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  • Electron microscopy  (160)
  • Immunocytochemistry  (149)
  • Triticum aestivum  (105)
  • Modelling
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  • 101
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 206 (1980), S. 303-318 
    ISSN: 1432-0878
    Schlagwort(e): Area postrema, rat ; Ependyma ; Cyst ; Circumventricular organs ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Peculiar cells forming cysts were observed in the area postrema and sometimes also in the choroid plexus and the tela chorioidea near the area postrema, and were studied in detail by electron microscopy. The cytological features of the cyst cell and its junctional relationship to neighboring cells imply that cyst cells are derived from ependymal and choroid epithelial cells. The cyst cells usually contact directly the perivascular spaces of postremal, choroidal or pial capillaries, where the cytoplasm is often considerably attenuated. The cystic lumen is commonly filled with a flocculent material. The limiting membrane of the cystic lumen, which frequently bears cilia and microvilli, has the same thickness as the surface cell membrane. In many cases, the cyst is surrounded by the cytoplasm of a single cell. In some cases, however, two cells participate in the formation of the cyst, although one is only a slender process and joined by a zonula occludens with the main cyst cell. Horseradish peroxidase (HRP) injected into the cerebrospinal fluid (CSF) space failed to enter the cystic lumen. A possible significance of the cyst in relation to the CSF and blood circulation was considered.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 102
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 206 (1980), S. 355-365 
    ISSN: 1432-0878
    Schlagwort(e): LRH neurons ; Prosimians (Tupaia, Galago) ; Fluorescence ; microscopy ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Reactive LRH neurons were characterized in prosimians (Tupaia and Galago) by immunofluorescence using rabbit immunesera against unconjugated synthetic LRH, or LRH conjugated with bovine serum albumin. These neurons, which vary individually in number in one species, are mainly concentrated in the rostral hypothalamus (medial preoptic area and anterior hypothalamic area) and in the lamina terminalis. In contrast to the simians and man, immunoreactive perikarya were not routinely found in the mediobasal hypothalamus of the prosimians investigated in the present study. Reactive axons of the hypothalamo-hypophyseal tract are more numerous and conspicuous in the retrochiasmatic area and in the postinfundibular eminence. They give rise to radiating collaterals ending mainly around the capillaries of the primary portal plexus of the median eminence and of the infundibular stem (where they are generally more numerous). Reactive axons of the preopticoterminal tract, originating from the perikarya of the lamina terminalis, end around the capillaries of the vascular organ or below and between the ependymal cells lining its ventricular side. In Galago a small but very distinct tract of reactive axons runs under the optic chiasma, between the lamina terminalis and the ventral labium of the infundibulum. Very fine reactive extrahypothalamic axons were observed in the posterior part of the habenular ganglia, along the preamygdaloid portion of the stria terminalis and along the blood vessels of the parolfactory area.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 103
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 210 (1980), S. 447-459 
    ISSN: 1432-0878
    Schlagwort(e): Lipid ; Kidney tubules, proximal ; Autoradiography ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Lipid metabolism in the cells of the renal proximal convoluted tubules (PCT) was investigated in healthy fowls and in fowls with the Fatty Liver and Kidney Syndrome (FLKS). The tissue was fixed at 10–25 min intervals after intravenous injection of 3H-oleic acid. The distribution of autoradiographic grains was analysed by the “circle method”. In normal cells most of the silver grains were associated with the cytoplasmic organelles. Lipid droplets and Golgi elements had the highest specific activity relative to the nuclear activity, which was little above background level. Lysosome-like bodies and mitochondria had lower values. In the cells of the FLKS-affected birds a large proportion of the grains was located over the lipid droplets, which are abundant in this condition. The specific activity of the cytoplasmic organelles was barely 2-fold higher than the nuclear activity. The results suggest that there is a diminished incorporation of esterified fatty acids by the organelles of these cells and that the excess is transferred to the lipid droplets. The identity of low electron density particles observed in the PCT cells of severely affected birds is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 104
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 211 (1980), S. 331-343 
    ISSN: 1432-0878
    Schlagwort(e): Gut hormones ; Endocrine cells ; Electron microscopy ; Immunocytochemistry ; Peptidergic innervation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Histological, cytochemical and immunocytochemical methods were used in light and electron microscopical studies to demonstrate the presence of a neuroendocrine system in the gut of the urodele, Salamandra salamandra. Cytochemical stains capable of detecting peptide-producing endocrine cells demonstrate cells reacting with Masson's silver (argentaffin) method, Grimelius' argyrophil silver method, masked metachromasia method and the lead haematoxylin stain. Using antisera raised to a variety of mammalian gut peptides, cells containing bombesin-, gastrin-, somatostatin-, substance P- and glucagon-like immunoreactivity were identified; vasoactive intestinal polypeptide- and substance P-like immunoreactivities were found in nerve fibres in the submucous and myenteric plexus. No immunoreactivity was detected for motilin, gastric inhibitory polypeptide, cholecystokinin or secretin. The ultrastructure of the immunoreactive cells and nerves was revealed by the semithin/thin method. All the cells identified contained numerous electrondense secretory granules, which varied in their chracteristic morphological structure from one cell type to another. The evidence collected in this study indicates that a complex neuroendocrine system regulating gut function is present in this amphibian and may have developed prior to the emergence of the phylum.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 105
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Biologically active peptides ; Lymnaea stagnalis ; Neurohormone ; Neurotransmitter
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Perikarya and nerve fibers were immunocytochemically identified in the central nervous system of the pond snail Lymnaea stagnalis by means of the unlabelled antibody enzyme method with antisera to 15 biologically active peptides of vertebrates: vasopressin, vasotocin, oxytocin, α-melanocyte stimulating hormone (α-MSH), met-enkephalin, somatostatin, glucagon, insulin, glucose-dependent insulinotropic peptide (GIP), vaso-active intestinal polypeptide (VIP), gastrin, secretin, pancreatic polypeptide (PP), Substance P, calcitonin. No immunostaining was obtained with antisera to β-endorphin, cholecystokinin (CCK), neurophysin I and II. Particular neurons could be identified with two antisera (anti-vasopressin/vasotocin, anti-α-MSH/metenkephalin, anti-substance P/PP, anti-PP/gastrin). Apparently this indicates that populations of cells identified with a given antiserum may consist of more than one cell type. Only a few of the new peptidergic cells appeared to be identical with classical neurosecretory cells. Thus the growth hormone producing Light Green Cells stained with anti-somatostatin and the axon terminals of the ovulation hormone producing Caudo-Dorsal Cells with anti-met-enkephalin. Whether this indicates structural identity of the growth hormone with somatostatin and of the ovulation hormone with met-enkephalin remains to be investigated. Just like the classical neurosecretory cells a number of the new peptidergic cells (anti-glucagon, -insulin, -met-enkephalin, -somatostatin, and -PP positive cells) send their axons to the peripheries of commissures, connectives or nerves. Thus these cells can be considered as probably neuroendocrine. The classical neurosecretory cells release their products into the haemolymph from these sites. Other new peptidergic cells (e.g., anti-vasopressin, -vasotocin, -oxytocin and -GIP positive cells) have axons that terminate, probably synaptically, on other neurons, indicating that they are “more conventional” neurons, their products being neurotransmitters/neuromodulators. It can also not be excluded that some cells of a population containing a given peptide are neuroendocrine and others make contact with other neurons.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 106
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 232 (1983), S. 593-600 
    ISSN: 1432-0878
    Schlagwort(e): Peritrophic membrane ; Insect ; Microvilli ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A double plasma membrane (DPM) surrounding intestinal microvilli of the migratory milkweed bug, Oncopeltus fasciatus, is described. Mutant and wild types of the phytophagous insect have been studied by conventional SEM and TEM procedures with the use of membrane-enhancing staining methods. Longitudinal and transverse sections revealed a DPM surrounding microvilli and continuing over the apical portions of the intestinal cell. The outer membrane of the DPM contributes to an intestinal lining or peritrophic membrane (PTM), which apparently accumulates in layers. SEM studies reveal a rugose intestinal surface and complete PTM in both starved and fed insects. Only rarely are exposed microvilli seen by SEM. SEM examinations also enable the observation of numerous blebs on the luminal side of the PTM apparently held in position by a neck-like attachment and apparently derived from the outer membrane of the DPM. Preliminary TEM studies of microvilli revealed unique microvesicle-like structures, lying just inside the inner membrane of the DPM, which may be of membrane origin based on their typical trilaminar appearance after en bloc staining with uranyl acetate. Highly ordered microfilaments were observed to occupy the most central aspect of the microvilli.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 107
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 69-80 
    ISSN: 1432-0878
    Schlagwort(e): Somatostatin ; Hypothalamus ; Immunocytochemistry ; Human ; Rhesus monkey
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunocytochemical methods were used to compare the localization of somatostatin (SRIF) in the human and rhesus monkey hypothalamus. The distribution of SRIF-containing cell bodies and fibers is similar in the two species. Perikarya are located predominantly in the periventricular region and to a lesser extent in the ventromedial nucleus. Fibers occur in dense clusters within the periventricular region, ventromedial nucleus, arcuate nucleus, median eminence, and pericommissural area of both species. Analysis of serial sections suggests that fibers originate from cells in the periventricular region, extend ventrally through the ventromedial and arcuate nuclei to terminate around the portal vessels of the infundibular stalk, and thereby participate in the regulation of anterior pituitary function. Somatostatinergic fibers are also found surrounding non-immunoreactive perikarya in the ventromedial nucleus and periventricular region of both primates. This arrangement may support somatostatin's postulated role as a neurotransmitter or neuromodulator. The strong similarity between the localization of hypothalamic SRIF in the human and rhesus monkey supports the use of the rhesus monkey as a model for the study of somatostatin as a neuroendocrine regulator in the human.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 108
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 23-33 
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Vasopressin ; Dorsomedial hypothalamus ; Amygdala ; Locus coeruleus
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Recently, the existence of a vasopressin-immunoreactive cell group was described in the bed nucleus of the stria terminalis (van Leeuwen and Caffé 1983). In the present investigation additional nuclei containing vasopressin-immunoreactive cells were found, after colchicine pretreatment, in the dorsomedial hypothalamus, medial amygdaloid nucleus and the locus coeruleus. Vasopressin-immunoreactive cells in the dorsomedial hypothalamus and medial amygdaloid nucleus are small (8–14 μm and 10–14 μm, respectively), while those in the locus coeruleus are medium-sized (20–25 μm). Incubation with anti-bovine neurophysin II and anti-rat neurophysin revealed staining of the same cell group in the above-mentioned areas. None of these cell groups show stained cells after incubation with anti-oxytocin and anti-bovine neurophysin I. When sections of the homozygous Brattleboro rat, which shows a deficiency in vasopressin synthesis, are incubated with anti-vasopressin, anti-bovine neurophysin II, or anti-rat neurophysin, no immunoreactivity can be observed in these brain regions. The above-mentioned cell groups may contribute to the vasopressinergic innervation of brain sites that have been reported to persist after lesioning of the suprachiasmatic, paraventricular and bed nuclei of the stria terminalis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 109
    ISSN: 1432-0878
    Schlagwort(e): α-Endorphin ; Immunocytochemistry ; Median neurosecretory cells ; Peptidergic neurones ; Calliphora vomitoria
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A group of the 24–26 paraldehyde fuchsin-positive median neurosecretory cells (MNC) in the pars intercerebralis of the brain of the blowfly, Calliphora vomitoria, has shown immunoreactivity towards three different antibodies to α-endorphin, a peptide that corresponds to the amino acid sequence present between residues 61 and 76 of the precursor molecule, β-lipotropin (β-LPH). The immunoreactive material could be followed in axons within the median bundle, the tract through which neurosecretory material from the MNC is passed down to the corpus cardiacum (CC). The α-endorphin-immunoreactive material was observed leaving the CC in the cardiac-recurrent nerve, dorsal to the proventriculus, in the direction of the abdomen. The cells that contain the α-endorphin-like material are different from those of the MNC that contain insulin-, pancreatic polypeptide-, and gastrin/CCK-like peptides. This finding demonstrates the considerable complexity and peptidergic nature of the MNC and constitutes further evidence that morphinomimetic-like peptides are present in the nervous system of invertebrates.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 110
    ISSN: 1432-0878
    Schlagwort(e): Angiotensinogen ; Liver ; Kidney ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The renin substrate, angiotensinogen, was localized by immunocytochemistry in liver and kidney of normal rats by the use of an antiserum directed against pure rat angiotensinogen. This substrate was also examined in rats after bilateral nephrectomy, which is known to increase plasma angiotensinogen, and in rats treated with colchicine, which inhibits serum protein secretion. In normal rat liver, light microscopy showed the presence of immunoreactive material in a very few cells. The number of stained hepatocytes rose in rats treated with colchicine or after bilateral nephrectomy. Immuno-staining increased further when rats were both nephrectomized and colchicine treated. In the kidney, angiotensinogen was specifically located as granular formations in nephrocytes of the proximal tubule but never in the granular cells of the juxtaglomerular apparatus. The localization of these granular formations under the brush border suggests that angiotensinogen is reabsorbed from the glomerular ultrafiltrate rather than synthesized in the kidney.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 111
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 471-474 
    ISSN: 1432-0878
    Schlagwort(e): Prolactinergic neurons ; Immunocytochemistry ; Cerebral ganglion ; Styela plicata
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Peptidergic neurons have been detected in the cerebral ganglion of the ascidian Styela plicata by means of cytochemical methods. After incubation with a mammalian antibody to human prolactin the perikarya show a strong immunoreactivity. The possible function of prolactin-like peptides in the nervous system of protochordates is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 112
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 234 (1983), S. 125-134 
    ISSN: 1432-0878
    Schlagwort(e): Vasopressin ; Immunocytochemistry ; Electron microscopy ; Hypothalamus ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Vasopressin-containing neurons, identified by immunocytochemistry, are located predominantly in the posterior magnocellular division of the paraventricular nucleus of the rat hypothalamus. By electron microscopy, the immunoreaction product is seen within the cell bodies and neuronal processes. In the perikarya and dendritic processes, the immunoreactive material is associated primarily with neurosecretory granules. Axonal processes, identified by their content of microtubules and accumulation of neurosecretory granules, show the immunoreaction product in association with both of these organelles. Afferent axo-dendritic, axo-somatic and putative axo-axonic synapses with immunostained vasopressinergic neurons can be identified. The presynaptic profiles do not contain immunoreactive material. This study contributes to the ultrastructural characterization of vasopressinergic neurons in the paraventricular nucleus and of their afferent synaptic input.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 113
