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31.
An anticarbamazepine antibody was detected in the serum of a patient with severe carbamazepine-induced serum sickness. We found that the patient's T cells and IgG antibody recognized an epitope which appeared in subjects showing an allergic reaction, as well as that in subjects who showed no allergic reaction, after long-term carbamazepine therapy. These results show that an anti-carbamazepine immune response does not occur in the majority of subjects who undergo long-term carbamazepine therapy without developing allergic symptoms, although the immunodominant haptenic epitope of carbamazepine is present in their sera.  相似文献   
32.
胃动素对血管灌流大鼠离体胃运动的作用   总被引:8,自引:1,他引:8  
通过血管灌流大鼠离体胃,探讨胃动素对胃运动的影响。结果表明:(1)胃动素可以明显地兴奋胃窦自发的胃运动;(2)胃动素抗血清可以完全消除胃动素兴奋胃窦运动的作用;(3)阿托品可以阻断胃动素兴奋胃窦运动的作用。上述结果提示,胃动素可特异性兴奋血管灌流大鼠胃窦收缩运动,该作用通过壁内胆碱能神经介导。  相似文献   
33.
Human isolates of the highly prevalent TT virus (TTV) have been classified into five major genomic groups (1-5). The geographical distribution of the groups throughout the world is not well known. Five different PCR assays were developed in an attempt to amplify specifically TTV DNAs of each genomic group. Serum samples collected from 72 Brazilian adults (24 voluntary blood donors, 24 hepatitis B virus (HBV) carriers, and 24 human immunodeficiency virus type 1 (HIV-1)-infected patients) were tested. TTV DNA from at least one genomic group was detected in 11 (46%) blood donors, 13 (54%) HBV carriers, and 24 (100%) HIV-1 patients. All five genomic groups were detected in the three populations, with the exception of group 2 in blood donors. Some samples, negative with all five specific assays, were positive with the commonly used untranslated region (UTR) PCR system. On the other hand, TTV DNA was detected in some samples by using specific assays but not with the UTR PCR. Mixed infections with 2-5 TTV isolates from different groups were detected in 21% blood donors, 29% HBV carriers, and 71% HIV-1 patients. Fifteen PCR products (three obtained with each assay) were sequenced. Most sequences showed high (>86%) homology with those of TTV isolates belonging to their presumed groups. However, three sequences had low homology with all TTV sequences available from the DNA databanks. In conclusion, TTV isolates belonging to all five known genomic groups circulate in Brazil, and the results suggest the existence of new and as yet uncharacterised major genomic groups.  相似文献   
34.
Apoptosis is a regulated event crucial to the development and proliferation of normal and malignant B cells. We have studied the role of signals delivered via alpha4 integrin on apoptosis triggered by three different pathways on these cells. For apoptosis induced by serum deprivation, culturing B cells on the recombinant fibronectin fragment H89, a known ligand for alpha4beta1 integrin, resulted in statistically significant (P < 0.005) higher viability values (68%, 65% and 67%) for Ramos, Nalm-6 and EHEB cells, respectively, than culturing cells on poly lysine (42%, 42% and 48%). An antialpha4 MoAb reverted the protecting effect, thus confirming that it was due specifically to alpha4 engagement. Similarly, cells cultured on FN-III4-5, a recently identified fibronectin region which binds activated alpha4 integrin, also showed statistically significant higher viability than poly lysine cultures. Alpha4 engagement however, did not prevent apoptosis induced on Ramos cells via surface IgM. Adhesion of IM-9 cells, a myeloma cell line carrying functional Fas receptors, to the H89 fragment neither increased cell viability upon triggering apoptosis via Fas when compared to poly lysine. These results indicate that alpha4 signalling may overcome B cell apoptosis induced by the lack of growth factors but does not seem to affect the IgM or Fas apoptotic pathways, thus suggesting different intracellular mechanisms for these processes.  相似文献   
35.
The specificity of circulating and kidney-bound IgA during IgA nephropathy is still a matter of discussion. In the present study, high levels of IgA antibodies directed against a panel of self and non-self antigens were found in the serum from patients with IgA nephropathy and were eluted from four out of the seven kidney biopsies studied. After immunoadsorption of pooled selected serum samples on TNP and actin-coated columns, polyspecific IgA antibodies were eluted. This supports the hypothesis that IgA-bearing B cells clones most probably producing polyspecific antibodies are a major feature of human IgA nephropathy. These findings also suggest that it may be hazardous to draw conclusions from the finding of apparently monospecific IgA antibodies in this condition.  相似文献   
36.
The ontogeny of antigen-specific T suppressor cells in thymus and spleen was analyzed in CBA/Ca mice which were rendered tolerant as neonates by subimmunogenic doses of bovine serum albumin (low-zone tolerance). Activity of T suppressor cells from those mice was assessed by an assay in which spleen cells from animals primed with fluorescein-conjugated human gamma globulin can be stimulated in vitro to produce IgG anti-fluorescein antibodies when cultured in the presence of fluorescein-conjugated bovine serum albumin. Carrier-specific T suppressor cells appear first in the thymus (day 10), and much later (day 30) in the spleen. The data are discussed in connection with the possible role of T suppressor cells during induction of tolerance in newborn mice.  相似文献   
37.
Interleukin-6 (IL-6, BSF-2 or IFN-beta 2) is thought to be the major regulator of the acute-phase protein response that follows tissue injury and inflammation, with interleukin-1 (IL-1), tumour necrosis factor and more recently, LIF or HSF III, slightly stimulatory on only certain acute phase proteins. The synthesis of the major acute-phase protein SAA, originally described as being synthesized in response to IL-1, has been claimed recently to be mainly under IL-6 regulation. Our results show that in the human hepatoma cell line HuH-7, IL-1 is the major stimulating cytokine increasing SAA synthesis by a factor in excess of 100-fold. We also show that under most conditions interleukin-6 and tumour necrosis factor stimulate additively in combination with IL-1. Isoelectric focusing has demonstrated that SAA1 and SAA2 alpha are expressed but not SAA2 beta. The HuH-7 cell line is IL-6 responsive since haptoglobin is stimulated mainly by IL-6.  相似文献   
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In patients with coronary heart disease oxidizability of lipids during Cu2+-induced oxidation of blood plasma inversely correlated with fibrinogen content. A positive correlation was found between the amount of lipid peroxidation products in the plasma from these patients and fibrinogen content. The increase in fibrinogen content was associated with high levels of total lipids and triglycerides and low concentration of high-density lipoprotein cholesterol. In vitro experiments demonstrated that fibrinogen reduces oxidizability of blood plasma. Our results suggest that the decrease in lipid oxidizability at high concentration of fibrinogen in patients with coronary heart disease is related to predominant oxidation of fibrinogen and its competition with plasma lipids during Cu2+-induced oxidation.  相似文献   
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