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Problem: The Leaders in Indigenous Medical Education (LIME) Network aims to improve the quality and effectiveness of Indigenous health in medical education as well as best practice in the recruitment, retention, and graduation of Indigenous medical students. Intervention: In this article we explore the utility of Etienne Wenger's “communities of practice” (CoP) concept in providing a theoretical framework to better understand the LIME Network as a form of social infrastructure to further knowledge and innovation in this important area of health care education reform. Context: The Network operates across all medical schools in Australia and New Zealand. Outcome: Utilizing a model of evaluation of communities of practice developed by Fung-Kee-Fung et al., we seek to analyze the outcomes of the LIME Network as a CoP and assess its approach and contribution to improving the implementation of Indigenous health in the medical curriculum and the graduation of Indigenous medical students. Lessons Learned: By reflecting on the Network through a community of practice lens, this article highlights the synthesis between the LIME Network and Wenger's theory and provides a framework with which to measure Network outputs. It also posits an opportunity to better capture the impact of Network activities into the future to ensure that it remains a relevant and sustainable entity.  相似文献   
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Reduced glutathione (GSH) has been demonstrated in benign and malignant human breast lesions using a newly developed histofluorescence technique. GSH was present in every lesion and in each case was localised to the epithelium. A semi-quantitative assessment revealed a moderate amount of GSH in normal epithelium and fibroadenoma and a high level in apocrine metaplasia, epitheliosis and intraduct carcinoma. Invasive ductal carcinoma contained a variable amount of GSH. Correlation between fluorescence intensity and histological grade of ductal carcinomas was almost statistically significant but a relationship to oestrogen receptor status was not detected. The rapid assessment of GSH in breast cancer may aid in the selection of optimum chemotherapeutic regimens.  相似文献   
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OBJECTIVE: To ascertain whether tendon samples harvested from patients with calcific insertional Achilles tendinopathy showed features of failed healing response, and whether abnormal quantities of type II collagen had been produced in that area by these tenocytes. DESIGN: Comparative laboratory study. DESIGN: University teaching hospitals. PATIENTS: Tendon samples were harvested from eight otherwise healthy male individuals (average age 47.5+/-8.4 years, range 38 to 60) who were operated for calcific insertional Achilles tendinopathy and from nine male patients who died of cardiovascular events (mean age 63.1+/-10.9 years) while in hospital. INTERVENTIONS: Open surgery for calcific insertional Achilles tendinopathy. MAIN OUTCOME MEASURE: Semi-quantitative histochemical, immunohistochemical, and immunocytochemical methods to ascertain whether tendinopathic tendons were morphologically different from control tendons, and whether abnormal types of collagen were produced. RESULTS: Tenocytes from tendons from patients with calcific insertional Achilles tendinopathy exhibit chondral metaplasia, and produce abnormally high quantities of collagen type II and III. CONCLUSIONS: The altered production of collagen may be one reason for the histopathological alterations described in the present study. Areas of calcific insertional Achilles tendinopathy have been subjected to abnormal loads. These tendons may be less resistant to tensile forces. Further studies should investigate why some tendons undergo these changes.  相似文献   
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It has been postulated that patients with ulcerative colitis (UC) have altered reactivity of gut-associated lymphoid tissue. In such cases there is intense infiltration of the mucosa with immune competent cells and associated tissue damage. We have shown previously that the dietary supplementation with the n-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) results in significant systemic immune suppression. The aim of this study, therefore, was to evaluate the in situ effect of n-3 PUFAs on distal proctocolitis. Each patient received either fish oil extract (EPA 3.2 g, DHA 2.4 g) (n = 9) or sunflower oil (n = 9) daily in a double blind manner for six months. Monthly assessment included: (1) disease activity using clinical, sigmoidoscopic, and histological scores and (2) immunohistochemical analysis (immunoglobulins, CD profiles) of rectal biopsy specimens (before and after six months supplementation) using monoclonal antibodies and quantitative computer-assisted video image analysis. Prior to receiving supplementation, patients with proctocolitis (n = 18) showed significantly higher numbers of cells expressing CD3 (pan T cells) and HLA-DR and IgM containing cells compared with non-colitic controls (n = 8). Six months supplementation with n-3 PUFAs resulted in significant reduction in the number of cells expressing CD3 and HLA and the percentage of cells containing IgM. There was no significant change in the CD20 nor the percentage of IgG or IgA containing cells in either group of patients with procto-colitis. In patients receiving n-3 PUFA supplementation, there was improvement in the disease activity and histological scores, compared with pretreatment evaluation. This study has demonstrated both evidence of suppression of in situ immune reactivity and concurrent reduction in disease activity in patients with proctocolitis receiving n-3 PUFA supplementation. This may have important implication for therapy in patients with ulcerative colitis.  相似文献   
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Sperm quality in Hodgkin's disease versus non-Hodgkin's lymphoma   总被引:3,自引:4,他引:3  
The study was conducted to determine the deleterious effect of lymphoma disease on spermatogenesis and to evaluate the possibility that the disease is mediated primarily by inherent mechanisms in Hodgkin's disease and non-Hodgkin's lymphoma patients. A total of 89 patients with lymphoma disease (Hodgkin's and non-Hodgkin's) were referred for sperm preservation prior to adjuvant treatments. A comparison was made of pre- and post-thaw sperm quality between lymphoma patients and healthy volunteers who applied for sperm donation. This was followed by further assessment of the differences between patients with Hodgkin's disease and non-Hodgkin's lymphoma in terms of sperm variables, clinical parameters and blood hormone concentrations. It was found that patients with lymphoma disease had significantly impaired pre-freeze and post-thaw sperm quality compared with that of healthy volunteers. Patients with non-Hodgkin's lymphoma had spermatozoa of higher quality than patients with Hodgkin's disease. No differences were found in the clinical or hormonal parameters between these two groups. As expected, reduced testicular size and abnormal testicular consistency were correlated with decreased sperm quality. The mere presence of cancer disease has a direct negative effect on spermatogenesis, which is probably not related to incidental side-effects. A variable degree of impairment should be expected with different categories of cancer.   相似文献   
9.
The thymus in systemic sclerosis   总被引:1,自引:0,他引:1  
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10.
Type I collagen is the main collagen in tendons; type III collagen is present in small amounts. Ruptured Achilles tendons contain a significantly greater proportion of type Ill collagen, which predisposes them to rupture. We used an in vitro model to determine whether tenocytes from Achilles tendons that were ruptured (N = 22), nonruptured (N = 7), tendinopathic (N = 12), and fetal (N = 8) show different behavior. Samples of Achilles tendon were digested with collagenase and the released tenocytes were collected. Primary tenocyte cultures were established and subsequently cultured onto glass coverslips. Once a confluent monolayer was obtained, the cell populations were "wounded" by scraping a pipette tip along the surface. The cultures were further incubated for either 1, 4, 8, 12, 16, or 24 hours, and production of types I and II collagen was assessed by immunostaining. In cultures from ruptured and tendinopathic tendons, there was increased production of type Ill collagen. Athletic participation places excess stress on the Achilles tendon, which could potentially lead to areas of microtrauma within the tendon. These areas may heal by the production of type III collagen, which is an abnormal healing response. Accumulation of such episodes of microtrauma could resuit in a critical point where the resistance of the tissue to tensile forces is compromised and tendon rupture occurs.  相似文献   
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