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71.
The kinetics of serum viral responses and acute liver injury were studied during neonatal woodchuck hepatitis virus (WHV) infection in relation to the chronic or resolved outcome. The mean concentrations of serum WHV DNA and surface antigen were significantly higher by week 10 post infection in chronic infections compared to resolving infections, and diverged even further by the time of peak viral load development in serum (week 12). After week 12, these viral markers were detected less frequently with time and at lower concentrations in the resolved outcome. In both outcomes, mean serum activities of hepatic enzymes became increased significantly above baseline by weeks 10-12, peaked at week 14, and normalized by weeks 20-22, thus indicating transient acute liver injury. The increasing liver injury responses were comparable between outcomes at week 12, when serum viral load was markedly higher in the developing chronic infections. This suggested a deficiency in early non-cytolytic control of infection in the chronic outcome. At week 14, liver injury was significantly greater in the resolved outcome and associated with higher mean Fas ligand (FasL) and perforin messenger RNAs (mRNAs) in liver compared to the chronic outcome. This indicated greater immune-mediated killing of infected hepatocytes during resolution. Thus, chronicity as an outcome of neonatal WHV infection develops relatively early during the acute phase of infection due to reduced immune-mediated clearance of infected hepatocytes by both cytolytic and non-cytolytic processes.  相似文献   
72.
利用重组的丙型肝炎病毒非结构区(HCVNS5)抗原建立了酶免疫试验(EIA),对25例输血后丙型肝炎进行了不同区抗体及丙氨酸转氨酶(ALT)的动态研究,同时对156例慢性丙型肝炎患者血清进行HCVRNA和抗-NS5平行检测,两者符合率为64.1%。抗-NS5抗体首次检出时间为30~575天(182.9±168.5),晚于ALT异常和其他区抗体的出现时间。在感染后1,3,6,12和24个月后抗-NS5的阳性率分别为28%,40%,52%,68%和76%。抗-NS5的动态变化类型为四种:一过性阳性、间歇性阳性、持续性阳性和2年内持续阴性  相似文献   
73.
During a search for the aetiological agent of non-A non-B hepatitis, a precipitating antigen was detected in the sera of some patients during the acute phase of their illness. The antigen was detected by agar gel diffusion using antibody from convalescent sera obtained from patients with non-A non-B hepatitis, and from haemophiliac sera. The antigen was usually detected early in the patient's illness, disappearing as liver function tests returned to normal. In some patients specific antibody appeared during the convalescent phase of the disease. The antigen does not appear to be specific for non-A non-B hepatitis, as it could be detected with similar frequency in patients with hepatitis A or hepatitis B and some patients with other liver disorders. Biochemical and biophysical studies suggest that the antigen is probably an abnormal lipoprotein produced as a result of acute liver damage.  相似文献   
74.
Objective To investigate the level of the serum chemokine RANTES and its correlation with serum biochemical indices of liver function test, HBeAg and HBV DNA load in patients with chronic hepatitis B.Methods 144 patients with chronic hepatitis B (observed group) and 18 normal cases (control group) were enrolled in this study. The serum level of chemokine RANTES was detected with an ABC-ELISA assay. Statistical analysis was performed on the software of SPSS13.0. Results The serum chemokine RANTES level in the observed group (3930.12 ng/ml±2856.96) ng/ml was significantly higher than that in the control group (329.46 ng/ml±152.23) ng/ml. The results from the observed group indicated the positive correlation of serum RANTES level with indices of liver function test, including ALT (r=0. 197, P=0.018), AST(r=0.239, P=0.004) and TBil (r=0.316, P=0.001), but did not with PTA (r=-0.078, P=0.357). Neither difference of serum chemokine RANTES level between HBeAg-positive group and HBeAg-negative group nor that between high HBV DNA load group (≥105 copies/ml) and low HBV DNA load group (< 105 copies/ml) were statistically significant (P=0.407 and 0.185, respectively). Conclusions Serum chemokine RANTES level in patients with chronic hepatitis B elevates significantly and is not affected by HBeAg or HBV DNA load. Its positive correlation with indices of liver function test indicates that RANTES might play an important rule in the pathogenesis of chronic hepatitis B.  相似文献   
75.
