numerischen Peakerkennung und numerischen Integration von Remissionsgrad-Ortskurven bei der quantitativen DC. Durch integrierende Analog-Digitalwandlung und digitales Glätten wird das Signal/Rausch-Verhältnis verbessert. Die Peakerkennung erfolgt mit Hilfe der über eine Ausgleichsparabel numerisch differenzierten Meßkurve. Die Basislinienkorrektur bei nicht aufgelösten Peaks beruht auf einem Vergleich der Tangenten zwischen den Peakminima.
    Notes: Abstract The paper describes the principles of a programm for numerical peak detection and numerical integration for area determination by digital computers with respect to thin-layer chromatography. Integrating analog to digital conversion and digital smoothing will improve the signal to noise ratio. The first derivative will be found by smoothed numerical differentiation and is used for peak detection. The actual base line is corrected by eomparision of the tangents between the minima of the peaks.
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    Fresenius' Zeitschrift für analytische Chemie 269 (1974), S. 206-208 
    ISSN: 1618-2650
    Keywords: Best. von Dimethylsulfat in Luft ; Chromatographie, Dünnschicht ; Umsetzung zu Nitroanisol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Methode beschrieben, die es gestattet, Dimethylsulfat (DMS) im Bereich der maximalen Arbeitsplatzkonzentration von 0,05 mg/m3 entsprechend 0,01 ppm zu bestimmen. Zunächst wird DMS zur Anreicherung an Kieselgel adsorbiert. Nach Desorption mit Aceton wird DMS mit 4-Nitrophenol-Na zu 4-Nitroanisol umgesetzt und dünnschicht-chromatographisch durch Intensitätsvergleich mit Standards bestimmt. Zur Erfassung des MAK-Wertes sind mindestens 500 l Probevolumen nötig. Bei einer Sauggeschwindigkeit von 3–4 l/min dauert daher eine Probenahme 2–2,5 Std. Über diesen Zeitraum sollten bei einer Raumluftuntersuchung möglichst ähnliche Konzentrationsverhältnisse vorliegen.
    Notes: Abstract A method is reported which allows the determination of dimethyl sulphate (DMS) in the range of the threshold limit of 0.05 mg/m3 resp. 0.01 ppm. At first DMS is concentrated by adsorption on silica gel. After extraction with acetone and reaction with 4-nitrophenol sodium salt to 4-nitroanisol the DMS is determined by thin-layer chromatography. Evaluation by comparison of intensity with standard spots. For the determination of the threshold limit at least 500 l of sample volume are needed. With an air sampling rate of 3 to 4 l/min the duration of sampling is 2 to 2.5 h. During this time the concentration of the examined air should not vary too much.
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 19-23 
    ISSN: 1618-2650
    Keywords: Best. von Phthalsäure ; Chromatographie, Dünnschicht ; Remissionsmessung, Kopplung mit Tischrechner
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Am Beispiel der Bestimmung von Phthalsäure wird die on line-Kopplung eines programmierbaren elektronischen Tischrechners über einen Integrator zur automatischen quantitativen Auswertung von Dünnschicht-Chromatogrammen durch Messung der Remission beschrieben. Das Verfahren arbeitet mit Mittelwertbildung der Integratorwerte der Scans in und gegen die Fließrichtung, um Basislinienfehler zu eliminieren. Der Rechner ermittelt aus den Vergleichsflecken über die Methode der kleinsten Summe der Fehlerquadrate die Eichgerade und berechnet hierüber die Substanzmenge in den Analysenflecken. Für die Auswertung wird eine quadratische Abhängigkeit der Fläche unter der Remissionsgrad-Ortskurve von der Substanzkonzentration angenommen. Die erreichte Genauigkeit lag bei etwa 2–2,5% (genäherte relative Standardabweichung).
    Notes: Abstract The paper describes the coupling of TLC-photometer, electronic integrator and desk calculator for the determination of phthalic acid by measurement of the remission at 280.3 nm. The average of integrator counts by scanning in and against development of the plate avoids errors caused by base line-drifts. From standards on the plate results a straight line by least squares using the quadratic proportionality of peak area to concentration. From this straight line the concentrations will be determined. The error of this method is in the range of 2–2.5% (relative standard deviation).
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 16-19 
    ISSN: 1618-2650
    Keywords: Best. von Organ. Säuren ; Chromatographie, Dünnschicht ; aliphatisch, aromatisch, Reisstärkeschichten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Aliphatic monocarboxylic, dicarboxylic, hydroxy, keto and amino acids were separated on rice starch thin layers with the solvent system: ethanol/water/ammonia (78∶20∶13). Different aromatic acids were separated on the same support with the solvent system: ethanol/n-butanol/water/ammonia (40∶30∶15∶15). Rf- and RM-values were determined and the validity of Martin's theoretical postulates on the relationship between chemical structure and Rf-values in partition chromatography was displayed. Calculation of group and basic constants was also carried out.
    Notes: Zusammenfassung Aliphatische Monocarbon-, Dicarbon-, Hydroxy-, Keto und Aminosäuren wurden dünnschicht-chromatographisch auf Reisstärke getrennt (Fließmittel: Äthanol/ Wasser/Ammoniak [78∶20∶13]). Verschiedene aromatische Säuren wurden auf der gleichen Schicht mit dem Fließmittel Äthanol/n-Butanol/Wasser/Ammoniak (40∶30∶15∶15) getrennt. Rf- und RM-Werte wurden bestimmt. Aufgrund der theoretischen Aufstellungen von Martin für die Beziehung zwischen Rf-Werten in der Verteilungs- chromatographie und chemischen Strukturen wurden Gruppen- und Grundkonstanten bestimmt.
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 128-128 
    ISSN: 1618-2650
    Keywords: Trenn. von Pseudohalogeniden ; Chromatographie, Dünnschicht ; Fertigfolien, Nachweisgrenzen
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 356-359 
    ISSN: 1618-2650
    Keywords: Nachw. von Pesticiden ; Chromatographie, Dünnschicht ; Nitroverbindungen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird eine Analysenmethode zum Nachweis und zur Trennung von 16 Nitro-Pesticiden beschrieben. Nach einer dünnschicht-chromatographischen Trennung werden die Nitroverbindungen in primäre aromatische Amine übergeführt, die durch Diazotierung und Kupplung mit Bratton-Marshall Reagens nachgewiesen werden. Die photometrische Messung des eluierten Azofarbstoffes gestattet eine quantitative Bestimmung.
    Notes: Abstract An analysis method for the detection and separation of sixteen nitro-pesticides is described. After thin-layer chromatographical separation, the nitro-compounds are converted to primary aromatic amines which are detected by diazotization and subsequent coupling with Bratton-Marshall reagent. The photometric measuring of the azo-dye, obtained by elution, permits quantitative determination.
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 366-367 
    ISSN: 1618-2650
    Keywords: Nachw. von δ-Aminolävulinsäure-Dehydratase-Inhibitoren ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
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    Fresenius' Zeitschrift für analytische Chemie 270 (1974), S. 367-368 
    ISSN: 1618-2650
    Keywords: Nachw. von Peroxidase-Inhibitoren ; Chromatographie, Dünnschicht
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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