    ISSN: 1432-0878
    Schlagwort(e): Fibronectin ; Lung ; Development ; Ultrastructure ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In a previous study changes in the macrodistribution of fibronectin during rat-lung development were examined. Using the peroxidase-antiperoxidase immunocytochemical technique, we have demonstrated the presence of fibronectin in embryonic, neonatal, and adult rat lung at the ultrastructural level. In the embryo, fibronectin is found both in an intra-and extracellular association with isolated pneumoblasts, and in a periodic distribution along the basal lamina. The neonate displays fibronectin in an intracellular association with early type-I cells and on their basal and luminal surfaces, but not in association with type-II cells. Neonatal basal lamina is diffusely labeled by anti-fibronectin antiserum. Fibronectin in adult tissue is found both intracellularly and on the basal and luminal surfaces of type-I cells but not in type-II cells. The basal lamina and interstitial connective tissue are slightly or non-reactive. These observations confirm and extend our initial suggestion that fibronectin is involved in rat-lung development.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 114
    ISSN: 1432-0878
    Schlagwort(e): Dictyosome-like structures ; Golgi apparatus ; Phosphatidylcholine ; Laminated figures ; Electron microscopy ; Guinea pig
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Dictyosome-like structures (DLS) of guinea pig spermatocytes, when prefixed in mixtures of glutaraldehyde and tannic acid, exhibited laminated figures with a repeating periodicity of about 4.5 nm in the spaces between DLS saccules or in association with the surfaces of the DLS saccules. These laminated figures were similar to those figures derived from saturated lipids in other tissues. Alternatively, spaces between saccules were collapsed leaving only thin, electron-dense material separating adjacent saccules. These changes were not observed when the DLS were prefixed in glutaraldehyde before exposure to tannic acid. The presence of laminated figures following fixation with tannic acid and osmium tetroxide suggests that saturated lipids are present in, or associated with, the intersaccular regions of the DLS. The distribution of laminated figures in other membrane structures was not affected by post fixation with tannic acid nor were laminated figures comparable to those of the DLS observed between cisternae of the Golgi apparatus. These results support previous conclusions that DLS are distinct from Golgi apparatus and are a unique component of the germ cell cytoplasm.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 115
    ISSN: 1432-0878
    Schlagwort(e): Urotensin ; Caudal neurosecretory system ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The localization of urotensin I has been investigated in the caudal neurosecretory system of the white sucker (Catostomus commersoni). The peptide is present in all the cells of the system both large and small, in the large axons passing to the urophysis, and in fine beaded fibres not only within the urophysis but also in a fine plexus lateral to the large cells in the spinal cord proper. The possibility that the caudal neurosecretory system is not a functionally uniform system but rather a collection of dissimilar cells of different synaptic inputs with a common entity, urotensin I, is discussed. Moreover, the feasibility of a urotensin I feedback loop is described.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 116
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 51-58 
    ISSN: 1432-0878
    Schlagwort(e): Parathyroid glands ; Electron microscopy ; Light microscopy ; Quantitative histology ; Mongolian gerbil
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Stereology and semi-automatic image analysis were used with the aim of comparing the structure of parathyroid glands from untreated adult Mongolian gerbils fixed by immersion with those fixed by perfusion. Subclassification of the chief cells based upon the staining affinity or electron density of the cytoplasm was readily performed only in glands fixed by immersion, and so-called atrophic cells were observed only in these glands. The atrophic cells were often surrounded by “light” chief cells. In glands fixed by perfusion, “light” chief cells were only rarely encountered. A significant difference between glands fixed by immersion and those fixed by perfusion was found only with regard to the form of cells and nuclei, those fixed by perfusion being more spherical. When comparing individual cells within glands fixed by immersion, “light” chief cells were more spherical and had a significantly larger nuclear and cellular size, and a lower mitochondrial volume density than the “intermediate”/“dark” chief cells. Otherwise there were no significant differences in any of the parameters investigated. These data indicate that occurrence of socalled “light” chief cells and atrophic cells is a result of improper fixation. The results of this study do not favour the concept of a functional cycle with a simultaneous occurrence of active and inactive cells within parathyroid glands.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 117
    ISSN: 1432-0878
    Schlagwort(e): Pituitary rat ; LH cells ; FSH cells ; ACTH cells ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary By means of immunocytochemistry, the development of ACTH-, LH- and FSH cells was examined in the anterior pituitary of 5-day-old neonatal, 15-day-old immature and adult rats. ACTH-positive cells are angular and the periphery of these cells is strongly reactive with anti-ACTH serum. In contrast, LH- and FSH-immunopositive cells are ovoid elements, ranging in cell size and intensity of staining. Angular cells, in which only the cell periphery reacted with anti-LHβ serum, were observed in neonatal and immature rats; however, these cells were not stained with either anti-FSHβ serum or anti-ACTH serum. Observation of serial semithin sections revealed that ACTH-immunopositive cells do not react with either anti-LHβ or anti-FSHβ serum. Finally, it was observed that ACTH cells and LH cells are both functionally differentiated already in 5-day-old neonatal rats.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 118
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 77-83 
    ISSN: 1432-0878
    Schlagwort(e): Pituitary (rat) ; LH cells ; FSH cells ; Rapid freeze-substitution ; Immunocytochemistry ; Ferritin antibody
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Rapid freeze-substitution fixation was employed in immunocytochemical studies on the localization of LH and FSH in the typical gonadotrophs of the anterior pituitary in the untreated male rat; a modification of a recently described ferritin antibody method (Inoue et al. 1982) was used in these studies. It was shown that rapid freeze-substitution fixation provides good preservation not only of the ultrastructure but also of the antigenicity. Both LH and FSH were clearly demonstrated in the same gonadotrophic cells, but the subcellular localization of these gonadotrophins differed: (i) LH was mainly located in small secretory granules, 250–300 nm in diameter; (ii) FSH was mainly present in large secretory granules, up to 500 nm in diameter. In the pituitary gland of the adult male rat, all gonadotrophs that react to antibodies against gonadotrophins are characterized by small and large secretory granules. Other types of cells of the anterior pituitary containing either small secretory granules or resembling corticotrophs with secretory granules assembled at cell periphery did not react to either anti-LH beta or anti-FSH beta serum. For light microscopy, the peroxidase antibody method was used. All of the gonadotrophin-positive cells contain both LH and FSH. None of the pituitary cells reacted to antibody against only one gonadotrophin. However, some cells are “LH-rich” while other cells are “FSH-rich”.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 119
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 153-158 
    ISSN: 1432-0878
    Schlagwort(e): Bovine ; Interdigitating cell ; Lymphoid tissues ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Electron-microscopic studies of lymphoid tissues from bovine fetuses and from calves disclosed a non-lymphoid cell type in the thymus-dependent zones of secondary lymphoid tissues and in the thymus that is distinguishable from reticulum cells, epithelial and endothelial cells, and macrophages. Based on morphological and topographical criteria, the cell is identified as the interdigitating cell. In addition, studies of the tissues of normal and virus-challenged fetuses, and of conventionally reared calves, indicated that the interdigitating cells originate from monocytoid cells, which undergo differentiation in the thymus-dependent zones during an immune response.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 120
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 159-169 
    ISSN: 1432-0878
    Schlagwort(e): Anterior pituitary ; Gonadotropic cells ; Immunocytochemistry ; Testosterone binding ; Cryo-ultramicrotomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Several attempts have been made to localize steroids by means of immunocytological techniques. However, these methods were found inadequate for detecting steroids bound to their receptors. To localize endogenous testosterone (T) in its target cells at the ultrastructural level, an immunocytological technique was performed on ultrathin sections obtained by cryo-ultramicrotomy. T was detected in the pituitary glands obtained from intact male or female rats and castrated rats, but not in castrated + adrenalectomized rats. Animals were also injected either with testosterone, with other steroids (estradiol, progesterone, corticosterone) or with an androgen antagonist (cyproterone acetate). In addition, some ultrathin sections were preincubated either with phosphate buffers of various pH, corticosterone, cyproterone acetate solution, or with T solution. The content of T in the pituitary before and after fixation was measured by radioimmunoassay; it decreased after fixation. T immunoreactivity was localized in the gonadotropic cells only, both in the male and female rats. At the subcellular level, the immunoreactivity was detected in the cytoplasmic matrix and in the nucleus. Immunoreactive T disappeared 1) in rats after castration+adrenalectomy; by means of radioimmunoassay no T was measured in these pituitary glands; 2) in rats injected with 25 (μg/rat of cyproterone acetate; 3) after preincubation of pituitary sections on a drop of cyproterone acetate (1 × 10-6 M). The immunocytological reaction was not modified when the rats were injected with estradiol, progesterone or corticosterone (1 mg/rat), or after preincubation of the sections with corticosterone (1 × 10-3 M), or a buffer solution at pH 7.6. Lower or higher pH values led to a strong decrease in the immunoreactivity. After injection of T (15 μg/rat) the immunocytological reaction was more abundant in the nucleus and less in the cytoplasm. The immunoreactivity was again observed when the sections were preincubated with cyproterone acetate solution and then with T solution. These data suggest that T can be detected by means of immunocytochemistry. It is probably bound to a specific binding site.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 121
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Supraoptic nucleus (SON) ; Oxytocin neurones ; Neuronal appositions
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Pre-embedding immunocytochemistry was performed on vibratome sections of the hypothalamus of lactating rats using antiserum directed against oxytocin. Electron microscopy revealed that numerous immunopositive somata and dendrites in the supraoptic nucleus were in direct apposition, without glial interposition; a number of them were also bridged by “double” synapses. The observations support the contention that the ultrastructural reorganisation of the nucleus apparent at lactation affects the magnocellular neurones secreting oxytocin.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 122
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 243-249 
    ISSN: 1432-0878
    Schlagwort(e): Gap junction ; Electron microscopy ; Freeze fracture ; Cell-to-cell communication
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Gap junctions exist in the septa between the segments of the lateral giant axons in the ventral nerve cord of the crayfish Procambarus. A large increase in the resistance (uncoupling) of these gap junctions was brought about by mechanical injury to the axonal segments. Both thin sections and freeze-fracture preparations were used to monitor the morphological changes which occurred up to 45 min after injury. There was no apparent change in the organization (a loose polygonal array) of the intramembrane particles which make up the junctional complex up to 45 min after injury. In some instances, however, the intramembrane particles appeared to have moved away from the junctional area. Other junctional regions were internalized and appeared similar to what have been called annular gap junctions. Also at this time (20–25 min after injury), a dense cytoplasmic plug formed in uninjured axon near the junctional region. It is concluded that the gap junctions that exhibit a loose polygonal organization of the intramembrane particles may be either in a state of low resistance (coupled) or a state of high resistance (uncoupled).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 123
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 427-432 
    ISSN: 1432-0878
    Schlagwort(e): DPP IV ; Salivary glands ; Ultrastructural localization ; Immunocytochemistry ; PAP
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructural localization of dipeptidyl peptidase IV (DPP IV) (EC 3.4.14.5) in rat submandibular and parotid glands was studied immunocytochemically by the peroxidase-antiperoxidase (PAP) method, using a monospecific antiserum against rat kidney DPP IV. There were no differences in the immunocytochemical localization of DPP IV between submandibular and parotid glands. In these glands, DPP IV was primarily found to be associated with the luminal and intercellular canalicular plasma membranes of acinar cells and with the luminal plasma membranes of intercalated and striated duct cells. Occasionally, immunoreaction of DPP IV was detected in cytoplasmic vesicles (vacuoles), lysosomes, and multivesicular bodies in some acinar cells as well as in ductal epithelial cells. Furthermore, the reaction product was also found within the lumina of peri-acinar and peri-ductal capillaries and in the cytoplasm of some fibroblasts in the interstitial connective tissue. These data suggest that DPP IV in the submandibular and parotid glands may play some role in the secretion or reabsorption processes of secretory proteins and peptides in these glands.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 124
    ISSN: 1432-0878
    Schlagwort(e): S-100 protein ; Thymus ; Interdigitating cells ; Immunocytochemistry ; Man
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The present study deals with the localization and ultrastructure of S-100-immunoreactive cells in the human thymus. These immunoreactive cells are distributed mainly in the medulla with some scattered elements in the cortex. Electron-microscopic observation revealed that the cells are characterized by an irregularly shaped nucleus, tubulovesicular structures in the cytoplasm and characteristic interdigitations of the plasma membrane. The cells often embrace lymphocytes with their branched processes. On the basis of these morphological features, the immunostained elements were identified as interdigitating cells (IDCs). The immunocytochemistry for S-100 visualizes the precise distribution and extension of the IDCs under the light microscope and indicates that the IDCs form no structural networks such as those established by the thymic epithelial cells. Since the IDCs in human lymph nodes have also been reported to contain S-100-like immunoreactivity, S-100 protein can be regarded as a useful marker for identifying the IDCs in the human thymus and other lymphoid organs.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 125
    ISSN: 1432-0878
