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91.
The use of livers from anti-hepatitis B core (HBc) positive donors can alleviate donor shortage. Nineteen of 367 (6%) adults receiving anti-HBc positive allografts [three were hepatitis B antigen (HBsAg) negative, hepatitis B antibody (HBsAb) positive; four were HBsAg positive and 12 were not exposed to hepatitis B viral (HBV) infection] were retrospectively reviewed. In HBsAg negative recipients, immunoprophylaxis (IP) was guided by viral serology and immunohistochemistry (IH) of day 0 and day 7 liver biopsies. If IH was negative, IP was stopped. None of three HBsAg negative, HBsAb positive recipients infected; one (replicating) of four HBsAg positive recipients reinfected and seven of eight (87.5%) HBsAg, HBsAb negative recipients, who did not receive long-term IP, infected after a median time of 2 years (range 1-5); one patient died of liver failure. Four HBsAg, HBsAb negative recipients, receiving life-long IP, remained infection free. Anti-HBc positive donor livers must be directed selectively first to HBsAg positive recipients, next to recipients having HBV antibodies and finally to HBV-naive recipients. Identification of both donor and recipient risk factors for HBV infection before transplantation allows indiscriminate use of antiviral prophylaxis. The necessity for IP therapy should be guided by HBV-DNA testing of donor liver tissue and serum. IH of early liver biopsies is an unreliable marker for predicting antiviral treatment requirements.  相似文献   
92.
凯时治疗慢性重型肝炎患者疗效观察   总被引:2,自引:0,他引:2  
目的探讨凯时即前列地尔脂微球载体制剂(Lipo-PGE1)治疗慢性重型肝炎的疗效。方法将84例慢性重型肝炎患者随机分成两组,对照组予综合治疗及对症治疗,治疗组在该基础上加用凯时10μg溶于5%葡萄糖注射液250ml中静脉缓慢滴注,1次/d,疗程为4周。结果治疗组对慢性重型肝炎的疗效优于对照组(P〈0.01),肝功能改善优于对照组(P〈0.01)。结论Lipo-PCEI是一种治疗慢性重型肝炎安全、有效的药物。  相似文献   
93.
Development of autoimmune hepatitis in primary biliary cirrhosis.   总被引:1,自引:0,他引:1  
AIM/BACKGROUND: Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown aetiology. Up to 10% of patients with typical features of PBC will have additional features of autoimmune hepatitis (AIH). A subset, however, have no such features but go on to develop a 'sequential' AIH overlap syndrome. Objectives: Describe our experience with eight patients who developed AIH after the diagnosis of PBC was made. METHODS: We reviewed the charts of all PBC patients over a 9-year period (from 1996 to 2005). Only PBC patients with no features of AIH were included. RESULTS: There were 1476 patients with PBC. Of these, eight patients developed features of AIH overlap syndrome based on biochemical and histological parameters. Treatment included prednisone and azathioprine for 24 or more months. The majority of patients remained on ursodeoxycholic acid (UDCA) throughout treatment. Response to therapy was defined by improvement in enzymes, and was rapid for all patients. One patient was able to discontinue treatment with prednisone and azathioprine, while seven have continued on therapy to date. CONCLUSIONS: A 'sequential' overlap syndrome of AIH with PBC can occur. Treatment with prednisone and azathioprine may lead to a rapid improvement in aminotransferase levels.  相似文献   
94.
Many cellular signaling pathways are involved in the development of cancer. Depending on the tumor entity, the nature as well as the mode of activation can differ. Some signaling pathways frequently show changes as all tumor cells have to fulfill some basic requirements such as independence from growth factors or insensitivity against apoptosis. In this review, the possibilities of a tumor to manipulate signaling pathways to reach these goals are exemplified based on an archetypical melanoma cell. In addition, new therapeutic options based on the knowledge of signaling pathways will be discussed.  相似文献   
95.
目的采用LuxS缺失突变株模型对B型链球菌中数量感应相关分子LuxS的功能及与其相关的自诱导因子-2数量感应通路进行研究,以探索其毒力调控机制。方法采用RT-PCR法、菌落印迹分析、生长曲线测定、cAMP因子测定等方法对该缺失突变菌株的表型特性进行了研究。最后应用哈氏弧菌作为报告菌株,通过生物发光测定法分析了突变株对B型链球菌诱导报告菌株中的生物发光活性的影响。结果发现此缺失突变可导致B型链球菌中scpB基因表达的上调;与野生株相比,突变株的生物发光诱导活性比野生株降低了大约两倍。结论本研究结果证实了LuxS在GBS中AI-2数量感应通路中的重要性,并为GBS中毒力调控机制的进一步研究提供了新的线索。  相似文献   
96.
