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  • Rat  (44)
  • Angiosperms  (27)
  • Springer  (71)
  • American Chemical Society (ACS)
  • 1980-1984  (71)
  • 1981  (71)
Collection
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  • Springer  (71)
  • American Chemical Society (ACS)
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  • 1980-1984  (71)
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  • 1
    Electronic Resource
    Electronic Resource
    Effect of vitamin D deficiency on urinary excretion of connective tissue derivatives (hydroxyproline and glycosaminoglycans) in rats (1981)
    Springer
    Calcified tissue international 33 (1981), S. 177-180 
    Details
    ISSN: 1432-0827
    Keywords: Connective Tissue ; Vitamin D deficiency ; Hydroxyproline excretion ; Glycosaminoglycan excretion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The urinary excretion of two connective tissue metabolites was studied in both control and vitamin D deficient rats. Hydroxyproline (HyPRO) excretion was determined after 2, 13 and 22 months (experiment I). It decreased with aging in animals receiving the control diet. On the contrary, this excretion increased as a function of age in vitamin D deficient animals. At the age of 22 months, HyPRO excretion was respectively 31 and 1708 µg a day in control and deficient animals. HyPRO and glycosaminoglycans (GAG) excretion was measured on a group of both control and vitamin D deficient rats at the age of 21 months (experiment II). These results confirm the high excretion of HyPRO in deficient animals. On the contrary, the GAG excretion was higher in control animals than in deficient ones, the mean excretion being respectively 412 and 234 µg a day.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02409432
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  • 2
    Electronic Resource
    Electronic Resource
    Effects of chronic protein deficiency on skeletal development of young rats (1981)
    Springer
    Calcified tissue international 33 (1981), S. 223-231 
    Details
    ISSN: 1432-0827
    Keywords: Protein deficiency ; Bone formation ; Skeletal development ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Protein deficiency was produced by freely feeding young rats a 1% lactalbumin diet for 12 weeks in order to study the effects of protein-calorie malnutrition on skeletal development. During the experiment the food and caloric intake and weight of the experimental animals decreased, while those parameters of the control animals progressively increased. However, when gross caloric intake was expressed as a function of the metabolic size of the animal, the caloric consumption was similar for both groups of animals. The protein-deficient animals exhibited micro-radiographic and histological features of an abnormal pattern of endochondral bone formation. Appositional bone growth, as determined by the daily appositional rate and the percentage of endosteal surfaces undergoing active bone formation, was significantly decreased in these animals, as was the percentage of periosteal surfaces exhibiting resorption. Both chemical analyses of the whole bone and electron probe microanalysis in the specific area of actively calcifying bone revealed no significant differences between the mineral content of control and protein-deficient animals. This study distinguishes the effects of protein deficiency from that of combined protein-calorie deprivation and demonstrates that the abnormal skeletal development observed was the result of a decrease in the quantity of bone formed rather than an altered mineral content.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02409441
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  • 3
    Electronic Resource
    Electronic Resource
    Cytochemical studies on the ferritin-containing vesicles of the rat incisor ameloblasts with special reference to the acid phosphatase activity (1981)
    Springer
    Calcified tissue international 33 (1981), S. 51-55 
    Details
    ISSN: 1432-0827
    Keywords: Rat ; Incisor ; Amelogenesis ; Acid phosphatase ; Ferritin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Acid phosphatase was localized in rat incisor ameloblasts without prior decalcification. Whenβ-glycerophosphate was used as the substrate, an intense reaction was observed in the supranuclear region of the secretory ameloblasts. But the reaction was dramatically reduced at the transitional stage and was very weak in the maturation ameloblasts. Whenp-nitrophenylphosphate was the substrate, the reaction product was consistently seen in the Golgi cisternae and the vesicular components of the ameloblasts at all stages of enamel development. These observations suggest that there are two acid phosphatases in ameloblasts. One is in the secretory ameloblasts and the other in the transition and maturation ameloblasts. X-ray micro-analyses for Fe and Pb showed that Fe and acid phosphatase were in the ferritin-containing vesicles at the later stage of enamel maturation. This evidence suggests that ferritin is digested in these vesicles for the release of the Fe pigment to the enamel. An increase in the number of intercellular bridges between ameloblasts was correlated with the dramatic decrease in height of ameloblasts at the pigment release stage. The ameloblast membranes were acid phosphatase positive at the intercellular bridges whenp-nitrophenylphosphate was the substrate. This activity may be involved in the reduction in the surface area of the ameloblast membranes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02409412
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  • 4
    Electronic Resource
    Electronic Resource
    Changes in oxytocin content in the magnocellular neurons of the rat hypothalamus following water deprivation or estrogen treatment (1981)
    Springer
    Cell & tissue research 216 (1981), S. 47-55 
    Details
    ISSN: 1432-0878
    Keywords: Oxytocin ; Paraventricular nucleus ; Supraoptic nucleus ; Anterior commissural nucleus ; Immunohistology ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effect of water deprivation or estrogen treatment on the oxytocin content of rat hypothalamic cells was examined using a quantitative immunohistological technique. Oxytocin-containing cells were visualized using the immunoperoxidase technique of Sternberger and a primary antiserum directed against oxytocin. The optical density of the darkest 3.2 μm diameter spot in the cytoplasm of a cell was used as a measure of the oxytocin content of that cell. Water deprivation produced a significant decrease in anti-oxytocin staining in the anterior commissural nucleus of males and females. There was a similar decrease in the paraventricular nucleus of males, but not in the paraventricular nucleus of females or the supraoptic nucleus of either males or females. Estrogen treatment of ovariectomized female rats produced a fall in anti-oxytocin staining in the anterior commissural, but not paraventricular or supraoptic nuclei.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234544
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  • 5
    Electronic Resource
    Electronic Resource
    Correlative ontogenetic development of catecholamine- and LHRH-containing nerve endings in the median eminence of the rat (1981)
    Springer
    Cell & tissue research 216 (1981), S. 31-38 
    Details
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Ontogeny ; LHRH ; Catecholamines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ontogenetic development of catecholamine (CA)-and LHRH-containing nerve endings in the median eminence of the rat was investigated by combining fluorescence histochemistry and immunohistochemistry in the same tissue section. LHRH-terminals appeared earlier than CA-terminals and were already detectable in the lateral part of the external layer of the central ME on the first day after birth. CA-nerve endings were first seen in a corresponding region of the ME on the seventh postnatal day. At this stage both types of terminals showed the earliest manifestation of a correlative pattern of their distribution. Subsequently the development of both types of nerve endings proceeded rapidly, and at 14 days their distribution pattern corresponded to that in adult animals. The authors conclude that at this stage the CA-neurons play a constant and significant role in the release of LHRH into the portal capillaries. The correlation between both types of nerve endings and the ontogenetic development of the capillary plexuses of the hypophysial portal system is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234542
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  • 6
    Electronic Resource
    Electronic Resource
    Effects of norepinephrine and dibutyryl adenosine 3′, 5′-cyclic monophosphate on the ultrastructure of pineal cells in monolayer culture (1981)
    Springer
    Cell & tissue research 216 (1981), S. 181-191 
    Details
    ISSN: 1432-0878
    Keywords: Pineal gland ; Monolayer culture ; N-acetyl transferase ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary To determine how neural influences control the function of the pineal gland, morphological and biochemical relationships after pharmacological treatment have been studied in rat pineal cells in monolayer cultures. Norepinephrine (NE) and dibutyryl cyclic 3′,5′-adenosine monophosphate (dBcAMP) treatment of cells that had been in culture for 5 and 21 days produced a stimulation in the enzyme activity of serotonin N-acetyl transferase, an enzyme important in indole synthesis. NE and dBcAMP also produced morphological changes which were dependent on the time of cells in culture. When 5 day-cultures were treated with NE and dBcAMP, light and dark cells were noted and endoplasmic reticulum increased and became more organized. Only dBcAMP treatment at 5 days produced an increase in dense granules and an elongation of cytoplasmic processes. Treatment of 21 day-cultures with dBcAMP also produced an increase in cytoplasmic processes while treatment with NE produced an increase in the synaptic ribbons and clear vesicles within the processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234553
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  • 7
    Electronic Resource
    Electronic Resource
    The effect of a liquid elemental diet on cell proliferation in the colon of rats (1981)
    Springer
    Cell & tissue research 216 (1981), S. 221-225 
    Details
    ISSN: 1432-0878
    Keywords: Diet ; DNA synthesis ; Cell renewal ; Colon ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A liquid elemental diet (Vivonex) was given to rats for 6 days while control animals received a normal diet. At the end of the experiment each animal received one intraperitoneal injection of tritiated thvmidine at 8a.m. Animals from each group were killed hourly during the first 24h after the injection and the proliferative activity was studied by autoradiography of the mucosa of the colon using the labeled mitoses-wave method. The epithelial cell proliferation was significantly decreased in the colon of the Vivonex-fed animals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234557
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  • 8
    Electronic Resource
    Electronic Resource
    Cerebellar intranuclear inclusions in chronically alcoholized rats (1981)
    Springer
    Cell & tissue research 216 (1981), S. 227-230 
    Details
    ISSN: 1432-0878
    Keywords: Cerebellum ; Nuclear inclusions ; Alcohol ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Nuclear rods and sheets are described in neurons from the cerebellar cortex of rats alcoholized through ingestion of a 20 % aqueous ethanol solution over a period of 90 and 180 days. An eventual relationship between these nuclear inclusions and alcoholization is advanced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00234558
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  • 9
    Electronic Resource
    Electronic Resource
    Growth of aortic vascular smooth muscle cells in lowered oxygen tension (1981)
    Springer
    Cell & tissue research 216 (1981), S. 591-602 
    Details
    ISSN: 1432-0878
    Keywords: Vascular smooth muscle ; Tissue culture ; Hypoxia ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Primary cultures of vascular smooth muscle cells, isolated from rat aorta, were grown under normoxic (20% O2) and mildly hypoxic (5 % O2) conditions. Cells from both conditions were compared for growth characteristics, morphology, protein synthesis, lysosomal enzyme activity, and oxygen consumption. In no case was a consistently significant difference observed. These observations indicate that these cells can adapt or are adapted to mildly hypoxic conditions. Moreover, these results may indicate that the culture of vascular smooth muscle cells in mild hypoxia represents a closer approximation of in vivo growth conditions for these cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00238654