    Schlagwort(e): Ovulation ; Perfusion ; Graafian follicle (rabbit) ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Ovulation was induced in rabbits by intravenous administration of human chorionic gonadotrophin (HCG), and 4–5 h later the ovaries were isolated and introduced into an in-vitro perfusion system containing synthetic medium with albumin. Rupture of follicles occurred in vitro within the physiological time range (mean 11.3 h after injection of HCG), although with a reduced frequency. Preovulatory and ruptured follicles were studied in detail by light and electron microscopy. In the granulosa layer of ruptured or preovulatory follicles cytoplasmic blebbing activity, disappearance of CallExner bodies and differentiation toward luteinized cells were found. Perhaps the most important sign of normal preovulatory development in vitro was that the basement membrane surrounding the granulosa layer was penetrated by projections of granulosa cells. In the absence of this penetration phenomenon the granulosa layer prolapsed out of the follicle. Immediately before rupture, follicles showed marked degeneration, restricted to the outer layers of the apical wall, which is compatible with the hypothesis that degradative enzymes are released close to the surface of preovulatory follicles. Although the majority of follicles that ovulated under in-vitro conditions showed the same kind of morphological alterations as can be seen in vivo, occasional atypical ruptures occurred without any overt signs during perfusion. Also technical manipulations of the perfusion system, e.g., nonphysiological increase of perfusion pressure, could force follicles to rupture. This illustrates the importance of careful morphological study of all ovaries perfused in vitro before conclusions are drawn.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 126
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; FMRF-amide ; Neurotransmitter ; Palaemon
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary By use of a specific antiserum against the molluscan cardio-excitatory tetrapeptide FMRF-amide in combination with the PAP-method it was possible to obtain positive immunocytochemical reactions in several neurosecretory regions of the eyestalk of the prawn Palaemon serratus. FMRF-amide-like material was found in perikarya and nerve fibers of the medulla terminalis and in neurons in the lamina ganglionaris. The immunoreactivity observed in the glandular tissue located at the basal insertion of the eyestalk muscles must be ascribed to a non-specific reaction. The identification of immunopositive nerve fibers, ending on a nerve bundle in the medulla terminalis, and the fact that immunoreactive material was absent in the neurohemal sinus gland seem to indicate a neurotransmitter/neuromodulator function.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 127
    ISSN: 1432-0878
    Schlagwort(e): Fetal porcine pituitary ; ACTH, MSH, β-LPH, α- and β-endorphin, GH, PRL ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The aim of the present study on the fetal porcine pituitary was (1) to detect by means of the immunoperoxidase technique the earliest stages of cells producing polypeptide hormones: β-MSH, ACTH, β-LPH, α- and β-endorphin, growth hormone (GH) and prolactin (PRL), (2) to study the development of the synthesis and the storage of these hormones during fetal life, and (3) to detect whether several hormones can be located in one and the same cell. The corticotropic cells were revealed as the earliest functional elements of the fetal anterior pituitary. Our results indicate clearly that ACTH, β-MSH, β-LPH, α- and β-endorphin appear at 34 days in the same regular, round or ovoid cells; no differences in the time of their appearance could be observed. The ACTH-cells, irregular or angular in shape and endowed with cytoplasmic processes such as described in the adult pituitary, were not seen until day 50. The first GH-cells were detected between 40 to 45 days of fetal life. From day 45 to 90, the GH-cells greatly increased in number and in staining intensity of their progressively extending cytoplasmic area, but they displayed the same regular and round shape. The PRL-cells were the last cell type to appear in the fetal pituitary. The first PRL-cells, small in size and round or ovoid in shape with a high nucleus/cytoplasm ratio, were detected at day 70. At day 80, the PRL-cells increased in size and staining intensity. They displayed an irregular elongated or stellated shape and cytoplasmic processes resembling those characteristic of the adult pituitary. These data suggest that in the fetal porcine pituitary: (1) ACTH, β-LPH and related peptides are synthesized and stored in the same cells, and (2) PRL and GH appear in individual cellular elements.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 128
    ISSN: 1432-0878
    Schlagwort(e): Anterior pituitary, porcine ; Gonadotropic hormones (FSH, LH) ; Immunocytochemistry ; Cellular compartments
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Pre- and post-embedding immunocytochemical methods based on the use of specific antibodies against β-subunits of porcine LH and FSH were applied to determine the changes occurring in the anterior pituitary of the pig after gonadectomy. The results showed that (1) the total number of immunoreactive gonadotropes increased from 21–25% in control animals to 24–37% in castrated animals; (2) all gonadotropes contained both LH and FSH; (3) several types of immunoreactive LH/FSH cells were revealed; and (4) the two immunocytochemical methods used with dispersed cells localized the hormones in the same subcellular sites. However, the staining intensity in the different locations varied depending on the method applied. With the post-embedding method, a dense reaction product was found in the secretory granules but the cisternae of RER and the Golgi saccules were always slightly reactive. After the pre-embedding method, the staining intensity in the RER-cisternae and in the Golgi saccules was greatly increased. Thus, the two methodological approaches used in this study have permitted to visualize immunocytochemically the gonadotropic hormones not only at the sites of their storage but also along the intracellular pathway of the secretory material, i.e., at the site of its synthesis and during its passage via the Golgi zone.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 129
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 171-180 
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Ultrastructure ; Supraoptic nucleus ; Neuropil ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The neuropil located ventral to the SON was investigated by the use of immunoperoxidase staining for neurophysins, oxytocin and vasopressin, and electron miroscopy. The study was performed in six groups of rats: 1) control; 2) infusion of isotonic saline into the CSF; 3) infusion of hypertonic saline into the CSF; 4) drinking hypertonic saline for 4 days; 5) same as group 4 but injection of colchicine into the CSF on second day of dehydration; 6) salt loading for 3 months. In the control rats the ventral neuropil contained a few immunoreactive processes, the general morphology of which was completely different from that of the neurosecretory axons emerging from the SON at its dorsal aspect. In rats of groups 3 to 6 the ventral processes (VP) became loaded with neurosecretory granules, whereas the perikarya and axons were depleted. Based on their general morphology and reactivity pattern it is suggested that the VP are dendrites. Most of these “dendrites” were embedded in a glial cushion formed by the processes of a particular type of marginal glia. Some of these “dendrites” enveloped an arteriole penetrating the optic tract. All VP were rich in synaptic contacts. The possibility that the VP of neurosecretory cells may be functionally related to the subarachnoid CSF and the arteriolar blood flow is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 130
    ISSN: 1432-0878
    Schlagwort(e): ACTH cells ; Immunocytochemistry ; Morphometry ; Spontaneous hypertension
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary ACTH-immunoreactive cells in the anterior pituitary of 4-week-old spontaneously hypertensive rats (SHR) were studied with immunocytochemical and morphometric techniques. The results were compared with data from age-matched normotensive Wistar-Kyoto rats (WKY). No significant differences were found in volume density and average size of ACTH-immunoreactive cells between these two strains. However, SHR showed a significantly larger anterior lobe (2 P 〈 0.01) than WKY, indicating that the total number of ACTH-immunoreactive cells in the anterior pituitary is greater in SHR than in WKY. These data are in agreement with radioimmunological determinations showing a significantly elevated content (2 P 〈 0.01) but only a moderately higher concentration (0.05 〈 2 P 〈 0.10) of ACTH in the anterior pituitary of SHR as compared to WKY. The present results suggest an enhanced availability of ACTH in the anterior pituitary of 4-week-old SHR, a fact which could explain the markedly enhanced stress-induced release of ACTH previously found in these animals. This study further supports the hypothesis that, among other factors, an instability of the hypothalamo-pituitary-adrenal axis may contribute to the development of genetically programmed hypertension.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 131
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 517-525 
    ISSN: 1432-0878
    Schlagwort(e): Bone marrow ; Actin ; Cell motility ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Blood cells proliferate extravascularly in the bone marrow and enter the circulation by migrating through endothelial cells of venous blood sinuses. This migration, or diapedesis, was suspected to involve actin. To test for the presence and distribution of actin, sections of rat bone marrow were examined by indirect immunocytochemistry. Affinity purified rabbit antichicken gizzard actin antibody, and goat-antirabbit IgG-FITC, or goat antirabbit IgG colloidal gold probes were used. The migrating cell contacts the endothelial cell and forms a podosome (a cortical bleb). Immunocytochemistry shows this region to contain actin. As diapedesis proceeds the podosome deforms, then breaches the endothelial cell. At this time the anterior portion of the leukocyte shows heavy labeling for actin. When the migratory cell traverses approximately half of its length through the endothelial cell, actin appears prominent in the caudal region of the cell. The immunocytochemical data suggest that actin is nonrandomly distributed in leukocytes undergoing diapedesis and may be a component of the force-generating mechanism responsible for this transcellular migratory event.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 132
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 149-154 
    ISSN: 1432-0878
    Schlagwort(e): Pituitary gland, pars distalis ; Innervation ; Synaptoid contacts ; Electron microscopy ; Rana temporaria L
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In the pars distalis of the hypophysis of adult Rana temporaria, three types of nerve-fiber profiles were found at two distinct sites, in both lateral parts of the bordering regions of the anterior lobe with the intermediate lobe of the hypophysis. The first type of nerve-fiber profile consists of bundles of very fine axonal elements (diameter: 〈0.7 μm). The second type is formed by larger nerve fibers (diameter up to 4 μm) containing a few neurosecretory granules of approximately 100 nm. The third type of nervefiber profile resembles the second type but these nerve fibers make synaptoid contacts on at least two different types of glandular cells. The possible functional significance of these nerve fibers in the pars distalis is discussed. No nerve fibers were found (1) in the central part of the bordering region of the pars distalis with the intermediate lobe, (2) at the bordering region with the median eminence and (3) with the neurohypophysial stalk, and (4) in all other parts of the pars distalis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 133
    ISSN: 1432-0878
    Schlagwort(e): Pituitary gland ; Goat ; Folliculo-stellate cell ; GH cell ; S-100 protein ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Goat pituitary glands were immunohistochemically studied with antisera for bovine S-100 protein, rat LHβ, FSH, TSHβ, prolactin, ovine GH, and porcine ACTH1–39 by use of the superimposition technique on adjacent sections. Folliculo-stellate (F-S) cells were divided into two categories on the basis of ultrastructural properties: One consisted of a mass of agranular cells in which the pseudolumina were equipped with microvilli and cilia. Elongate gap junctions were often observed among these cells. The other was a group of granulated cells with or without pseudolumina. In this group the gap junctions were shown to be disintegrated. The dense granules 150–250 nm in diameter began to accumulate in the cells. However, neither type of these F-S cells was immunostained for S-100 protein. On the other hand, numerous polygonal, elongate, irregular or stellate cells containing S-100 protein were distributed throughout the gland. Most of them were immunohistochemically identical with the GH cells laden with the secretory granules 250–450 nm in diameter, but some of them were identical to TSH and prolactin cells which immunostained faintly for S-100 protein. This appears to be the first demonstration of GH cells intensely immunostained for S-100 protein.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 134
    ISSN: 1432-0878
    Schlagwort(e): Hagfish ; Brain ; Pituitary ; FMRF-amide ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Paraffin sections of brain and pituitary of the hagfish Eptatretus burgeri were immunostained with an antiserum to FMRF-amide. Immunoreactivity was visible in a large number of neurons in the posterior part of the ventromedial hypothalamus and in long neuronal processes extending cranially from the hypothalamus to the olfactory system and caudally to the medulla oblongata. FMRF-amide-like immunoreactivity was also found in cells of the adenohypophysis. These observations suggest that the hagfish possesses a brain FMRF-amide-like transmitter system and pituitary cells containing FMRF-amide-like material. Antisera to ACTH, α-MSH and pancreatic polypeptide gave no immunoreaction in hagfish brain or pituitary.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 135
    ISSN: 1432-0878
    Schlagwort(e): Crustacean hyperglycemic hormone ; Astacus leptodactylus ; Immunocytochemistry ; Quantitative electron microscopy ; Secretory cycle
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunocytochemical staining demonstrates striking differences in staining intensity among individual crustacean hyperglycemic hormone (CHH)-producing cells in the eyestalk of the crayfish Astacus leptodactylus. Based on these differences we arbitrarily subdivided the CHH-cells into three categories representing increasing immunoreactivity respectively: + cells, + + cells, and + + + cells. Electron microscopic investigations reveal that these differences in immunostaining are correlated with differences in the numerical density of the neurosecretory granules in the cytoplasm and that these may reflect differences in activity among the CHH-cells. Morphometric analyses at the light- and electron-microscopic levels indicate that the three distinguished categories of immunopositive cells represent different stages in the CHH-synthesizing process of the cells. The results of the present study demonstrate the application of the PAP-technique at the light-microscopic level as a method to obtain information pertaining to the dynamics of secretory activity of the CHH-cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 136
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 321-327 
    ISSN: 1432-0878
    Schlagwort(e): Neuropeptide Y ; Immunocytochemistry ; Respiratory tract ; Ear, middle
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Nerve fibres displaying neuropeptide-Y (NPY) immunoreactivity are abundantly distributed in the respiratory tract of cats, guinea-pigs, rats and mice. Fine beaded NPY fibres were seen in whole-mount spreads of the middle-ear mucosa. In the nasal mucosa and in the wall of the Eustachian tube NPY fibres were numerous around arteries and arterioles but sparse in the vicinity of veins; single fibres were found close to the acini of seromucous glands. In the tracheobronchial wall NPY fibres occurred in the proximity of blood vessels, in the subepithelial layer and in the smooth muscle. Surgical and chemical (6-hydroxydopamine treatment) sympathectomy resulted in disappearance of adrenergic and NPY-containing nerve fibres in the nasal mucosa. Sequential staining with antibodies against dopamine-β-hydroxylase (DBH) and NPY revealed that DBH and NPY occur in the same perivascular nerve fibres in the nasal mucosa. The distribution of NPY fibres in the respiratory tract suggests multiple functions of NPY, such as regulation of local blood flow, glandular secretion and smooth muscle activity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 137
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 238 (1984), S. 165-175 
    ISSN: 1432-0878
    Schlagwort(e): Mesonephros ; Pig embryo ; Glomerulus ; Microvasculature ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Vascularization of the pig mesonephros was investigated in embryos 5–8 cm in length. Vascular injections with microfil were cleared and dissected; corrosion casts were studied under the scanning electron microscope (SEM). Perfusion-fixed tissue was used for SEM and transmission electron microscope (TEM) studies, including freeze-fracture specimens. The branches of one mesonephric artery carry up to 15 glomeruli. Several glomeruli occupy the same arterial branch, with very short afferent arterioles proper. The efferent vessels, frequently 2–5, leave the extensive vascular pole opposite the entering arteriole and split into peritubular capillaries radiating towards the superficial veins. These capillaries form vascular regions in the shape of flattened pyramids. Along its course, one nephron is supplied by vessels derived from 4–7 glomeruli. The nephrons have less vascular contact than in the definitive kidney. The ultrastructure of the single mesonephric vessels matches the metanephric counterparts. Epithelioid cells with renin granules are common in afferent arterioles, larger arteries, and efferent vessels. The lobulated glomeruli are up to 750 μm long and flattened, showing the usual features of podocytes, mesangial cells, and an attenuated endothelium with fenestrations between 50 and 250 μm. It partially retains its own basement membrane. There is no proximal mesangium.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 138
