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71.
We investigated role of reactive oxygen species (ROS) and apoptosis in the pathogenesis of infertility in experimental model of varicocele. The protective effect of vitamin E was also examined. Three groups of rats were constructed as the first group had sham operation, experimental varicoceles were established by partial ligation of the left renal vein in later two groups. Third group had received vitamin E. Production of ROS was determined by chemiluminescence assay (CL). The in situ end labelling technique was utilized to investigate apoptosis. Tissue vitamin E levels were measured by high performance liquid chromatography. The differences between luminol enhanced CL levels of groups were not statistically significant. However, the difference between CL levels of lucigenin probe in left testicles of sham and varicocele groups were statistically significant ( p = 0.0007). Similarly, the results of the third group receiving vitamin E significantly differed from the varicocele group ( p = 0.0025). The difference of apoptotic index was also statistically significant between sham and varicocele groups ( p = 0.0038). Although the values of apoptotic index detected in the vitamin E group were lower compared with the varicocele group, the difference was not significant. This study proposes that ROS production and apoptosis in the testicles were induced with experimental varicocele. Vitamin E had a protective role. An increased rate of apoptosis with experimental varicocele suggests a molecular alteration, which may involve ROS overproduction as the triggering mechanism. Consequently, this study indicates an association between varicocele and infertility at molecular level through stimulation of ROS and apoptosis.  相似文献   
72.
Inflammatory and prothrombotic markers are elevated in individuals with mild to moderate renal disease. It was hypothesized that these markers may also be determinants of the progression of renal disease. The association of six markers-serum C-reactive protein (CRP), white blood cell (WBC) count, fibrinogen, factor VII, albumin, and hemoglobin-with subsequent elevations of creatinine and decline in estimated GFR in the Cardiovascular Health Study, a community-based cohort of elderly individuals, was analyzed. Linear regression was used to determine predictors of an annualized change in serum creatinine as the main outcome. Duration of follow-up was 7 yr for the original cohort and 4 yr for the more recently recruited black cohort. A total of 588 (12.7%) individuals had a decline in estimated GFR of at least 3 ml/min per yr per 1.73 m(2). Higher CRP (P < 0.001), WBC count (P < 0.001), fibrinogen (P < 0.001), and factor VII (P < 0.001) levels and lower albumin (P < 0.001) and hemoglobin levels (P < 0.001) were associated with a rise in creatinine, after adjusting for age. With additional adjustments for race, gender, baseline creatinine, systolic and diastolic BP, lipid levels, weight, and pack-years smoking, higher CRP, factor VII, fibrinogen, WBC count, and lower albumin and hemoglobin levels remained associated with a rise in creatinine. Similar results were found for decline in estimated GFR. The decline in GFR was greater with increasing number of inflammatory or prothrombotic markers that were above the median (below for hemoglobin and albumin). Inflammatory and prothrombotic markers are predictors for a change in kidney function in elderly individuals. Interventions that reduce inflammation might confer significant cardiovascular and renal benefits.  相似文献   
73.
74.
This paper compares willingness to pay (WTP) estimates generated from the dichotomous choice (DC) and payment card (PC) approaches. In a split-sample WTP experiment concerned with allocating scarce health care resources across three health care interventions, the DC approach is shown consistently to generate larger welfare estimates than the PC. Observed difference between PC and DC experiments cannot be explained by the inclusion of non-demanders or methods of statistical analysis but may be partly explained by "yea-saying". No evidence of range bias or mid-point bias was found with PC responses. Data were also collected on respondents' ordinal rankings of the three interventions and person-trade-offs (PTOs). Neither of these approaches converged with WTP. Future work must address the decision heuristics individuals employ when responding to valuation experiments.  相似文献   
75.
Yavuz O  Cam M  Bukan N  Guven A  Silan F 《Acta histochemica》2003,105(3):261-266
The aim of the present study was the evaluation of possible protective effects of melatonin against beta-cell damage in streptozotocin-induced diabetes in rats. Malondialdehyde levels and glutathione peroxidase activity were measured in pancreatic homogenates. Pancreatic beta-cells were examined by immunohistochemical methods. Streptozotocin was injected intraperitoneally at a single dose of 60 mg/kg for induction of diabetes. Melatonin (200 microg/kg/day, ip) was injected for 3 days prior to administration of streptozotocin; these injections were continued until the end of the study (4 weeks). Streptozotocin induced a significant increase in malondialdehyde levels (p < 0.01) and a significant decrease in glutathione peroxidase activity (p < 0.05) in pancreatic tissue. Degeneration of islet cells and weak immunohistochemical staining of insulin was observed in diabetic rats. Treatment of diabetic rats with melatonin markedly reduced malondialdehyde production (p < 0.05) and increased glutathione peroxidase activity (p < 0.01) without affecting hyperglycemia. Increased staining of insulin and preservation of islet cells were apparent in the melatonin-treated diabetic rats. These data suggest that melatonin treatment has a therapeutic effect in diabetes by reduction of oxidative stress and preservation of pancreatic beta-cell integrity.  相似文献   
76.
