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OBJECTIVE: To conduct a systematic review to gather the available evidence on the optimum timing of the radiotherapy in relation to autologous breast reconstruction. MATERIAL AND METHODS: The data was extracted from scientific databases, and a manual follow-up of references. The studies were selected which included at least 20 patients with any method of autologous breast reconstruction who were treated with adjuvant radiotherapy either before or after their reconstruction, and had addressed the effects of radiotherapy on the cosmetic outcome in their results. The principal outcome was cosmetic appearance. Secondary outcomes were immediate and delayed complications. RESULTS: We could not find any randomised controlled trial on this topic. Ten studies were included, most were retrospective, heterogeneous in terms of control groups, radiation doses, follow-up duration, and outcome measurements. Two studies included no control groups, and four studies compared the outcomes of patients with radiotherapy either before (n=3) or after (n=1) autologous breast reconstruction. The overall incidence of complications was increased in patients with radiotherapy in three out of these four studies. Only four studies directly compared the outcomes of patients who received radiotherapy before with patients who received radiotherapy after autologous breast reconstruction and two out of these reported worse outcomes associated with post-reconstruction radiotherapy. CONCLUSIONS: Despite the paucity of the published data, the current evidence suggests that the radiation has a deleterious effect on autologous flap reconstruction. Until better methods of radiation delivery can be devised to minimise the long term radiation sequelae in the irradiated tissue, delayed reconstruction seems to be a safe option in most of the cases. However, the findings from these studies should be interpreted with great caution before generalising from their results.  相似文献   
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Parkinson's disease (PD) occurs worldwide, but little is known about PD in Africa. We systematically reviewed publications on PD in Africa, with emphasis on epidemiologic and genetic studies. Articles published between 1944 and December 2004 were identified using several strategies. The studies emanated from 13 African countries (Kenya, Uganda, Tanzania, Ethiopia, Nigeria, Senegal, Ghana, Togo, Libya, Tunisia, Algeria, Zimbabwe, and South Africa). The publications fell into four categories: clinical series (n = 17), prevalence studies (n = 7), incidence studies (n = 1), and genetic studies (n = 3). The clinical series documented the occurrence of PD in Africa and described its clinical characteristics. The prevalence studies suggested some intracontinental geographic variation in PD prevalence. Overall, the prevalence figures and the incidence rates of PD in Africa appeared lower than those reported for European and North American populations. Few genetic studies of PD have been reported from Africa, and none in blacks. There are no case-control or cohort studies of PD reported from Africa. This review provides a summary of PD research in Africa over the past 60 years and highlights the information gaps and potential areas for future research.  相似文献   
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The α7 subtype of the nicotinic acetylcholine receptor (α7 nAChR) is prominently expressed in the hippocampus where it is thought to play a role in the regulation of cognitive function. In this study, we have investigated the effects of 5-hydroxyindole (5-HI), a positive modulator of the α7 nAChR, on GABAergic activity in hippocampal CA1 stratum radiatum interneurons in acute rat brain slices. Superfusion of 5-HI (100 μ m ) increased the mean frequency and amplitude of spontaneous IPSCs (sIPSCs). The potentiation was occluded by pretreatment of slices with: (1) a high concentration of the broad-spectrum agonist nicotine to desensitize the α7 receptor, (2) an α7 nAChR antagonist, and (3) tetrodotoxin to block action potential firing. These results indicate that facilitation by 5-HI was mediated by the α7 nAChR and required neuronal excitation. In contrast, 5-HI had no effect on sIPSCs recorded in hippocampal slices from younger animals, even though the expression of functional α7 nAChRs was confirmed by agonist application experiments. In these slices, 5-HI only enhanced sIPSCs after pretreatment with the acetylcholinesterase inhibitor Bw284c51. Taken together, our results suggest that 5-HI facilitates GABAergic transmission via excitation of the α7 nAChR, and that this effect requires the presence of the endogenous agonist ACh in the extracellular environment of the receptor.  相似文献   
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This study was undertaken to examine the beliefs and practices of dietitians in relation to cancer risk reduction through nutrition. Respondents to the national survey (N=384, 70 percent) were similar in demographic, educational, and professional characteristics to the American Dietetic Association census data. They reported a strong preventive health orientation: mean performance on 10 preventive health behaviors was 77.5 on a 100 point scale. Half (53 percent) believed cancer would be serious if they developed it, 47 percent believed it was not likely that they would. About 20 percent of the respondents felt that the role of nutrition in cancer etiology was unclear. Dietitians believed strong research support existed for increasing whole grains, fruits and vegetables, and fiber to reduce cancer risk but that little evidence supported use of dietary supplements. Dietitians regularly practiced 75 percent of nutrition recommendations they believed to be effective in reducing cancer risk. Beliefs about the effectiveness of a recommendation accounted for the largest percentage of variance on nutritional practices. While dietitians reported many preventive health practices, including following nutrition recommendations, they seemed to be doing so for reasons other than preventing cancer.Nancie S. Merlino is Assistant Professor, Nutrition and Food Science, Wayne State University, Detroit, MI 48202 and James H. Price, Professor of Health Promotion, Department of Health Promotion, University of Toledo, Toledo, OH 43606.Acknowledgement goes to Stephen Jurs, PhD; Fredrick Andres, PhD; and John Kish, PhD for assistance in design and analysis.  相似文献   
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