An Epstein-Barr virus (EBV)-producer line, designated Akata, was established from a Japanese patient with Burkitt's lymphoma. The Akata line possessed the Burkitt's-type chromosome translocation, t(8q-; 14q+), and was derived from the tumor cell. Akata cells produced a large quantity of transforming virus upon treatment of cells with anti-immunoglobulin antibodies (Takada, 1984). Southern blot analysis of viral DNA indicated that the Akata EBV is nondefective and more representative of wild-type viruses. Akata cells should be useful as a source of EBV.  相似文献   
76.
Detection of HBV-DNA by in situ hybridization using a biotin-labeled probe   总被引:3,自引:0,他引:3  
A biotin-labeled DNA probe specific for hepatitis B virus (HBV) nucleotide sequences was hybridized in situ to liver tissue of 20 patients; 16 were chronic carriers of hepatitis B surface antigen (HBsAg) and 4 had no markers of HBV infection. HBV-DNA was also analyzed in the serum and the liver of these patients by spot and Southern blot hybridization, respectively. Liver specimens from six carriers were positive for HBV-DNA both by in situ and Southern blot hybridization; ten carriers were negative by in situ hybridization, and two of these were positive by Southern blot technique. The staining was granular, mainly cytoplasmic, limited to liver specimens containing replicative forms of HBV-DNA, and associated with detection of HBcAg in hepatocytes by immunofluorescence. The sensitivity of this technique was not sufficient to detect few copies of integrated HBV-DNA. The hybridization procedure was specific, as results were constantly negative in liver specimens of patients without markers of HBV infection, and no reaction was observed using DNA probes lacking HBV-DNA sequences. Detection of HBV-DNA by in situ hybridization, using a biotinylated probe, is a rapid, reproducible, and specific histochemical method. Currently available biotinylated probes are advantageous when absolute sensitivity is not the limiting factor, and they also facilitate studies of the cellular and subcellular distribution of HBV nucleic acids.  相似文献   
77.
78.
T. KAVA  L. A. LAITINEN 《Allergy》1985,40(1):42-47
Killed and live influenza virus vaccines were given to asthmatics and healthy subjects to investigate symptoms and alterations in their respiratory performance after vaccination. Polyvalent killed influenza virus vaccine was given to 16 asthmatics and live attenuated influenza virus vaccine to 23 asthmatics and 21 healthy subjects. Fourteen of the 16 asthmatics vaccinated with the killed vaccine displayed a significant rise in serum antibody level as measured by a single radial haemolysis in gel (SRH test). 11 of the 23 asthmatics and 14 of the 21 healthy subjects vaccinated with the live attenuated vaccine displayed a significant rise in the SRH test. Among the subjects with no measurable initial antibodies and with a significant rise in the SRH test, one asthmatic vaccinated with the killed vaccine experienced symptoms of common cold with fever and dyspnoea 1 week after vaccination. Three asthmatics and four healthy subjects vaccinated with live attenuated vaccine experienced mild symptoms, mainly rhinorrhoea, cough and sore throat 2 to 3 days after vaccination. No alterations in specific airway conductance in asthmatics or in healthy subjects were observed. We conclude that both killed and live attenuated influenza virus vaccines are tolerated well by asthmatics and appear to be safe for asthma patients.  相似文献   
79.
《Immunity》2022,55(3):542-556.e5
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80.
Infantile chronic recurrent parotitis (ICRP) has been attributed to multiple causes, including viral infections, and therefore its treatment remains empirical. Our aim was to evaluate the involvement of respiratory and oropharyngeal viruses in acute episodes of ICRP. Seventy children were studied, 50 patients and 20 age-matched controls, in a 2-year follow-up study. Saliva samples were taken from the parotid duct and analyzed by viral isolation and immunofluorescence for adenovirus (Ad), respiratory sincitial virus (RSV), parainfluenza virus (PI), influenza virus (Flu), Cytomegalovirus (CMV), and herpes simplex virus (HSV). Paired sera samples were tested by ELISA for anti-Epstein-Barr virus (EBV) IgG and anti-mumps IgM and IgG. Viral infections were detected in 7/50 (14%) cases of the ICRP group: one CMV; 2 Enteroviruses isolated in human embryonic lung fibroblast cells; 1 Flu A; and 3 mumps virus. No EBV seroconversions were detected. In the control group, 2 out of the 20 children had an asymptomatic mumps positive IgM titer. Our data indicate that the main respiratory and oropharyngeal viruses are not the cause of acute episodes of ICRP in Chilean children.  相似文献   
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