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21.
Localization of corticotropin-releasing activity in the rat hypothalamus   总被引:1,自引:0,他引:1  
Hypothalamic nuclei were removed from frozen sections of rat brain and examined for their corticotropin-releasing activity. The highest concentration was measured in the median eminence. In addition there was significantly more activity detected in the nuclei paraventricularis, supraopticus, suprachiasmaticus and arcuatus than in the other nuclei.  相似文献   
22.
The inflammatory reactions following subcutaneous application of adjuvants revealed characteristic pathological patterns. The injection of complete Freund's adjuvant (CFA) resulted in the formation of large lipid deposits encircled by an inflammatory reaction and concentrically arranged collagen bundles. Bacterial lipopolysaccharide (LPS) caused granulomatous aggregations of mononuclear cells with thrombotic vessel occlusions. Inoculation of the lipopeptide adjuvants induced accumulation of mononuclear cells with only minimal fibrotic changes which were resolved after day 28. Lipopeptide conjugates based on the head group tripalmitoyl-S-glyceryl-cysteinyl-serin (P3CS) can thus be used as effective immunogens and adjuvants without long-term tissue damage.  相似文献   
23.
The course of acute rejection of major histocompatibility complex (MHC)-incompatible isolated rat pancreatic islets transplanted under the kidney capsule was monitored functionally and histologically from day 1 to 10. The patterns observed were compared to those of vascularized whole-pancreas transplants with preserved and suppressed exocrine secretion. In addition the morphologic reactions after isogenic transplantation of islets or whole-pancreas transplants are described. The sequential patterns of acute rejection were found to be essentially identical in isolated islet and whole-pancreas allografts. This was also true for the process of I-A-like class II MHC antigen induction. Endocrine cell necrosis and reduced insulin content of beta cells were detected in isolated islets but not in whole-organ isografts. Thus ischemic damage may have occurred to be transplanted islets on days 1 and 2 because connections to the renal vasculature were not demonstrated before day 3. Islet cell loss was, however, functionally compensated by beta cell proliferation beginning on day 4. From the first day after transplantation, an altered spacial distribution of insulin- and glucagon-containing cells was present in islet isografts. This phenomenon was, however, not unique to islets, but also occurred in duct-ligated whole-organ isografts on days 6 to 10.  相似文献   
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The Williams-Beuren syndrome (WBS) is a complex developmental disorder with multisystemic manifestations including supravalvular aortic stenosis (SVAS), a so-called elfin face, a hoarse voice, and a specific cognitive phenotype. Most WBS patients have a >1 Mb deletion on one of their chromosomes 7 in q11 but except for elastin, whose haploinsufficiency causes the cardiovascular malformations, it is unknown which genes in the deletion area contribute to the phenotype. We have investigated a family with a cytogenetically balanced translocation t(7;16)(q11.23;q13) in which affected individuals manifested a broad spectrum of clinical phenotypes ranging from a hoarse voice as the only feature to the full WBS phenotype. Molecular cytogenetic and DNA sequence analyses of the translocation breakpoint showed that the cytogenetic rearrangement disrupts the elastin gene locus within intron 5 in the exact same manner in all translocation carriers. The recently described large inversion of the 7q11.23 region was not present in this family. Our data demonstrate that disruption of the elastin gene by a translocation breakpoint may cause classical WBS, atypical WBS, SVAS, or no recognisable phenotype, and provide a clear example for extensive phenotypic variability associated with a position effect in humans.  相似文献   
26.
Copolymers of 4-chlorophenyl methacrylate and methyl methacrylate were prepared and investigated by 1H and 13C NMR spectroscopy. The copolymer composition, determined by chlorine analysis, 1H and 13C NMR, was found to be close to the initial composition of the monomer mixture. The sequence analysis was carried out by analyzing the methoxy signals of the 1H NMR spectra. Six out of ten tactic and compositional triads could be resolved. It was found that the copolymers are predominantly syndiotactic and the compositional and tactic triad populations are given. The aromatic carbon atoms are sensitive towards compositional and tactic sequence effects, which results in a switch of the order of the tactic signals at different aromatic carbon atoms.  相似文献   
27.
Using human-mouse somatic cell hybrids containing different parts of chromosome 6 and a DNA probe of the oncogene (V-myb) of avian myeloblastosis virus (AMV), we regionally mapped by Southern blot techniques the human cellular myb (cmyb) protooncogene to 6q21qter.  相似文献   
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Zusammenfassung 1. Es wird über die unterschiedliche Resorption von -Carotin, Vitamin A und Vitamin D aus verschiedenen Lösungsmitteln berichtet.2. Auf die Verwendung von Vitamin A-Ölemulsionen und die Steigerung der Resorption durch wäßrige Vitamin A-Lösungen wird hingewiesen.  相似文献   
30.
The authors examined whether patients suffering from functional gastrointestinal symptoms constitute a separate group within the broader concept of the somatoform disorders. The authors compared 103 patients with a severe gastrointestinal syndrome, 220 patients with a somatization syndrome according to DSM-IV, and 250 clinical control subjects with nonsomatoform mental disorders. The gastrointestinal group showed more catastrophizing thinking, complained more about autonomic sensations, felt bodily weaker, was less tolerant towards bodily discomfort, had developed more hypochondriacal fears and behaviors, was more depressed, and was more severely disabled in different areas of psychosocial functioning than the other groups. These differences, however, disappeared when general somatization was controlled for by analysis of covariance. Only a small effect related to dysfunctional cognitions remained specific to the gastrointestinal syndrome. Because these results do not confirm the idea of an independent gastrointestinal syndrome, general mechanisms of somatization seem to play the dominant role.  相似文献   
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