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91.
目的分别构建人乙型肝炎病毒(HBV)X蛋白、羧基端截断的中分子表面蛋白MHBst78、MHBst155编码基因的真核重组表达载体,以便进一步研究其转录激活功能及对宿主细胞信号传导通路的影响。方法设计合成3对寡核苷酸引物,以adr亚型HBV质粒pHBVDNA为模板,采用PCR法分别扩增HBVX基因、MHBst78与MHBst155编码基因片段;用HindⅢ,KpnⅠ双酶切HBVⅩ基因;用HindⅢ和BamHⅠ双酶切MHBst78与MHBst155编码基因片段后,分别定向插入到真核表达载体pcDNA3.1相应酶切位点,转化宿主菌JM109,提取质粒,分别用上述内切酶酶切及DNA测序鉴定重组质粒。结果酶切重组体显示所切下的片段大小均与预计相符,测序结果与文献报道序列及预计结果一致。结论成功构建了HBVX基因、羧基端截断的HBV中分子表面蛋白MHBst78、MHBst155编码基因的真核重组表达载体,为进一步研究HBV转录激活蛋白HBx、MHBst78MHBst155对宿主细胞信号转导通路的影响奠定基础。  相似文献   
92.
乙型肝炎患者血清中分泌型IgA水平与HBV DNA含量的关系   总被引:1,自引:0,他引:1  
湖北省鹤峰县人民医院检验科,鹤峰 445800目的 研究乙型肝炎患者血清中分泌型IgA(SIgA)水平与乙型肝炎病毒(HBV)DNA含量的关系,为临床提供一个新的评价HBV复制状态及肝细胞损伤的指标。方法 100份经ELISA检测并确诊为乙型肝炎的患者血清用荧光定量PCR检测HBV DNA的拷贝数,用ELISA并经酶标仪定量其SIgA的量。结果 SIgA的含量与HBVDNA的拷贝数的对数呈正相关(r=0.69,P<0.01),在HBsAg( )/HBeAg( )/HBcAb( )组和HBsAg( )/HBeAb( )/HBcAb( )组中SIgA含量差异无显著性意义(P>0.05),而HBV DNA拷贝数前者明显高于后者(P<0.01)。结论 乙型肝炎患者血清SIgA的含量在评价HBV的传染性及肝细胞损伤程度方面比乙型肝炎血清学标志物(HBV-M)更灵敏、准确。  相似文献   
93.
目的 观察免费板式组合药在DOTS中对合并乙肝的涂阳肺结核病人肝损害情况。方法 比较HBsAg、HBeAg、HBcAb阳性的涂阳肺结核病人与无乙肝的涂阳肺结核病人DOTS前后肝功能损害情况。结果 合并乙肝病人肝损害发生率66.3%,无乙肝者肝损害发生率8.6%,两者相比差异有显著性(P〈0.01)。22.5%病人因肝损害需更改治疗方案。结论 DOTS中合并乙肝的病人采用板式组合药用2H3R3Z3E3/4H3R3方案易发生肝损害,对这类病人应慎用常规方案,并要密切全程观察肝功能,尽可能应用肝损害较小的抗结核药。  相似文献   
94.
目的:探讨小儿腮腺炎并发中枢神经系统感染的临床特点.方法:对52例小儿腮腺炎并发中枢神经系统感染的临床资料进行回顾性总结分析.结果:3~7月份为小儿腮腺炎并发中枢神经系统感染的发病高峰季节(92.31%).发病年龄以6~12岁为主(82.69%),多发生于腮腺肿痛3天以上伴有持续发热者(78.85%),少数患者同时有其它脏器的损害,一般治疗疗效较好.结论:腮腺炎极易并发中枢神经系统感染,年长儿发生率高,应推广接种流腮活疫苗降低发病率.  相似文献   
95.
