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171.
多重PCR归化法平行检测HBV和HCV的研究   总被引:3,自引:0,他引:3  
目的:建立一种多重PCR归化法并应用于对HBV、HCV平行检测。方法:利用PCR反应5′端允许添加非互补序列的原理,运用内外两对引物,经过2轮扩增,使目的产物均带上共有序列,再以共有序列为引物进行扩增,实现多重扩增。比较和筛选四种核酸提取方法。运用正交优化法,优化并确定最佳扩增条件。对28份血标本进行对比试验,并进行质量评价。结果:归化多重PCR方法对于HBV、HCV病毒合并感染患者的诊断敏感性为83.5%,诊断特异性为70.0%,诊断指数为153.3%,诊断效率为72.2%;对HBsAg阳性患者的HBV DNA的诊断敏感性为78.6%,诊断特异性为80.0%,诊断指数为158.6%,诊断效率为79.2%。对抗-HCV阳性患者的HCV RNA的诊断敏感性为75.0%,诊断特异性为90.0%,诊断指数为165.0%,诊断效率为83.3%。结论:多重PCR归化法在多基因扩增或多种病原体的同时平行检测领域具有较大应用潜力。该方法实用、准确、可靠,对HBV HCV的防治具有实际意义。  相似文献   
172.
肉苁蓉多糖对衰老小鼠脂质过氧化的影响   总被引:12,自引:0,他引:12  
目的:研究肉苁蓉多糖(polysacchridesofcistanchedeserticolaY.C.Ma,PCD)对亚急性衰老小鼠的抗 脂质过氧化作用。方法:使用D 半乳糖造成小鼠亚急性衰老模型,观察PCD对亚急性衰老小鼠血液和肝脏组 织中超氧化物岐酶(SOD)、脂质过氧化物(LPO)的含量的影响。结果:灌服肉苁蓉多糖衰老小鼠的血液和肝脏 组织中SOD明显高于模型组(P<0.05);LPO的含量明显低于模型组(P<0.05)。结论:肉苁蓉多糖具有明显 的抗脂质过氧化功能,防止亚急性衰老小鼠的组织脂质过氧化损伤。  相似文献   
173.
Progressive myoclonic ataxia, also referred to as Ramsay Hunt syndrome, is characterized by a combination of myoclonus and cerebellar ataxia, infrequently accompanied by tonic-clonic seizures. Its differential diagnosis overlaps with progressive myoclonic epilepsy, a syndrome with myoclonus, tonic-clonic seizures, progressive ataxia and dementia. In patients with progressive myoclonic epilepsy, specific diseases can frequently be recognized, but the diagnostic yield in progressive myoclonic ataxia is much lower. We describe a patient who presented with multifocal myoclonus in his thirties and who later developed cerebellar ataxia and focal dystonia. His father was similarly affected. Genetic studies revealed a mutation in the protein kinase C gamma (PRKCG) gene, known to cause spinocerebellar ataxia type 14 (SCA-14). This case illustrates that both myoclonus and dystonia are part of the clinical spectrum in SCA-14 and that myoclonus can even be the presenting symptom. We suggest that SCA-14 should be considered in the differential diagnosis of progressive myoclonic ataxia.  相似文献   
174.
目的鉴定参与线虫衰老的神经内分泌调控的新基因。方法鉴于神经系统在衰老调控中的重要作用,通过寿命分析和脂褐质自发荧光的检测,从编码突触蛋白的遗传位点中筛选参与衰老调控的基因。我们还进一步检查了这些遗传位点相应的突变体的永久性幼虫形成情况,探讨它们是否可能受胰岛素样信号通路的调控。结果遗传位点 unc-10,syd-2,hlb-1,dlk-1,mkk-4,scd-2,snb-1,ric-4,nrx-1,unc-13,sbt-1,unc-64 可能参与线虫衰老的调控。而且在衰老的调控中,unc-10,syd-2,hlb-1,dlk-1,mkk-4,scd-2,snb-1,ric-4,nrx-1 的功能可能与unc-13,sbt-1,unc-64相反。肠道脂褐质自发荧光的检测进一步证明了筛选出的各基因对应突变体的长寿或短寿表型,是由减慢或缩短的组织衰老所致。在筛选出的基因中,syd-2,hlb-1,mkk-4,scd-2,snb-1,ric-4,unc-64 也参与了永久性幼虫形成的调控。另外,daf-2突变增强了syd-2和hlb-1的表达,降低了mkk-4,nrx-1,ric-4,sbt-1,rpm-1,unc-10,dlk-1,unc-13 的表达。daf-16突变提高了syd-2和 hlb-1 的表达,降低了mkk-4,nrx-1,sbt-1,rpm-1,unc-10,dlk-1,unc-13 的表达. 结论突触功能可能在个体寿命和永久性幼虫形成的调控机制中具有重要的作用。  相似文献   
175.