Treatment of chronic atrial fibrillation with intraoperative radiofrequency ablation is gaining more acceptance in patients with rheumatic valve disease. This article reports a case of fatal atrio-esophageal fistula after radiofrequency ablation in a patient with rheumatic mitral and aortic valve disease with chronic atrial fibrillation.  相似文献   
77.
As resources in health care are scarce, health authorities and other health organizations are charged with determining how best to spend limited resources. While a number of formal approaches to priority setting within health authorities have been used internationally, there has been limited success with such activity, particularly across major service portfolios. This participatory action research project instituted a novel priority setting framework, coined macro-marginal analysis (MMA), in a fully integrated urban health region in Alberta, Canada. The focus of MMA is on identifying areas for service growth and areas for resource release, then determining, based on pre-defined, locally generated criteria, if actual shifts or re-allocation of resources should occur. For fiscal year 2002/03, the Calgary Health Region identified over 40 M dollars in resource releases (approximately 3% of the total budget), which were made available for servicing the deficit, and more importantly for our purposes, re-investing in service growth areas. The MMA framework is pragmatic in nature and has the ability to incorporate relevant evidence directly into the decision-making process. This work constitutes a significant advancement in health economics, and responds where previous priority setting approaches have failed in that it allows decision-makers to achieve genuine re-allocation of resources with the aim of improving population health or better meeting other important criteria.  相似文献   
78.
OBJECTIVES: This study compared trends in the incidence of work-related morbidity and disability across 3 sources of surveillance data in a Canadian province. METHODS: Time series estimates of workplace injuries and work-related disability based on 2 panel surveys in the province of Ontario, Canada, for the period 1993-1998 were compared with rates of work-related injury and illness compensation claims during the same period. RESULTS: Lost-time compensation claims declined by 28.8% over this 6-year period. The incidence of self-reported work-related injury declined by 28.2%, and the self-reported incidence of work absence for work-related causes declined by 32.2%. CONCLUSIONS: Parallel reductions in work-related morbidity were seen in 3 independent data sources. These results support an interpretation that there has been an important reduction in injury risk in Ontario workplaces over the past decade.  相似文献   
79.
The burnout in nursing academicians in Turkey   总被引:7,自引:0,他引:7  
The purpose of this study was to determine the level of burnout in nursing academicians in Turkey and to investigate the variables which are strongly correlated with the burnout nursing education settings in Turkey. The sample of the study consisted of the nursing academicians working in the schools of nursing at the different universities in Turkey. Although the total number of nursing academicians in Turkey was 179, the subjects who agreed to participate in the research was 135. The Maslach Burnout Inventory (MBI) was used to measure burnout, after having been statistically tested for its validity and reliability in nursing education settings in Turkey. The multiple regression analysis was carried out in order to determine the main variables correlated with burnout, namely "the predictors" of each of the three components (emotional exhaustion (EE), depersonalization (DP), personal accomplishment (PA)) of burnout. The results indicated that the most significant predictor of EE was work-setting satisfaction, of DP was job pressure, and of PA was job satisfaction in nursing education settings in Turkey. Finally, these findings were compared with of those previous studies in the field.  相似文献   
80.
BACKGROUND: Individuals' valuation of changes in health states in monetary terms have been measured by examining changes in the direct and indirect costs of disease and by the willingness-to-pay (WTP) methodology. METHODS: In 2002, a 2-part study was conducted in Quebec. In one part of the study, 121 rheumatoid arthritis (RA) patients from the McGill University Health Centre were mailed the Stanford Cost Assessment Questionnaire, which enabled the elicitation of direct costs and indirect costs, according to the friction cost and the human capital methods. The other part was a phone survey conducted in a representative sample of the general population and in the same sample of patients, aiming to elicit the societal WTP for a complete cure of RA in the context of 2 different scenarios: a public coverage or private insurance. These estimates were then compared. RESULTS: Estimates of the cost of illness of RA ranged from 11,717 to 28,498 Canadian Dollars (CAD) depending on the method. These estimates are higher than those previously published in Canada from the 1990s, which is partly due to the recent and costly biological therapies and to a change in the measurement of productivity losses. These estimates are somewhat lower than the societal WTP elicited from the WTP survey, that is, 26,717 and 36,817 CAD per RA case, depending on the public or private health insurance context in which the cure would be available. CONCLUSION: Given that neither method is ideal, data from both methods would provide an important sensitivity analysis when monetary estimates of health state changes are required.  相似文献   
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