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61.
Chronic allograft nephropathy (CAN) of renal allografts is still the most important cause of graft loss. A subset of these patients have transplant glomerulopathy (TGP), characterized by glomerular basement membrane (GBM) duplications, but of unknown etiology. Recently, a role for the immune system in the pathogenesis of TGP has been suggested. In 11 of 16 patients with TGP and in 3 of 16 controls with CAN in the absence of TGP we demonstrate circulating antibodies reactive with GBM isolates. The presence of anti-GBM antibodies was associated with the number of rejection episodes prior to diagnosis of TGP. Sera from the TGP patients also reacted with highly purified GBM heparan sulphate proteoglycans (HSPG). Indirect immunofluorescence with patient IgG showed a GBM-like staining pattern and colocalization with the HSPGs perlecan and especially agrin. Using patient IgG, we affinity purified the antigen and identified it as agrin. Reactivity with agrin was found in 7 of 16 (44%) of patients with TGP and in 7 of 11 (64%) patients with anti-GBM reactivity. In conclusion, we have identified a humoral response against the GBM-HSPG agrin in patients with TGP, which may play a role in the pathogenesis of TGP.  相似文献   
62.
Traditionally, the recognition and tolerance of transplanted grafts has been considered to be within the realm of the adaptive immune system. Innate immunity, on the other hand, as the first line of host defense, plays a role in fighting against invading microorganisms. Recently, with the discovery of the Toll-like receptors (TLRs), the role of innate immune responses in the control of adaptive immunity has become a new area of interest. Emerging evidence suggests that in addition to responding to pathogen-associated molecular patterns of microorganisms, TLRs can be activated by endogenous ligands, expressed by mammalian cells. These 'danger signals' may participate in ischemia-reperfusion related organ damage and subsequently influence function and survival of transplanted grafts. Furthermore, it has been suggested that adaptive immune responses can enhance the acute inflammatory responses controlled by innate immunity in organ transplantation. This review addresses the potential involvement of TLRs in different stages of organ transplantation. Intriguing and controversial findings are presented and discussed in order to stimulate more attention to this emerging and potentially important area of research in organ transplantation.  相似文献   
63.
目的:介绍与验证一种反映腰椎间盘突出伴单侧坐骨神经痛的体征——模特征。方法:选取72例经腰椎MRI证实有腰椎间盘突出(L4,532例,L5/S1 40例)并伴单侧坐骨神经痛的患者,男49例,女23例,年龄32~68岁,平均50.7岁。每例患者人院当日由两位医师间隔2h分别检查,患者背对检查者,嘱其取最能缓解坐骨神经痛的站立姿势,若患者出现患侧屈髋屈膝、骨盆倾向患侧的姿势,记为“模特征阳性”,否则记为“模特征阴性”。同时行直腿抬高试验(SLR),阳性患者记录诱发下肢放射痛的最小角度。结果:70例患者两检查者结果完全相同,其中阳性60例,阴性10例,敏感性为85.7%;仅2例患者两检查者结果不一致,重复性97.2%。SLR均为阳性。结论:模特征是诊断伴单侧坐骨神经痛腰椎间盘突出症的简单、敏感的临床体征。  相似文献   
64.
小鼠在45℃高温环境下暴露15min,其网状内皮系统对碳粒的廓清作用明显降低,血清溶血素含量显著下降,绵羊红细胞(SRBC)诱发的迟发型超敏反应明显受到抑制.应激前15min人参根总皂甙(GRS)50、100 mg·kg~(-1),ip,对小鼠的免疫功能有保护作用,可使热应激小鼠网状内皮系统对碳粒的廓清作用免于下降,防止血清溶血素含量的降低,迟发超敏反应不受抑制.  相似文献   
65.
为研究分娩方式是否影响新生儿免疫状态,检测和比较了68例妊娠足月阴道产和64例妊娠足月部宫产分娩的新生儿脐血C3、C4及IgG、IgA、IgM的含量,其结果:IgG的的含量阴产组明显高于剖宫产组,且男婴阴道产组IgG的信明显高于剖宫产。说明剖宫产可参降低新生儿免疫应签及抗感染能力。  相似文献   
66.
粉被虫草提取物对巨噬细胞吞噬功能及CTL活性的影响   总被引:2,自引:0,他引:2  
研究粉被虫草菌丝体提取物在体外对小鼠腹腔巨噬细胞吞噬功能和脾细胞免疫功能的影响,结果表明:粉被虫草提取物在正常情况下不仅能够促进小鼠腹腔巨噬细胞的吞噬功能,而在免疫抑制的情况下,一定浓度的粉被虫草菌丝体提取物还能恢复提高吞噬功能;它不仅能促进正常脾活化T细胞的增殖,而且能恢复环磷酰胺和氢化可的松抑制免疫小鼠脾活化T细胞的增殖;在较高浓度下能增高小鼠脾细胞毒T淋巴细胞(CTL)活性,同时在一定浓度下能恢复免疫抑制小鼠脾CTL活性。  相似文献   
67.