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  • 10
    Electronic Resource
    Electronic Resource
    Role of estrogen and androgen in maintaining the preovulatory follicle (1981)
    Springer
    Cell & tissue research 216 (1981), S. 615-624 
    Details
    ISSN: 1432-0878
    Keywords: Rat ; Preovulatory follicle ; Ultrastructure ; Estrogen ; Androgen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of Nitromifene citrate (CI 628), an antiestrogen, and Flutamide, an antiandrogen, on the ultrastructure and viability of the preovulatory follicle and granulosa cells were examined both in vivo and in vitro. In vivo administration of either antihormone induced degeneration within the granulosa cells. In some of the affected granulosa cells, the nuclear material was condensed while the cytoplasm and associated organelles were unaltered. In others, the density of the cytoplasm was reduced, the smooth endoplasmic reticulum was dilated but the nucleus remained unaltered. In vitro, either antihormone reduced granulosa-cell viability but the granulosa cells were twenty times more sensitive to CI 628 than to Flutamide. In addition, exposure to CI 628 induced nuclear condensation without affecting the cytoplasm, while Flutamide induced the deterioration of the cytoplasm without altering the nucleus. These observations suggest that: (1) both estrogen and androgens control the viability of the granulosa cells and thereby the follicle, (2) the action of estrogen and androgen is mediated through receptors within the granulosa cells since these antihormones prevent the nuclear uptake of their respective hormone, (3) the granulosa cells of preovulatory follicles appear to be more dependent on estrogen than on androgen, and (4) each steroid appears to have a specific role in maintaining the granulosa cell; estrogens control the integrity of the nucleus while androgens preserve the cytoplasmic organization of the granulosa cell.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00238656
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  • 11
    Electronic Resource
    Electronic Resource
    Catecholamine-storing cells in the adrenal medulla of the pre- and postnatal rat (1981)
    Springer
    Cell & tissue research 217 (1981), S. 155-170 
    Details
    ISSN: 1432-0878
    Keywords: Adrenal medulla ; Development ; Acetylcholinesterase ; Small granule cells ; Ultramorphology ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of the rat adrenal medulla was studied at the ultrastructural level with particular emphasis placed on early discrimination of different catecholamine-storing cells. The first granule-containing cells, phaeochromoblasts, were seen at day 15 of gestation migrating into the anlage of the cortex. These cells were characterized by a few small granules (80–120 nm in diameter) and a high nuclear to cytoplasmic ratio. Presumably due to differentiation into chromaffin cells, they were no longer present after the eighth postnatal day. Maturation of phaeochromoblasts was indicated by an increase in number and size of their storage granules and a decrease in the nuclear to cytoplasmic ratio. Noradrenaline and adrenaline cell types were first clearly discernible at day 21 of gestation. Another cell type, a giant cell, was also recognized at this stage. In the adult animal, noradrenaline, two morphologically different types of adrenaline, and small granule-containing cells were observed. By applying acetylcholinesterase histochemistry, it was found that at day 17 of gestation a small population of granule-storing cells showed strong positive staining in the endoplasmic reticulum. In the adult animal this cell type was further characterized by small-storage granules. Other chromaffin cells began to show weak staining within the endoplasmic reticulum at day 19 of gestation. This staining appeared more frequently within adrenaline than noradrenaline cells. However, even in the adult animal many cells of both types were completely negative. It is concluded that acetylcholinesterase histochemistry is a useful method for early discrimination of small granule-containing cells in the developing rat adrenal medulla.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233834
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  • 12
    Electronic Resource
    Electronic Resource
    Terminal sprouting in rat sternocostalis muscle following partial denervation (1981)
    Springer
    Cell & tissue research 217 (1981), S. 189-198 
    Details
    ISSN: 1432-0878
    Keywords: Rat ; Sternocostalis muscle ; Partial denervation ; Motor neuron sprouting
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The sternocostalis muscle of the rat was examined at one to five days after partial denervation and levels of terminal sprouting were assessed. The removal of one intercostal nerve caused localised degeneration which did not extend more than a few muscle fibres deep into the field of distribution of the adjacent nerve. Terminal sprouting was clearly seen at 24 h after operation and did not appear to develop further up to five days. There was no difference in the sprouting responses to section of either intercostal nerve 2, 4 or 5. There was, however, a decrease in the response with increasing distance from the cut nerve. No sprouting response was observed in the contralateral muscle. Comparison of sprouting levels of B and C type end plates revealed a greater percentage of C type end plates with sprouts. However, the response of B type end plates, considered in relation to the levels of spontaneous sprouting, was greater than that of C type end plates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233837
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  • 13
    Electronic Resource
    Electronic Resource
    Effects of tunicamycin on the hypothalamo-neurohypophysial system of the rat (1981)
    Springer
    Cell & tissue research 217 (1981), S. 199-210 
    Details
    ISSN: 1432-0878
    Keywords: Hypothalamus ; Neurohypophysis ; Neurophysin ; Secretion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Intracisternal injections of tunicamycin, an inhibitor of glycosylation, decreased the incorporation of [35S]cysteine into the neurophysins in the rat neurohypophysis. Histochemical and immunocytochemical studies showed that there was no concomitant decrease in the amount of secretory product in the perikarya of the hypothalamo-neurohypophysial neurones. Indeed there was an increase, although this was not associated with neurosecretory granules as judged electron-microscopically. Tunicamycin led to the formation of socalled “colloid droplets” which were immunopositive and of which the ultrastructural correlates appeared to be product-filled dilatations of the rough endoplasmic reticulum. The observations are interpreted to suggest that glycosylation plays a rôle in the packaging of secretory material in the hypothalamo-neurohypophysial system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233838
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  • 14
    Electronic Resource
    Electronic Resource
    Interrelations between neural elements and tanycytes during the perinatal period of the rat (1981)
    Springer
    Cell & tissue research 215 (1981), S. 635-641 
    Details
    ISSN: 1432-0878
    Keywords: Hypothalamo-hypophysial system ; Rat ; Supraependymal axons ; Ontogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The present study has utilized a correlative scanning-transmission electron microscopic technique to examine interrelations between neural elements and differentiated tanycytes and to identify supraependymal cells in the ventral region of the 3rd ventricle during the perinatal period in the rat. From the 18th day of fetal life monoaminergic and/or peptidergic axons penetrate into the ventricle between the tanycytes. After birth, they form an extensive network covering the surface of the infundibular recess. The axons possess morphological characteristics suggestive of neurohormone secretion. From the 20th day of prenatal life subependymal axons begin to “innervate” the tanycytes. Supraependymal cells differ in their shape and ultrastructure, but all of them bear resemblance to macrophages, as they contain numerous lysosomes and phagosome-like bodies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233537
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  • 15
    Electronic Resource
    Electronic Resource
    Ultrastructural study of electrophysiologically identified neurones in the paraventricular nucleus of the rat (1981)
    Springer
    Cell & tissue research 216 (1981), S. 503-512 
    Details
    ISSN: 1432-0878
    Keywords: Paraventricular neurones ; Alcian-blue labelling ; Ultrastructure ; Electrophysiology ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural characterization of electrophysiologically identified neurones of the rat paraventricular hypothalamic nucleus was performed with extracellular labelling technique. The extracellularly recorded neurones are labelled with an electrophoretic deposit of alcian blue contained in the recording micropipette. The neurone thus labelled takes on a dark and shrunken appearance which enables its detection among neighbouring cells without, however, concealing its main morphological characteristics. 1) Spontaneously firing neurones, invaded by an antidromic action potential elicited by electrical stimulation of the neurohypophysis, were identified as magnocellular cells containing dense-cored vesicles of 200–250 nm in diameter. Dense-cored vesicles were not found in the antidromically activated neurones devoid of spontaneous activity. 2) Trans-synaptically activated neurones in the PVN or in its dorso-lateral edge were small cells devoid of dense secretory vesicles. 3) PV neurones in which neurohypophysial stimulation evoked no response, contained small, dense vesicles (100 nm in diameter) comparable with those found in parvocellular peptidergic neurones.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00238647
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  • 16
    Electronic Resource
    Electronic Resource
    Morphological studies on neuroglia (1981)
    Springer
    Cell & tissue research 216 (1981), S. 569-580 
    Details
    ISSN: 1432-0878
    Keywords: Glial response ; Chemical lesion ; Kainic acid ; Hippocampus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cellular response of non-neuronal elements of the pyramidal cell layer of the rat hippocampus, especially the area CA 3, was observed electron microscopically following destruction of this formation by means of intraventricular administration of kainic acid (KA). The neuroglial cell types responding to the KA-induced lesion included astrocytes and the “microglia-like reactive cells”. In addition, numerous brain macrophages appeared in the damaged area CA 3. Oligodendrocytes and pericytes revealed no morphological changes. Swollen astrocytes were seen in the KA-induced lesion during the early stage. Glial filaments gradually developed in the soma and cell processes of these cells. Brain macrophages were seen in the KA-induced lesion during the early stage; they gradually decreased in number with time. Numerous small cells displaying a dark nucleus appeared in the damaged area CA 3 during the first two days after the KA-administration, and gradually increased in number. During the later stage this cell type could hardly be distinguished from the intrinsic microglial cells. It is open to discussion whether this cell type originates from the intrinsic microglial cells or from the hematogenic monocytes; therefore it is designated as “microglia-like reactive cell” in the present study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00238652
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  • 17
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    Biosystematic studies onCapsella bursa-pastoris (Brassicaceae): Enzyme polymorphism in natural populations (1981)
    Springer
