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Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed.  相似文献   
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BACKGROUND: Little is known about the frequency of and the features associated with recurrent anaphylaxis in pediatric populations. During 1994 to 1996, we enrolled 76 children affected by anaphylaxis in a prospective study to analyze their clinical and allergic features. OBJECTIVE: To undertake a follow-up study of these children to ascertain how many experienced a recurrence of anaphylaxis. METHODS: After a mean interval of 7 years, a pediatric allergist conducted a telephone interview of patients who had been enrolled in our 1994-1996 study. RESULTS: A telephone interview was successfully completed in 46 (61%) of the 76 patients who had been enrolled in our 1994-1996 study. Of these 46 patients, 14 (30%) had experienced a recurrence of anaphylaxis. Children with atopic dermatitis either during 1994 to 1996 (64% vs 34%; P = .04) or at the time of the current study (43% vs 16%; P = .03) and those with urticaria-angioedema at the time of the current study (93% vs 31%; P = .0002) were found to be at a significantly higher risk for recurrent anaphylaxis. Furthermore, those children who were sensitive to at least 1 food allergen during 1994 to 1996 were more likely to have experienced a recurrence of anaphylaxis (93% vs 56%; P < .04). CONCLUSIONS: This study suggests that patients may have a greater risk of recurrence of anaphylaxis if they have atopic dermatitis, urticaria-angioedema, or at least 1 positive result of skin prick tests to food allergens.  相似文献   
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To investigate the intra-hepatic activation of the IFN system in patients affected by chronic HCV-infection in comparison with that observed in a non-infectious liver disease such as non-alcoholic steatohepatitis, we measured the liver steady state mRNA levels of interferon-alpha, interferon-beta and interferon-gamma as well as of IFN-related genes (IFNAR-1, STAT1alpha, PKR, 2-5 AS, IRF-1, ICE and IL-18). In HCV-infected subjects, possible correlations of these parameters with viral load and liver injury were also analyzed. Twenty-four chronic untreated HCV-infected subjects and seven patients with non-alcoholic steatohepatitis were enrolled in the study. Liver biopsies were graded according to Knodell scores. Intra-hepatic mRNA levels of IFNs and related genes were assessed by semi-quantitative RT-PCR. In comparison with non-alcoholic steatohepatitis, in HCV-infected subjects IFN-alpha and -beta mRNA levels were significantly lower, whereas IFN-gamma, IFNAR-1, STAT1alpha IRF-1, and IL-18 mRNA were upregulated. Moreover, IFN-gamma mRNA steady state levels were correlated positively with those of IFNAR-1, IRF-1, and IL-18, suggesting a coordinated induction of these genes. Although plasma viral load was correlated inversely with IL-18-specific mRNA, viral load was not related to liver injury. IFN-gamma and IRF-1 mRNA levels were correlated positively with ALT, but not with the grading or staging. Conversely, IFN-alpha and -beta mRNA levels were higher in livers with lower staging scores. These findings support the hypothesis that in chronic HCV infection there is an imbalance between an upregulated IFN-gamma system and a downregulated IFN-alpha and -beta system, probably due to a mixed effect exerted by HCV-specific and inflammatory non-specific factors.  相似文献   
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Around 25% of hereditary breast and ovarian cancer families have mutations in the BRCA1 and BRCA2 genes. The search for other genes has until now failed, probably because there is not one single BRCAX gene, but rather various genes that may each be responsible for a small number of breast cancer families and/or may interact according to a polygenic model. We have studied 50 tumors from probands belonging to non-BRCA1/2 breast cancer families (BRCAX), using 25 immunohistochemical markers. The objective was to classify these tumors and confirm that they are heterogeneous. Unsupervised cluster analysis showed the existence of the following two main groups of tumors: high-grade and estrogen receptor (ER)-negative tumors (50%), and low-grade and ER-positive tumors (50%). In addition we identified five subgroups, three among the high-grade and two among the low-grade groups; one overexpressing HER-2 (18%); one with a basal-like phenotype (14%); one with a normal breast-like phenotype (18%); a luminal A subgroup (36%), and a luminal B subgroup (14%). Hypermethylation of the BRCA1 gene was observed in 42% of the cases, spread across all five subgroups, but only 37% of those had loss of heterozygosity as well. These latter cases were all clustered in the high-grade group and the majority of them in the basal-like subgroup. Our results show that familial non-BRCA1/2 tumors are heterogeneous and suggest a polygenic model for explaining the majority of BRCAX families. In addition we have defined a subset of them that have somatic inactivation of the BRCA1 gene.  相似文献   
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Two x-ray phase contrast imaging techniques are compared in a quantitative way for future mammographic applications: diffraction enhanced imaging (DEI) and phase propagation imaging (PPI). DEI involves, downstream of the sample, an analyser crystal acting as an angular filter for x-rays refracted by the sample. PPI simply uses the propagation (Fresnel diffraction) of the monochromatic and partially coherent x-ray beam over large distances. The information given by the two techniques is assessed by theoretical simulations and compared at the level of the experimental results for different kinds of samples (phantoms and real tissues). The imaging parameters such as the energy, the angular position of the analyser crystal in the DEI case or the sample to detector distance in the PPI case were varied in order to optimize the image quality in terms of contrast, visibility and figure of merit.  相似文献   
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