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 238 (1984), S. 387-394 
    ISSN: 1432-0878
    Schlagwort(e): Pacinian corpuscles, cat ; Denervation ; Atrophy ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructure of Pacinian corpuscles of the cat located in the crural region and innervated by the interosseous nerve was studied 1 to 14 months after denervation. Both the Pacinian inner core and capsule remained well preserved one month after denervation. However, the denervated inner cores underwent progressive atrophy and wasting, which resulted in a gradual reduction of the amount of inner-core cells and lamellae, widening of interlamellar clefts, formation of empty spaces in the axial region and a considerable increase in the number of collagen fibrils. In spite of the wasting, the inner core still survived 14 months after denervation, but at least half of its volume became occupied by collagen fibrils which surrounded the remaining inner-core cells and lamellae. Collagen fibrils assembled in the denervated core were markedly thinner than those found in the capsule, as is also the case in normal Pacinian corpuscles. In the capsule, discrete focal degeneration, occasional pyknosis of the innermost capsular cells and macrophage infiltration were observed from the first month after nerve section onward, but the number of capsular layers remained within the normal range (30–40) up to 14 months after denervation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 139
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Biogenic amines ; Vasotocin ; Lymnaea stagnalis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Consecutive sections of certain neurons in the central ganglia of the pond snail Lymnaea stagnalis appear to be immunoreactive to anti-dopamine and anti-serotonin. The Cerebral Giant Neurons stain in addition with antivasotocin. The observations indicate the presence of two biogenic amines within the same neuron and in addition their co-existence with a biologically active peptide.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 140
    ISSN: 1432-0878
    Schlagwort(e): Retinal photoreceptors ; Opsin ; Optic nerve ; Immunocytochemistry ; Cyclostome, Myxine glutinosa
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Opsin-immunoreactive sites in the eye and optic nerve of the hagfish, Myxine glutinosa, were studied by use of light-microscopic pre- and postembedding peroxidase-antiperoxidase or avidin-biotin-peroxidase techniques, and the immuno-electron-microscopic protein A-gold method. At the light-microscopic level, a strong opsin immuno-reaction was obtained on the outer segments of the photoreceptor cells with sheep and rat antibodies against bovine (rhod)opsin. These outer segments were located in the marginal photoreceptor space and in follicles of the retina, as well as in the tubular lumen of the optic nerve. Ultrastructurally, two classes of outer segments can be distinguished; most of them exhibited a strong antiopsin reaction, while certain elements lacked immunoreactivity with the antisera employed. The protein A-gold particles marked opsin-immunoreactive sites on the photoreceptor membranes. The presence of opsin-immunoreactive material in the retina and optic nerve of the hagfish strengthens the view that this primitive eye lacking a cornea, lens and vitreous body is engaged in light perception. The morphological similarity between the eye and pineal tissue is discussed in connection with the absence of a pineal organ in this species.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 141
    ISSN: 1432-0878
    Schlagwort(e): Pancreatic islets ; Adrenergic innervation ; Insulin secretion ; Chemical sympathectomy ; Adrenalectomy ; Fluorescence histochemistry ; Immunohistochemistry ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Morphological changes in the adrenergic innervation of pancreatic islets after chemical sympathectomy by use of 6-hydroxydopamine and the influence of the sympatho-adrenal system on insulin secretion were investigated in the mouse and rat. Fluorescence histochemistry revealed a clear-cut reduction in the number of adrenergic nerve fibers in the pancreatic islets 2 days after administration of 6-hydroxydopamine; the reduction was more pronounced in the rat than in the mouse. In the rat, a partial regeneration was seen after 6 weeks. In the pancreas of the mouse, after administration of 6-hydroxydopamine, a severe damage of unmyelinated nerve fibers was revealed electron microscopically. However, no ultrastructural or immunohistochemical alterations could be demonstrated in the endocrine cells of the islets. 6-Hydroxydopamine induced a depression of basal plasma insulin concentrations in mice and an elevation in rats. Adrenalectomy depressed basal plasma insulin levels in mice. The α-adrenoceptor antagonist phentolamine enhanced insulin secretion in normal mice. The secretory response of insulin to phentolamine was diminished by chemical sympathectomy and almost abolished by adrenalectomy or the combination of chemical sympathectomy and adrenalectomy. Thus, the effect of phentolamine is probably mediated by liberated catecholamines. It is concluded that basal insulin secretion is partially regulated by the sympatho-adrenal system and that species differences exist in this respect. In addition, the results suggest that endogenous catecholamines have the ability to promote insulin secretion.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 142
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Vasoactive intestinal polypeptide ; Radioimmunoassay ; Gut hormones ; Anura
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunocytochemical and radioimmunological techniques with region specific antisera have been used to identify a vasoactive intestinal polypeptide-like material in the anuran intestine. Seven species of Anura were investigated: Bombina bombina, Alytes obstetricans, Rana temporaria, Rana esculenta, Hyla arborea, Hyla crepitans and Bufo bufo. In five of the species (A. obstetricans, R. temporaria, H. arborea, H. crepitans and B. bufo) vasoactive intestinal polypeptide-like immunoreactive mucosal endocrine cells and nerve fibres in all layers of the gut wall, were detected by both immunofluorescence and peroxidase-antiperoxidase methods. In the other two species, R. esculenta and B. bombina, no mucosal endocrine cells were detected although the vasoactive intestinal polypeptide-immunoreactive nerve fibres were plentiful. Radioimmunoassay showed the presence of significant amounts of vasoactive intestinal polypeptide-immunoreactivity in intestinal extracts from all species. The highest quantities were present in those anurans with both immunostained cells and nerves. Gel permeation chromatography showed that most of the vasoactive intestinal polypeptide-like peptide eluted in a position identical to that of natural mammalian (porcine) vasoactive intestinal polypeptide. The results indicate that a vasoactive intestinal polypeptide-like peptide is well represented in the Anura and that it is immunologically very similar to the mammalian peptide.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 143
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 216 (1981), S. 471-479 
    ISSN: 1432-0878
    Schlagwort(e): Ovulation ; Perfusion ; Graafian follicle (Rabbit) ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In the present investigation the ultrastructure of isolated rabbit ovaries, perfused with different media for various time periods, was studied. The steroid hormone production by the perfused ovary was also determined. Perfusion with Medium 199 results in prominent interstitial ovarian oedema which increases with perfusion time. Even after the addition of 6–10 % Dextran T40, oedema appears in the interstitial tissue of the ovary. Perfusion solutions with osmotically active colloid particles of large molecular size (Dextran T70; average molecular weight 70,000 and bovine serum albumin), cause less distortion in the ovarian structure, and ultrastructurally the ovarian tissues appear essentially the same as in the control ovaries. The results indicate that the perfused rabbit ovary, under strictly controlled conditions, can be used as an experimental model for studies of various aspects of ovarian function, including follicular rupture.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 144
    ISSN: 1432-0878
    Schlagwort(e): Hypothalamus (rat) ; Differentiation ; Transplant ; Histofluorescence ; Immunocytochemistry ; Autoradiography
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Hypothalamic tissue from 16 to 18-day fetal rats was transplanted onto the choroidal pia overlying the superior colliculus in adult female rats. After survival periods of 2 weeks to 19 months, brains containing transplants were processed for monoamine fluorescence histochemistry, immunohistochemistry for three neuropeptides (LHRH, somatostatin, neurophysin), or for autoradiography in ovariectomized hosts that received [3H] estradiol. Most of the transplants survived and retained or increased in size; 14 of 25 transplants examined by fluorescence histochemistry were found to contain median eminence-like structures. In almost all of the transplants that were stained for neuropeptides, beaded processes and occasional cell bodies were observed. Although immunoreactive fibers were found near blood vessels, no palisade arrangement typical of the normal median eminence was evident. Each of the hypothalamic transplants on which steroid autoradiography was performed contained clusters of estrophilic neurons, the intensity of labeling of which was comparable to that seen in the host hypothalamus. These results indicate that many characteristic morphological and chemical features of the hypothalamus, which are not evident in the 16 to 18-day fetus, are elaborated in transplants during the survival period in the host. Transplantation of fetal hypothalamus to adult choroidal pia thus appears to be a valuable approach for studying the factors, humoral or neural, that regulate the differentiation of this brain region.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 145
    ISSN: 1432-0878
    Schlagwort(e): Lipolytic peptide B ; Pituitary ; ACTH/MSH cells ; Brain ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Several lipid-mobilizing peptides occur in the pituitary, among them β-lipotropin and “lipolytic peptide A and peptide B”. The latter two peptides are distinct from β-lipotropin and appear to be chemically related to the neurophysins. Immunohistochemistry has now revealed that the lipolytic peptide B of the pituitary is localized in the ACTH- and MSH-cells. In addition, immunoreactive peptide B was found in axons of the posterior lobe of the pituitary. Immunoreactive peptide B was found also in nerve fibers and nerve cell bodies in the hypothalamus, particularly in the hypothalamo-hypophyseal tract and in the magnocellular neuronal system. Immunoreactive nerve fibers were numerous also in the periventricular nucleus of the thalamus. The antiserum against peptide B cross-reacts with neurophysin I, and hence, it cannot be excluded that at least part of the immunostaining in the brain reflects the presence of the latter component. However, the regional distribution of immunoreactive peptide B and neurophysin was not identical. Therefore, it is possible that authentic peptide B occurs not only in the pituitary but also in the brain.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 146
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 210 (1980), S. 269-282 
    ISSN: 1432-0878
    Schlagwort(e): Monoaminergic neurons ; Retina ; Amacrine cells ; Neurotoxins ; Mudpuppy, Necturus maculosus ; Neurotransmitters ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The mudpuppy retina was investigated with the histofluorescence method of Falck and Hillarp in normal animals and in animals injected intraocularly with α-methylnoradrenaline, 5,6-dihydroxytryptamine, or a combination of the two drugs. Catecholaminergic amacrine cells were found to form a thin layer of terminals at the border between the inner nuclear and the inner plexiform layers. Catecholaminergic interplexiform cells were not found. Indoleamine-accumulating amacrine cells were also observed. They are fifteen to twenty times more numerous than the catecholaminergic cells, and their terminals occur diffusely throughout the inner plexiform layer. In a number of eyes the majority of the indoleamine-accumulating terminals were eliminated with intraocular injections of the neurotoxin, 5,7-dihydroxytryptamine, but the reproducibility of this effect was not consistent. Intravitreal injections of 5,6-dihydroxytryptamine were used to label both types of neurons for electron microscopy. They were found to make conventional type synapses on amacrine cells and, less frequently, on bipolar cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 147
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 210 (1980), S. 353-357 
    ISSN: 1432-0878
    Schlagwort(e): Merkel cells (reptiles) ; Epidermis ; Lizard ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Examination of the labial epidermis of the lizard Lacerta sicula revealed cells displaying all features of Merkel cells. These cells are located in the stratum basale of epidermal pegs and are arranged in clusters.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 148
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 211 (1980), S. 293-301 
    ISSN: 1432-0878
    Schlagwort(e): Paneth cell ; Hibernation ; Intestine ; Hypothermia ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructure of Paneth cells from jejuno-ileal segments of the small intestine of the ground squirrel, S. lateralis, was examined under normal euthermic conditions and during the profoundly depressed metabolic conditions of natural hibernation. Paneth cells obtained from hibernating animals gave evidence of markedly reduced activity when compared to Paneth cells from euthermic animals. In hibernating animals, the nuclei were smaller, with less prominent nucleoli and with an increased proportion of heterochromatin. In hibernating animals, the rough endoplasmic reticulum was fragmentary and poorly organized, in contrast to the typical arrangement of concentric lamellae seen in euthermic animals. Although the total number of ribosomes was decreased in hibernating animals, there were proportionally more free ribosomes than in euthermic animals. Paneth cells from hibernating animals also contained a greater number of apical secretory granules which were smaller and more variable in electron density than granules from control animals. These ultrastructural features indicate that during hibernation the Paneth cell is relatively quiescent.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 149
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 216 (1981), S. 205-214 
    ISSN: 1432-0878
    Schlagwort(e): Compound eyes ; Insects ; Crustaceans ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The basement membrane of the compound eye of four insect species and three crustacean species was investigated employing electron microscopy. The basement membrane consists of an extracellular (basal lamina) and a cellular portion, the latter being composed of the flattened terminal extensions of cone cells and accessory pigment cells in insects and distal pigment cells in crustaceans. Other cells can also contribute to the basement membrane. It is thus a complex structure in all well-developed compound eyes. The cellular contributions vary in different species and were found to correlate to specific taxonomic units.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 150
    ISSN: 1432-0878
    Schlagwort(e): Gastrin ; CCK ; Median eminence ; Electron microscopy ; Xenopus laevis (Amphibia, Anura)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary By use of an anti-gastrin serum and colloidal gold- or ferritin-labelled sheep anti-rabbit γ-globulins, nerve fibres and nerve terminals containing a gastrin-like substance were characterized at the ultrastructural level in the median eminence of Xenopus laevis. These immunoreactive fibres contain neurosecretory granules displaying medium to high electron density and a mean diameter of 75 nm. Labelling intensity varies from granule to granule. This is the first demonstration at the ultrastructural level of the precise location of a gastrin-like hormone in the median eminence of a vertebrate.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 151
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 217 (1981), S. 211-223 
    ISSN: 1432-0878
    Schlagwort(e): Pituitary gland ; Pars intermedia ; Electron microscopy ; Sheep
