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Zusammenfassung Es wird ein Fall von septischer Purpura nach Lumbaianästhesie mitgeteilt, bei dem das Exanthem scharf in der Höhe der Lumbaianästhesie abschnitt. Mit Hinweis auf manches im Schrifttum Bekannte wird die Frage aufgeworfen, ob sich nicht auch sonst die Vorliebe der Purpura, an den unteren Gliedmaßen aufzutreten, aus Veränderungen im Bereich des Rückenmarks, die ja sehr geringgradig sein können, erklärt.  相似文献   
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Ohne ZusammenfassungMit 1 Textabbildung.  相似文献   
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Aldosterone and 18-hydroxycorticosterone (18-OHB) are produced by the adrenocortical zona glomerulosa. Under normal conditions, plasma 18-OHB levels parallel and are influenced by the same trophic factors that regulate aldosterone production. To evaluate corticosterone-methyl-oxidase II activity, the final step of aldosterone biosynthesis, in conditions associated with chronic derangements of the pituitary-adrenal and/or renal-adrenal axis, we measured the plasma 18-OHB to aldosterone ratio, cortisol, PRA or plasma renin concentration, and potassium (K) in 104 such patients and 15 normal subjects. The 18-OHB to aldosterone ratios in the pituitary-adrenal group were not significantly different from normal regardless of elevated or reduced ACTH and/or cortisol levels [patients with Cushing's syndrome, 3.55 +/- 0.68 (+/-SE); ACTH deficiency, 2.03 +/- 0.34; 21-hydroxylase deficiency, 3.09 +/- 0.23; normal subjects, 2.50 +/- 0.15]. The renal-adrenal group also had normal ratios regardless of plasma renin concentration and K levels [patients with aldosterone-producing adenomas, 2.85 +/- 0.15; idiopathic hyperaldosteronism, 2.14 +/- 0.19; salt-losing nephropathy, 3.06 +/- 0.54; Bartter's syndrome, 2.89 +/- 0.20; isolated (hyporeninemic) hypoaldosteronism, 3.20 +/- 0.39]. Only in patients with 17 alpha-hydroxylase deficiency (230.1 +/- 118.6) was the ratio abnormally high. Chronic perturbations of aldosterone production by ACTH, the renin-angiotensin system, and/or K did not alter this last step of aldosterone biosynthesis (corticosterone-methyloxidase II), as defined by their plasma concentrations. Any influence of these trophic factors must be proximal to the site of 18-OHB production.  相似文献   
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BACKGROUND AND AIMS: Erroneous thymic selection of developing T lymphocytes may be responsible for the expansion of self reactive T cells or may contribute to the absence of regulatory T cells important in controlling peripheral inflammatory processes. Colitis in bone marrow (BM) transplanted Tgepsilon26 mice is induced by abnormally activated T cells developing in an aberrant thymic microenvironment. We investigated the protective role of regulatory CD4+CD25+ T cells in this model. METHODS: BM from (C57BL/6 x CBA/J) F1 mice was transplanted into specific pathogen free Tgepsilon26 mice (BM-->Tgepsilon26). Transplanted mice received no cells (control), sorted CD4+CD25+, or CD4+CD25- cells from mesenteric lymph nodes (MLN) of normal mice. MLN cell subsets were analysed using membrane markers. Cytokine secretion of MLN cells was measured using intracellular cytokine staining and cytokine secretion in anti-CD3 stimulated cell cultures. Colitis was measured by histological scores. RESULTS: CD4+CD25+ cells were reduced in the MLNs of BM-->Tgepsilon26 mice. Transfer of regulatory CD4CD4+CD25+ but not of CD4+CD25- cells reduced the number of MLN CD4+ T cells in BM-->Tgepsilon26 recipients and increased the number of MLN CD8+ cells, thereby normalising the CD4+/CD8+ ratio. CD4+CD25+ but not CD4+CD25- cell transfer into BM-->Tgepsilon26 mice reduced the number of tumour necrosis factor alpha+ CD4+ cells and increased the secretion of transforming growth factor beta by MLN cells. Transfer of 3 x 10(5) CD4+CD25+ cells after BM transplantation into Tgepsilon26 mice prevented colitis whereas CD4+CD25- cells had no protective effect. CONCLUSIONS: These results suggest that defective selection or induction of regulatory T cells in the abnormal thymus is responsible for the development of colitis in BM-->Tgepsilon26 mice. Transfer of CD4+CD25+ cells can control intestinal inflammation in BM-->Tgepsilon26 mice by normalising the number and function of the MLN T cell pool.  相似文献   
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The explosive accumulation of protein sequences in the wake of large-scale sequencing projects is in stark contrast to the much slower experimental determination of protein structures. Improved methods of structure prediction from the gene sequence alone are therefore needed. Here, we report a substantial increase in both the accuracy and quality of secondary-structure predictions, using a neural-network algorithm. The main improvements come from the use of multiple sequence alignments (better overall accuracy), from "balanced training" (better prediction of beta-strands), and from "structure context training" (better prediction of helix and strand lengths). This method, cross-validated on seven different test sets purged of sequence similarity to learning sets, achieves a three-state prediction accuracy of 69.7%, significantly better than previous methods. In addition, the predicted structures have a more realistic distribution of helix and strand segments. The predictions may be suitable for use in practice as a first estimate of the structural type of newly sequenced proteins.  相似文献   
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