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Cytomegalovirus (CMV) infection accelerates transplant vascular sclerosis (TVS) and chronic rejection (CR) in both human and animal solid organ transplantation models. The host/viral mechanisms involved in this process are unclear. We examine the role of the rat CMV (RCMV)-encoded chemokine-receptor R33 in the development of TVS using a rat heart transplantation/CR model. F344 heart grafts were transplanted heterotopically into Lewis recipients. The ability of RCMV lacking the R33 gene (RCMV-Deltar33) to accelerate CR/TVS (neointimal index, NI) was compared to wild-type (WT) RCMV. Allograft recipients were infected with 1 x 10(5) pfu RCMV or RCMV-Deltar33 on postoperative day (POD) 1. Grafts from RCMV-Deltar33-infected recipients demonstrated an accelerated time to allograft CR compared to grafts from uninfected recipients (POD = 56 vs. 90), this was slower than that seen in grafts from WT-RCMV-infected recipients (POD = 45). Similarly, the degree of graft TVS formation at terminal rejection in RMCV-Deltar33 infected recipients was more severe than uninfected recipients (NI = 63 vs. 45), yet not as severe as in WT-RCMV infected recipients (NI = 83). In parallel, RCMV-Deltar33 failed to induce vascular smooth muscle cell (SMC) migration in vitro, whereas WT-RCMV induced substantial migration. The RCMV-encoded chemokine-receptor r33 is critical for RCMV-accelerated TVS/CR and vascular SMC migration.  相似文献   
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BACKGROUND: Practitioners are being encouraged to base their clinical practice on research evidence. In order to do this, they must be aware of and use the sources of evidence. METHODS: A questionnaire survey was undertaken to establish GPs' awareness of research evidence in their clinical practice and, in fundholding practices, its influence on purchasing plans. Questionnaires were sent to 360 lead fundholders in North Thames Region and 440 of a random sample of the remaining general practitioners in the region for comparison. RESULTS: Questionnaires were returned by 62% of lead fundholders and 63% of GPs in the random sample. There was limited use of the electronic sources of clinical effectiveness. There was greater reported awareness of published sources of research evidence and fundholding GPs were significantly more likely to have referred to publications summarizing research evidence. CONCLUSIONS: GPs seem to make more use of published clinical effectiveness sources than the electronic databases. Consequently, they need educational and technical support if they are to make full use of the available sources of research evidence available in other media.   相似文献   
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Eighty-four cases of extraosseous Ewing's sarcoma (EOE) were found during the pathology review of the Intergroup Rhabdomyosarcoma Study I and II. Patients commonly presented during or after adolescence with the most common primary sites including the trunk, extremities, and retroperitoneum. Males were slightly more affected. Histologic sections of 74 tumors in the pathology repository were re-reviewed with attention to rosette formation (positive in 18 cases) and glycogen deposition (++ in 21, + in 36, +/- in 11, and - in 2 of 70 cases examined). Fourteen tumors (7 with rosettes and 7 without) were selected for immunohistochemical and ultrastructural studies, and 13 showed single or multiple neural markers (neuron-specific enolase in 8, S-100 protein in 6, and neurosecretory-type granules in 9). These possible cases of neural EOE could be divided into three subgroups: tumor with bidirectional neuroblastic and schwannian differentiation (5 cases), tumor with monodirectional neuroblastic differentiation (7 cases), and tumor with monodirectional schwannian differentiation (1 case). EOE with a neural nature may be categorized into a spectrum of peripheral primitive neuroectodermal tumors. Clinical, histopathologic, and biologic differences between this disease and conventional sympathetic neuroblastoma are discussed.  相似文献   
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Autoantibodies against the human asialoglycoprotein receptor (ASGPR) occur in the sera of patients with autoimmune liver disorders. Liver-infiltrating T cell clones that specifically recognize the ASGPR have been described in patients with autoimmune chronic active hepatitis (AI-CAH) and primary biliary cirrhosis (PBC). Recently, we have shown that peripheral blood mononuclear cells (PBMC) from patients with AI-CAH or PBC but not chronic viral hepatitis secreted anti-ASGPR antibodies in vitro. In this study we characterized the influence of liver-infiltrating T cells on the secretion of ASGPR-specific autoantibodies by autologous B cells in cell culture supernatants. T cell clones from liver biopsies of three patients with chronic autoimmune liver disorders (one with AI-CAH, two with PBC) were isolated and investigated for their proliferative response to soluble ASGPR and their helper function provided to autoantibody-secreting B lymphocytes. PBMC from these patients secreted autoantibodies spontaneously in their cell culture supernatants and showed a proliferative response to ASGPR. T cell-depleted PBMC, however, lacked spontaneous antibody secretion. Four CD4+CD8- liver-infiltrating T cell clones showed a proliferative response to ASGPR and also induced spontaneous anti-ASGPR antibody production in cell culture supernatants when added to autologous T cell depleted PBMC. Activated supernatants of these T cell clones failed to induce antibody production. None of seven CD4+CD8- and two CD4-CD8+ T cell clones non-responding to ASGPR provided this help for antibody secretion. Anti-ASGPR secretion in vitro could not be inhibited by the addition of MoAbs raised against monomorphic determinants on HLA class II molecules. The addition of purified ASGPR or polyclonal-activating pokeweed mitogen showed no influence on the production of autoantibodies in these cultures. These data show that B lymphocytes require T cell help for the production of ASGPR-specific antibodies. This help can be provided by ASGPR-responsive T helper cells via cellular interactions.  相似文献   
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One hundred patients undergoing abdominal surgery were included in this prospective study. The role of local application of Betadine, use of synthetic sutures, and use of low pressure subcutaneous suction drainage were evaluated in preventing post-operative wound infection. The infection rate was 15 per cent with Betadine, 15.4 per cent with prolene, 20 per cent with subcutaneous suction drainage and 30.8 per cent in the control group.KEY WORDS: Surgical wound infection, Betadine, Sutures, Infection control  相似文献   
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Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory.  相似文献   
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