AIMS: Type 2 diabetes mellitus (DM) and coronary artery disease (CAD) are both associated with endothelial dysfunction and elevated oxidative and inflammatory state. We examined the effect of vitamin C on endothelial function and levels of soluble vascular cell adhesion molecule (sVCAM-1), interleukin-6 (IL-6) and tumour necrosis factor (TNF-alpha), in DM patients with or without CAD and in non-diabetic subjects. METHODS: Thirty-seven patients with DM + CAD, 17 patients with DM without CAD and 21 non-diabetic subjects were divided into groups receiving vitamin C 2 g/day or no anti-oxidant for 4 weeks. Forearm blood flow was determined using venous occlusion gauge-strain plethysmography. Forearm vasodilatory response to reactive hyperemia was considered as index of endothelium-dependent dilation. RESULTS: Baseline levels of IL-6 and TNF-alpha were significantly higher in patients with DM + CAD compared with patients with DM (P < 0.01) or non-diabetic subjects (P < 0.01). IL-6 and TNF-alpha levels were also higher in DM compared with non-diabetic subjects (P < 0.05). sVCAM-1 levels were lower in non-diabetic controls compared with DM + CAD (P < 0.05) or DM (P < 0.05). Reactive hyperaemia was higher in non-diabetic controls compared with DM + CAD (P < 0.001) or DM (P < 0.001). Vitamin C significantly increased reactive hyperaemia only in the DM + CAD group, while it had no effect on serum levels of sVCAM-1, TNF-alpha and IL-6 in any of the groups. CONCLUSIONS: Type 2 diabetes mellitus is associated with impaired endothelial function and increased levels of TNF-alpha, IL-6 and sVCAM-1, especially in patients with DM and CAD. Vitamin C significantly increased forearm vasodilatory response to reactive hyperaemia only in patients with combined DM and CAD.  相似文献   
176.
目的探讨颞叶癫痫的发病机制。方法取健康雄性SD大鼠制成颞叶癫痫模型,用免疫组织化学和原位杂交技术对匹罗卡品致痫后不同时间点CA1区的Sema3C mRNA、Np1 mRNA和蛋白表达进行分析。结果在匹罗卡品致痫后7d,实验组CA1区Sema3C、Np1的表达明显低于对照组(P〈0.01)。结论CA1区Sema3C、Np1的表达下凋可能参与了海马CA1区内的轴突出芽机制。  相似文献   
177.
目的:探讨降纤酶对急性脑梗死(ACI)患者血清超敏C反应蛋白(sCRP)水平的影响及其在改善神经功能缺损方面的作用。方法:46例ACI患者随机分为2组,对照组23例,静脉滴注曲克芦丁注射液,0.6g/d;治疗组23例,入院后立即给予降纤酶10IU溶入250ml生理盐水静脉滴注,1~1.5h滴完,第3、5天各给予降纤酶5IU,其他用药同对照组;应用免疫比浊法检测2组治疗前及治疗后第7天、14天的血清sCRP水平变化,并对神经功能缺损进行评分。结果:2组sCRP水平在治疗后第7天最高,随后逐渐降低。治疗组治疗前血清sCRP水平和治疗前、第7天的神经功能缺损总分与对照组比较差异无统计学意义(P>0.05),治疗组治疗后第7天、14天sCRP水平分别为(7.73±2.16)、(2.92±2.24)mg/L,对照组分别为(10.18±3.16)、(4.66±2.42)mg/L,治疗组明显低于对照组(P<0.05~0.01);第14天治疗组神经功能缺损总分为(10.68±4.08)分,明显低于对照组[(16.81±4.86)分](P<0.01)。结论:降纤酶能明显降低ACI患者血清sCRP水平,有利于减轻炎症反应,改善神经功能缺损程度。  相似文献   
178.
We report a patient with a progressive, predominantly sensory neuropathy and a IgM kappa M-protein that binds to Schmidt-Lantermann incisures. A sural nerve biopsy showed primary axonal damage and IgM deposits at Schmidt-Lantermann incisures were seen by direct immunoperoxidase. Serum from the patient injected into rat sciatic nerve reacts with the incisures as with those in the patient's nerve. The IgM kappa M-protein reacts with chondroitin sulfate C and binds to a broad nerve protein band with a mobility of between 170 and 118 kDa. Peripheral neuropathy may be related to the M-protein, which had immunocytochemical reactivity not previously described for patients with polyneuropathy and IgM monoclonal gammopathy.  相似文献   
179.
To clarify the prevalence of concurrent infection with hepatitis C virus (HCV), hepatitis B virus (HBV) and human T cell leukaemia virus (HTLV), we measured HCV antibody in the population of a district endemic for HBV and HTLV infection. Blood samples were collected in June 1990 from 579 inhabitants of four islands of Uwa Bay in the southwest of Ehime Prefecture in Japan. Anti-HCV antibody against C100-3 protein was detected using an enzyme-linked immunosorbent assay kit (Ortho Diagnostics). Thirteen of the 579 inhabitants (2.2%) were positive for anti-HCV, and this prevalence rate was not significantly different from the frequency of anti-HCV in Tokyo blood donors. A total of 11% (64 of 579) of the subjects were positive for HBsAg and 3.3% (19 of 579) were positive for anti-HTLV. These frequencies of HBsAg and anti-HTLV positivity were distinctly higher than the respective means of Japanese. All anti-HCV positive individuals were negative for HBsAg and anti-HTLV, while 54% (7 of 13) had increased alanine aminotransferase levels. These data suggest that the prevalence of HCV infection is not high even in an area endemic for HBV and HTLV infection.  相似文献   
180.
本文报道用高脂饲料造成家兔高脂血症的研究。经6周后,测定血脂、脂蛋白及血浆假胆硷脂酶等项指标,高脂组各项指标均明显高于对照组,但高脂加维生素E组的各项指标均低于高脂组,结果说明维生素E能降低兔的高脂血症。  相似文献   
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