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排序方式: 共有411条查询结果,搜索用时 15 毫秒
21.
Saresella M Marventano I Speciale L Ruzzante S Trabattoni D Della Bella S Filippi M Fasano F Cavarretta R Caputo D Clerici M Ferrante P 《Journal of neuroimmunology》2005,166(1-2):173-179
We investigated the apoptosis of myelin basic protein (MBP)-specific T lymphocytes in multiple sclerosis (MS) patients with acute (AMS) or stable (SMS) MS by evaluating the expression of apoptosis markers on peripheral cells. Cells of healthy controls (HC) were evaluated as well. Results showed that mitogen-stimulated apoptosis was comparable among patients and controls, whereas MBP-stimulated CD4+ and CD8+ 7-AAD+ and 7-AAD+ Fas+ cell (apoptotic cells) were significantly reduced in AMS patients. A reduction of the apoptotic rate of myelin-specific CD4+ and CD8+ T lymphocytes could be involved in the immune-mediated destruction of the myelin sheath seen in AMS patients. 相似文献
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Puopolo M Ladogana A Almonti S Daude N Bevivino S Petraroli R Poleggi A Quanguo L Pocchiari M 《Journal of clinical epidemiology》2003,56(5):494-499
The objective was to identify any possible cases of variant Creutzfeldt-Jakob disease (CJD) in Italy, and to estimate the trends in mortality from sporadic CJD for 1993-2000. CJD cases were ascertained through direct notification to the Registry; 382 definite or probable sporadic CJD patients, but no cases of variant CJD were identified. The average yearly mortality rate was 1.04 cases per million inhabitants, with an increase in deaths in the 60-69 and > or =70 year age groups. Survival was shorter in male respect to female and in patients with an age at onset > or =65 years. CJD cases were uneven distributed among different regions in the period 1993-1995, but not herein after. The rise in mortality from sporadic CJD in Italy likely reflects increased awareness and better diagnosis during the years. However, continuous notification and postmortem examination of all suspected cases are recommended for optimal surveillance. 相似文献
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Gibson PR Rosella O Wilson AJ Mariadason JM Rickard K Byron K Barkla DH 《Carcinogenesis》1999,20(4):539-544
Butyrate may have paradoxical effects on epithelial cells of similar origin. This study aimed to examine the hypothesis that one mechanism that dictates a cell's response to butyrate is its state of activation. First, the responses to 24 h exposure to butyrate (1-2 mM) of normal and neoplastic human colonic epithelial cells activated by their isolation and primary culture, and of colon cancer cell lines, LIM1215 and Caco-2, were examined. In primary cultures of normal and cancer cells, butyrate had no effect on alkaline phosphatase activities but significantly suppressed urokinase receptor expression by a mean +/- SEM of 30 +/- 12% and 36 +/- 9%, respectively. Interleukin-8 secretion was suppressed by 44 +/- 7% in normal cells (P < 0.05) but was unchanged in cancer cells. In contrast, the cell lines significantly increased alkaline phosphatase activities by >50%, urokinase receptor expression >2-fold and interleukin-8 secretion >3-fold in response to butyrate. Secondly, the effect of butyrate on Caco-2 cells was examined with or without prior exposure to a specific activating stimulus [tumour necrosis factor alpha (TNF alpha)]. Interleukin-8 secretion increased by 145 +/- 23% and 132 +/- 17% on 24 h exposure to 2 mM butyrate or 0.1 microM TNF alpha alone, respectively. However, in cells pre-treated with TNF alpha, butyrate significantly inhibited secretion by 34 +/- 7% below unstimulated levels. The response to butyrate of urokinase receptor, whose expression was not stimulated by TNF alpha, was unchanged. These effects were mimicked by trichostatin A, an inhibitor of histone deacetylase, suggesting that butyrate's paradoxical effects may have been operating by the same mechanism. In conclusion, some of the paradoxical effects of butyrate do not appear to represent inherent differences between normal and transformed cells. Rather, the response may be determined by the state of activation of the cells. 相似文献
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Genetics of ABO, H, Lewis, X and Related Antigens 总被引:14,自引:0,他引:14
The present knowledge on chemical, enzymatic, serologic and genetic aspects of ABH antigens is reviewed in an effort to produce a simple and coherent genetic model for the biosynthesis of these antigens and chemically related structures. The genetic control of type 1 (Le(a), Le(b), Le(c) and Le(d)), type 2 (X, Y, I, and H), type 3 and type 4 ABH and related antigens in different animal and human tissues is analyzed, taking into account the properties of the glycosyltransferases which are involved in their synthesis and considering possible competition for common acceptor and donor substrates. The phylogeny of ABH determinants shows that they appeared as tissular antigens much earlier than as red cell antigens. The ontogeny of ABH antigens suggests that they behave as differentiation antigens, and an effort is made to correlate their tissular distribution in the adult with the embryological origin of each tissue. 相似文献
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