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Humoral immune reactions to heat shock proteins (hsp) from microorganisms are one aspect of microbial infections in humans. The production of antibodies which are specific to epitopes present on procaryotic hsp leads also to the appearance of cross-reactive serum antibodies in the host organism that react with human hsp. This article discusses the consequences of such autoreactive antibodies for the host in context with the development of immune tolerance and autoimmune diseases, especially rheumatoid arthritis (RA), and in experimental animal models for arthritis such as adjuvant arthritis in rats. On the basis of epitope cross-reactivity between hsp and other host proteins, a hypothesis is presented for the development of autoimmune disease following the production of hsp-specific antibodies.  相似文献   
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It was established that there is little diversity of bryophytes in the derived savanna. Mosses were found in the sampling sites, whereas liverworts were rarely observed. The reproductive methods of four dominant sexually reproducing savanna mosses —Archidium ohioense, Bryum coronatum, Fissidens minutifolius andTrachycarpidium tisserantii were monitored over two consecutive rainy seasons. Protonemal and gametophyte production were noticed in the field in March/April, and capsule dehiscence and spore dispersal occurred in September/October. The sequential stages of development, starting with gametangial production and ending with the falling of the dehisced capsules, occurred within the rainy season. However,A. ohioense andT. tisserantii did not discharge their spores easily (cleistocarpous), unlike the stegocarpous speciesB. coronatum andF. minutifolius. Water availability and possibly high humidity may have contributed to growth. The short period between sex organ formation and dehiscence of capsule seen in these studies, compared with the longer period in some temperate mosses, may be an advantage for bryophytes in a savanna environment.  相似文献   
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大型仪器设备是高校开展教学、科研的物质保证,是高校实验室的主要技术装备,衡量一所高校办学实力和水平的重要指标之一.……  相似文献   
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Summary Hydrochlorothiazide, acutely injected in rats, has a weak analgesic activity per se and potentiates and prolongs the antinociceptive effect of morphine.This work was supported in part by grants from Consiglio Nazionale delle Ricerche, and by Ministero della Pubblica Istruzione, Roma.  相似文献   
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This paper assesses the information content of two survey indicators for consumption developments in the near future for eight European countries in the period 1985–1998. Empirical work on this topic typically focuses on consumer confidence, the perceptions of buyers of consumption goods. This paper examines whether perceptions of sellers of consumption goods, measured by retail trade surveys, may also improve short‐term monitoring of consumption. We find that both consumer confidence and retailer confidence embody valuable information, when analysed in isolation. For France, Italy and Spain we conclude that adding retail confidence does not improve the indicator model once consumer confidence has been included. For the UK the reverse case is obtained. For the remaining four countries we show that combining consumer sentiment and retail trade confidence into a composite indicator leads to optimal results. Our results suggest that incorporating information from retail trade surveys may offer significant benefits for the analysis of short‐term prospects of consumption. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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