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101.
K N Tsiquaye B Portmann G Tovey H Kessler S Hu X Z Lu A J Zuckerman J Craske R Williams 《Journal of medical virology》1983,11(3):179-189
There are reports in the literature that infection with hepatitis A virus in hepatitis B carriers can result in resolution of the carrier state. In an attempt to induce clearance of the carrier state of hepatitis B virus in two persistently infected chimpanzees, the chimpanzees were infused with documented non-A, non-B infectious material. Biochemical and histopathological evidence of hepatitis was accompanied by the unique abnormalities of endoplasmic reticulum associated with non-A, non-B hepatitis in the chimpanzees. Elevation of alanine aminotransferase was accompanied by fourfold reduction in one chimpanzee and sixfold reduction in the other in the plasma levels of HBV-associated DNA polymerase activity and simultaneously by twofold reduction in the concentration of hepatitis B surface antigen in both chimpanzees. A mediator may account for these changes in markers of hepatitis B virus infection, and this mechanism may also explain the occurrence of spontaneous regression in some persistently infected carriers. The significance of transient red cell anaemia in non-A, non-B hepatitis, which was observed in one of the chimpanzees, is yet to be established. 相似文献
102.
慢性乙肝患者杀伤性免疫细胞功能的研究 总被引:8,自引:0,他引:8
通过对44例病毒性肝炎患者T细胞亚群,NK细胞活性与LAK细胞活性的观察,探讨了在慢性乙型肝炎病毒复制与非复制状态下的杀伤性细胞活性。结果表明:在乙肝病毒的高复制状态下,CD8^+细胞数增加,CD4^+/CD8^+比例显著下降;NK细胞活性与LAK细胞活性也明显低下,且在HBeAg与HBVDNA阳性组中,NK活性与LAK活性的改变与HBeAg的P/N值变化呈显著负相关,而NK活性与LAK活性变化则 相似文献
103.
104.
The importance of maternal infections with Toxoplasma gondii , cytomegalovirus (CMV), Parvovirus B19, respiratory syncytial virus (RSV), and influenza A and B on fetal IgE synthesis was studied in 153 pregnant women. No case of specific IgM activity or viral DNA in cord blood, indicating a congenital infection, was found. From gestational week 15 to delivery, maternal IgG-Ab seroconversion to Parvovirus B19, RSV, influenza A, or influenza B occurred in 47 women. At delivery, serologic signs of past infection with T. gondii were observed in 29 (19%) women, and the corresponding figure for CMV was 117 (77%). The number of women with positive IgG seroconversion during pregnancy or positive IgG-Ab activity toward the studied infectious agents at delivery did not differ significantly among infants with an increased (≥1.3 kU/1; n =51) or with an undetectable (<0.1 kU/l; n =102) cord-blood IgE level. These results show that genetic and other environmental factors probably have a greater influence on fetal IgE synthesis than do maternal infections during pregnancy. 相似文献
105.
1993年9月以来,用自血光量子治疗各型病毒性肝炎72例,结果所有患者症状均明显好转或消失,SB异常者恢复正常和有效分别占66.7%和90.2%,ALT异常者恢复正常和有效分别为77.4%和100%,血清白蛋白平均上升4.2g/L,球蛋白下降4.6g/L,三项凝血功能(PT、HPT、KPTT)测定结果表明量子血疗不会引起或加重肝炎患者的凝血障碍。61例乙型肝炎患者HBeAg和HBsAg的阴转率分别达59.3%和15%。 相似文献
106.
E. P. Mauser-Bunschoten G. Roosendaal H. M. van den Berg D. Bresters A. A. J. van Drimmelen H. T. M. Cuypers P. N. Lelie H. W. Reesink C. L. Der Van Poel 《Journal of medical virology》1995,45(3):241-246
Serum samples from 316 patients visiting the Dutch National Hemophilia Center were collected from 1979 to 1993 and stored at ?30°C. Patients were placed into three different groups: (1) patients ever treated with large pool non-hepatitis C virus (HCV)-safe concentrate (n=179); (2) patients treated with cryoprecipitate (n = 125); and (3) patients treated exclusively with HCV-save concentrate (n=12). In order to examine the prevalence of HCV infection in the different treatment groups serum samples were tested retrospectively for anti-HCV antibody using second generation enzyme-linked immunosorbent assay (ELISA) and recombinant immunoblot assay (RIBA-2). Significant differences in the prevalence of HCV infection were found between these 3 groups (group 1: 99%, group 2: 66%, group 3: 0%). The safety of currently administered clotting products is demonstrated in 57 patients who remained without HCV markers between 1989 and 1993. To examine the natural course of HCV infection fresh-frozen plasma samples were obtained recently from a subgroup of 277 hemophilia patients for HCV-RNA detection by a well-validated cDNA-PCR assay. In contrast to other reports, no evidence was found for seronegative HCV carriers. None of 52 patients without anti-HCV had detectable HCV-RNA. Of 225 patients with anti-HCV, 182 (81%) were HCV-RNA positive. None of 39 anti-HCV positive patients with a negative HCV-RNA reaction had serum alanine aminotransferase (ALT) levels above 50 U/l, whereas 44% of HCV-RNA positive patients had persistently elevated ALT levels above 50 U/l. These results indicate that 20% of hemophilia patients who have been infected with HCV in the past eliminated the virus or have viral replication below the detection limit of polymerase chain reaction (PCR) without biochemical evidence of liver damage. © 1995 Wiley-Liss, inc. 相似文献
107.