We evaluated twenty renal transplant subjects at various stages of BKV nephritis (BKVN) for BKV-specific IgG and IgM antibodies using ELISA technique and BKV-DNA using PCR. They were divided as early onset (n = 7), stabilizing (n = 3), resolved (n = 8) and late onset (n = 2) BKVN. BKV-specific antibodies and BKV-DNA were simultaneously determined. The mean BKV-specific IgG level in early onset and stabilizing BKVN were 64 and 39 EIA units, and were significantly lower than 138 EIA units seen in resolved BKVN, P = 0.007, P = 0.008. The mean BKV-specific IgM levels in stabilizing BKVN was higher than resolved BKVN (130 vs 51 EIA units), P = 0.006. Mean plasma BKV loads for each group were 955,925, 5642 and 42 copies/mL of plasma, respectively. Prospective study in six BKVN cases revealed mean IgG, IgM levels and BKV-DNA at the time of diagnosis of BKVN as 39, 110 EIA units and 586,758 copies/mL of plasma, respectively. After a mean period of 5.2 months, IgG level increased to 120 EIA units (p = 0.0058) and had no detectable viral copies in circulation. Recovery from BKVN and elimination of BKV is associated with the development of BKV-specific IgG antibodies and this provides insight into the role of humoral immunity to BKV in the pathogenesis of BKVN.  相似文献   
96.
The rising incidence of hepatocellular carcinoma (HCC) in western countries, along with the poor prognosis offered by present-day treatment modalities, makes novel therapies for this disease necessary. Oncolytic herpes simplex viruses (HSV) are replication-competent viruses that are highly effective in the treatment of a wide variety of experimental models of human malignancies. This study seeks to investigate the effectiveness of oncolytic herpes viruses in the treatment of primary HCC cell lines. Sixteen commercially available human HCC cell lines were studied. G207 is an attenuated, replication-competent, oncolytic HSV engineered to selectively replicate within cancer cells. Cell lines were tested for viral sensitivity to G207 and their ability to support viral replication using standard cytotoxicity and viral replication assays. Eleven of 16 cell lines were moderately to highly sensitive to G207 viral oncolysis. HCC cell lines additionally demonstrated the ability to support viral replication in vitro with as high as 800-fold amplification of the administered viral dose observed. G207 is cytotoxic to, and efficiently replicates within, HCC cell lines in vitro. From these data, we suggest that oncolytic HSV therapy may have a role in the treatment of HCC, and in vivo studies are warranted. Presented in part at the 2005 American Hepato-Pancreato-Biliary Association Congress, Hollywood, Florida, April 14–17, 2005. Supported by grants R01CA75461 and R01CA72632 from the National Institutes of Health, and by grant MBC-99366 from the American Cancer Society (Yuman Fong).  相似文献   
97.
本文对1984年1~3月和1985年3~8月共107例急性下呼吸道感染的住院患儿,采用间接免疫荧光法检测其急性期血清抗RSV特异性IgM抗体,并与病毒分离和/或中和试验比较,敏感性为82.1%,特异性为71.8%。RSV感染患儿发病后3天内大多数病例即可从血清中检测出RSV-IgM,因此该法具有早期诊断价值。  相似文献   
98.
Theiler’s murine encephalomyelitis viruses (TMEV) are divided into two subgroups on the basis of their different biological activities. The GDVII strain produces acute polioencephalomyelitis in mice, whereas the DA strain produces demyelination with virus persistence in the spinal cord. A comparative study of GDVII and DA strains suggested that low host immune responses are responsible for the development of acute GDVII infection and that the persistence of infected macrophages plays a crucial role in the development of chronic white matter lesions in DA infection. All 78 mice infected with GDVII died or became moribund by day 13, while none of 54 mice infected with DA died. In the acute stage, the distribution of viral antigens in the central nervous system (CNS) tissue was similar in both GDVII and DA infections, although the virus titer was higher in GDVII infection. In DA infection, a substantial number of T cells were recruited to the CNS on day 6 when they were virtually absent in GDVII infection. The titer of neutralizing antibody was already high on day 6 in DA infection but was negligible in GDVII infection. Development of chronic paralytic disease from day 35 of the DA infection was accompanied by focal accumulation of viral antigen-positive macrophages in the spinal white matter. In addition, white matter lesions comparable to those in chronic DA infection were induced in the spinal cord within 7 days after intracerebral injection of DA-infected murine macrophages. Received: 26 June 1995 / Revised, accepted: 27 December 1995  相似文献   
99.
传染性单核细胞增多症为EB(Epstein-Barr)病毒引起的一种急性或亚急性全身性免疫异常疾病。一次患病后,可获得持久免疫力,多次发病罕见。本文报告了一例传染性单核细胞增多症,9年内3次发病,结合文献资料复习,就本病的诊断、治疗、临床分型、复发问题以及与肿瘤的关系进行了讨论。  相似文献   
100.
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