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T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation.  相似文献   
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In pigs the lymphocytes emigrating from the intestinal wall were collected by cannulating the lymphatics, labeled in vitro using a fluorescent dye and retransfused. The injection of 6.6+/-4.2 x 10(8) cells resulted in a labeling index between 1.5% in intestinal lymph, 0.2% in the spleen and lymph nodes, approximately 0.1% in the intestinal lamina propria and 0.003% in intraepithelial lymphocytes. About 25 % of the injected cells were present in the blood and 1 % was recovered in the lymph. T cells were found in similar proportions in the injected and the recovered cells in the organs (70-80%). The proportion of IgA+ cells among the immigrated cells in the intestinal lamina propria ranged from 5 to 8%, which in absolute numbers was up to 60% of the injected IgA+ cells. T and IgM+ cells did not show a higher accumulation in any organ. These experiments in conventional, unrestrained animals revealed that (1) T cells immigrate into the intestinal lamina propria, (2) preferential migration of IgA+ cells from gut lymph to the intestinal lamina propria is obvious under in vivo conditions and (3) the immigrated IgA+ cells represent a very small population which is difficult to detect when analyzed in relative numbers.  相似文献   
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Flexner's dysentery is often accompanied with intestinal dysbacteriosis. Disbiotic changes in the intestine contribute to specific shigella endotoxins entering blood flow thus prolonging clinical symptoms of the underlying disease. Administration of bacterial biological preparations (bifidumbacterin forte, lactobacterin) relieves specific endotoxemia, reduces the duration of the disease and has an immunomodulating action.  相似文献   
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The authors review the literature on intra-adenomatous pituitary apoplexy with special emphasis on pathophysiology, diagnosis and therapeutic approach. They present five cases, from a series of 86 patients with pituitary tumors, that developed this syndrome. The patients were diagnosed and followed by the Neurosurgery and Endocrinology Services of Hospital Universitario Clementino Fraga Filho, Universidade Federal do Rio de Janeiro. Diagnosis was confirmed by CT-Scan and MRI in all cases, and the treatment of choice was surgical. Conclusions point to the diagnostic difficulties and the urgency of treatment in this clinical setting.  相似文献   
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