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991.
目的探讨树突状细胞表面特异性非整联蛋白(DC—SIGN)及其同源物(DC-SIGNR)外显子4遗传多态性在中国裔丙型肝炎患者中是否存在遗传易感性。方法采用PCR结合DNA测序对300例丙型肝炎患者和520名健康人的DC-SIGN和DC-SIGNR外显子4重复序列多态性进行基因分型和测序分析。结果DC—SIGN外显子4基因型与等位基因频率在丙型肝炎患者和健康人群间差异无统计学意义(P〉0.05)。DC-SIGNR外显子4等位基因的频率差异也无统计学意义(P〉0.05);但9/5基因型分布频率在丙型肝炎患者和健康人群间的差异有统计学意义(P〈0.05)。结论DC-SIGN外显子4遗传多态性与HCV感染易感性无明显相关性;9/5基因型DC-SIGNR外显子4在丙型肝炎患者中的分布频率较高,可能与HCV感染的易感性相关,值得进一步研究。 相似文献
992.
Erhart A Thang ND Hung NQ Toi le V Hung le X Tuy TQ Cong le D Speybroeck N Coosemans M D'Alessandro U 《The American journal of tropical medicine and hygiene》2004,70(2):110-118
Forest malaria is a complex but common phenomenon occurring in southeast Asia. We studied its epidemiology through a prospective community-based study in central Vietnam. A total of 585 individuals were followed for two years by active case detection and biannual cross-sectional surveys. The prevalence of antibodies to Plasmodium falciparum was constantly about 20% across surveys and the incidence rate of clinical episodes of P. falciparum malaria was 0.11/person-year. Multivariate analysis showed that regular forest activity was the main risk factor for clinical malaria and malaria infections. Untreated bed nets had a significant protective effect (60%), except for people regularly sleeping in the forest. The population-attributable fraction for regular forest activity was estimated to be 53%. Our results confirm the major role played by forest activity on the malaria burden in this area and provide the basis for targeting control activities to forest workers. New interventions based on insecticide-treated materials need to be urgently evaluated. 相似文献
993.
血清抗AT1、α1、β1受体自身抗体在高血压合并肾损害患者的初步研究 总被引:3,自引:1,他引:3
目的探讨抗血管紧张素Ⅱ受体1型(AT1受体)受体,α1肾上腺素受体(α1受体)、β1肾上腺素受体(β1受体)自身抗体是否与高血压病合并肾损害有关。方法以合成的β1、AT1、α1受体多肽片段为抗原,应用酶联免疫吸附测定(ELISA)技术,检测56例高血压并肾损害患者和58例高血压无肾损患者及40例正常人血清中抗G蛋白偶联型β1、AT1、α1受体自身抗体。结果高血压病并肾损害组抗β1、AT1、α1受体抗体阳性率分别为67.9%(38/56)、46.4%(26/56)、46.4%(26/56),明显高于高血压无肾损害组的19%(11/58)、15.5%(9/58)、12.1%(7/58)和及正常对照组的15%(6/40)、10%(4/40)、12.5%(5/40),比较具有显著性差异(P<0.01)。结论抗G蛋白偶联型受体自身抗体可能与高血压合并肾损害发病有关。 相似文献
994.
995.
Renou C Halfon P Pol S Cacoub P Jouve E Bronowicki JP Arpurt JP Rifflet H Picon M Causse X Canva V Denis J Tran A Bourliére M Ouzan D Pariente A Dantin S Alric L Cartier V Reville M Caillat-Zucman S 《Gut》2002,51(4):585-590
OBJECTIVE: A significant proportion of individuals with chronic hepatitis C virus (HCV) infection have persistently normal alanine aminotransferase (ALT) levels. Although data are controversial, such patients usually have weaker histological damage and a lower progression rate of fibrosis. The aims of this study were: (1) to compare demographic, virological, and histological parameters of HCV patients with normal ALT values with those of HCV patients with elevated ALT levels; and (2) to determine whether HLA class II alleles contribute to the persistence of normal ALT levels in HCV patients. PATIENTS AND METHODS: Eighty three patients with chronic HCV infection and persistently normal ALT values (group 1) and 233 patients with chronic HCV infection and elevated ALT levels (group 2) were studied. Histological features were expressed using Knodell and Metavir scores. HLA DRB1* and DQB1* genotyping was performed using hybridisation with sequence specific oligonucleotides after genomic amplification. The kappa2 and Fisher's exact tests were used to compare discrete variables and phenotype frequencies between the two groups, and Wilcoxon's test was used for continuous variables. A multivariate logistic regression model was used to determine which variables predicted normal ALT values. RESULTS: ALT levels were correlated with the severity of liver damage. In group 1, 93% of patients had an F0 or F1 Metavir index of fibrosis compared with 47% of patients in group 2 (p<0.001). A longer duration of infection (p<0.001) and increased DRB1*11 phenotype frequency (pc=0.03) were observed among patients with normal ALT. The two groups did not differ with regard to the mode of contamination or viral genotype. After logistic regression, young age (p=0.0008), female sex (p=0.01), long duration of infection (p=0.0001), and HLA DRB1*11 (p=0.050) were more strongly associated with persistence of normal ALT. CONCLUSIONS: Our study confirms that patients with chronic hepatitis C and normal ALT levels have less severe liver disease than those with elevated ALT levels. This particular biochemical outcome may be explained, at least in part, by host immunogenetic factors such as the presence of HLA-DRB1*11. 相似文献
996.
997.
998.
Barcus MJ Hien TT White NJ Laras K Farrar J Schwartz IK Corwin A Baird JK 《The American journal of tropical medicine and hygiene》2002,66(2):140-142
We investigated the prevalence of infection with hepatitis B virus among adult Vietnamese patients hospitalized for severe Plasmodiumfalciparum malaria. Sera from patients admitted with severe malaria in Ho Chi Minh City, Vietnam, between May 1991 and January 1996 were assayed for hepatitis B surface antigen (HB(s)Ag) by a commercial enzyme-linked immunosorbent assay kit. The overall prevalence of HB(s)Ag was 23.77% (77 of 324). This was higher than reported estimates of prevalence in the general catchment population for the study hospital (mean, 9.8%; range, 9-16%). No association was found between risk of death caused by severe malaria and HB(s)Ag. Patients admitted with cerebral malaria had a slightly greater risk of registering positive for HB(s)Ag (relative risk, 1.28; 95% confidence interval, 1.04-1.58) relative to other manifestations of severe malaria. Chronic infection with hepatitis B virus may be a risk factor for severe malaria. 相似文献
999.
1000.
Stefan Schreiber Konrad Aden Joana P. Bernardes Claudio Conrad Florian Tran Hanna Höper Valery Volk Neha Mishra Johanna Ira Blase Susanna Nikolaus Johannes Bethge Tanja Kühbacher Christoph Röcken Minhu Chen Ian Cottingham Niclas Petri Birgitte B. Rasmussen Juliane Lokau Philip Rosenstiel 《Gastroenterology》2021,160(7):2354-2366.e11