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21.
HBV、TB合并感染时抗TB治疗对肝功能的影响   总被引:1,自引:0,他引:1  
目的:探讨乙型肝炎病毒(HBV)、结核(TB)杆菌合并感染时抗TB药物所致肝损伤的临床及组织学特点。方法:单纯TB感染者45例,TB合并HBV感染者35例,前4月均服用异烟肼、利福平、吡嗪酰胺、乙胺丁醇,后2月服用异烟肼、利福平。每2~4周复查肝功能、HBV标记物、T细胞亚群等指标,部分患者进行了肝穿刺病理检查。结果:TB HBV组肝功能异常发生率为34.3%,较单纯TB组高,发生时间较单纯TB组早半月,发生平均年龄小8岁;谷丙转氨酶水平、肝组织学炎症积分均较TB组高(P<0.05);肝功能异常者中80%为HBeAb阳性,T细胞免疫功能紊乱较重,CD4 细胞明显减少(P<0.05)。结论:HBV、TB合并感染时,抗TB药物的肝毒性增强,治疗过程中应及时复查肝功能。  相似文献   
22.
Infectious intracavernous carotid artery aneurysms usually present with ophthalmoplegia and/or signs of cavernous sinus thrombosis. We report an unusual case in which a patient with AIDS presented with intractable epistaxis secondary to rupture of a giant infectious intra-cavernous carotid artery aneurysm. Culture of the aneurysm grew mycobacterium avium intracellulare (MAI). The patient was treated successfully by excision of the aneurysm and reconstruction of the internal carotid artery with a saphenous vein interposition graft.  相似文献   
23.
AmpliSensor-聚合酶链反应技术检测结核分支杆菌及临床应用   总被引:14,自引:3,他引:11  
目的探讨Amplisensor-聚合酶链反应(AmpliSensor-PCR)在结核病诊断中的价值。方法采用AmpliSensor-PCR对784例结核病患者及160例肺癌患者的标本进行检测,并与PCR(凝胶电泳后,经溴化乙锭染色)、涂片、培养等法比较。结果AmpliSensor-PCR的敏感性显著高于涂片及培养(P<0.01)。特异性较PCR法高。结论AmpliSensor-PCR可以通过标准曲线划定检出下限,并可换算出标本中原始的靶DNA值,同时具有较高的特异性和敏感性,对肺结核尤其是肺外结核的诊断有一定的临床意义。  相似文献   
24.
脊柱结核是一种常见的肺外结核病。近年来,随着脊柱结核患者逐年增多,不典型脊柱结核患者亦逐渐增多,而不典型脊柱结核诊断较为困难,需要与一般细菌感染、肿瘤以及非结核分枝杆菌感染相鉴别。基因诊断技术是一项诊断脊柱结核的重要工具,对临床不典型脊柱结核的诊断有较高价值。本文将对脊柱结核的流行现状、诊断及基因诊断技术进行综述,以帮助临床工作者对脊柱结核做出更加准确的诊断。  相似文献   
25.
Objective: To evaluate the use of serodiagnosis for tuberculosis and leprosy using mycobacterial antigen 38 kDa, with kits from Omega laboratories, to detect IgG by enzyme immunoassay (EIA).
Method: The study population consisted of 58 patients with evidence of tuberculous infection (culture of Mycobacterium tuberculosis complex or microscopic evidence), of whom 23 had pulmonary and 35 had extrapulmonary disease. There were six subjects who had recently been treated for tuberculosis, 11 patients on treatment for leprosy and 137 patients suspected of having tuberculosis on clinical or radiologic grounds (without laboratory evidence). A control group comprised 35 healthy individuals or patients suffering from diseases other than tuberculosis.