    Plant systematics and evolution 137 (1981), S. 73-94 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Brassicaceae ; Capsella bursa-pastoris ; Isoenzyme polymorphism ; population analyses ; geographic variation ; heterozygosity ; breeding system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The genetic variability of natural populations ofCapsella bursapastoris in North- and Middle-Europe has been estimated by means of enzyme assays. Zymograms of 81 populations have been developed. 17 loci could be identified, and 8 of them can be heterozygous. Genetic variability is greater between populations than within. No correlation between actual population sizes and genetic heterogeneity could be detected. Some electromorphs shift their frequencies proportionally to increasing adversity of climatic conditions, some appear to be constant over the whole area, and others are characterized by an apparently irregular variation pattern. Marginal populations comprise a significantly higher proportion of heterozygous plants than central ones. Apart from this clinal variation pattern, a mosaic pattern, strongly related to habitat conditions, was observed: genetic heterogeneity is greater in more intensively disturbed sites. The pattern of genetic variation in natural populations ofCapsella bursa-pastoris is rather highly influenced by the breeding system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00983207
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  • 18
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    The breeding system ofEmblingia (Emblingiaceae) (1981)
    Springer
    Plant systematics and evolution 137 (1981), S. 63-65 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Emblingia ; Emblingiaceae ; Sapindaceae ; Dodonaea ; Stylobasidaceae ; Stylobasium ; Gyrostemonaceae ; Anemophily ; entomophily ; autogamy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Emblingia is a short lived fire weed with a highly autogamous breeding system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00983205
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  • 19
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    Vergleichende cytotaxonomische Untersuchungen anRanunculus seguieri und der Artengruppe desR. alpestris (Ranunculaceae) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 47-60 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Ranunculaceae ; Ranunculus seguieri ; R. alpestris ; R. traunfellneri ; R. bilobus ; R. crenatus ; Relationship betweenR. seguieri andR. alpestris s. lat.: morphology ; crossing experiments ; chromosome numbers ; karyotypes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Morphological and cytological investigations as well as crossing experiments were carried out withRanunculus seguieri Vill. and 4 species of theRanunculus alpestris L. group (R. alpestris L.,R. traunfellneri Hoppe,R. bilobus Bertol.,R. crenatus Waldst. & Kit.). ForR. seguieri andR. alpestris, localities and distribution are given in addition to extensive diagnoses. A key to the species includes morphological characteristics and distribution data forR. traunfellneri, R. bilobus, andR. crenatus. New diagnostic characters are described. Crossing experiments betweenR. seguieri and the species of theR. alpestris group were unsuccessful. All 5 species have a chromosome number of 2n = 16, the record forR. bilobus is new. There is no statistically significant difference between the karyotypes ofR. seguieri andR. alpestris s. str. Nevertheless, according to morphological evidence and crossing experiments,R. seguieri is not closely related to theR. alpestris group.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00984608
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  • 20
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    A chemotaxonomical study of someBoraginaceae: pyrrolizidine alkaloids and phenolic compounds (1981)
    Springer
    Plant systematics and evolution 137 (1981), S. 127-134 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Boraginaceae ; Pyrrolizidine alkaloids ; phenolic compounds ; chemotaxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract By means of thin layer chromatography pyrrolizidine alkaloids and phenolic compounds in some members of the familyBoraginaceae, subfamiliesHeliotropioideae andBoraginoideae, were studied. FromOmphalodes verna a main alkaloid was isolated with an isoretronecanol (or stereoisomeric) nucleus. The chemotaxonomical model ofTétényi forBoraginaceae based on fatty acids is generally supported, but relationships betweenHeliotropioideae andCynoglosseae appear to be closer, suggesting parallel developments from common ancesters.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00983210
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  • 21
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    Embryology ofEriocaulon setaceum (Eriocaulaceae) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 175-188 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Eriocaulaceae ; Eriocaulon setaceum ; Embryology ; systematics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Eriocaulon setaceum can be characterized by: young microsporangium wall with epidermis, endothecium (with fibrous thickenings), and glandular tapetum (uninucleate cells); pollen grains 3-celled, spiraperturate; embryo sac development according to the Polygonum type and with antipodal cyst; endosperm nuclear; embryo small, with incipient differentiation into cotyledonary and epicotylary loci; seed coat mainly from the inner layers of the integuments; pericarp 2-layered and membranous. Embryologically, theEriocaulaceae are nearer to theXyridaceae than to otherFarinosae. Their elevation to the rank of an order,Eriocaulales, therefore appears justified.
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    Microgeographic edaphic differentiation in allozyme polymorphisms of wild barley (Hordeum spontaneum, Poaceae) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 287-292 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Poaceae ; Hordeum spontaneum ; Allozymes ; microgeographic differentiation ; population genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Allozymic variation in proteins encoded by 22 loci was analyzed electrophoretically in 278 individual plants of wild barley,Hordeum spontaneum, the progenitor of cultivated barley, in four 100 meter transects, in Israel, each equally subdivided into basalt and terra rossa soil types. Significant differentiation according to soil was found in 9 alleles. Our results suggest that allozyme polymorphisms in wild barley are at least partly adaptive, and differentiate by edaphic natural selection rather than by stochastic processes, and/or neutrality of allozymic variants.
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    Genetic variation inSolanum pennellii: Comparisons with two other sympatric tomato species (1981)
    Springer
    Plant systematics and evolution 139 (1981), S. 11-45 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Solanaceae ; Lycopersicon ; Solanum pennellii ; Allozymes ; electrophoresis ; isozymes ; mating systems ; self-incompatibility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Genetic variation—primarily in 19 genetic loci of seven enzyme systems—was analyzed in accessions from various parts of the geographic range ofSolanum pennellii, which according to all tested biosystematic criteria behaves like a species ofLycopersicon. In comparison with the largely sympatricL. hirsutum andL. pimpinellifolium, this species exhibits the same trends of reduced allogamy and decreased genetic variation toward the north and south margins of its distribution, though to a much lesser degree; it does not exhibit their trends toward smaller flower size in the same peripheral regions. All three species agree to a considerable extent in the ranking of their tested loci in respect to degree of variablility; however, overall polymorphy is highest inS. pennellii. Except for the appearance of self-compatibility at its southernmost margin,S. pennellii is exclusively and rigidly self-incompatible. Alleles are distributed much more uniformly over the range than in the previously mentioned species, marginal and internal endemic mutants being much less abundant. A marked geographic disagreement is evident in regions of high and low variation. These differences in patterns of genetic variability are reconciled in terms of observed differences in mating systems, probable age of distributions, and adaptive strategies.
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    Eine neueTillandsia-Art aus Südmexico:T. kolbii (Bromeliaceae) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 259-262 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Bromeliaceae ; Tillandsia subgen.Allardtia ; T. kolbii ; spec. nova ; Flora of Mexico
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A new species ofTillandsia is described and discussed in regard to related species.
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    Ultrastructure of the stylar canal cells ofCitrus limon (Rutaceae) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 263-274 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Rutaceae ; Citrus limon ; Style ; canal cells ; canal filling substance ; ultrastructure ; anatomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The ultrastructure of the canal cells and the canal filling substance ofCitrus limon have been studied. At maturity the canal cells are very rich in cytoplasm. Their inner tangential walls lining the canal are much thickened and formed by two layers: the outer corresponds to the original wall, the inner is formed by subsequent deposition of abundant materials of different origin. This thickening occurs at the same time as the filling of the stylar canal. Both events are paralleled by considerable dictyosomic activity, the formation of a large amount of rough endoplasmic reticulum, and the incorporation of small cytoplasmic masses into the cell wall, due to plasmalemma evaginations. — The material in the stylar canal has a heterogeneous ultrastructure aspect and consists of polysaccharides, proteins and lipids; it presumably provides nutrients for the growing pollen tubes.
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    Resistenzphysiologische Grundlagen der evolutiven Kälteakklimatisation von Sproßpflanzen (1981)
    Springer
    Plant systematics and evolution 137 (1981), S. 145-180 
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    ISSN: 1615-6110
    Keywords: Coniferophytina ; Angiosperms ; Arecaceae ; Poaceae ; Quercus ; Citrus ; sclerophyllous trees ; mountain plants ; Acclimatation ; chilling resistance ; frost resistance ; stress ecotypes
    Source: Springer Online Journal Archives 1860-2000
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    Notes: Abstract Gradations in cold resistance of plants with different latitudinal and altitudinal distribution, and the various categories of chilling and freezing resistance are hypothesized to be evolutionary steps of adaptive responses to increasing low temperature stress and annual seasonality. The gradual lowering of the critical phase transition temperature of biomembrane lipids, the capacity of persistent supercooling of tissues, and the development of a dormancy linked freezing-tolerance are considered to be essential mechanisms resulting in improved acclimatation to low temperature climates.
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    Differentiation of Fraction 1 protein in relation to age and distribution of Angiosperm groups (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 89-113 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Nicotiana ; Gossypium ; Lemnaceae ; Fraction 1 protein ; differentiation and age of taxa ; migration to Australia ; land connections ; long distance dispersal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Fraction 1 protein (F-1-protein) (ribulose bisphosphate carboxy-lase-oxygenase) contained inLemnaceae has been evolving for at least 50 million years because fossils of these plants have been identified in strata belonging to the Upper Cretaceous. Electrofocusing F-1-protein resolves the large subunit polypeptides coded by extranuclear DNA and the small subunit polypeptides coded by nuclear DNA. Four differences affecting isoelectric points of the large subunit polypeptides and eight affecting the small subunit polypeptides are now present among eleven species representing the four genera comprising theLemnaceae. In comparison, four differences in the large and 13 in the small subunit polypeptides exist among 63 species ofNicotiana; four differences in the large and eight differences in the small subunit polypeptides exist among 19 species ofGossypium. The number of differences in F-1-protein composition being of the same order of magnitude for the generaNicotiana, Gossypium, and the familyLemnaceae, we infer that these Angiosperms are of similar antiquity. Nicotiana species indigenous to Australia and Africa contain F-1-proteins whose large subunit polypeptides are different but some of whose small subunit polypeptides are like those found in species from the Western Hemisphere. The same situation is found for the F-1-protein inGossypium. These results are in harmony with the view that species ofNicotiana andGossypium have arrived in Australia via former land connections between S. America, Antarctica, and Australia.
