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61.
以浓度为4×10~8TCID_(50)/ml和4×10~5TCID_(50)/ml的病毒液经口感染,4×10~8TCID_(50)/ml和4×10~2TCID_(50)/ml病毒液经胸接种白纹伊蚊(Aedes albopictus)。结果表明1、脑和神经节感染率相同,2、神经系统对病毒敏感性较涎腺高。 相似文献
62.
【目的】研究拉米夫定对HBsAg阳性孕妇的乙肝病毒 (HBV)宫内阻断作用。【方法】拉米夫定组 43例 ,孕 2 8周起口服拉米夫定 ,每天 10 0mg至产后 30d。对照组 5 2例 ,未予用药。两组孕妇均于孕 2 8周、分娩前 ,其新生儿于生后 2 4h内免疫接种前抽静脉血检测HBsAg、HBeAg及HBV的定量。【结果】拉米夫定组孕妇HBV的DNA水平显著下降 (P <0 0 5 ) ,其新生儿宫内感染率 (16 3% )明显低于对照组 (32 7% ) ,P <0 0 5。两组孕妇及其新生儿未发现有不良反应。【结论】携带HBV孕妇产前服用拉米夫定可有效减少HBV宫内感染发生率。 相似文献
63.
乙型肝炎病毒转基因小鼠体内肝靶向反义RNA抗病毒疗效研究 总被引:2,自引:0,他引:2
目的:探讨半乳糖修饰的反义RNA真核表达质粒在乙型肝炎病毒转基因小鼠体内的抗病毒作用。方法:以半乳糖多聚赖氨酸(Gal-PLL)作肝靶向载体,将乙型肝炎病毒基因C区的反义RNA真核表达重组质粒(pCEP4-aC)制备为Gal-PLL-pCEP4-aC。将24只血清HBV DNA、HBsAg阳性的小鼠,随机等分为Gal-PLL-pCEP4-aC治疗组、Gal-PLL-pCEP4对照组和生理盐水阴性对照组,于实验第1天尾静脉分别注射Gal-PLL-pCEP4-aC、Gal-PLL-pCEP4(100μg/只)和等体积的生理盐水,观察治疗前后血清HBV DNA以及HBsAg变化。结果:Gal-PLL-pCEP4-aC治疗组21天时血清HBV-DNA转阴率62.5%(5/8),且7,14,21天时血清HBsAg明显降低;而Gal-PLL-pCEP4组血清HBV DNA转阴1只(1/8),生理盐水组8只均未转阴,两组用药后血清中HBsAg与用药前比较差异性均不明显(P>0.05)。结论:肝靶向反义RNA能在乙肝基因小鼠体内抑制HBV的复制和抗原表达。 相似文献
64.
慢性肝病和肝癌中HCV核心区三种寡肽抗原的抗体检测 总被引:1,自引:0,他引:1
检测148例慢性肝病和肝癌患者血清中丙型肝炎病毒核心区3种寡肽抗原的抗体,结果显示其阳性率在慢性迁延型肝炎、慢性活动型肝炎、肝炎肝硬化和原发性肝癌患者分别为7.7%,23.1%,,23.5%和16.3%。在抗体阳性者中80%以上有乙型肝炎病毒感染证据,提示我国HBV和HVC重叠感染较为常见。 相似文献
65.
精子洗涤对精液中HBV DNA含量的影响 总被引:8,自引:0,他引:8
目的:检查HBV感染者精液是否存在乙型肝炎病毒(HBV),探讨精子洗涤是否能去除其中的HBV DNA。方法:用实时荧光定量PCR(FQ-PCR)法检测57名血清HBsAg阳性患者精液中HBV DNA,采用Percoll非连续梯度离心及上游法分离其中21份精液,并对洗涤后标本进行HBV DNA检测。结果:62份精液标本中有15份HBV DNA阳性,阳性率为24.19%;21份用于洗涤的精液标本中有,有7份HBV DNA阳性,洗涤后仍有6份标本阳性。结论:部分HBV感染者精液具有传染性,精子洗涤不能完全去除精液中的乙肝病毒。将HBV感染者的精液用于人工授精或体外受精应慎重。 相似文献
66.
Mary Ellen Turner Kanwal Kher Tamara Rakusan Lawrence D’Angelo Sudesh Kapur Dena Selby Patricio E. Ray 《Pediatric nephrology (Berlin, Germany)》1997,11(2):161-163
We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency
virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently
developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children
presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was
treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria
and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters,
both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains
unknown and the role of HIV infection in its pathogenesis, although possible, is unclear.
Received March 5, 1996; received in revised form and accepted October 15, 1996 相似文献
67.
Data on the prevalence of antibody to hepatitis C virus among 278 subjects in an institution for the mentally handicapped were analysed by risk factors. A prevalence of 4% was found, higher than blood donors belonging to the same area (1.4%). No differences in prevalence with regard the length of residence, age, sex, degree of retardation or for presence of HBV markers were observed. 相似文献
68.
丙型肝炎(HC)86例,经临床观察发现其临床特点是:①潜伏期长短不一,长者120d短者26d,平均40.5±14.5d。②起病缓慢而隐匿。③病状轻,体征不明显,病程长。④肝功能损害程度与症状、体征不一致,往往不能及时诊治。⑤肝功能恢复慢,ALT、AST有持续升高或反复异常。⑥治疗:用治疗肝炎的常用药物仅对改善症状有一定作用,对缩短病程及肝功能恢复无效。 相似文献
69.
登革病毒感染后小鼠细胞免疫功能的动态变化 总被引:2,自引:0,他引:2
从登革Ⅱ型病毒感染成年BALB/c小鼠为模型,观察感染后不同时间机体细胞免疫反应的变化。结果表明:感染后7-14d免疫功能处于激活状态,表现为腹腔巨噬细胞的吞噬功能和脾淋巴细胞对ConA的反应及IL-2产生水平都明显高于对照组,感染21d后免疫功能则转为抑制状态,上棕免疫反应明显低于对照组,脾中的L3T4^+细胞亚群的百分比逐渐下降;相反,LYT2^+细胞亚群的百分比逐渐升高,这种抑制现象可维持到 相似文献
70.
Tomoyuki TAKANO Masaki OHNO Tsunekazu YAMANO Morimi SHIMADA 《Congenital anomalies》1991,31(3):129-139
Abstract This study was undertaken to elucidate the pathogenesis of the hydrocephalus and aqueductal stenosis induced by intracerebral mumps virus inoculation in suckling hamsters.
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus. 相似文献
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus. 相似文献