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Light microscopy of coronal sections of the sheep pars intermedia revealed a compact, incompletely lobulated V-shaped region about 15–20 cells thick, situated between the pars distalis and the pars nervosa. A prominent hypophysial cleft and follicles containing a colloid-like substance were seen. Using electron microscopy, five cell types could be distinguished: pars intermedia glandular cells, pars distalis-like glandular cells, interstitial cells, follicular cells and cleft lining cells. The polyhedral to pear-shaped pars intermedia glandular cells predominated. They contained dense-cored, membrane-bound granules near the Golgi complex, and larger, irregular vesicles with finely granular contents of varying electron density throughout the remaining cytoplasm; exocytotic release of granules was occasionally observed. Smaller numbers of cells resembling those seen in the pars distalis were scattered throughout the pars intermedia. Interstitial cells usually possessed elongated cytoplasmic processes which extended between the glandular cells, and were characterized by deeply indented nuclei, elaborate junctional complexes and an absence of cytoplasmic granules. Cells lining the follicles resembled the interstitial cells. The major cells bordering the hypophysial cleft were triangular in section and bore irregular microvilli on their free surface. The pars intermedia appeared to be less vascular than the remainder of the hypophysis and only occasional fenestrated capillaries were seen. Nerve profiles were rare.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 152
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 238 (1984), S. 113-119 
    ISSN: 1432-0878
    Schlagwort(e): Crustacea ; Gastrointestinal hormones ; Neuropeptides ; Immunocytochemistry ; Cuticle ; Cancer magister
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A gastric peptide from the Dungeness crab (Cancer magister), extracted and characterized previously (Larson and Vigna 1983b), was localized in the foregut (stomach) of this species by immunocytochemistry using antisera specific for the bioactive carboxy-terminal amino acid sequence common to gastrins and cholecystokinins (CCKs). Immunoreactivity was found in all gastric epithelial cells and in the procuticle. Electron microscopy revealed an absence of peptidergic secretory granules in the gastric epithelial cells. The pattern of immunostaining suggests that the gastric epithelial cells secrete this peptide apically where it is incorporated into the cuticle lining the lumen. Specific immunostaining could not be demonstrated in various neural ganglia or in the hypodermis. The distribution of this peptide is different from that of gastrin/CCK in vertebrates and other invertebrates. This suggests that the crab gastric peptide is sufficiently similar to gastrin/CCK to react with C-terminal specific antisera, but may be anatomically, functionally, and possibly phylogenetically otherwise unrelated.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 153
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 238 (1984), S. 289-296 
    ISSN: 1432-0878
    Schlagwort(e): Somatostatin (SRIF) ; Brain ; Pituitary gland ; Immunocytochemistry ; Teleosts
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunocytochemical investigations show that somatostatin (SRIF)-like immunoreactive material is present in the brain and the pituitary of nine different species of teleosts. In the brain, immunoreactive perikarya and fibers are observed in the preoptic periventricular nucleus, the entopeduncular nucleus, the anterior periventricular nucleus, and the nucleus lateralis tuberis. In the pituitary, SRIF-like-immunoreactive fibers occur in the proximal pars distalis (PPD), which contains the growth hormone (GH)-secreting cells. Nerve fibers are scattered among GH cells (cyprinids), or end on the basal lamina at the neuroglandular interface of the PPD (eel, salmonids). In the eel, the proximal neurohypophysis does not penetrate deeply into the PPD that is very poorly vascularized. In some species, e.g. Myoxocephalus, SRIF-like immunoreactive fibers are also observed in the caudal neurohypophysis, and even among MSH cells of the pars intermedia. In long-term starved carps and eels, the amount of SRIF-like material in the pituitary is clearly reduced. A possible role of SRIF in the concomitant stimulation of GH cells is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 154
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Slug brain ; Somatostatin-like material ; Maturation hormone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunocytological tests reveal the presence of a somatostatin-like substance in perikarya and axons in the brain of the giant slug Limax maximus L. Controls carried out on adjacent sections with absorbed antiserum or different antibodies raised against several biologically active peptides of vertebrates (ACTH-17-39, α- and β endorphin, α- and β MSH, methionin-enkephalin, TRH) demonstrate the specificity of the “staining”. However, some cells are both somatostatin- and FMRF-amide-positive. In the cerebral ganglia, the right Z-area cells, responsible for the synthesis of the maturation hormone (MH) are strongly somatostatin-positive. These results suggest a similarity between the MH and the somatostatin-like material contained in the Z-area cells. The simultaneous presence of two peptides in one and the same cell, the nature (elementary granules or soluble product) of the material, and its site of release are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 155
    ISSN: 1432-0878
    Schlagwort(e): FMRF-amide ; Immunocytochemistry ; Nervous system ; Microstomum lineare (Turbellaria)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The central nervous system (CNS) and the peripheral nervous system (PNS) of the flatworm Microstomum lineare were studied by means of the peroxidase-antiperoxidase (PAP) immunocytochemical method, with the use of antisera to the molluscan cardioactive peptide FMRF-amide. FMRF-amide immunoreactive perikarya and nerve fibres are observed in the CNS and the PNS. In the CNS, immunoreactive perikarya and nerve fibres occur in the brain, in the epithelial lining and the mesenchymal surroundings of the ciliated pits, and positive fibres in the longitudinal nerve cords. In the PNS, immunoreactive fibre bundles with variocosities occur in the pharyngeal nerve ring, in symmetrical groups of perikarya on each side of the pharynx, and in the mouth area. Positive perikarya and meandering nerve fibres appear in the intestinal wall. A few immunoreactive cells and short nerve processes are observed at the male copulatory organ and on both sides of the vagina. Some immunoreactive peptidergic cells do not correspond to cells previously identified by histological techniques for neurosecretory cells. The distribution of immunoreactivity suggests that the FMRF-amide-like substance in CNS and PNS in this worm has roles similar to those of the brain-gut peptides in vertebrates. The status of FMRF-amide-like peptides as representatives of an evolutionarily old family of peptides is confirmed by the positive immunoreaction to anti-FMRF-amide in this primitive microturbellarian.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 156
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 207 (1980), S. 511-517 
    ISSN: 1432-0878
    Schlagwort(e): Female hamster ; Harderian gland ; Testosterone ; Tubular clusters ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Distinct differences occur in the pigmentation and ultrastructural features of the Harderian glands in male and female hamsters. The results of a study on the effect of testosterone on the fine structure of the female Harderian glands are presented here. Glands from three groups of hamsters were examined at intervals up to 49 days: (1) testosterone injected, receiving 2mg testosterone propionate in 0.1 ml sesame oil per day; (2) sham-injected, receiving 0.1 ml sesame oil per day; (3) untreated controls. Testosterone injections caused a reduction in the number of dark-brown pigment granules in the acinar cells starting on the 6th day, whereas clusters of tubules, typical of adult male glands, appeared on the 4th day and increased in number thereafter. Lamellar structures, normally present in the female gland, decreased in testosterone treated specimens. These changes reversed after cessation of testosterone treatment. It is concluded that exogenous testosterone administered to female hamsters modifies the pigmentation and ultrastructure of their Harderian glands towards the male type and that this is a reversable phenomenon. There also appears to be an inverse relationship between the presence of tubular clusters in the acinar cells, and the degree of pigmentation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 157
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 208 (1980), S. 171-181 
    ISSN: 1432-0878
    Schlagwort(e): Microtubules ; Dendritic spine apparatus ; Synapse ; Development ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Using techniques for enhanced microtubular preservation, including albumin pretreatment (Gray, 1975), occipital cortex of rats was studied electron microscopically at various ages of development. A close structural relationship was seen between microtubules, sacs of SER and the postsynaptic “thickening” in primordial spines and with the dense “plate” material of spine apparatuses. Stereoscopic preparations in addition show a more complicated substructure than previously described for the “plate”. Microtubules may contribute to the formation of the “plate” of the spine apparatus which in turn is associated with the postsynaptic “thickening” of the mature spine. Possible functional correlates are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 158
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 209 (1980), S. 131-135 
    ISSN: 1432-0878
    Schlagwort(e): Skeletal muscle ; Bupivacaine ; Degeneration ; Satellite cells ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Rat lumbrical muscles were incubated in a concentration of 10-2 M bupivacaine for 5 or 15 min and examined after further incubation in the absence of the drug for periods totalling 1, 2, and 3h. Electron microscopy showed that muscle fibers and their component organelles and myonuclei underwent a series of irreversible degenerative changes. However, satellite cells retained their normal morphology under similar conditions. It is concluded that satellite cells are responsible for the rapid regeneration of muscles that follows degeneration induced by bupivacaine. The role of satellite cells in muscle regeneration is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 159
    ISSN: 1432-0878
    Schlagwort(e): Anterior pituitary ; Corticotrophs ; Immunocytochemistry ; Growth hormone ; Prolactin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Two antisera, Y-10 and Y-18 were raised in rabbits against synthetic human β-endorphin conjugated to bovine serum albumin and keyhole limpet haemocyanin respectively. Antiserum Y-10 has been shown by radioimmunoassay to be highly specific for human β-endorphin with minimal or no cross-reactivity against other pituitary peptides whilst antiserum Y-18 crossreacted on an equimolar basis against β-endorphin and β-lipotropin. When used in the immunohistochemical procedure, both antisera specifically stained the corticotrophs in human anterior pituitary tissue. A similar effect was observed when antiserum Y-18 was applied to rat anterior pituitary tissue in the immunohistochemical procedure. Y-10 antiserum, on the other hand, stained not only rat corticotrophs but also somatotrophs. The somatotrophin staining could not be attributed to the enkephalins reported to be present in these cells. The non-specific β-endorphin antiserum Y-18 was used to stain anterior pituitaries from dehydrated and adrenalectomized rats as well as rats of the Brattleboro strain. In tissues from the three experimental animals, cells that stained positively for β-endorphin did not give a positive immunoreaction for ACTH and vice versa in some other sections. It is concluded that under the physiological conditions, formalin fixation of the tissue causes the proopiocortin molecule to be “trapped” in a conformation such that either ACTH or β-endorphin-like determinants are available for reacting with the appropriate antiserum.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 160
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 215 (1981), S. 643-649 
    ISSN: 1432-0878
    Schlagwort(e): T-lymphocytes ; Blast cells ; Autoradiography ; Electron microscopy ; Stereology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary As a companion to an earlier study, the morphometric attributes of stimulated (blast-derived) lymphocytes in mouse axillary lymph nodes have been established using stereological and autoradiographic methods. Blast transformation was induced in vivo with dinitrochlorobenzene (DNCB) and stimulated cells were labelled with tritiated thymidine. Random samples of cells were taken for light and electron microscopic morphometry. In comparison to the unstimulated lymphocyte, the stimulated cell increased in size and possessed a greater plasma membrane surface area. Increase in cell size was the result of increases in the volumes of all measured subcellular compartments both in the nucleus and the cytoplasm. Heterogeneity of the stimulated cell population precludes firm conclusions regarding the significance of all these ultrastructural changes, though alterations in cell surface are discussed in the context of known biochemical differences accompanying blastogenesis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 161
    ISSN: 1432-0878
    Schlagwort(e): Neuropeptides ; Substance P ; Chicken gut ; Radioimmunoassay ; Immunocytochemistry ; Smooth muscle motility
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The distribution and cellular localization of substance P in the chicken gut was studied by immunocytochemistry and immunochemistry. Substance P-containing nerve fibers are numerous in the gut wall. They occur in the smooth muscle layer as well as in the mucosa, where they are associated with blood vessels or surround the intestinal crypts. The fibers are particularly numerous in the myenteric and submucosal plexuses, where substance P-containing nerve-cell perikarya are also encountered. Substance P was found also in scattered endocrine cells of the small intestine, caeca and colon. Previously, bombesin-containing cells, which are numerous in the proventriculus, have been mistakenly identified as substance P cells due to crossreactivity of certain antisera against substance P. Immunochemistry revealed the highest concentration of substance P in the duodenum. The gel chromatographic behavior of chicken substance P differs slightly from that of synthetic bovine substance P, suggesting that chicken substance P differs structurally from mammalian substance P. Substance P-containing nerve fibers in the chicken gut develop slowly after hatching, apparently beginning in the duodenum; at approximately 20 weeks after hatching the distribution pattern is fully developed. A functional investigation was performed on the isolated chicken caecum to clarify the role of substance P in the contractile behavior of smooth muscle. Substance P contracted the caecum over a wide dose range; the contractile response was greater in 20 week-old chickens than in 4 and 10 week-old animals. Electrical field stimulation caused a relaxation of the caecum and a contraction upon cessation of stimulation. Neither of these responses, both of which are neurally mediated, were inhibited by adrenergic and cholinergic blockade. It is conceivable that the contractile response following electrical stimulation is caused by substance P released from nerve fibers in the smooth muscle.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 162
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 207 (1980), S. 135-142 
    ISSN: 1432-0878
    Schlagwort(e): Caudal neurosecretory system ; Poeciliidae ; Electron microscopy ; Salinity changes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The urophysis or neurohemal contact site of the caudal neurosecretory system of Mollienesia sphenops, the black molly, was studied in animals adapted to an artificial seawater environment. This species of fish was chosen for these studies because of its known ability to osmoregulate and its adaptability to the laboratory aquarium. The urophysis of freshwater acclimated mollys contained an abundance of neurosecretory granules. However, in fish subjected to a seawater environment for one week the number of neurosecretory granules was significantly decreased. In addition, there was an increase in blood cell infiltration of the urophysis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 163
    ISSN: 1432-0878
    Schlagwort(e): Pancreatic polypeptide (PP)-like material ; Immunocytochemistry ; Neuropeptides ; Neurosecretory cells ; Calliphora erythrocephala
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The brain of the blowfly, Calliphora erythrocephala, has been studied by means of the peroxidase-antiperoxidase immunocytochemical method, with the use of antibodies to bovine pancreatic polypeptide (BPP). A number of immunoreactive neurones have been localised, some corresponding to neurones previously identified tentatively as neurosecretory. This finding is further evidence that biologically active peptides, previously considered to be “vertebrate”, also exist in invertebrates. It also supports the concept of their evolutionary origin in nervous tissue.