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    The tubular exine ofLauraceae andHernandiaceae, a novel type of exine structure in seed plants (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 139-146 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Magnoliidae ; Lauraceae ; Hernandiaceae ; Pollen morphology ; pollen ultrastructure ; Angiosperm phylogeny
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    Topics: Biology
    Notes: Abstract The pollen grains ofLauraceae andHernandiaceae are characteristic in having a tubular exine of ± microfibrillar structure. This is coated with a layer of medium electron-dense globules and very peculiar spines, made up of a substance differing from that of the exine. Such a pollen wall structure is otherwise unknown in seed plants and thus adds to the list of odd features erratically present in various taxa of the Ranalean complex.
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    Effect of allopolyploidy on the activity of selected enzymes inHibiscus (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 189-198 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Malvaceae ; Hibiscus acetosella ; H. asper ; H. surattensis ; H. radiatus ; andH. cannabinus ; Allopolyploidy ; evolution of dosage compensation ; alcohol dehydrogenase ; malate dehydrogenase ; leucine aminopeptidase
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    Notes: Abstract Mature seeds of diploid and tetraploidHibiscus species were analyzed for enzyme activity (alcohol dehydrogenase, malate dehydrogenase, leucine aminopeptidase), total protein content, DNA amount and dry weight. The recently formed tetraploid,H. radiatus, generally had enzyme and protein levels very similar to the sum of its progenitors, while the more ancient speciesH. acetosella had several lower levels. This difference may reflect the greater amount of timeH. acetosella has had to evolve dosage compensations.
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    Genetic determination of pappus part number in the annual hybridMicroseris B 87 (Asteraceae—Lactuceae) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 235-246 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Asteraceae ; Lactuceae ; Microseris ; Canalized numbers ; quantitative genetics ; evolutionary genetics ; pappus parts
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    Topics: Biology
    Notes: Abstract The ChileanMicroseris pygmaea has a ten-part paleaceous pappus while the CalifornianM. bigelovii has five pappus parts on each achene. Hybrids between the two species have between five and ten pappus parts with averages below 7.5. Hybrid B 87 has an F 1 average value of 6.7 pappus parts. 140 F 2 plants were raised from this hybrid, and 12 F 3 families were obtained by selfing from F 2 plants. One larger F 4 family has been raised. Pappus part number in all of these is still canalized between 5 and 10. Variation within these limits is genetically determined by a quantitatively acting polygenic system. Modeling of this system suggests that a minimum of four, but probably not many more, genes are involved. This opens the possibility of a complete genetic analysis of the system.
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    Seed and fruit anatomy ofCocculus hirsutus (Menispermaceae) (1981)
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    Plant systematics and evolution 139 (1981), S. 95-102 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Menispermaceae ; Cocculus hirsutus ; Seed ; fruit ; anatomy ; affinities
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The ovules ofCocculus hirsutus are anatropous, bitegmic and, crassinucellate. The fruit is drupaceous, black purple, and laterally compressed and has a pericarp demarcated into exocarp and endocarp. The seeds are curved around the basal bodies. Testa and tegmen cells are thin-walled and unspecialized. In the ripe seed the inner epidermis of the tegmen persists, whereas the entire testa and the outer layer of the tegmen degenerate. Relationships of theMenispermaceae toRanunculaceae, Berberidaceae, andLardizabalaceae are supported.
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    Der Knotenbau einigerRubiaceae (1981)
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    Plant systematics and evolution 139 (1981), S. 103-111 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Rubiaceae ; Nodal anatomy ; leaf base ; stipules
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    Topics: Biology
    Notes: Abstract The leaf base vascularization in most of theRubiaceae corresponds to the unilacunar pattern with one complex trace. Only some species are known to have a trilacunar nodal pattern with three traces. In the unilacunar type one pair of smaller bundles separates from the complex lacunary leaf trace laterally, each soon forking into two arms: One arm becomes a marginal vein of the petiole, the other, besides supplying the stipules, forms a ± distinct vascular “bridge” within the cortex of the nodal flanks. In theRubieae this flank bridge develops as a very distinct vascular “ring” commissure out of which the whorled leaf-like appendages are vascularized; only the opposite true leaves receive their complex trace out of the lacunes directly. Axillary branches originate only from these true leaves.
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    Sclerorhachis leptoclada (Asteraceae-Anthemideae), eine neue Art aus dem südlichen Khorasan (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 297-299 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Asteraceae-Anthemideae ; Sclerorhachis leptoclada Rech. f. ; spec. nova ; Flora of Iran
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    Topics: Biology
    Notes: Abstract A fourth species ofSclerorhachis, S. leptoclada Rech. f., has been discovered in S. Khorasan. It differs from the three known species by its tender habit, rosette leaves with few short segments, extremely reduced stem leaves, and very small heads.Sclerorhachis with its four vicarious species confined to the most arid parts of the Iranian highlands is believed to belong to the paleoxeromorphics (Rechinger 1952).
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    Heterochromatin and chromosome variation in cultivated species ofTulipa subg.Eriostemones (Liliaceae) (1981)
    Springer
    Plant systematics and evolution 139 (1981), S. 47-55 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Tulipa subg.Liliaceae ; Eriostemones ; Giemsa banding ; heterochromatin ; karyosystematics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The chromosomes of several cultivatedTulipa species belonging to the subg.Eriostemones were examined using conventional staining and C-banding techniques. Most of the species have lightly banded chromosomes with heterochromatin content varying from nil to about 15%. The banding patterns of several taxa are described and discussed in regard to species relationships.
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    Zur systematischen Stellung der GattungProckia: Karyologie und Epidermisskulptur im Vergleich zuFlacourtia (Flacourtiaceae),Grewia (Tiliaceae) und verwandten Gattungen (1981)
    Springer
    Plant systematics and evolution 139 (1981), S. 57-76 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Flacourtiaceae:Prockia ; Flacourtia ; Idesia ; Lacistema ; Rawsonia ; Tiliaceae:Grewia ; Luhea ; Karyomorphology ; epidermis ultrastructure ; Chromosomes and systematics of tropical woody plants
    Source: Springer Online Journal Archives 1860-2000
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    Notes: Abstract Detailed analyses of karyology and leaf morphology do not support relationships betweenFlacourtiaceae andTiliaceae. In spite of different chromosome numbers,Prockia (2n = 18),Flacourtia (2n = 22) andRawsonia (2n = 22) are very similar in karyomorphology, indicating a certain karyological uniformity withinFlacourtiaceae. Lacistema (2n = ca. 62) appears more isolated. On the other hand, theTiliaceae Grewia (2n = 18) andLuhea (2n = 36) have much in common and differ remarkably from the Flacourtiaceous genera. The salicoid leaf-teeth ofProckia are also found inIdesia, but never inTiliaceae. Epidermis ultrastructure reveals certain relationships betweenProckia andFlacourtia in contrast to the strongly differingGrewia. Idesia has a rare und unique epidermis sculpture. — Basic chromosome numbers and chromosomal evolution within theFlacourtiaceae are discussed.
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    Chromosome numbers and rust susceptibility as taxonomic criteria inRosaceae (1981)
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    Plant systematics and evolution 137 (1981), S. 23-38 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Rosaceae ; Uredinales ; Chromosome numbers ; rust susceptibility ; tribal classification
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    Topics: Biology
    Notes: Abstract BothNeuradoideae andChrysobalanoideae seem rust-free. TheSpiraeoideae andPomoideae are heavily susceptible toGymnosporangium rusts. While thePrunoideae resemble theRosoideae in being vulnerable to attacks ofPuccinia species, they are additionally susceptible toTranzschelia andThekopsora, whereas theRosoideae are characteristically afflicted byPhragmidium.—It is suggested (a) to treat theChrysobalanoideae as a separate family (Chrysobalanaceae), (b) to transferDryas from theRosoideae-Potentilleae-Dryadinae to theRosoideae-Cercocarpeae, and (c) to divide theRosoideae into two main groups of tribes: (i) the rust-freeKerrieae andCercocarpeae with x = 9, and (ii) the rust-susceptiblePotentilleae, Ulmarieae, Roseae andSanguisorbeae with x = 7.
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    The evolutionary significance of multigermicity in the genusSpinacia (Chenopodiaceae) (1981)
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    Plant systematics and evolution 137 (1981), S. 57-61 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Chenopodiaceae ; Spinacia ; S. turkestanica ; S. tetrandra ; Reproduction ; multigermicity ; seedball ; dioecy ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The presence of multigerm seedballs in the chenopodiacious genusSpinacia is noted. In the wild, colonising, and “weedy” dioecious species,S. turkestanica andS. tetrandra, the distribution of a multigerm seedball could effectively overcome the problem posed by isolation of the sexes. The hypothesis is tested assessing the extent of intra-seedball progeny hybridisations and seed production in the two wild species. The success in seed production by intra-seedball progeny crosses suggests that the distribution of such seedball progeny groups permits not only a percentage survival under isolation of these dioecious plants, but also the colonisation of areas outside that of the parent populations.
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    The embryology ofEpipogium roseum (Orchidaceae) (1981)
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    Plant systematics and evolution 138 (1981), S. 1-7 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Orchidaceae ; Epipogium ; E. roseum ; Microsporogenesis ; female gametophyte ; systematics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Development of pollen and female gametophyte inEpipogium roseum (D. Don)Lindl. has been investigated. The embryo sac conforms to the Apinagia type. The taxonomic position ofEpipogium within the family is discussed.