Yasunari Nakamoto Shuichi Kaneko Masao Honda Masashi Unoura Jaehun Cheong Akihisa Harada Kouji Matsushima Kenichi Kobayashi Seishi Murakami 《Journal of medical virology》1994,42(4):374-379
The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis. © 1994 Wiley-Liss, Inc. 相似文献
108.
109.
J A Rump D Jakschiess U Walker M Schlesier P von Wussow H H Peter 《Clinical and experimental immunology》1995,101(1):89-93
The underlying immunopathogenic mechanism of CVID has been suspected to involve a chronic viral infection or an autoimmune condition. However, formal proof of viral infection is lacking. Measurement of MxA-protein in leucocyte lysates is a sensitive test for evaluating the activation of the host's interferon system. Both viral infections and autoimmune diseases such as systemic lupus erythematosus (SLE) strongly induce MxA-protein in peripheral leucocytes. We therefore examined 15 patients with longlasting hypogammaglobulinaemia for MxA-protein induction in vivo: 13 patients suffered from CVID, one from hyper-IgM syndrome, and one patient had chronic B lymphocytic leukaemia associated with immunoglobulin deficiency and chronic papilloma virus infection (condylomata accuminata). Only the latter patient exhibited a strong MxA-protein expression; two CVID patients were borderline positive, and the remaining 12 patients including the hyper-IgM syndrome were MxA-protein-negative. There was no relationship between MxA expression and low CD4/CD8 ratios or increased CD8/CD57+ T cell counts, although both conditions are often observed in CVID as well as in chronic viral infections. When exposed in vitro to interferon-alpha (IFN-alpha), peripheral blood leucocytes of four MxA-negative patients were capable of producing normal amounts of MxA-protein. Taken together, these results argue against a viral or autoimmune pathogenesis of CVID. 相似文献
110.
Dialysable transfer factor (TF) was given in 10 paediatric patients with severe atopic dermatitis (AD). Ten patients with AD, matched for age and severity of disease, served as controls.
Prior to the therapy with TF and at weekly intervals thereafter, T- and B-cells in the blood, PHA-stimulation, total IgE and specific IgE antibodies to inhalant and food antigens were determined. Therapy with TF was followed by IgE depression in 8/10 patients and was most pronounced in three patients with initially high levels. Some decrease of IgE levels was seen in four controls also, none of them, however, fell to normal levels as was seen in two of the treated patients.
Specific IgE levels decreased slightly, but always remained within the pathological range. T-cell counts in the blood increased in 2/10 cases as well as PHA-stimulation. B-cell counts remained within normal limits. Clinical improvement was seen in one patient, five improved slightly and four remained unchanged.
Our results indicate, that transfer factor can lower total IgE levels in cases with atopic dermatis. The effect is most marked in patients with high total IgE levels. Skin involvement, however, does not closely follow in vitro findings. 相似文献
Prior to the therapy with TF and at weekly intervals thereafter, T- and B-cells in the blood, PHA-stimulation, total IgE and specific IgE antibodies to inhalant and food antigens were determined. Therapy with TF was followed by IgE depression in 8/10 patients and was most pronounced in three patients with initially high levels. Some decrease of IgE levels was seen in four controls also, none of them, however, fell to normal levels as was seen in two of the treated patients.
Specific IgE levels decreased slightly, but always remained within the pathological range. T-cell counts in the blood increased in 2/10 cases as well as PHA-stimulation. B-cell counts remained within normal limits. Clinical improvement was seen in one patient, five improved slightly and four remained unchanged.
Our results indicate, that transfer factor can lower total IgE levels in cases with atopic dermatis. The effect is most marked in patients with high total IgE levels. Skin involvement, however, does not closely follow in vitro findings. 相似文献