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Background: Central venous access systems are frequently used for delivery of medications; however, few studies have compared surgical and postoperative complications of right versus left access via the subclavian vein (SCV). The aim of this study was to compare the surgical and postoperative complications associated with Port-A-Cath system insertion via the right and left SCV. Methods: The medical records of patients who received Port-A-Cath insertion via the SCV for parenteral chemotherapy between August 2004 and July 2008 were reviewed. The incidence of surgical and postoperative complications was compared between patients who received right- versus left-SCV Port-A-Cath insertion. Results: A total of 1,848 patients were included in the study. Right-SCV catheterization was attempted in 1,029 (55.7%) patients and was successful in 866 (84.2%). Left-SCV catheterization was attempted in 819 (44.3%) patients and was successful in 651 (79.5%). The mean length of postoperative follow-up was 417.3 ± 401.3 and 396.7 ± 379.9 days for the right- and left-SCV groups, respectively. The incidence of SCV puncture failure was significantly lower in the right-SCV group (12.3%) compared with the left-SCV group (16.8%, p = 0.006). The incidence of catheter knotting at the ipsilateral brachiocephalic vein was also significantly lower in the right-SCV group (0.0%) compared with the left-SCV group (0.5%, p = 0.038), as was the incidence of catheter occlusion (1.0% for right SCV vs. 3.5% for left SCV, p = 0.001). Conclusion: These findings suggest that the right-SCV approach is superior to the left-SCV approach for Port-A-Cath insertion.  相似文献   
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This study examines the relative importance of fitness versus fatness in predicting mortality in elderly populations aged 70 years and over, and whether fitness may account for the ‘paradoxical’ relationship between better survival and increasing weight. Four thousand community-living Chinese men and women aged 65 years or over were recruited and stratified so that approximately 33% were in each of the age groups: 65–69, 70–74, and 75 or above. Medical history, height, weight, waist–hip ratio, body composition using DEXA, and walking speed were obtained. They were followed up for a mean of 7.0 years to ascertain death. Compared with the high fitness category, those in the moderate and low categories have a 43% and 68% increased risk of mortality at 7 years adjusting for multiple confounders. When mortality risk according to various fatness indicators was examined, only the lowest quartile of BMI, BFI, and FLMR conferred statistically significant increased risk. Fitness categories were significantly associated with all fatness indicators. The finding of fewer people in the high fitness category among the highest quartiles of other fatness indicators suggests that fitness is not the underlying mechanism for the obesity paradox. Within each quartile of fatness indicator, there was a significant trend towards reduced mortality with increasing fitness. In conclusion, the study confirms the beneficial effects of cardiorespiratory fitness on mortality but does not explain the ‘obesity paradox’. The findings underscore the importance of maintaining physical fitness through exercise and re-confirm the importance of weight maintenance in reducing mortality risk.  相似文献   
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Epstein-Barr virus(EBV)-associated gastric carcinoma(EBVaGC)comprises nearly 10%of gastric carcinoma cases worldwide.Recently,it was recognised to have unique clinicopathologic characteristics,including male predominance,lower rates of lymph node involvement,and better prognosis.EBVaGC is further characterised by abnormal hypermethylation of tumour suppressor gene promoter regions,causing down-regulation of their expression.In the present review,we critically discuss the role of EBV in gastric carcinogenesis,summarising the role of viral proteins and microRNAs with respect to aberrant methylation in EBVaGC.Given the role of epigenetic dysregulation in tumourigenesis,epigenetic modifiers may represent a novel therapeutic strategy.  相似文献   
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Advances in Health Sciences Education - Recently, due to scarce resources and the need to provide an evidence-base for healthcare professions’ education (HPE), HPE research centres...  相似文献   
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In aging humans and rodents, inter-individual differences in cognitive function have been ascribed to variations in long-term glucocorticoid exposure. 11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) regenerates the active glucocorticoid cortisol from circulating inert cortisone, thus amplifying intracellular glucocorticoid levels in some tissues. We show that 11beta-HSD1, but not 11beta-HSD2, mRNA is expressed in the human hippocampus, frontal cortex, and cerebellum. In two randomized, double-blind, placebo-controlled crossover studies, administration of the 11beta-HSD inhibitor carbenoxolone (100 mg three times per day) improved verbal fluency (P < 0.01) after 4 weeks in 10 healthy elderly men (aged 55-75 y) and improved verbal memory (P < 0.01) after 6 weeks in 12 patients with type 2 diabetes (52-70 y). Although carbenoxolone has been reported to enhance hepatic insulin sensitivity in short-term studies, there were no changes in glycemic control or serum lipid profile, nor was plasma cortisol altered. 11beta-HSD1 inhibition may be a new approach to prevent/ameliorate cognitive decline.  相似文献   
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