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    Fruit dimorphism inPhaseolus sublobatus (Fabaceae) and its evolutionary significance (1981)
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    Plant systematics and evolution 137 (1981), S. 67-72 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Leguminosae ; Fabaceae ; Phaseolus sublobatus ; Geocarpy ; amphicarpy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Populations of the annualPhaseolus sublobatus from different ecogeographical zones are genetically differentiated. In twelve populations from the western ghats (Maharashtra range) chasmogamous flowers are arranged in peduncled capitate racemes borne in leaf axils of higher nodes. One population (Poona Race S4) has additional inflorescences, also with chasmogamous flowers, on the main axis between the cotyledonary node and the ground. When the pods of these flowers ripen, the inflorescence gradually coils and, eventually, gets bury the fruits in the soil. This phenomenon is not known in any other plant.—The seed-coat patterns as revealed by SEM, and germination behaviour of both aerial and subterranean seeds are similar, and both types of seeds lack dormancy.—Heavy seed predation selection pressure is probably the principal cause for the evolution of fruit dimorphism inP. sublobatus. The origin of geocarpy in relation to fruit dimorphism and seed predation is discussed.
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    Distributional patterns and an additional species of thePassiflora vitifolia complex: Amazonian species diversity due to edaphically differentiated communities (1981)
    Springer
    Plant systematics and evolution 137 (1981), S. 95-105 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Passifloraceae ; Passiflora involucrata ; stat. et comb. nov. ; Species β-diversity ; Flora of Amazonia ; Peru
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Field studies in Amazonian Peru show that thePassiflora vitifolia complex, a microcosm of many larger taxa, is concentrated in Amazonia with 4 ecologically separated species. One species is restricted to seasonally inundated forests, a second to non-inundated white sand soils, a third to non-inundated lateritic soils, and the fourth mostly to non-inundated alluvial soils. A new combination is formally proposed to recognize the white sand taxon, previously regarded as a variety, as a distinct species:P. involucrata. The importance of β-diversity in maintaining high Amazonian species diversity is emphasized.
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    The flower biology ofCephalanthera longifolia (Orchidaceae)—pollen imitation and facultative floral mimicry (1981)
    Springer
    Plant systematics and evolution 137 (1981), S. 229-240 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Orchidaceae ; Cephalanthera longifolia ; Cistaceae ; Cistus salviifolius ; Hymenoptera ; Halictus ; Flower biology and ecology ; pollination ; pollen imitation ; floral mimicry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Solitary bees (Halictus sp.) were found to be the effective pollinators ofCephalanthera longifolia. In the same foraging flight the bees also visit flowers ofCistus salviifolius which has a similar colour pattern.Cephalanthera offers no reward to its pollinators, but orange papillae on its labellum successfully imitate pollen ofCistus. AsCephalanthera also attracts pollinators in the absence ofCistus, this is regarded as “facultative floral mimicry”.
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    Investigations on the content of steroidal alkaloids and sapogenins withinSolanum sect.Solanum ( = sect.Morella) (Solanaceae) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 61-71 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Solanaceae ; Solanum sect.Solanum ; Diosgenin ; tigogenin ; solasodine ; chemosystematics ; ontogenetic shift
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Plant material of 55 strains from 32 species ofSolanum sect.Solanum ( = sect.Morella) has been investigated for the content of steroidal alkaloids and sapogenins. The leaf-extracts of all species contain diosgenin resp. tigogenin or both together in considerable amount. On the contrary the characteristic steroidal alkaloid solasodine was absent in these samples. For 29 species the presence of steroidal sapogenins has been proved for the first time. In unripe fruits, however, solasodine could be detected in most of the species examined. New occurences of solasodine are reported for seven further species. These chemical results may contribute to a better comprehension of the difficult genusSolanum.—Ontogenetic studies on different organs ofS. atriplicifolium show the relationship between accumulation of steroidal compounds and plant maturity.
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    Tillandsia carminea — eine interessante neue Bromeliacee aus dem Orgelgebirge bei Rio de Janeiro (Brasilien) (1981)
    Springer
    Plant systematics and evolution 138 (1981), S. 293-295 
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    ISSN: 1615-6110
    Keywords: Angiosperms ; Bromeliaceae ; Tillandsia subgen.Anoplophytum ; T. carminea ; spec. nova ; Flora of Brazil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Tillandsia carminea is a new, morphologically and ecologically distinct species, related toT. stricta Solander, which occurs in the Serra dos Orgaos near Teresopolis, Brazil. It has been taken forT. rosea Lindley, but new investigations have shown thatT. rosea is a synonym toT. stricta and thatT. carminea is a good and distinct species.
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    Glycogen accumulation in the parathyroid gland of the rat after fluoride ingestion (1981)
    Springer
    Cell & tissue research 220 (1981), S. 125-130 
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    ISSN: 1432-0878
    Keywords: Glycogen ; Parathyroid gland ; Fluoride ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The parathyroid glands of young male rats given 150 ppm fluoride in their drinking water for 10 weeks were examined by transmission electron microscopy. As a result of fluoride ingestion, the parathyroid chief cells of the experimental animals accumulated glycogen in excess of that seen in control animals given distilled drinking water for the same time period. In the majority of active chief cells, glycogen granules were diffusely spread throughout the cytoplasm as single granules or in small deposits. Large aggregations of glycogen granules were also seen within intercellular spaces. Accompanying the increase in glycogen was a rise in the number and development of the organelles associated with protein synthesis and secretion. The accumulation of glycogen is similar to that in hyperparathyroidism caused by chronic stimulation and prolonged secretory activity of the parathyroid gland. The results of this study suggest that increased amounts of glycogen occur in hyperactive chief cells of the parathyroid in response to the ingestion of large doses of fluoride.
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    Morphometric analysis of the autophagic and crinophagic lysosomal systems in mammotropes throughout the estrous cycle of the rat (1981)
    Springer
    Cell & tissue research 220 (1981), S. 131-137 
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    ISSN: 1432-0878
    Keywords: Rat ; Adenohypophysis ; Mammotropes ; Autophagic and crinophagic lysosomes ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The crinophagic and autophagic lysosomal systems were studied in mammotropes (prolactin secreting cells) of the adenohypophysis throughout the estrous cycle of the rat. By means of morphometric analysis, it was found that the volume of secondary autophagic lysosomes was usually greater than that of the crinophagic type. Although the volumes of both secondary autophagic and crinophagic lysosomes were minimal throughout proestrus and diestrus 2, the autophagic lysosomal volume per mammotrope was elevated during the estrous period. The volume of secondary crinophagic lysosomes per mammotrope increased during late estrus and remained elevated throughout early diestrus 1. Furthermore, there was an inverse relationship between the volume of mature secretory granules per cell and of the crinophagic system. These data suggest a role for lysosomes in the regulation of synthesis and secretion of prolactin by the adenohypophysis of the rat.
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    Cytochemical analysis of intracellular calcium distribution in the anterior pituitary of the rat (1981)
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    Cell & tissue research 220 (1981), S. 191-200 
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    ISSN: 1432-0878
    Keywords: Rat ; Pituitary ; Calcium ; Pyroantimonate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In an attempt to assign morphologic identities to previously distinguished functional calcium compartments in the anterior pituitary of the rat, we employed the potassium pyroantimonate technique for cation localization. Tissues were incubated for In at 37°C in control medium; with 10mM theophylline; or with depolarizing amounts of potassium. Precipitate was quantified on photomicrographs of tissue prepared for electron microscopy with a Talos Systems Digitizer. The nature of the electron dense precipitate was dependent on the experimental state of the tissue. Treatment with 5 mM EGTA abolished the dense precipitate. Electron microprobe analysis also confirmed that calcium was the predominant cation in the observed precipitate. The most significant changes in precipitate deposition occurred along the plasma membrane, the limiting membrane of secretory granules and within mitochondria. Dense precipitate was present along the plasma membrane only in cells treated with potassium. Control tissue exhibited higher levels of precipitate associated with the limiting membrane of secretory granules than either theophylline-treated or potassium-treated tissue. Mitochondria contained more precipitate in potassium-treated tissue than in controls; the mitochondria of theophylline-treated tissue contained intermediate levels of precipitate. Addition of either theophylline or depolarizing amounts of potassium has been associated with hormone secretion in anterior pituitary tissue of normal rats. Kinetic studies in our laboratory indicate that intracellular calcium shifts occur. The pyroantimonate technique is useful in verifying morphologically the calcium compartments involved in shifts in intracellular calcium.
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    The relationship between the nuage and the chromatoid body during spermatogenesis in the Rat (1981)
    Springer
    Cell & tissue research 215 (1981), S. 425-430 
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    ISSN: 1432-0878
    Keywords: Nuage ; Chromatoid body ; Spermatogenesis ; Germ cell determination ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytoplasmic structures ultrastructurally similar to the nuage are present in the cytoplasm of all spermatogenic cells in adult rats. The nuage is a discrete organelle which should not be confused with the chromatoid body. In step 7–8 spermatids transient contact is established between the nuage and the chromatoid body. This indicates a very specific recognition of the nuage by the chromatoid body. It is suggested that the nuage and the chromatoid body are separate cell organelles the functions of which are somehow related to each other.
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    URL: http://dx.doi.org/10.1007/BF00239125
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    Effects of pimozide on the ultrastructure of the pars intermedia in the rat (1981)
    Springer
    Cell & tissue research 217 (1981), S. 397-403 
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    ISSN: 1432-0878
    Keywords: Pituitary gland ; Rat ; MSH-cells ; Pimozide ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of pimozide, a dopamine receptor-blocking agent, were studied in the pars intermedia of the rat. The animals received 100 μg/100 g pimozide daily for 2, 5, 10, 15, and 20 days. Pimozide induces ultrastructural changes after 5 days of treatment. About 50% of the MSH-cells display characteristics of stimulation. Their cytoplasm is partially or totally depleted of secretory granules. The rough endoplasmic reticulum displays a network of interconnecting cisternae and ribbon-like structures. The well-developed Golgi complexes exhibit numerous dilatations of their cisternae, which contain electron-dense material. The nerve endings are not altered. Twenty days after treatment, the above-described changes have not decreased in magnitude. The present findings suggest that pimozide stimulates the mechanism of synthesis and release in some MSH-cells, most probably the elements underlying an inhibitory dopaminergic control.