Results: The tests showed that there was a significant difference in antibody levels between the patients with active pulmonary disease, extrapulmonary tuberculosis and leprosy in comparison with the control group ( p <0.001). The sensitivities of the two tests together for proven pulmonary tuberculosis were 100% and 95.7% at 1.0–1.5 and >1.6 EIA cut-off points respectively, while the specificities were 88.5% and 100% at the same cut-off points. The sensitivities for extrapulmonary tuberculosis were 71.4% and only 51.4% at 1.0–1.5 and >1.6 EIA cut-off points. The test was positive in 30 (21.9%) of the 137 suspected patients, while 43 (31.4%) had an equivocal result and the remaining 64 (47.7%) suspects were definitely negative. There was again a significant difference in positivity rates between suspects and the control group.
Conclusions: Omega IgG test is useful in the serodiagnosis of active pulmonary tuberculosis and leprosy, but less sensitive in extrapulmonary disease, particularly in children. Equivocal results may only add to the evidence of tuberculosis in early or minimal disease.  相似文献   
26.
Mycobacterium avium is an opportunistic pathogen that infects individuals suffering from chronic lung disease or immunocompromised patients such as AIDS patients. Here we show that a highly virulent isolate of M. avium proliferated as extensively in T cell deficient as in immunocompetent mice. T cell deficient mice allowed a progressive growth of a less virulent AIDS-derived isolate of M. avium while immunocompetent mice arrested the growth of this isolate. Adoptive transfer of T cell enriched spleen cells between congenic strains of mice differing at the Bcg/Ity/Lsh locus showed that only naturally resistant BALB/c.Bcgr (C.D2) mice infected with the highly virulent strain of M. avium or the naturally susceptible BALB/c mice infected with the lower virulence isolate developed protective T cells and that these cells only mediated protection when transferred to naturally susceptible, but not to naturally resistant, mice. Both strains of M. avium proliferated in bone marrow-derived macrophages cultured in vitro and they were both susceptible to the bacteriostatic effects induced in the macrophages by crude lymphokines produced by concanavalin A-stimulated spleen cells.  相似文献   
27.
Tolerization of pathogenic antigens is one of the experimental strategies that has been proposed to prevent autoimmune disease. We have investigated here whether neonatal intraperitoneal infection of Lewis rats with Mycobacterium bovis-BCG has any effect on the expression of adjuvant arthritis (AA), an autoimmune disease that is produced by immunization of the rats with dead mycobacteria in mineral oil (i.e. Freund's complete adjuvant (FCA)). We found that neonatal infection with 108 viable BCG bacilli rendered all Lewis rats resistant to the expression of AA after FCA immunization. This BCG-induced protection from reactive arthritis was not seen in Lewis rats infected with smaller inocula (106 BCG bacilli) or if the infection was performed after the neonatal period (e.g. at 3 weeks of age). Neonatal administration of 65-kD mycobacterial heat shock protein (hsp65, a key antigen in the etiopathogenesis of AA) failed to protect Lewis rats from AA; injection of lactoferrin (an autoantigen that may be involved in the physiopathology of autoimmune arthritis) to newborn Lewis rats decreased the severity of AA observed after FCA immunization of the animals. Western blotting revealed that Lewis rats that had acquired resistance to AA also showed changes in their repertoire of antibody specificities; among these alterations was decreased anti-hsp65 reactivity. We conclude that neonatal infection with BCG, but not hsp65 injection, renders Lewis rats resistant to AA and that the phenomenon is associated with change in the repertoire of specificities of circulating antibodies.  相似文献   
28.
The relationship between resistance to rifampicin and rifabutin and genetic alterations in the rpoB gene of 41 rifampicin-resistant isolates of Mycobacterium tuberculosis was evaluated. Although 35 isolates with rifampicin MICs > or = 32 mg/L were also rifabutin-resistant, six isolates with rifampicin MICs of 2-16 mg/L were susceptible to rifabutin (MIC < or = 0.5 mg/L). Mutations Asp516Val, Asp516Tyr, Leu533Pro and the double mutation Met515Ile and Leu533Pro influenced susceptibility to rifampicin, but not to rifabutin. All mutations at codons 531 and 526, except one isolate with a His526Cys mutation, correlated with resistance to both compounds.  相似文献   
29.