目的 研究乙型肝炎病毒(HBV)自身增强子I(enhancerI,ENHI)对HBV DNA疫苗免疫应答的影响。方法 采用PCR法以HBVadr亚型全基因DNA序列为模板分别扩增表面抗原(HBsAg)和HBsA-ENHI基因片段,重组到载体VR1012中,构建两种HBV DNA疫苗,转染CADS-7细胞及HepG2细胞并免疫BALB/c小鼠。采用蛋白印迹、ELISA、ELISPOT等方法检测其在COS-7和HepG2细胞内的表达及小鼠的体液及细胞免疫应答效果。结果 转染的HepG2和COS-7细胞均表达HBsAg;连接ENHI的HBV DNA疫苗转染HepG2细胞后HBsAg表达量明显升高,两种疫苗转染COS-7细胞表达HBsAg无明显差异;免疫小鼠后第2周产生HBsAb及HBsAg特异性细胞毒T淋巴细胞(CTL),两种疫苗免疫产生的HBsAb及HBsAg特异性CTL无明显差异。结论ENHI可使HBV DNA疫苗转染HepG2细胞表达HBsAg明显增加,对转染COS-7细胞表达HBsAg及接种BALB/C小鼠引起的免疫应答无明显影响。  相似文献   
97.
Background Leber’s hereditary optic neuropathy (LHON) is a maternally inherited optic neuropathy caused by mutations in mitochondrial DNA (mtDNA). It is also believed that several epigenetic factors have an influence on the development of LHON.Methods A case series was observed.Results Three patients who developed bilateral optic neuropathy are presented. All patients had a primary LHON mutation in their mtDNA, but also a subnormal vitamin B12 serum level at the time of presentation.Conclusions The clinical picture of optic neuropathy associated with vitamin B12 deficiency shows similarity to that of LHON. Both involve the nerve fibres of the papillomacular bundle. The present case reports suggest that optic neuropathy in patients carrying a primary LHON mtDNA mutation may be precipitated by vitamin B12 deficiency. Therefore, known carriers should take care to have an adequate dietary intake of vitamin B12 and malabsorption syndromes like those occurring in familial pernicious anaemia or after gastric surgery should be excluded.  相似文献   
98.
[目的]探讨各型肝炎的感染率。[方法]研究对象为我院住院及门诊患者,共计4110例。采用微粒子酶免分析法(MEIA)及酶联免疫吸附法(ELISA)进行肝炎分型(甲、乙、丙、丁、戊、庚肝)检测。[结果]4110例受检者中,单纯乙肝感染者133例,占3.24%;单纯丙肝感染者134例,占3.26%;单纯戊肝感染者2例,占0.05%;乙肝合并丙肝感染者3例,占0.07%;丙肝合并戊肝感染者1例,占0.02%;HAV、HDV、HGV无一例感染,感染率为0。另外,男性受检者2088人,乙肝感染者88人,占4.21%;丙肝感染者48人,占2.30%;女性受检者2022人,乙肝感染45人,占2.23%;丙肝感染86人,占4.25%。[结论]除丙肝外,各型感染率均低于全国平均感染率,与相关资料报道相差甚远。乙肝及丙肝仍以单纯感染多见。另,本组资料还显示,男性较女性更易感染乙肝病毒,而女性感染丙肝者远远高于男性,对于丙肝感染的性别差异,尚无报道,需进一步探讨。  相似文献   
99.
目的 观察巯基化合物对内毒素诱导大鼠枯否细胞(KC)NF-kB活性和肿瘤坏死因子-a(TNF-a)释放的影响。方法采用胶原酶灌注和percoll密度梯度离心法分离得到高纯度大鼠KC,在过夜培养后冲洗两遍(不含血清),加入内毒素(LPS)10ng/ml刺激原代培养的KC,观察不同浓度谷胱甘肽乙基酯(GSHEE)及N-乙酰半胱氨酸(NAC)对大鼠KCTNF-a释放和KC内谷胱甘肽(GSH)及NF-kB活性的影响。并观察使用谷胱甘肽合成抑制剂BSO后,对NAC抑制炎症因子的影响,采用凝胶滞留电泳法测NF-kB活性,采用高效液相色谱分析法测GSH水平。结果 LPS诱导KC中GSH水平无变化;GSHEE和NAC可提高KC中GSH水平(P〈0.05),降低NF-kB活性和TNF-a释放(P〈0.05)。NAC与BSO合用时KC中GSH水平无变化,TNF-a释放降低(P〈0.05)。结论 NAC通过抑制KC中NF-kB的激活和TNF-a的释放调节KC功能,但这种抑制作用并非通过增加GSH介导。  相似文献   
100.
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.  相似文献   
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