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    Somatostatin-immunoreactive fiber projections into the brain stem and the spinal cord of the rat (1981)
    Springer
    Cell & tissue research 217 (1981), S. 531-552 
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    ISSN: 1432-0878
    Keywords: Somatostatin fiber projections ; Brain stem ; Spinal cord ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary By use of the PAP-immunohistochemical staining technique with serial sections, somatostatin-immunoreactive fiber projections into the brain stem and the spinal cord are described. These projections originate in the periventricular somatostatin-immunoreactive perikarya of the hypothalamus and form three main pathways: (1) along the stria medullaris thalami and the fasciculus retroflexus into the interpeduncular nucleus; (2) along the medial forebrain bundle into the mammillary body; and (3) via the periventricular gray and the bundle of Schütz into the midbrain tegmentum. Densely arranged immunoreactive fibers and/or basket-like fiber terminals are observed within the following afferent systems: somatic afferent systems (nucleus spinalis nervi trigemini, substantia gelatinosa dorsalis of the entire spinal cord), and visceral afferent systems (nucleus solitarius, regio intermediolateralis and substantia gelatinosa of the sacral spinal cord). These projections form terminals around the perikarya of the second afferent neuron. Perikarya of the third afferent neuron are influenced by somatostatin-immunoreactive projections into the auditory system (nucleus dorsalis lemnisci lateralis, nucleus corporis trapezoidei). Furthermore, a somatostatin-immunoreactive fiber projection is found in the ventral part of the medial accessory olivary nucleus, in nuclei of the limbic system (nucleus habenularis medialis, nuclei supramamillaris and mamillaris lateralis) and in the formatio reticularis (nucleus Darkschewitsch, nuclei tegmenti lateralis and centralis, nucleus parabrachialis lateralis, as well as individual perikarya of the reticular formation). Targets of these projections are interneurons within interlocking neuronal chains.
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    Synaptic input to the axon hillock and initial segment of inhibitory interneurons in the cerebellar cortex of the rat (1981)
    Springer
    Cell & tissue research 217 (1981), S. 553-562 
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    ISSN: 1432-0878
    Keywords: Axon hillock ; Interneurons ; Cerebellar cortex ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The axon hillock (AH) and initial segment (IS) of 10 Golgi neurons and 6 basket cells in the cerebellar cortex of the rat were investigated by electron microscopy using serial sections. An average of 10.4 and 11.3 synaptic terminals were observed to establish synaptic contact with the axon hillock region of Golgi and basket cells, respectively. Most of these terminals were identified as the varicosities of the ascending parallel fibers. It is suggested that the focal innervation of AH regions represents an excitatory input pattern which is basically different from the randomly distributed, huge, parallel-fiber input onto the dendritic trees of Golgi and basket cells. In contrast to Golgi and basket neurons, no accumulation of parallel-fiber synapses was observed around the AH of stellate cells. The IS proper of the three neuronal types were devoid of true axo-axonal synapses.
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    Intercellular channels in the pars tuberalis of the rat hypophysis and their relationship to the subarachnoid space (1981)
    Springer
    Cell & tissue research 218 (1981), S. 345-354 
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    ISSN: 1432-0878
    Keywords: Hypophysis ; Pars tuberalis ; Intercellular channels ; Subarachnoid space ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A system of intercellular channels is described in the pars tuberalis (PT) of the female rat. These spaces are lined by all types of cells found in the PT and are not sealed off by tight junctions. Ventrally and dorsally, the intercellular spaces open toward the basement membranes separating the PT from (i) the subarachnoid space, and (ii) the perivascular space of the portal capillaries, respectively. These intercellular channels differ from the follicles, which are also found in the PT, being lined by a particular type of cell. In a second group of female rats an epoxy mixture was injected into the third ventricle; 10 min thereafter horseradish peroxidase was infused into the cisterna magna. After processing the brain for the demonstration of exogenous peroxidase, it was found that the tracer had reached the subarachnoid space adjacent to the hypothalamus and entered into all ventricular cavities with the exception of the infundibular recess. Under these experimental conditions it was found that the tracer fills all intercellular channels of the PT, thus indicating that there is no barrier between the subarachnoid space and the PT. It is suggested that the subarachnoid space should be regarded as a probable route for the transport of trophic factor(s) and/or secretory product(s) of the PT.
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    Cells capable of uptake of horseradish peroxidase in some circumventricular organs of the cat and rat (1981)
    Springer
    Cell & tissue research 219 (1981), S. 85-92 
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    ISSN: 1432-0878
    Keywords: Circumventricular organs ; Reticuloendothelial system ; Phagocytic cells ; Horseradish peroxidase ; Cat ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structure of mesenchymal cells distributed in some of the “hypendymal organs” of the circumventricular system in the cat and rat was demonstrated after intravenous injection of high doses of horseradish peroxidase. These cellular elements were observed in the vicinity of blood vessels of the organon vasculosum laminae terminalis, subfornical organ and area postrema. Electron-microscopically, these cells located between the basal laminae of the brain parenchyma and the blood capillaries show long cellular processes encircling fenestrated capillaries. Light and electron-microscopic examination revealed that this cell type is identical with the “horseradish peroxidase-uptake cells”, previously reported in the vicinity of the hypophysial portal system. Such phagocytic cells may be considered as a cellular component intervening between the brain parenchyma and the blood stream, playing a role in selective barrier functions in the above-mentioned circumventricular organs where a blood-brain barrier in the classical sense of the definition is lacking.
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    A retinal projection to the lateral hypothalamus in the rat (1981)
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    Cell & tissue research 214 (1981), S. 257-269 
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    ISSN: 1432-0878
    Keywords: Retinal projection ; Lateral hypothalamus ; Dendrites in optic tract ; Axodendritic synapses ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This study presents evidence for a retinal projection to neurons in the lateral hypothalamic area (LHA) of the albino rat. In Golgi-Kopsch material dendrites from LHA-neurons are observed to extend through the supraoptic commissures into the optic tract. The presence of dendrites in the optic tract is confirmed by electron microscopy. Numerous axon terminals are observed forming asymmetric synaptic contacts with these dendritic profiles. Following bilateral enucleation, many of the preterminal axons and terminals in synaptic contact with dendrites in the optic tract demonstrate dark degeneration. After intraocular injection of horseradish peroxidase, there is marked labeling of preterminal axons and terminals in the optic tract. These observations indicate that LHA neurons receive a direct retinal projection from terminals making synaptic contact with dendrites of LHA-neurons extending into the optic tract.
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    The temporo-spatial course of degeneration after cutting cortico-cortical connections in adult rats (1981)
    Springer
    Cell & tissue research 214 (1981), S. 303-321 
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    ISSN: 1432-0878
    Keywords: Cortico-cortical connections ; Degeneration ; Time course ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adult albino rats received callosotomies or lesions in the paracingular cortex. Between 12 h and 3 months after injury the structure and topography of the degeneration products were studied by light- and electron-microscopy. The degeneration process was quantified by television-image analysis applied to sections prepared according to a new technique that stains reliably degenerating terminals and lysosomes (Gallyas et al. 1980). All types of cortico-cortical connections show a multiphasic degeneration process: During a precursor stage a small number of dense bodies and mitochondrial granules are stained. These and the few early degenerating axon terminals are much more diffusely distributed than the large number of terminals that degenerate during the following period. The terminal degeneration shows a biphasic time course. One maximum appears at 2–7 days post operation, which corresponds to the well known direct consequence of axotomy. The second peak at 10–20 days post operation could be caused by transneuronal reorganization of the cortical connectivity. Terminal degeneration always begins along the borders between cortical regions and areas, but it may change its laminar and columnar distribution pattern during the second phase. The degeneration products that are phagocytosed by astrocytes seem to be removed by intracellular transport to their perivascular endfeet. The degeneration process ends with fiber degeneration which, especially in laminae I and VI, may form a separate peak after 20 days or more.
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    Circadian alterations in tubular structures on the outer mitochondrial membrane of rat hepatocytes (1981)
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    Cell & tissue research 214 (1981), S. 519-527 
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    ISSN: 1432-0878
    Keywords: Mitochondria ; Tubular structures ; Hepatocytes ; Circadian changes ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Subcellular structures of hepatocytes were examined at 11.00 h and 23.00h (light cycle: 06.00h–18.00h) in four adult male Wistar rats (AF/Han) per time period. 1. The volume density of mitochondria in the cytoplasm of hepatocytes obtained from peripheral parts of liver lobules shows a statistically significant difference between the two time periods examined. 2. Tubular structures arising from the outer mitochondrial membrane are clearly demonstrated. Their cisternae are continuous with the interspaces between outer and inner mitochondrial membranes. 3. These tubular structures often open directly into the cisternae of rough or smooth-surfaced endoplasmic reticulum (rER and sER) and form a “bridge” between the endoplasmic reticulum and mitochondria. 4. At 11.00 h, the rER connected with the tubular structures often possesses very few ribosomes; at 23.00 h, the amount of ribosomes on the rER is substantially greater. Furthermore, at 23.00h ribosomes are also occasionally found on the membranes of the tubular structures. 5. The incidence of tubular structures on the outer membrane of mitochondria varies significantly between the two time periods. 6. The changing pattern of the volume density of mitochondria in the cytoplasm parallels that of the incidence of the tubular structures, i.e., both are high during the active phase and low during the resting phase of the rat. 7. These results suggest that the tubular structures may play an important role in protein transport between the endoplasmic reticulum and mitochondria, and in the rearrangement of rER during a 24-h period.
