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991.
The aim was to assess the specificity and functional significance of liver-infiltrating and peripheral blood T cells in chronic hepatitis C. Peripheral blood mononuclear cells hepatitis C virus from 50 of 58 (86.2%) patients with chronic hepatitis C virus infection and 6 of 28 (21.4%) controls showed a proliferative T cell response to at least one of 16 synthetic peptides covering highly conserved regions of the core, envelope (El) and non-structural regions (NS4) of hepatitis C virus. However, six immunodominant peptides were exclusively recognized by the proliferating blood mononuclear cells from 46 patients with chronic hepatitis C virus infection (79.3%). Fine specificity and HLA-restriction were studied with 15 peptide-specific CD4+ T cell lines and 23 T cell clones isolated from liver tissue and peripheral blood of 12 patients with chronic hepatitis C. It was demonstrated that the peptide-specific response of CD4+ T cells was restricted to the presence of autologous accessory cells and HLA-DR and -DP molecules. Eight peptide-specific T cell lines and five T cell clones derived from liver tissue and peripheral blood, released interferon-gamma (200-6600 pg/ml) and tumor necrosis factor-alpha (100-400 pg/ml) and no or little interleukin-4 (< 140 pg/ml) after peptide-specific or mitogeneic stimulation, thus resembling a Th1-like cytokine profile. Patients with active liver disease showed significantly higher proliferative responses to hepatitis C virus core peptides than asymptomatic hepatitis C virus carriers or complete responders to interferon therapy. In conclusion, class II-restricted CD4+ T cell responses to some immunodominant epitopes within the hepatitis core region correlated with disease activity in chronic hepatitis C virus infection. Functionally, liver-infiltrating and peripheral blood T cells released Th1-like cytokines in response to the specific stimulus. Thus, it can be suggested that CD4+ T cells can mediate the pathogenesis of chronic hepatitis C virus induced liver disease.  相似文献   
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The focus of training in a competency-based residency program is on ensuring that all residents attain prespecified levels of competence for particular objectives in each training activity. The authors examine the components of a competency-based program and describe the phases of development that their department went through in creating such a program. They conclude that the competency-based training model directly faces the issue of certifying competence by holding itself accountable in a demonstrable way for ensuring that its residents have mastered specific areas of knowledge, skills, and attitudes.  相似文献   
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A case of lipomembranous polycystic osteodysplasia is presented. The clinical features were characterized by multiple cystic changes of the bones and progressive psychomotor retardation. Although the diagnosis of polyostotic fibrous dysplasia of bone was made first because of expanded tumorlike lesions in bones, pathology of bone and bone marrow confirmed the diagnosis of lipomembranous polycystic osteodysplasia. Light microscopy showed a great number of peculiar undulating membranous structures in the adipose tissue. With the electron microscope the membrane seemed to be composed of an accumulation of endoplasmic reticulum-like tubular profiles. They appear first, in close connection with fat droplets, within the mesenchymal cell.  相似文献   
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A patient with cutaneous necrotizing vasculitis had chronic urticaria associated with multiple system involvement including arthralgias, glomerulonephritis, myositis, pseudotumor cerebri, and adenopathy. Persistent hypocomplementemia is noted with classic pathway activation. The syndrome recognized in this patient and those few individuals reported previously seems to constitute a distinct category of collagen-vascular disease.  相似文献   
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