Low numbers of parasites from cloned lines of the rodent malaria parasites, Plasmodium chabaudi chabaudi AS and P. yoelii yoelii A, injected into CBA/Ca mice produce acute but usually self-limiting infections. During crisis, i.e. 1-2 days after peak parasitaemia, 'pre-immune' mice experiencing such 'background' infections were reinfected intravenously with homologous parasites or parasites of heterologous strains or species. P. c. chabaudi AS pre-immune mice controlled an AS challenge with essentially the same kinetics as the background infection. Reinfection of AS pre-immune mice with the heterologous (CB and IP-PCI) P. c. chabaudi strains or P. chabaudi adami DS had little effect on the initial growth of these parasites, although eventually the parasitaemia was controlled. In contrast, a partial inhibitory effect on the growth of P. vinckei lentum DS was evident. Challenge with the non-lethal (A) or lethal (YM) variants of P. y. yoelii resulted in an increase in both the growth and virulence of these parasites. P. y. yoelii A pre-immune mice controlled a homologous challenge, but were less effective at controlling the YM variant. In addition, they were unable to clear rapidly a P. c. chabaudi AS or P. v. lentum DS challenge. Both the multiplication and virulence of P. berghei ANKA were enhanced. These findings demonstrate that resolution of the primary acute parasitaemia in P. c. chabaudi AS- and P. y. yoelii A-infected mice is predominantly mediated by species- and strain-specific mechanisms.  相似文献   
68.
益气补肾汤对小鼠免疫功能的影响   总被引:1,自引:0,他引:1  
目的 :研究益气补肾汤对小鼠免疫功能的影响。方法 :用药理实验的方法 ,将小鼠制成免疫抑制模型 ,灌服益气补肾汤 ,观察和测定小鼠巨噬细胞吞噬功能 ,胸腺、脾指数 ,迟发性超敏反应及溶血素抗体水平。结果 :灌服益气补肾汤的小鼠与灌服蒸馏水的免疫抑制模型小鼠相比 ,巨噬细胞吞噬能力增强 (P <0 .0 5 ) ,胸腺指数升高(P <0 .0 5 ) ,迟发性超敏反应增强 (P <0 .0 5 ) ,且血清溶血素抗体升高 ,脾指数 2组间差异无统计学意义。结论 :益气补肾汤可增强机体免疫功能  相似文献   
69.
Vaccination of mice with attenuated S. japonicum cercariae induces protection against secondary infection which can be transferred to naive mice with serum (VMS). The presence of antibody does not per se impart protection as serum from mice carrying non-attenuated infections (CIS), contains high levels of specific antibody, but confers no protection. Here we describe the increased protection transferred (20 to 68%) with increased number of vaccinations (one to five) given to the donors, and its decline with time after the final vaccination. We also describe the development of IgM, IgA, IgE, total IgG and IgG subclass responses in VMS, giving different levels of protection and CIS, directed against sodium periodate-sensitive and -resistant epitopes in ‘skin-stage’, ‘lung-stage’and ‘liver-stage’schistosomula, adult worms and eggs. In addition, antibody affinity maturation, development of S. japonicum species-specific responses, and vaccination-specific responses were examined. No response developed in parallel with serum-mediated immunity, suggesting immunity may be due to responses against individual antigens. Preliminary examination of antigens recognized in Western blot showed that two schistosomal membrane antigens, of 13 and 40 kDa, were recognized by VMS from mice vaccinated five times (68% protection), but not by twice vaccinated VMS (27% protection). Neither antigen was recognized by non-protective CIS.  相似文献   
70.
中老年人膳食和体液免疫水平的调查   总被引:1,自引:0,他引:1  
黄作能  韦江 《卫生研究》1994,23(4):228-230
作者调查了161例(男:98,女:63)中老年人的营养素摄入量、血浆蛋白及体液免疫水平。结果:该人群的大部分人热能的摄入量达RDA值;膳食蛋白质、维生素A、B2、C、锌和铁的摄入量较低;脂肪摄入量按热能比高于30%者约占30%;血浆总蛋白、球蛋白水平较低,尤其是女性;免疫球蛋白IgA偏低,IgG和IgM偏高。  相似文献   
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