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21.
Occupational therapy is based on core values of altruism, equality, and honoring the dignity of others. Embedded in these values is the ever-present negotiation of power. To honor the concern for the welfare of others, researchers are challenged to think about issues of power throughout the research process. This paper identifies dilemmas and raises questions researchers might ask themselves as they struggle to share power in the interpretive research process.  相似文献   
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First noticed in Uganda in 1863 by a European explorer, sexually transmitted diseases (STDs) were cited as a major cause of morbidity and mortality throughout this century. In 1908 the venereal diseases campaign was launched marking the real introduction of western medicine. By the mid-1920s, the campaign was combined with the medical service but throughout the colonial period (1901-1962) venereal diseases were considered intractable. A 1991 survey revealed alarming incidence rates and in light of the importance of STDs as a co-factor in the transmission of HIV, it is of paramount importance to implement more effective control measures.  相似文献   
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Transforming growth factor beta is a polypeptide growth factor with a multiplicity of diverse biologic effects. Increasingly, data support a role for TGF beta in the autocrine regulation of normal epithelial cell growth (Figure 1). Definition of the normal pathways for growth stimulation and inhibition of epithelial cell growth by autocrine peptides like TGF beta and TGF alpha undoubtedly will increase understanding of normal growth and development, embryogenesis, wound repair, and tumorigenesis.  相似文献   
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The rat forebrain receives projections from both dorsal and median raphe nuclei. It has recently been shown that serotoninergic axons arising from the dorsal raphe nucleus, but not those from the median raphe nucleus, degenerate following systemic administration of p-chloroamphetamine (PCA). The present study was conducted to determine (i) whether the motor nucleus of the trigeminal nerve is innervated by overlapping projections from multiple serotonin cell groups and (ii) whether a particular subset of serotoninergic axon terminals in the trigeminal motor nucleus are sensitive to the neurotoxic effects of PCA. Retrograde transport was used in combination with immunofluorescence to identify the serotonin-positive cells that project to the trigeminal motor nucleus both in control rats and in rats previously treated with PCA. In untreated rats, an average of 95 retrogradely labeled serotonin-positive neurons were found in the dorsal raphe nucleus, 135 in the nucleus raphe obscurus, 132 in the nucleus raphe pallidus and 63 in the ventrolateral medulla. After treatment with PCA, there was a marked decrease (-77%) in the number of retrogradely labeled serotoninergic neurons in the dorsal raphe nucleus, whereas the number of labeled neurons was unchanged in the raphe obscurus and raphe pallidus. These results demonstrate that PCA selectively lesions serotonin axon terminals arising from the dorsal raphe nucleus, while sparing projections from the raphe obscurus and raphe pallidus to the trigeminal motor nucleus. This conclusion is in agreement with previous findings that in the forebrain only axons from the dorsal raphe are vulnerable to PCA. The data provide further evidence that serotoninergic axons originating in the dorsal raphe nucleus differ from other serotoninergic axons in their pharmacological properties and that the dorsal raphe may contain a functionally unique subset of serotonin neurons.  相似文献   
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BACKGROUND: Epidemiologic studies reveal that posttraumatic stress disorder (PTSD) is highly comorbid with both conduct disorder and major depression in men. The genetic and environmental etiology of this comorbidity has not been examined. METHODS: Data were analyzed from 6744 middle-aged male-male monozygotic and dizygotic twins from the Vietnam Era Twin Registry. Conduct disorder, major depression, and PTSD were assessed via telephone interview using the Diagnostic Interview Schedule for the DSM-III-R in 1992. Structural equation modeling was used to estimate additive genetic, shared environmental, and individual-specific environmental effects common and specific to conduct disorder, major depression, and PTSD. RESULTS: The association between conduct disorder and PTSD was explained primarily by common shared environmental influences; these explained 10% (95% confidence interval: 6%-17%) of the variance in PTSD. The association between major depression and PTSD was largely explained by common genetic influences; these explained 19% (95% confidence interval: 11%-26%) of the variance in PTSD. CONCLUSIONS: Our findings suggest that different etiologic mechanisms explain the association of conduct disorder and major depression with PTSD in male veterans. If replicated in other populations, results suggest research aimed at identifying specific genetic and environmental factors that influence PTSD may benefit from starting with those that have been more consistently and strongly associated with major depression and conduct disorder.  相似文献   
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The efficacy of total body showering and incision site scrub with disinfectant agents was evaluated in a randomized, prospective study of 575 patients undergoing selected surgical procedures. Patients who showered twice with 4% chlorhexidine gluconate had lower mean colony counts of skin bacteria at the surgical incision site in the operating room prior to the final scrub than patients who showered twice with povidone-iodine solution or medicated bar soap. Patients in the chlorhexidine group had no growth on 43% of the incision site skin cultures compared with 16% in the povidone-iodine group and 6% in the soap and water group. Patients who showered and who were scrubbed with chlorhexidine also had lower rates of intraoperative wound contamination. Bacteria were recovered from the wounds of 4% of patients using this regimen compared with 9% for patients who used povidone-iodine and 15% for patients who showered with medicated soap and water and were scrubbed with povidone-iodine. We noted no difference in surgery-specific infection rates among patients in the three treatment groups; however, our sample sizes were too small to evaluate this outcome parameter adequately. These data suggest that preoperative showering and scrubbing with chlorhexidine is an effective regimen to reduce extrinsic intraoperative contamination of the surgical wound from skin bacteria. The efficacy of this regimen to prevent postoperative wound infection needs to be evaluated in a well-designed, carefully controlled prospective trial with adequate numbers of patients to achieve statistically valid conclusions.  相似文献   
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