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It is important to consider the global context in which we operate and in which the association between society and health is to be explored. We are in a democratic world, with an economy that emphasises the market and a post-modern culture. The ancient elements of state, market and community are discernible in avaricious combinations and, if we are seeking a just social order, it is important that we apply appropriate analytical methods to social understanding. While social capital is an arresting term, its ambiguity limits its broad applicability and even makes it dangerous. Sir Richard Doll and his colleague Richard Peto once described epidemiological insight as a boundary-setting exercise, delimiting territory within which basic and clinical science can explore mechanisms. When it comes to matters of social and personal well-being, the same approach may serve us well. Social capital, defined differently by everyone who uses it, must be given some stability and be subject to good quality epidemiological research, not too dissimilar to that which has underpinned epidemiology's immense success in public health over the decades. Despite social capital's complexity, there are growing efforts to measure it and relate it to desirable social functions, but the ability of social capital to capture fully the subtle interplay of individuals and society so essential for their health and happiness is questionable.  相似文献   
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PURPOSE: Chromogenic in situ hybridization (CISH) is a new modification of the fluorescence in situ hybridization (FISH) technique for detection of oncogene amplification in archival tumor samples. In CISH, the oncogene probe is detected using a peroxidase reaction, allowing use of transmitted light microscopy. We compared detection of HER-2/neu amplification by CISH with a Food and Drug Administration-approved two-color FISH test in an interlaboratory setting. EXPERIMENTAL DESIGN: Formalin-fixed paraffin-embedded tumor samples from 197 breast cancers were analyzed for HER-2 amplification by CISH. Two-color FISH (PathVysion) CISH of 17 centromere was done if the observer considered it necessary to ascertain amplification status in tumors with borderline HER-2 CISH copy numbers. RESULTS: Paired CISH/FISH results were available from 192 (97%) of 197 cases, no clear difference in success rates of either method was observed. Centromere 17 CISH was considered necessary in seven tumors. CISH and two-color FISH results were concordant in 180 cases (93.8%). There were 92 and 88 tumors found HER-2 amplified and nonamplified, respectively, by both methods. Eight tumors were amplified by CISH but not by FISH, and four tumors exhibited the opposite condition (kappa coefficient 0.875). In 7 of 12 cases differences between the two methods could have related to a lack of CISH chromosome 17 information. The remaining cases were explained by difficult histology (ductal carcinoma in situ, poor representativity, dense lymphocytic infiltration, or intratumoral heterogeneity). CONCLUSIONS: These results indicate that CISH could provide an accurate and practical alternative to FISH for clinical diagnosis of HER-2/neu oncogene amplification in archival formalin-fixed breast cancer samples.  相似文献   
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PURPOSE: Vaccines, cytokines, and other biologic-based therapies are being developed as antineoplastic agents. Many of these agents are designed to induce an autologous immune response directed against the malignancy. In contrast, hematopoietic stem-cell transplantation is being developed as a form of allogeneic immunotherapy. This study tests the tolerance and antineoplastic activity of sequential infusions of partially HLA-matched allogeneic blood mononuclear cells (obtained from relatives) when administered outside of the context of a hematopoietic stem-cell transplantation. The cells are irradiated to prevent graft-versus-host disease. PATIENTS AND METHODS: Fifteen patients with relapsed or refractory malignancies for which no standard therapy was available were enrolled onto a clinical trial designed to assess the tolerability and antineoplastic effects of irradiated partially HLA-matched blood mononuclear cells obtained from relatives. RESULTS: There was disease regression in three patients with metastatic renal cell carcinoma during treatment. There was disease progression in six patients with metastatic renal cell carcinoma and two patients with metastatic melanoma during treatment. There was no change in disease state in several other patients. CONCLUSION: Irradiated allogeneic blood mononuclear cells administered outside the context of hematopoietic stem-cell transplantation may induce disease responses in patients with relapsed or refractory malignancies. Transfusion of irradiated allogeneic blood mononuclear cells should be developed further as a novel therapeutic antineoplastic approach.  相似文献   
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A 2-min focal application of Polyethylene Glycol (PEG) to injured mammalian spinal cords can offer significant yet limited restoration of functional and structural integrity. However, longer application of PEG has not been tested in similar injuries. In this study, isolated spinal cord white matter strips from adult guinea pigs were subjected to a 25 min exposure of PEG (MW: 2000; 50% w/w), with or without prior compression. When applied in a continuous steam, PEG, with a delay of about 6 min, suppressed the compound action potential (CAP) amplitude to 64+/-4% of the pre-PEG level in uninjured cords and to 64+/-7% in compressed cord strips. Both recovered to 70+/-5% (uninjured) and 88+/-11% (compressed) of the pre-PEG level following wash. When PEG was applied in a pulsatile manner, no significant decrease of CAP amplitude was observed. In summary, our results show that focal continuous application of PEG has minimal toxicity if applied for less than 5 min. Pulsatile application could extend this duration to at least 25 min with no toxicity. This study could be useful in determining the optimal protocol for the use of PEG in both animal research and human spinal cord victims.  相似文献   
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The National Notifiable Disease Surveillance System (NNDSS) received 982 tuberculosis (TB) notifications in 2003, of which 947 were new cases, 33 were relapses and two were cases with unknown history. The incidence of TB in Australia has remained at a stable rate since 1985 and was 4.9 cases per 100,000 population in 2003. The high-incidence groups remain people born overseas and Indigenous Australians at 19.9 and 8.7 cases per 100,000 population, respectively. By contrast the incidence in non-Indigenous Australians was 0.9 per 100,000. Comparison of the 2003 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups.  相似文献   
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BACKGROUND: The current tumor-node-metastasis system is inadequate to accurately classify patients in terms of prognosis. Thus, with the availability of recently developed molecular tools, considerable interest lies in discovering prognostic markers in order to guide treatment decisions. In this study, we sought to determine the prognostic significance of the cell cycle regulator cyclin D1 in oropharyngeal squamous cell carcinoma (OSCC). EXPERIMENTAL DESIGN: We studied the protein expression levels of cyclin D1 on a tissue microarray composed of 63 OSCCs with long-term follow-up data available. Protein expression was analyzed with an automated in situ quantitative (AQUA) method which allows preservation of tissue morphology while quantifying protein expression in paraffin-embedded tissue. RESULTS: The mean follow-up time was 35 months. High cyclin D1 nuclear expression was associated with increased 5-year local recurrence rate (48% versus 15%), inferior 5-year disease-free survival (16% versus 58%), and inferior 5-year overall survival (17% versus 53%). In multivariate Cox regression, high nuclear cyclin D1 expression was an independent predictor for local recurrence, disease-free survival, and overall survival at 5 years. CONCLUSIONS: Our results indicate that quantitative assessment of nuclear cyclin D1 expression level by automated in situ quantitative analysis is a strong predictor for outcome in OSCC. Thus, cyclin D1 may be a potential target for molecular intervention in patients with oropharyngeal squamous cell cancer.  相似文献   
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