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    Intraepithelial blood vessels in the vomeronasal neuroepithelium of the rat (1981)
    Springer
    Cell & tissue research 215 (1981), S. 465-473 
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    ISSN: 1432-0878
    Keywords: Vomeronasal organ ; Olfaction ; Intraepithelial blood vessels ; Rat ; Transmission electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Epithelial-vascular relationships are established during the development of the vomeronasal neuroepithelium of the rat. Special attention is given to the fine structure of the endothelial wall of intra-epithelial vessels, to ultrastructural aspects of the neuronal-vascular relationships, and to the appearance of inclusion bodies in the neuronal cells adjacent to these vessels. The neuronal perikarya surrounding the blood vessels are filled with highly developed smooth endoplasmic reticulum. Possible functional implications of the vascularization of the neuroepithelium of the vomeronasal organ in mediating olfacto-endocrine relationships are discussed. It is suggested that the intra-epithelial blood vessels are at least supportive and nutritive in nature, while their implication in an olfacto-endocrine connection remains obscure.
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    The rat pituitary cleft: A correlated study by scanning and transmission electron microscopy (1981)
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    Cell & tissue research 215 (1981), S. 515-529 
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    ISSN: 1432-0878
    Keywords: Pituitary ; Rathke's cleft ; Ultrastructure ; Scanning electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary SEM reveals that the inner surface of the pituitary cleft is lined by a continuous layer of marginal cells possessing microvillous and ciliated apical surfaces. The ciliated cells are more numerous on the posterior side (toward the pars intermedia) than on the anterior side of the cleft (toward the pars distalis). In contrast small infoldings (crypts) were occasionally noted only on the marginal layer covering the distal part of the hypophysis. In some areas of the cleft the surface features of the marginal cells are rather similar to the epithelial cells populating the upper parts of the respiratory tract in their topography and distribution. In other regions they also show striking similarities with the ependymal cells (tanycytes) lining the lateral recesses of the 3rd ventricle and the infundibular process with which the pituitary cleft has a very close topographical relationship. The parenchymal cells of the pars distalis are closely related to the flattened marginal cells of the cleft. The intercellular spaces of the pars distalis form a three-dimensional labyrinthic series of cavities continuous with the submarginal spaces of the cleft. Further SEM and TEM results demonstrate that the majority of the microvillous marginal cells lining both sides of the cleft possess surface features such as bulbous protrusions, laminar evaginations and large cytoplasmatic vacuoles, which are very likely the expression of an active transport of fluids. On the basis of these results it is concluded that the fluid-like material (colloid) present in the pituitary cleft is mainly derived from the fluids contained in the lacunar spaces of the pars distalis. Thus, marginal cells by absorbing fluids from the cleft by active endocytosis, may transport to the pars intermedia material (or hormones) produced in the distal part of the gland and vice versa. The cilia present on many marginal cells, based on their 9+2 tubular pattern, possess a kynetic role. This is very similar to that shown by the ciliated cells of the ependyma lining the brain ventricles. The occurrence of ciliated cells within the pituitary parenchyma (mainly in the follicles) suggests that they probably arise from the ciliated cells populating the marginal layer of the cleft and with which the parenchyma cells are closely related.
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    Ultrastructure of neurons in the ventromedial nucleus or the hypothalamus in ovariectomized rats with or without estrogen treatment (1981)
    Springer
    Cell & tissue research 217 (1981), S. 451-470 
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    ISSN: 1432-0878
    Keywords: Ventromedial nucleus ; Ultrastructure ; Estrogen effects ; Secretory product ; Lordosis ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the ventrolateral and dorsomedial subdivisions of the ventromedial nucleus (VMN) of the hypothalamus was examined in ovariectomized/control and ovariectomized/estrogen-treated rats to compare neurons of these areas to other neurons (specifically the ventrolateral thalamus), and to determine the effects of estrogen on these cells. The neurons of the VMN contain a large nucleus with a prominent nucleolus, rough endoplasmic reticulum (RER), polysomes, a Golgi complex, coated, uncoated and dense-cored vesicles, lysosome-like bodies, inclusion bodies, multivesicular bodies, whorl bodies and myelin figures. Similar organelles were present in the neurons of the ventrolateral thalamus, although polysomes were more prominent, and the cells lacked dense-cored vesicles in the perikarya. Differences in the cells of the VMN between ovariectomized/control and ovariectomized/estrogen-treated rats included a more conspicuous stacking of the RER and greater number of dense-cored vesicles in the estrogen-treated group in both the ventrolateral and dorsomedial subdivisions. In both areas the differences were statistically significant, although more marked in the ventrolateral subdivision. In both VMN subdivisions, the increased stacking of the RER could be correlated with the greater number of dense-cored vesicles and may reflect increased biosynthesis of a secretory product.
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    Ultrastructural observations on rapid formation of neuro-muscular junctions in vitro (1981)
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    Cell & tissue research 217 (1981), S. 647-659 
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    ISSN: 1432-0878
    Keywords: Cell culture ; Neuro-muscular junctions ; Short-term preparations ; Mouse ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of neuro-muscular junctions (mouse, rat) from the time of first contact between neurons and myotubes in culture and the changes which lead to the formation of functional synaptic contacts have been investigated using light microscopy and ultrastructural techniques. An extensive basal lamina was present when the neuronal cell population was added to the developing myotubes in culture. The nerve cells were initially strongly attracted to each other and nerve cell aggregates formed rapidly. It was only when nerve fibres began to grow out of these aggregates to contact developing myotubes that changes within the cytoplasm of the two adjacent cells were observed. These developments included accumulations of filaments, membrane densities, mitochondria and large clear vesicles within both cells in the region of contact. In addition, collections of glycogen granules and an extensive membrane reticular complex were found within myotubes, and an extensive granular material filled many of the nerve processes. The basal lamina within the intercellular space appeared more electron-dense than elsewhere and was traversed by strands linking the two cell membranes. These features all appeared to be stages in the initial formation of neuro-muscular junctions. It was only after these events had occurred that presynaptic vesicles gradually appeared within the future nerve terminal. The results of this paper therefore support the view that synaptic transmission at developing mammalian neuromuscular junctions is not necessarily dependent on the presence of presynaptic vesicles.
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    Morphological studies on neuroglia (1981)
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    Cell & tissue research 218 (1981), S. 75-86 
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    ISSN: 1432-0878
    Keywords: Microglia ; Macrophages ; Chemical lesion ; Kainic acid ; Hippocampus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Light-and electron-microscopic investigations of kainic acid-induced lesions revealed a marked macrophage response and “microgliocytosis”. The hematogenous origin of reactive elements, such as brain macrophages and “microglia-like reactive cells”, was demonstrated when blood phagocytes were labeled with carbon particles or horseradish peroxidase prior to induction of the kainic acid-lesion. The induced lesion showed a proliferation of microglial cells, which led to a state of “microgliocytosis” in the later stage of lesioning. Since it is now generally accepted that microglial cells in the state of “microgliocytosis” are derived from the “microglia-like reactive cells”, proliferated microglial cells in the brain lesions are probably of hematogenous origin. The relationships among the brain macrophages, the “microglia-like reactive cells” and the intrinsic microglial cells are discussed.
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    Elastic fibers associated with collagenous fibrils surrounded by reticular cells in lymph nodes of the rat as revealed by electron microscopy after orcein staining (1981)
    Springer
    Cell & tissue research 220 (1981), S. 445-448 
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    ISSN: 1432-0878
    Keywords: Rat ; Lymph node ; Reticular cell ; Reticular fiber ; Elastic fiber
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopy of the rat lymph node disclosed reticular cells in close association with bundles of collagenous fibrils 30–45 nm in diameter, and electron lucent “amorphous” substances surrounded by microfibrils 11 nm in diameter, with junctional complexes. The amorphous substances, distinctly revealed by orcein staining, and the microfibrils showed morphological characteristics of elastic fibers. Since elastase digestion of 2% glutaraldehyde fixed specimens induced the selective disappearance of the orcein-stainable substances, it was concluded that they are elastin. Elastin often had a close contact with the plasma membrane of reticular cells. It is suggested that reticular cells synthesize elastic fibers.
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    Electron microscopic study of immunoreactive LHRH perikarya with special reference to neuronal regulation (1981)
    Springer
    Cell & tissue research 220 (1981), S. 511-518 
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    ISSN: 1432-0878
    Keywords: LHRH neuron ; Synapse ; Immunohistochemistry ; Electronmicroscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In early postnatal rats, immunoreactive LHRH perikarya in the preoptic area were studied by light and electron microscopy. Synaptic junctions were found between the immunoreactive perikaryon or its process, and the immunonegative nerve fibers. The significance of these synapses is discussed in relation to possible mechanisms by which the activities of LHRH neurons are regulated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216754
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    Autoradiographic localization of 3H-GABA uptake in the thyroid gland of the rat (1981)
    Springer
    Cell & tissue research 220 (1981), S. 873-879 
    Details
    ISSN: 1432-0878
    Keywords: γ-Aminobutyric acid (GABA) ; Autoradiography ; Thyroid gland ; Transport ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The uptake of γ-aminobutyric acid (GABA) in the thyroid gland of the rat was studied autoradiographically following in vitro incubation. High-affinity GABA uptake was localized in follicle cells, whereas C cells (parafollicular cells) in general did not accumulate GABA by high-affinity transport. The follicle cells were also the main sites of low-affinity GABA uptake. Additionally, some nerve fibres were found to accumulate GABA. The predominant localization of GABA uptake in follicle cells is discussed in view of a presumed role of GABA in thyroid function.