This study pertains to classification and antigenic analysis of mycobacterial plasma membrane proteins in relation to human T cell proliferative responses, using a ‘fast grower’ Mycobacterium fortuitum as model. Membrane vesicles, prepared by sonication and differential centrifugation, were subjected to biphasic Triton X-1 14 extraction for isolation of integral (detergent phase) and peripheral (aqueous phase) proteins. Neither protein pool showed any appreciable overlap serologically. SDS-PAGE showed five prominent bands in peripheral and three in the integral protein pool, whereas immunoblotting with rabbit antisera identified only two major antigens (60 and 67kD) in the former and five (24, 34, 42, 51 and 54kD) in the latter, ELISA with a panel of anti-mycobacterial MoAbs revealed that nine out of 12 previously known antigens were present in the peripheral protein pool. Only two of them (33 and 40 kD) were additionally detected amongst integral proteins. The membrane-associated immunosuppressive moiety lipoarabinomannan was semiquantitatively located in aqueous phase. In bulk T cell proliferation assays, seven out of 10 subjects belonging to a ‘responder’ background (BT-BB leprosy patients and healthy contacts) showed high responses for Myco. fortuitum antigens. Proliferative response with integral proteins was comparable to that with whole membrane, hut it was significantly higher (P < 0.0005) than t he response with peripheral proteins. The distinction and relevance of integral membrane proteins as a class of mycobacterial antigens make them worthy of consideration in a subunit vaccine design.  相似文献   
30.
 目的 利用显色法芯片技术建立快速鉴定分枝杆菌菌种的方法。 方法 根据美国国家生物技术信息中心(NCBI)提供的分枝杆菌 16S rDNA 基因的保守区和突变区(第 129 ~ 267 位核苷酸的 A 突变区、第 430 ~ 500 位核苷酸的 B 突变区)分别设计引物和寡核苷酸探针,用地高辛标记引物并制备玻璃芯片。采用双重 PCR 技术分别对 16 种分枝杆菌标准株、5 种非分枝杆菌标准株和 120 株分枝杆菌临床分离株(非结核分枝杆菌 40 株、结核分枝杆菌复合群 80 株)进行扩增,扩增产物分别与玻璃芯片进行杂交检测,尼龙膜显色,以显现蓝黑色斑点作为阳性信号,并根据其在芯片方阵中的位置判断分枝杆菌种类。根据芯片杂交结果,选取部分经显色法芯片技术检测的临床分离株进行 DNA 测序。 结果 16 种分枝杆菌标准株和 120 株分枝杆菌临床分离株经 PCR 扩增均各产生 2 条 DNA 片段,其中 1 条长度为 272 ~ 280 bp,1 条长度为 183 ~ 192 bp。16 种分枝杆菌标准株均与芯片上特异性探针杂交,应用显色法芯片技术分析 16 种分枝杆菌标准株和 5 种非分枝杆菌标准株的特异性为 100%。120 株分枝杆菌临床分离株均与分枝杆菌属探针 a 杂交,其中 79 株确定为结核分枝杆菌复合群,38 株确定为非结核分枝杆菌(不产色分枝杆菌 17 株,胞内分枝杆菌 8 株,猿猴分支杆菌 6 株,瘰疬分枝杆菌 5 株,偶然分支杆菌 2 株),另 3 株只与分枝杆菌属探针 a 杂交,没有鉴定到种。选取的 26 株分枝杆菌临床分离株(结核分枝杆菌复合群 8 株,不产色分枝杆菌 5 株,胞内分枝杆菌、猿猴分枝杆菌、未鉴定到种的分枝杆菌各 3 株,瘰疬分枝杆菌、偶然分枝杆菌各 2 株)DNA 测序显示,未鉴定到种的 3 株分枝杆菌中,1 株为结核分枝杆菌突变株,1 株为 Mycobacterium lentiflavum,1 株为 Mycobacterium arupense,芯片上无后 2 种菌株的特异性探针;其余 23 株菌株测序结果与芯片检测结果一致。 结论 显色法芯片技术能简便、快速、灵敏、特异地将大多数分枝杆菌鉴定到种,具有一定的临床推广应用价值。  相似文献   
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