    Materialart: Digitale Medien
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  • 164
    ISSN: 1432-0878
    Schlagwort(e): Juxtaglomerular apparatus ; Sympathetic innervation ; Renin-angiotensin system ; Electron microscopy ; Fluorescence microscopy ; Tupaia belangeri ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary It has previously been reported that the primitive primate Tupaia belangeri develops a renal failure when exposed to psychosocial stress. In order to learn if this high susceptibility to stress of the Tupaia kidney can be correlated with morphological and functional parameters of the Juxtaglomerular apparatus (JGA) and the renin-angiotensin system, comparative experiments were performed on Tupaia and rat. Our results reveal an outstandingly high potency of the JGA and the renin-angiotensin system in Tupaia as evident from the following findings: The Tupaia JGA contains a great number of epithelioid cells abounding in renin granules (electron microscopy). The renin content of the Tupaia kidney is considerably higher than in the rat (radio-immunoassay). The sympathetic innervation of the kidney and especially of the JGA is abundant in Tupaia (fluorescence and electron microscopy). Catecholamine contents of the kidney and other organs are significantly higher in Tupaia than in rats (spectrophotofluorometry). Our results support the previously developed concept of a potent intrarenal neuroendocrine interaction at the JGA level favouring, under certain conditions of social stress, the development of acute renal failure in Tupaia belangeri.
    Materialart: Digitale Medien
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  • 165
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 212 (1980), S. 465-474 
    ISSN: 1432-0878
    Schlagwort(e): Postcapillary venules ; Calf ; Lymph nodes ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The structure of the postcapillary “high endothelial venules” (HEV) of lymph nodes in calves was studied light and electron microscopically. These venules were detected light microscopically in the paracortical zone by their high cuboidal endothelium, a distinct basal lamina, the migration of lymphocytes through the vessel wall, and the dominance of lymphoid cells in the lumen, often completely obliterating the latter. Ultrastructurally, the endothelial cells (HEC) of the HEV were characterized by a prominent Golgi complex including many small vesicles, a few lysosome-like bodies, and a specific association between mitochondria and rough endoplasmic reticulum (MER). The HEC are connected by desmosomes, whereas the intimate contact points between migrating lymphocytes and endothelial cells could not be classified according to the well-defined junctional types. Lymphocyte migration occurred predominantly intercellularly, i.e., between endothelial cells. Although the overall appearance of the described vessel type in bovines bears resemblance to HEV in other investigated species, several differences occur that most probably are related to species variation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 166
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 213 (1980), S. 37-51 
    ISSN: 1432-0878
    Schlagwort(e): Mesotocin neurons ; Vasotocin neurons ; Avian hypothalamus ; Preoptic area ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The neurosecretory systems producing mesotocin (MT) and vasotocin (VT) (the avian homologues of oxytocin and vasopressin, respectively) were characterized in the brains of the domestic mallard and Japanese quail by means of indirect immunofluorescence techniques using specific antisera. In the anterior preoptic region, including the organum vasculosum of the lamina terminalis, and at different levels of the supraoptic and paraventricular nuclei, separate mesotocin- and vasotocin-producing neurons were identified. Mesotocinergic and vasotocinergic neurons were also located in the tuberomammillary area, among the ectomammillary tract fibers. The supraoptico-neurohypophysial tract, formed by vasotocin- and mesotocincontaining axons, enters the internal zone of the median eminence and ends in the posterior lobe of the pituitary. The external zone of the rostral median eminence appears to contain vasotocin and mesotocin fibers, which terminate in close contact with the capillaries of the hypophysial portal system.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 167
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 216 (1981), S. 557-568 
    ISSN: 1432-0878
    Schlagwort(e): Electron microscopy ; Neuroglia ; Silver impregnation ; Brain ; Cat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The silver-impregnation procedure of Tsujiyama is suitable for demonstration of all three classical types of neuroglial cells; in the present study it was used for electron microscopic identification of neuroglial cells in the brain of the cat. The aim of the present study was 1) to determine impregnated structural correlates of neuroglial cells at the light- and electron-microscopic levels, and 2) to determine whether the method of Tsujiyama is applicable for the electron microscopic identification of the single types of neuroglial cells. Silver deposits were observed over the cytoplasm and processes of astrocytes where numerous glial filaments were present. Oligodendrocytes and microglial cells may be precisely differentiated by use of Tsujiyama's silver impregnation method at the electron microscopic level due to the pattern of silver-deposition in these two basic types of cells. This silver-impregnation method combined with electron microscopy is thus suitable for a precise identification of neuroglial cells; the technique may prove to be very helpful in identification of such categories of neuroglial cells that encompass also the images of cells which cannot be classified by use of the standard methods.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 168
    ISSN: 1432-0878
    Schlagwort(e): Pituitary ; Immunocytochemistry ; Prolactin ; Somatotropin ; Lepidosiren
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The cellular binding sites of anti-oPRL IgG and anti-bSTH IgG were demonstrated in the pituitary glands of Lepidosiren paradoxa, Rana temporaria and Ambystoma mexicanum by means of the unlabeled antibody enzyme method by light and electron microscopy (the latter only in Lepidosiren). With the light microscope PRL or PRL-like substances and STH or STH-like substances were revealed in two different cell types in the distal lobe corresponding to the acidophils. However, as a result of the insufficient differentiation of the acidophils in Lepidosiren after staining with Brookes' procedure it was not possible to distinguish the two types of acidophils in this animal. Treatment with low dilutions of both anti-oPRL and anti-bSTH IgG revealed simultaneous immunocytochemical staining in both types of acidophils in Lepidosiren and in Rana. These results, indicating that there is antigenic cross-reaction between anti-oPRL and anti-bSTH IgG and both PRL and STH in these animals, are discussed. The electron microscopic investigations of Lepidosiren revealed that the specific anti-oPRL IgG reactive cells contain granules ranging in size from 200 to 300 nm, while the specific anti-bSTH IgG reactive cells contain smaller immunoreactive granules ranging from 80 to 160nm.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 169
    Digitale Medien
    Digitale Medien
    Springer
    Plant systematics and evolution 145 (1984), S. 1-13 
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Triticum aestivum ; Aegilops longissima ; Cytogenetics ; homoeologous relationships ; chromosome substitutions ; translocations
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The relationships of three wheat-Aegilops longissima chromosome addition lines A, C, and D with homoeologous wheat chromosomes were studied in PMC meiosis. Substitutions of alien chromosome A for wheat chromosome 6 B, chromosome C for 1 B and chromosome D for 4 B were obtained. The production of 4 BS/C and 7 BS/D chromosome translocations indicated cytogenetic relationships of C partially to homoeologous wheat chromosomes of group 1 and 4, and D partially to homoeologous wheat chromosomes of group 4 and 7.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 170
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 115 (1983), S. 43-51 
    ISSN: 1615-6102
    Schlagwort(e): Digestion ; Membrane flow ; Electron microscopy ; Sarcodina ; Actinophrys sol
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The digestion of food in the heliozoonActinophrys sol is characterized by several distinct membrane events. Initially, extrusomes expand and fuse with each other and with the plasma membrane providing the membrane for the nascent food vacuole. During this process a—presumably lytic—material is secreted. After complete forming of the food vacuole a second type of vesicles fuses with it, whereupon usually lysis of the prey occurs. After denaturation and coagulation of the food, fluid is removed from the food vacuole. This process is accompanied by a high cytotic activity around the periphery of the food vacuole. Following this step, the perinuclear Golgi region shows an active appearance and numerous lysosomes fuse with the food vacuole. In consequence of this the food is degradated. The food vacuole shrinks continuously. Simultaneously vesicles filled with the digested material pinch off from the food vacuole, the content of which shows a more and more condensed mass of undigestible material. The undigestible residues are defecated eventually. The process of digestion is accompanied by an increase in volume and number of electron lucent cytoplasmic vacuoles. These vacuoles gradually become filled with a filamentous material starting with the vacuoles in the cell periphery. As the digestion continues, the vacuolar contents become condensed successively. Synchroneously the vacuoles move towards the cell center. After completion of the digestion, the cytoplasmic vacuoles decrease in volume and number and do not show any longer electron dense contents.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 171
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 115 (1983), S. 104-113 
    ISSN: 1615-6102
    Schlagwort(e): Cereals ; Embryo culture ; Triticum aestivum ; Wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Cell proliferation from the mature embryo of wheat occurs on a defined medium in the presence of 2,4-D. Unorganized growth is observed when the 2,4-D concentration is equal to or greater than 2 mg/l, but increasing levels of 2,4-D inhibit cell division. Cell divisions begin after 4 days in culture from parenchyma cells within and near the procambial tissues of the embryo axis. By day 8 continuous meristematic zones are formed in association with vascular tissues, and DNA synthesis and cell divisions are distributed throughout these zones. No morphological evidence exists to show that these zones consist of proliferating root primordia, which are formed only after the level of 2,4-D falls below some critical concentration. When the concentration of 2,4-D is lowered, the meristematic zones first become dissected and then give rise to many root meristems.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 172
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 115 (1983), S. 202-207 
    ISSN: 1615-6102
    Schlagwort(e): Anacystis nidulans ; Cyanobacterium ; Electron microscopy ; Freeze-fracmres ; Thylakoid degradation ; Ultrathin-sections
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Photooxidative bleaching of the CyanobacteriumAnacystis nidulans was studied by electron microscopic investigation of both freezefractured and thin-sectioned samples. During bleaching four consecutive phases in degradation of photosynthetic membranes (thylakoids) could be characterized: 1. No ultrastructural changes until photosystem II activity is lost. 2. Derangement of characteristic arrangement of thylakoids. 3. Thylakoids visible only in thin-sectioned but not in freeze-fractured samples. 4. Completely bleached cells, only traces in place of former thylakoids visible in thinsectioned samples. Bleaching did not cause lysis of the cells showing that the cytoplasmic membrane was not damaged. Polyhedral bodies also were still detectable in bleached cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 173
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 116 (1983), S. 198-200 
    ISSN: 1615-6102
    Schlagwort(e): Chromosome isolation ; Electron microscopy ; Vicia faba ; Vicia narbonensis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Using a formalin fixation technique whole chromosomes from root tips ofVicia species were isolated into a buffer solution. Combining this technique with the use of a set of reciprocal translocations available for this species—Vicia faba— allowed each member of the karyotype to be isolated and identified. Such isolated chromosomes can be used for optical microscopy or for either transmission or scanning electron microscopy where critical point drying clearly reveals chromatin fibre.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 174
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 116 (1983), S. 209-212 
    ISSN: 1615-6102
    Schlagwort(e): Parapharyngeal mass ; Electron microscopy ; Cytochemistry ; Electron microprobe X-ray analysis ; Ciliate ; Homalozoon vermiculare
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The structure and elemental composition of the granules which make up the parapharyngeal mass of the ciliateHomalozoon vermiculare are analyzed. The mass is made up of two kinds of granules. One is not membrane-bounded and is composed of paraglycogen. The second type is comprised of concentric lamellae. It is rich in magnesium, phosphorus, potassium, and calcium. These results do not support the contention that the granules are directly involved in the process of food vacuole formation. The role of the parapharyngeal mass remains obscure.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 175
    ISSN: 1615-6102
    Schlagwort(e): Cell walls ; Electron microscopy ; Moisture ; Plastic embedding ; Seeds
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Aqueous fixatives caused dry seed tissues to swell; mashed peanuts, crushed to remove oil, swelled even more. Use of anhydrous, organic solvents as vehicles for fixatives enabled maintenance of dimensional stability during fixation of dry seed tissues; even crushed seed tissue did not swell significantly when processed anhydrously. However, anhydrously processed specimens proved difficult to section. The difficulty was due to imperfect permeation of plastic into the seed tissues during embedding. An explanation of why anhydrously processed dry seed tissues are so difficult to embed in plastic is offered.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 176
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 119 (1984), S. 48-54 
    ISSN: 1615-6102
    Schlagwort(e): Electron microscopy ; Marine alga ; Membrane contrast ; Osmium-azole complexes ; X-ray microanalysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Addition of certain heterocyclic nitrogen-carbon compounds to standard osmium tetroxide solutions used as secondary fixative resulted in an enhanced general membrane contrast in cells of the marine algaEmiliania huxleyi (Lohmann) Kamptner. Ultrastructural cell morphology and the contrast distribution were compared between cells treated according to a standard secondary fixation procedure and cells post-fixed when above mentioned heterocyclic compounds were introduced; in both cases some of the ultrathin sections were post-stained. Different compounds were tested: 1,2,4-triazole (TRA), 3-amino-1,2,4-triazole (A-TRA), 5-amino-tetrazole (A-TEA) and 2,4,6-tri-amino-1,3,5-triazine (melamine). The results were interpreted to indicate the possible bonding types arising from interaction of the heterocyclic compounds with osmium tetroxide and with membrane constituents. Interpretations were partly inspired by considerations from coordination chemistry. All above tests which did not include post-staining of thin sections could be performed at alkaline pH, and consequently calcified structures were preserved. The enhanced osmium accumulation at membranes was verified with X-ray microanalysis, which also showed that in the cases where membranes were visibly contrasted, localization of probable sites of intracellular non-crystalline calcium was facilitated.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 177