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    URL: http://dx.doi.org/10.1007/BF00210468
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    Comparative studies of quinacrine-positive neurones in the myenteric plexus of stomach and intestine of guinea-pig, rabbit and rat (1981)
    Springer
    Cell & tissue research 221 (1981), S. 93-107 
    Details
    ISSN: 1432-0878
    Keywords: Quinacrine ; Myenteric plexus ; Non-adrenergic, non-cholinergic nerves ; Guinea-pig ; Rabbit ; Rat ; ATP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The number of quinacrine-fluorescent nerve cell bodies and the percentage of the ganglion area occupied by this fluorescence within stretch preparations of the myenteric plexus of the stomach and ileum of the guineapig, rabbit and rat were assessed. The number of quinacrine-positive cell bodies per cm2 of plexus varied between 1045 in the rabbit ileum to 2633 in the rat stomach, whilst the percentage of the ganglionic area occupied by fluorescence was approximately 10 %. The distribution of quinacrine-fluorescent nerve fibres and cell bodies in the myenteric plexus was compared to the distribution of nerves revealed by catecholamine fluorescence and by staining for acetylcholinesterase in the stomach and ileum of all three species. Quinacrine fluorescence appears to be selective for non-adrenergic, non-cholinergic nerves; the possibility that it binds to high levels of ATP is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216573
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    The effects of short-term fluoride ingestion on bone formation and resorption in the rat femur (1981)
    Springer
    Cell & tissue research 221 (1981), S. 421-430 
    Details
    ISSN: 1432-0878
    Keywords: Fluoride ; Bone ; Mineralization ; Resorption ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The femurs from rats given 120 ppm fluoride in their drinking water for 4 weeks were examined with histological, histochemical, and radiographic methods. Blood removed from the rats prior to sacrifice was analyzed for calcium, phosphorus, and alkaline phosphatase. Results of this study indicated that the ingestion of fluoride produced wide osteoid seams on the periosteal surface of the femoral diaphysis within 4 weeks. The increase in osteoid appeared to be due to an increase in the number of osteoid-producing cells (osteoblasts) along with a subsequent delay in the mineralization of this tissue. The metabolic activity of osteoblasts did not appear to be affected since the intracellular production of acid and alkaline phosphatase was not inhibited. However, due to the high concentration of fluoride ingested, abnormal collagen deposition and a change in bone mineral may have combined to cause a delay in osteoid mineralization. Mineralization was also delayed in the distal femoral epiphyseal plate resulting in an increase in the number of hypertrophied cells. Resorption of metaphyseal trabecular bone, presumably formed prior to fluoride administration, was increased causing a reduction in the amount of trabeculae extending into the shaft of the femur. Concurrent with these changes in bone, the serum levels of calcium, phosphorus, and alkaline phosphatase remained within normal ranges.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216745
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    Ultrastructure of elastic cartilage in the rat external ear (1981)
    Springer
    Cell & tissue research 218 (1981), S. 149-160 
    Details
    ISSN: 1432-0878
    Keywords: Elastic cartilage ; External ear ; Rat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structure of elastic cartilage in the external ear of the rat was investigated by transmission and scanning electron microscopy. The narrow subperichondrial, boundary zone contains predominantly ovoid cells rich in cell organelles: mitochondria, Golgi complex, granular endoplasmic reticulum and small (40–100 nm) vesicles. Scarce glycogen granules and bundles of 6–7 nm cytoplasmic filaments are also present. Deeper in the boundary zone, one or more cytoplasmic lipid droplets appear and cytofilaments become more abundant. Fully differentiated chondrocytes in the central zone of the cartilage plate resemble white adipose cells. They are globular and contain a single, large cytoplasmic lipid droplet. The cytoplasm is reduced to a thin peripheral rim; it contains a flattened nucleus, few cytoplasmic organelles and abundant, densely packed, cytoplasmic filaments. The intercellular matrix is very sparse. The pericellular ring consists of collagen fibrils about 20 nm in diameter and a proteoglycan cartilage matrix in the form of a “stellate reticulum”. The complex of these two structures appears in the scanning electron micrographs as a network of randomly oriented, ca 100 nm thick fibrils. Spaces between pericellular rings of matrix also contain thick elastic fibers or plates, apparently devoid of microfibrils. In scanning electron micrographs elastic fibers could be detected only in a few areas, in which they were not obscured by other constituents of the matrix. Immature forms of elastic fibers, oxytalan (pre-elastic) and elaunin fibers, were found in the perichondrial and boundary zones.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210101
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    The hypothalamo-hypophysial system of hypophysectomized rats (1981)
    Springer
    Cell & tissue research 218 (1981), S. 607-622 
    Details
    ISSN: 1432-0878
    Keywords: Hypophysectomy ; Median eminence ; Light and electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The median eminence (ME) of hypophysectomized rats was studied by means of light and electron microscopy. Paraldehyde-fuchsin (PAF)-positive material is seen in the external zone (EZ) of the ME 2–5 days after the operation. Its amount gradually increases especially in the caudal part of the ME during the following few days. Some PAF-positive fibers make contact with the subependymally located blood capillaries. In the most caudal region of the recessus infundibuli they penetrate into the third ventricle. PAF-positive material decreases markedly from the ME of rats two months after hypophysectomy and exposure to a 1% salt load. Fibers of types A1, A2 and B containing granules of 120–220 nm, 100–150 nm and 80–100 nm in diameter, respectively, are seen in the EZ of the ME in hypophysectomized rats, although almost exclusively A2- and B-type structures make contact with the primary portal capillaries in intact animals. All types of neurosecretory fibers establish contact with the subependymal nonfenestrated blood capillaries and penetrate the recessus infundibuli. Some neurosecretory terminals of different types make direct contact with the glandular cells of the pars tuberalis or are separated from them by a thin basal lamina. It is assumed that mainly neurosecretory fibers of types A2 and B are permanently connected with the primary portal capillaries in the EZ of the ME in intact mammals, while the overwhelming majority of fibers of A1-type shows ingrowth during the course of postoperative reparation. The possible physiological significance of the described changes is discussed.
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    URL: http://dx.doi.org/10.1007/BF00210119
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    Immunocytochemical investigation of the subcommissural organ in the rat (1981)
    Springer
    Cell & tissue research 218 (1981), S. 659-662 
    Details
    ISSN: 1432-0878
    Keywords: Peptides ; Subcommissural organ ; Secretion ; Immunocytochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The results of a preliminary immunocytochemical investigation on the subcommissural organ (SCO) in rats show that (1) Reissner's fiber (RF) or essential compounds of the RF are produced by the SCO, (2) the immunoreactive material is produced in the epithelial cells of the SCO as well as in the hypendymal cells, and (3) the immunoreactive material of the SCO belongs to a category of endogenous peptides to date not demonstrable immunocytochemically in other brain structures.
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    URL: http://dx.doi.org/10.1007/BF00210122
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    p-Chlorophenylalanine-induced proliferation of the seminal vesicle epithelium (1981)
    Springer
    Cell & tissue research 219 (1981), S. 159-172 
    Details
    ISSN: 1432-0878
    Keywords: Seminal vesicles ; Proliferation ; Autoradiography ; Biochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Intraperitoneal injection of p-chlorophenylalanine (pCPA) methylester (100 mg/kg body weight) results in an activation of the lysosomal system of the secretory cells in the rat seminal vesicle and an elevation of the activities of lysosomal enzymes within 15 min following the injection. Large autophagic vacuoles are formed, sequestering rough endoplasmic reticulum and part of the Golgi apparatus within 2 h. Shortly after the activation of the lysosomal system an elevation of both DNA and protein synthesis is measured biochemically. 6 h subsequent to the injection a wave of mitoses of the secretory cells begins, reaching a maximum 6 h later and then declining within 3 h. About 12 h following the injection a second rise in lysosomal activity begins, declining within 24 h. The entire sequence of lysosomal and proliferative activities is inhibited in antiandrogen-pretreated rats. Deduced from these findings the following hypothesis of growth regulation of the accessory sex glands is advanced: enhanced loss of intracellular material during autophagocytosis diminishes the intracellular concentration of a substance curtailing cell division below its effective threshold resulting in division of the secretory cells. The prerequisites of this mechanism are (i) a sufficient distributive capacity of the stroma for hormones (androgens) and metabolic precursors, and (ii) sufficient capacity of the basal cells for transporting the precursors to the secretory cells. Sloughing of the secretory cells separates them from these auxiliary structures (stroma and basal cells) and enables the basal cells to divide.
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    URL: http://dx.doi.org/10.1007/BF00210025
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    Monosodium glutamate-induced lesions in the rat cingulate cortex (1981)
    Springer
    Cell & tissue research 220 (1981), S. 239-250 
    Details
    ISSN: 1432-0878
    Keywords: Cingulate cortex ; Monosodium glutamate ; Neurotoxic amino acid ; Cell degeneration ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The brains of neonate albino rats were examined with the light and electron microscope following subcutaneous administration of monosodium glutamate (MSG). In addition to lesions in areas known to be vulnerable to glutamate, such as the arcuate nucleus of the hypothalamus, distinct areas of necrotic tissue were detected in the granular portion of the retrosplenial cingulate cortex. The affected cells display the cytological features characteristic of MSG-lesioned brain tissue, including vacuolization of the endoplasmic reticulum and clumping of chromatin. Numerous pyknotic nuclei can be detected as early as 3 h following treatment. The possible causes of the lesion, particularly the role that may be played by astrocytes, are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210506
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    A comparison of neuropeptide immunocytochemistry in fluid-fixed and freeze-dried brains (1981)
    Springer
    Cell & tissue research 220 (1981), S. 223-230 
    Details
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Freeze-dried brain ; Fluid-fixed brain ; LHRH ; Somatostatin ; Neurophysin ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunocytochemical staining of luteinizing hormone-releasing hormone (LHRH), somatostatin, and neurophysin was compared in rat brains fixed with 1) formalin, 2) Bouin's solution, 3) freeze-dried (FD), or 4) freeze-dried + paraformaldehyde vapor perfused (FDV). The distribution of LHRH fibers was similar in all preparations; however, beads of granular reaction product often appeared finer and more numerous in the median eminence of FD- and FDV brains. Positively stained LHRH perikarya were not observed in any of the preparations. In contrast, somatostatin-immunoreactive perikarya were present in the fluid-fixed and FD brains, although few were observed in FDV brains. Somatostatin-immunoreactive fibers were present in all preparations, but appeared most numerous in the median eminence of FD brains. Staining of neurophysin-containing perikarya and fibers was similar in all preparations. These observations suggest that the FD brain can provide a suitable tissue substrate for immunocytochemistry, demonstrating staining comparable to or surpassing that of more conventional preparations. However, staining of antigens in FD brain was not uniformly successful and may depend on stereochemical characteristics of each antigen as well as properties of the primary antisera used in the staining procedure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210504
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