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DH Kang CL Coe DO McCarthy NN Jarjour EA Kelly RR Rodriguez WW Busse 《Canadian Metallurgical Quarterly》1997,17(8):481-487
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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R Nair G Ramakrishnan NN Nair TK Saikia PM Parikh SR Joshi CS Soman M Mukhadan KT Dinshaw SH Advani 《Canadian Metallurgical Quarterly》1998,82(11):2282-2288
BACKGROUND: Combination chemotherapy consisting of methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisolone, and bleomycin (MACOP-B) has been frequently used for the treatment of non-Hodgkin's lymphoma. This randomized study was undertaken to assess the efficacy and toxicity of this regimen when either doxorubicin or epirubicin was used as the anthracycline drug. METHODS: Between April 1989 and December 1993, 211 previously untreated patients with intermediate grade and high grade non-Hodgkin's lymphoma were randomized to receive either doxorubicin (n=106) or epirubicin (n=105) with the MACOP-B regimen. These patients were followed through December 1996. Numerous clinical features predictive of response and survival were analyzed. Cardiac and noncardiac toxicity in the two treatment arms were compared. RESULTS: The median age of the patients was 48 years. Complete remission was experienced by 122 patients (58.3%); 62 patients (58.5%) achieved complete remission in the doxorubicin arm and 60 (58.1%) in the epirubicin arm. Response rates, time to treatment failure, relapse data, and overall survival were comparable between the two arms. Morbidity due to mucositis, vomiting, peripheral neuropathy, and cardiotoxicity were also comparable. The overall mortality was 10%. Mortality due to neutropenic sepsis was considerably higher among patients who received epirubicin (10 patients) than among those who received doxorubicin (5 patients). Cardiac evaluation revealed no difference in toxicity between the two arms. CONCLUSIONS: Epirubicin was as effective as doxorubicin in terms of patients' responses to therapy. There was no difference in cardiotoxicity between the two treatment arms. However, in this study, the mortality due to neutropenic sepsis was significantly higher among patients treated with epirubicin. 相似文献
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Yu. I. Golovin V. M. Vasyukov E. Yu. Isaeva A. V. Kolmakov R. A. Stolyarov K. V. Tikhomirova A. G. Tkachev A. V. Shuklinov 《Russian Metallurgy (Metally)》2011,(4):334-336
A procedure is developed for modification of the near-surface layers of AO-20-1 alloy (AlSn20Cu, GOST Standard 14113–78) by
carbon nanotubes at a depth of 2 μm. Data on the depth distribution of carbon across the near-surface layer are obtained.
Mechanical and tribological tests of the modified layer are performed. It has been found that the hardness of the near-surface
layer increases by 10–60% at a depth up to 1 μm and the friction coefficient decreases by ∼25 %. 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