    ISSN: 1615-6102
    Schlagwort(e): Bauhinia purpurea ; Colloidial gold ; Golgi apparatus ; Immunocytochemistry ; Lectin ; Lowicryl K4M ; Protein body
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The seed lectin of the tree legume,Bauhinia purpurea alba, was localized by electron microscopic immunocytochemistry. The pattern of lectin deposition and site of intracellular localization was examined in mid- to late-maturation seeds. The seed tissue was embedded in Lowicryl K4M, the use of which with seed tissues is discussed. Immunocytochemical labeling was accomplished with colloidal gold coupled to a second antibody. The immunocytochemical reaction was specific and sensitive. Protein bodies, Golgi apparatus and Golgi secretion vesicles were densely labeled. Golgi apparatus was oriented such that Golgi secretion vesicles were in close proximity to the protein bodies. The entire Golgi apparatus was labeled with no concentration gradient across the Golgi stack. These observations indicate that the final site of lectin deposition is the protein body, and that the Golgi apparatus plays an essential role in the deposition process.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 178
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 122 (1984), S. 86-90 
    ISSN: 1615-6102
    Schlagwort(e): Immunocytochemistry ; Non-articulated laticifers ; Articulated laticifers ; Asclepiadaceae
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary sensitive immunocytochemical method for the identification of laticifers has been developed. Frozen sections of various laticifer-bearing plant material, mounted on slides, were first flooded with the IgG fraction of rabbit anti-latex antiserum, prepared using whole latex ofAsclepias syriaca, then flooded with fluorescein-conjugated IgG fraction goat anti-rabbit IgG to visualize laticifers. Positive fluorescence was observed for laticifers in shoots and embryos ofA. syriaca andStapelia bella and embryos ofA. tuberosa. Laticifers did not fluoresce in shoots ofA. tuberosa andEuphorbia tirucalli, in embryos ofE. marginata, or in petioles ofMusa paradisiaca andCichorium intybus. Controls prepared with uninjected rabbit serum were negative (no fluorescence).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 179
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 111 (1982), S. 206-214 
    ISSN: 1615-6102
    Schlagwort(e): Bark beetle ; Sensilla ; Chemoreceptors ; Mechanoreceptors ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The antennal sensilla inI. typographus are almost exclusively confined to the flattened terminal flagellar segment. The sensillar types have distinct distribution patterns in the three areas where they are found. Judging from the ultrastructural characteristics the following functions can be assigned to the sensillar types: chemoreception, single-walled and double-walled sensilla; chemoreception/mechanoreception, terminal-pore sensillum. Moreover there are two types of mechanoreceptors, one of which is connected to a bristle, whereas the other terminates within the cuticle of the flagellar segment.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 180
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 121 (1984), S. 25-33 
    ISSN: 1615-6102
    Schlagwort(e): Immunocytochemistry ; Colloidal gold ; Wheat germ agglutinin ; Lectin ; Cryosections
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The chitin-binding lectin wheat germ agglutinin (WGA) is found at the periphery of wheat embryos, and a similar lectin is present at the root tips of older plants (Mishkind et al. 1982). Although a ferritin-conjugated secondary antibody is adequate for localizing WGA in embryos, native electron-opaque particles make the electron microscope identification of added label equivocal in other wheat tissues. As reported here, however, unambiguous ultrastructural localization of WGA-like lectin in adult wheat roots can be obtained with rabbit anti-WGA followed by colloidal gold-labeled goat anti-rabbit (GAR) IgG. Colloidal gold (CG) was prepared by the reduction of gold chloride with citrate, ascorbate or phosphorous. GAR IgG, prepared from serum by antigen affinity chromatograhy, was adsorbed to the gold particles to produce a stabilized suspension of GAR-CG. Localization was performed on 8–12 μM frozen sections of tissue fixed in 4% paraformaldehyde, 0.3% glutaraldehyde, and 0.75% acrolein in phosphate-buffered saline containing 1M sucrose. Localization with GAR-CG was first compared to that ascertained in embryos using other probes and was then extended to the roots of adult plants. An advantage of the GARCG method is that it permits the visualization of antigen at both the light and electron microscope levels in the same section. At the light level, the anti-WGA-GAR-CG complex appears as a red stain that is localized in specific tissues of embryos and in the caps and outer layers of adult roots. Sections in which lectin was detected at the light microscope level were embedded in plastic and sectioned for subcellular examination. Electron dense gold particles indicative of WGA are found at the periphery of protein bodies in wheat embryos and in vacuoles of the roots of adult plants. Sections incubated with control IgG lack reaction product.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 181
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 104 (1980), S. 193-200 
    ISSN: 1615-6102
    Schlagwort(e): Analytical electron microscopy ; ATPase cytochemistry ; Plasma membrane ; Ricinus communis ; Triticum aestivum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The claim that osmium-containing deposits which lack lead are frequently and incorrectly interpreted as enzymatic reaction products in lead precipitation techniques for ATPase localization in plants is without foundation. Proper controls clearly demonstrate the enzymatic origin of membrane-located deposits and the presence of lead is confirmed by analytical electron microscopy.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 182
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 105 (1980), S. 1-8 
    ISSN: 1615-6102
    Schlagwort(e): Aging ; Chloroplast ; Phytohormones ; Triticum aestivum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Phytohormones like IAA and kinetin inhibit chlorophyll loss during aging of wheat chloroplasts duringin vivo andin vitro. GA, on the other hand, stimulates the pigment degradation during aging of attached leaves in contrast to its senescence inhibiting action in detached leaves and isolated chloroplasts. A shift in optimum concentration of hormone in inhibiting chlorophyll degradation suggests a differential pool size of endogenous hormone regulating aging of chloroplastsin vivo andin vitro. The retardation of chlorophyll loss by kinetin, IAA and GA during aging of chloroplastsin vitro would indicate that the effect of hormones in preventing yellowing of senescing leaves may be mediated through their direct action on chloroplasts.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 183
    Digitale Medien
    Digitale Medien
    Springer
    Protoplasma 105 (1981), S. 333-339 
    ISSN: 1615-6102
    Schlagwort(e): Immunocytochemistry ; Pea seed ; Protein histochemistry ; Storage proteins
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The pea seed storage proteins legumin and vicilin have been localized by electron microscopy using a post-embedding immunocytochemical double-labelling technique. Highly purified antibodies from sheep, specific to legumin and vicilin, were sequentially reacted on sections of pea cotyledon tissue embedded in glycol methacrylate or Spurr's epoxy resin. The sheep antibodies were visualized indirectly by reaction with Staphylococcal Protein A labelled with colloidal gold. Two discrete sizes of colloidal gold particles can be used for simultaneous localization of two antigens. In near mature tissue, the storage proteins are restricted to organelles, called protein bodies. Individual protein bodies contain both legumin and vicilin.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 184
    Digitale Medien
    Digitale Medien
    Springer
    Plant and soil 69 (1982), S. 311-326 
    ISSN: 1573-5036
    Schlagwort(e): Aeration ; Calcium ; Carbon dioxide ; Ethylene ; Nitrate ; Nitrite ; Nitrous oxide ; Oxygen ; Potassium ; Roots ; Triticum aestivum ; Waterlogging ; Wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary We report a study of the mechanism by which the response of plants to waterlogging can be modified by soil temperature. Wheat was grown initially in well-aerated soil in a controlled environment room before the soil was flooded with aerated, deionized water. The soil temperature was maintained constant in the range 6–18°C while the air temperature was at 14°C. Waterlogging damage was greater in plants at the higher soil temperatures when the plants were compared at the same chronological age. However, when compared at the same growth stage, the response to soil temperature was little differenti.e. plants subjected to waterlogging for a long time at low soil temperatures exhibited a similar reduction in growth and other properties as those subjected briefly at higher temperatures. The concentration of dissolved oxygen in the soil solution declined rapidly at all temperatures, being almost zero after 36 h waterlogging. Temperature affected rates of change of the concentrations of dissolved carbon dioxide, ethylene, nitrous oxide, nitrite, nitrate, calcium and potassium. The importance of soil-and plant-determined properties in the waterlogging response of plants at different temperatures are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 185
    Digitale Medien
    Digitale Medien
    Springer
    Plant and soil 76 (1984), S. 127-137 
    ISSN: 1573-5036
    Schlagwort(e): Adenylate pool ; Biomass volume ; CO2 evolution ; Chitin ; DNA ; Electron microscopy ; Enzymes ; Fluorescent antibody ; Fumigation-respiration ; Fungi Histochemistry ; Imunofluorecence ; Jones-Mollison technique ; Microcosms ; Monoclonal antibodies ; Nitrogen ; Nutrients ; Oxygen consumption ; Phosphorus ; Phytotoxins ; Plate counts ; Rhizobium ; Rhizosphere ; Sulphur ; Xenobiotics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary There is an immense literature on biological and biochemical analyses of soils. Such analyses have revealed the enormous richness of species in soil and their vast range of metabolic potentials and ecological diversity. Accordingly, the approaches used to investigate the soil biota and its biochemistry usually have to be modified or adapted depending upon the purpose of the investigation. Studies of micro-organisms in the soil environment, are complicated because microbial cells are commonly attached to surfaces where they live side-by-side with other populations in consortia usually containing different morphological and physiological types. Such assemblages of organisms cannot be described quantitatively using cultural techniques, such as plate counts, which underestimate both cell numbers and viable biomass. The development of more powerful observational and staining techniques has improved our knowledge of the diverse morphological and biochemical composition of soil micro-communities. Such findings have been amplified at a grosser level by laboratory studies with multi-component systems (microcosms) to mimic field situations and to assess the range of biochemical potentials of microbial consortia. But despite notable advances in analytical methods we are still, with a few exceptions, unable to detect or identify those microorganisms which carry out specific biochemical transformations or determine whether particular cells are alive, dormant or dead at the time of observation. Considerable work has been done to define some of the fundamental ecological attributes of microbial assemblages in soil. Productive work on the metabolic activities of the soil microbiota, specially geochemical transformations of C, N, S and P, has been under way for more than a century. But only in more recent years have more sensitive and reproducible analytical methods become available to measure viable biomass in soil. This will enable some insight to be gained into the role that microbial biomass plays as a labile source and sink for plant nutrients.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 186
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 29 (1980), S. 337-346 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; Septoria nodorum ; Leptosphaeria nodorum ; glume blotch ; resistance ; tolerance ; escape ; selection ; selection indexes ; phenotypic correlations ; genotypic correlations ; heritability ; grain yield ; heading date ; plant height ; seed weight ; seed weight %
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary A population of 572 F2 derived F3 lines from six crosses were used to estimate parameters relevant to selection for resistance to Septoria nodorum of wheat. Lines were grown in disease free (fungicide sprayed) and inoculated microplots in 2 replications of a split-plot design in a single environment in 1977. Average yield reduction due to disease was approximately 50%; this was associated with an average septoria score of 50% on the flag leaf, an average septoria score of 42% on the head, and a reduction of 37% in seed weight. Low S. nodorum scores were correlated with late heading date, tall plant height, high grain yield, and high seed weight in diseased plots, and high seed weight % (seed weight in diseased plots expressed as a percentage of seed weight in fungicide sprayed plots). Restricted selection indexes were used to study the relative contributions of disease escape, true resistance, and tolerance to variability in grain yield in diseased plots, seed weight in diseased plots, and seed weight %. True resistance appeared to be the most important factor causing variation in grain yield in diseased plots and seed weight %. Tolerance and escape seemed to be more important for seed weight in diseased plots. Heritabilities of S. nodorum scores on the flag leaf and head were 63% and 52%, respectively. Leaf and head scores could be used most effectively as selection criteria to upgrade resistance in a population before harvest. Selection for high seed weight % slightly reduced yields in disease free plots, although yield in diseased plots and seed weight in diseased plots were increased. However, selection for increased yield or increased seed weight in diseased plots improved yield in disease free plots. It is suggested that direct selection for yield or seed weight in diseased plots is likely to achieve more desirable goals than selection for seed weight %.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 187
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 31 (1982), S. 549-564 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; grain yield ; selection
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Four selection experiments were sown: single-row plots with single row-spacing (≃20 cm), single-row plots with double row spacing (≃40 cm), three-row plots and six-row plots both with single row-spacing (≃20 cm). Selection entries were mimiced by 16 different varieties or advanced breeding lines, which were also sown in a yield trial. Each experiment was laid out as a 4-times replicated randomized block design. Row length was 2 m. Alley borders and border-rows of multiple-row plots were harvested separately to evaluate the effects of different harvesting procedures on the selection efficiency. Removal of alley borders was found to be disadvantageous, since the gain in precision was more than offset by the loss in sampled area. Wide spacing of single-row plots improved the selection efficiency in comparison with normal spaced single-row plots. In multiple-row plots the selection efficiency was not improved by harvesting only the central rows. For gross plot yield (= yield of net plot + yield of alley borders) the differences in selection efficiency between the various selection plot-types were explained on the basis of the genetic variance, the environmental variance and the coefficient of genetic correlation with ‘farm’ yield as determined in the yield trial.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 188
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 32 (1983), S. 217-223 
    ISSN: 1573-5060
    Schlagwort(e): Hexaploid triticale ; Secale cereale ; rye ; Triticum aestivum ; wheat ; heterochromatin ; chromosome association
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary In the hexaploid triticale (× Triticosecale Wittmack) cultivar Rosner chromosome 2R lacks the prominent heterochromatic bands of both telomeres. This modified 2R chromosome is capable of pairing in a high frequency with wheat chromosomes. It is hypothesized that the accumulation of heterochromatin at the telomeres of rye chromosomes may have contributed to the isolation of the wheat and rye genera by inhibiting pairing between wheat and rye chromosomes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 189
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 32 (1983), S. 431-438 
    ISSN: 1573-5060
    Schlagwort(e): Hordeum vulgare ; barley ; Triticum aestivum ; wheat ; T. turgidum ; durum wheat ; X Triticosecale ; triticale ; salt tolerance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Saline soils are typically very patchy in their salinity. The yield of crops growing on them is similarly patchy. This paper argues that because most of the yield from such soils comes from the least saline areas, the best breeding strategy for improving the overall yield of crops growing on them is to select for high yield on non-saline soils. This conclusion derives from comparing the effects that four different breeding goals, namely: (1) a 10% increase in yield on non-saline soils, (ii) a 20% increase in the threshold salinity that first reduces yield, (iii) a doubling of yield at an electrical conductivity of the saturation extract (ECe) of 20 dS/m and (iv) a combination of (i) and (iii), would have on total yield. The effects of achieving these goals in barley, common wheat, durum wheat and triticale in fields exhibiting different salinities are predicted from actual yields of these species grown on different salinities in the field.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 190
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 32 (1983), S. 617-624 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; kernel color ; protein content ; inheritance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Utilization of high-protein hard red wheat germplasm in breeding high-protein hard white winter wheats for the U.S. Great Plains raised concern regarding possible genetic relationships between kernel color and protein content. Segregating F3 and F4 populations from reciprocal crosses and backcrosses involving high-protein hard red winter wheat cultivar Plainsman V and normal-protein hard white winter wheat line KS75216 were examined. Nonsignificant regression and correlation coefficients in the F3 generations of KS75216/Plainsman V, KS75216//KS75216/Plainsman V and Plainsman V//KS75216/Plainsman V indicated the absence of genetic relationships between kernel color and protein content. Therefore, despite the presence of genes for protein content and kernel color on the same chromosomes (3A, 3B and 3D), kernel color and protein content appeared as independent traits. A small but significant negative relationship between white kernel color and high protein in Plainsman V/KS75216 was attributable to the possible presence of alien genetic material in the parentage of Plainsman V. Chi-square tests indicated that Plainsman V is a mixture of genotypes for kernel color; most genotypes carry two dominant genes for red color and a few carry one or three. Genetic control of grain protein appeared to be complex. Partial dominance for high protein was indicated in the F3 generation but a generally continuous distribution and transgressive segregation also suggested other genes functioned additively. Heritability estimates by parent-offspring (F3-F4) regression were sufficiently high to ensure genetic progress in the selection of high-protein lines in the red x white wheat crosses. We concluded that development of high-protein cultivars is as feasible for white wheats as for red wheats.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 191
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 32 (1983), S. 299-310 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; bread wheat ; ear colour ; glume colour ; genetics ; linkage ; chromosomal location ; geographical distribution ; homeoallelic genes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary A summary of the brown ear character of bread wheat is presented. In most varieties this character is conditioned by a (semi)dominant gene identified as Rg on 1BS. This gene seems to be widespread, from the viewpoint of evolution, probably because it is an ‘old’ gene. There are no indications that the presence of the gene and hence the presence of a brown ear is advantageous or disadvantageous to the carrier wheat plant. Some linkage relations are described. More research is needed to establish whether all varieties with one gene for brown ear carry Rg, to investigate the varieties with a non-monogenic genetic system and to identify more associations between brown ear and other characters. It should also further be investigated whether within T. spelta another gene for brown ear is present and, if so, whether this gene is on chromosome 1AS and linked to Hgl, the gene for hairy glume.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 192
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 32 (1983), S. 743-748 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; plant physiology ; plant breeding ; Australia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Major changes in the behaviour of the Australian wheat crop over the last one hundred years have been associated with three major gene groupings. The significance of major genes in monitoring response to vernalization, photoperiod and gibberellin, reveals a more optimistic future for breeding programmes where simple genetic and physiologic studies are integrated within those programmes. A revised classification of growth habit is presented in the appendix.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 193
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 33 (1984), S. 81-89 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; grain yield ; phosphate response ; height ; harvest index
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The response to phosphate fertilizer by modern wheat genotypes was examined in the field under natural rainfall in three seasons. Models were developed which show that grain yield was positively correlated with biological yield and harvest index. In one of the seasons, which was relatively dry, shorter statured wheats gave higher yields at each level of applied phosphate. Higher levels of phosphate tended to offset the reduction in yield associated with late heading and the importance of biological yield on grain yield. The genotypes which produced the largest number of grains m-2 produced the highest yields. Implications for plant breeding programs are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 194
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 33 (1984), S. 107-112 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; male sterility ; meiotic analyses ; gene mapping
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Genetic and cytogenetic studies were done on a male sterile mutant of the wheat variety ‘Probus’. Association of the 4A chromosome carrying the ms gene was studied in the F1 of the male sterile ‘Probus’ with ‘Chinese Spring’ ditelo 4AS, with ‘Transec’ and with line ‘T4AS-DRS’ respectively. The presumption that the genetic male sterility of the mutant was due to a terminal deletion of the short arm of chromosome 4A could be confirmed. Linkage studies showed that the ms gene was at 17 map units from the dwarfing gene (Rht3) of ‘Minister dwarf’. This allows selection of short male sterile plants at the seedling stage.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 195
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; glutenin ; high molecular-weight subunits of glutenin ; SDS-PAGE ; 1R(1B) substitution identification ; 1BL/1RS translocation identification ; bread-making quality
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The high-molecular-weight subunits of glutenin from wheat 1R(1B) substitution and 1BL/1RS translocation lines were fractionated by SDS-PAGE. Two new subunits denoted R1 and R2 were characterized in 1R(1B) substitution, but not in 1BL/1RS translocation lines. R1 and R2 were proved to be rye proteins by 2d electrophoresis (NEPHGE x SDS-PAGE). In contrast to literature citations it was demonstrated that the cultivar Winnetou is a 1R(1B) substitution line and the cultivars Clement and Mildress both are 1BL/1RS translocation lines.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 196
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; common wheat ; Puccinia striiformis ; yellow rust ; stripe rust ; resistance ; genetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Three lines derived from the old ‘dirty’ Dutch land variety Gelderse Ris were resistant against race 66(70)EO(16) of yellow rust. It was found that this resistance was conditioned by one recessive gene provisionally coded yrGR.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 197
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 33 (1984), S. 757-767 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; bread wheat ; Triticum durum ; durum wheat ; water stress ; photosynthesis ; stomatal resistance ; leaf water potential ; water efficiency ; breeding
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The responses of six wheat genotypes to water stress were analysed. Soil moisture (H), leaf water potential (Ψw), photosynthesis (PN), stomatal resistance (rs) and transpiration (T) were measured during a water stress. The genotypes investigated differed in their stress avoidance (Ψw-H relationship) and their stress tolerance (PN-Ψw and rs-Ψw relationships). The most important differences observed concern the mechanisms of tolerance at low leaf water potential: two varieties, Haurani 27 and Baalback, can then maintain a high photosynthetic activity. These observations are in agreement with the drought resistance characteristics already known for these genotypes. Possible applications to wheat breeding are considered
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 198
    ISSN: 1573-5060
    Schlagwort(e): Triticum dicoccoides ; wild emmer ; Triticum aestivum ; bread wheat ; nitrogen uptake ; plant nitrogen distribution ; translocation efficiency ; harvest index ; domestication ; evolution ; yield components ; grain protein
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Differences were found in total nitrogen uptake and its pattern of distribution in the main tiller amongst five lines of wild tetraploid wheat (Triticum turgidum dicoccoides) and between it and two hexaploid wheats (Triticum aestivum) under low (48 ppm) and higher (240 ppm) levels of soil nitrogen. Under the low soil nitrogen level the hexaploids had higher amounts of total nitrogen in the main tiller than the dicoccoides lines, but under the higher soil nitrogen level, three of the dicoccoides lines had significantly (P〈0.01) higher, and the other two lines, similar amounts as the hexaploids. The total amount of grain nitrogen in the hexaploids was significantly (P〈0.01) higher than the five dicoccoides under the low nitrogen soil level but under the higher level, two of the dicoccoides lines had similar amounts as one of the hexaploids (cv. Bencubbin) but significantly (P〈0.01) lower than the other (cv. Argentine IX). The efficiency of nitrogen translocation to the grain was significantly (P〈0.01) lower in a primitive, compared with four cereal forms of dicoccoides under both low and high levels of soil nitrogen. The cereal forms of dicoccoides, while similar in nitrogen translocation efficiency under low soil nitrogen as the lower translocation efficiency hexaploid (cv. Bencubbin), were significantly (P〈0.01) and substantially lower than it under the higher soil nitrogen level.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 199
    Digitale Medien
    Digitale Medien
    Springer
    Plant and soil 74 (1983), S. 369-377 
    ISSN: 1573-5036
    Schlagwort(e): Acetic acid ; Inhibition ; Wheat growth ; Tillering ; Root growth ; Triticum aestivum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Studies were conducted to determine the effect of and duration of the effect of alliphatic acids on winter wheat (Triticum aestivum L.) seedling root growth, shoot growth, and tillering. Winter wheat seedlings grown in contact with unbuffered solutions of 2 mM or greater acetic or 0.5 mM or greater propionic or butyric acid for 3 days showed decreased root and, in general, shoot growth. Buffering the medium partially alleviated the problem. Removing the seedling from the acid medium and growing it in a nutrient medium resulted in accelerated root growth, compared with the control, while shoot growth was permanently inhibited during this study. Seedling wheat, grown with one root in contact with concentrations of acetic acid ranging from 0–16 mM and the other roots in aliphatic acid-free medium, grew at the same rate as the control. Seedling wheat grown for 3 days in 2 and 4 mM acetic acid medium showed a more rapid formation of the first stem tiller (T1) than did the control. Concentrations of 6 and 8 mM acetic acid appeared to delay T1 tiller formation through the first 18 days after germination, while only 10 mM acetic acid reduced T1 tiller formation by 30% 20 days after germination. The second stem tiller (T2) was not affected by previous exposure to acetic acid. The results of these laboratory studies indicate that short-term exposure of seedling winter wheat to short-chain aliphatic acids can result in permanent shoot and tiller damage and not in permanent root damage as previously thought. These results could explain the poor performance of no-till seeded winter wheat when growing through heavy crop residues that are producing shortchain aliphatic acids during decomposition.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 200
    Digitale Medien
    Digitale Medien
    Springer
    Plant and soil 68 (1982), S. 69-74 
    ISSN: 1573-5036
    Schlagwort(e): Azotobacter ; chroococeum ; Derxia ; gumnosa ; Klebsiella ; Nitrogen ; fixation ; Phyllosphere ; Triticum aestivum ; Wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Five highly active N2-fixing strains of Klebsiella isolated from the phyllosphere of tropical plants, KUPBR1, KUPBR2, KUPM, KUP4 and KUP6 along withAzotobacter vinelandii OP,A. chroococcum G40 andDerxia gumnosa were sprayed on the foliage of a high yielding wheat cultivar, Kalyansona. The strains of Klebsiella enhanced dry wt., chrorophyll and nitrogen content, and 1000 grain weight. Grain yield in inoculated plants varied between 19.9 and 25.09 quintals ha−1 against 24.34 quintals with urea. Best results were obtained with KUP4 which when applied at half dose was as effective as 52.5 kg Urea-N ha−1. Azotobacter and Derxia only slightly improved growth and nitrogen content of grain or straw.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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