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BACKGROUND: Reactive nitrogen species, formed via the reaction of nitric oxide (NO) with superoxide anion and via (myelo)peroxidase-dependent oxidation of NO(2)(-), have potent proinflammatory and oxidizing actions. Reactive nitrogen species formation and nitrosative stress are potentially involved in chronic obstructive pulmonary disease (COPD) pathogenesis. OBJECTIVES: To investigate the expression of markers of nitrosative stress, including nitrotyrosine (NT), inducible NO synthase (iNOS), endothelial NO synthase (eNOS), myeloperoxidase (MPO), and xanthine oxidase (XO) in bronchial biopsies and bronchoalveolar lavage from patients with mild to severe stable COPD compared with control groups (smokers with normal lung function and nonsmokers). METHODS: The expression of NT, iNOS, eNOS, MPO and XO in the bronchial mucosa and bronchoalveolar lavage of patients was measured by using immunohistochemistry, Western blotting, and ELISA and correlated with the inflammatory cell profile. RESULTS: Patients with severe COPD in stable phase had higher numbers of NT(+) and MPO(+) cells in their bronchial submucosa compared with mild/moderate COPD, smokers with normal lung function, and nonsmokers (P < .01). iNOS(+) and eNOS(+) but not XO(+) cells were significantly increased in smokers with COPD or normal lung function compared with nonsmokers (P < .05 and P < .01, respectively). In patients with COPD, the number of MPO(+) cells was significantly correlated with the number of neutrophils (r = +0.61; P < .0025) in the bronchial submucosa. Furthermore, the number of NT(+) and MPO(+) cells was negatively correlated with postbronchodilator FEV(1). CONCLUSION: These data suggest that nitrosative stress, mainly mediated by MPO and neutrophilic inflammation, may contribute to the pathogenesis of severe COPD.  相似文献   
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IntroductionMetabolic syndrome (MS) is a major health problem, and has economic effects on enterprises. The workplace is thus an important environment for primary prevention of risk factors for cardiovascular disease.ObjectiveTo determine the prevalence of MS and variables related to its development in hospital workers.MethodsWe performed a cross-sectional study of 740 workers in a large university hospital. Socioeconomic variables, anthropometric and blood pressure measurements, and laboratory exams were analyzed. MS was defined according to the criteria of the International Diabetes Federation.ResultsOf the 740 workers, 72.4% were female and mean age was 34.9±9.5 years; 27.8% worked the morning shift, 20.3% the afternoon shift, 34.1% office hours, and 17.8% the night shift. As to educational level, 86.6% had finished high school or college. Waist circumference was high in 55.4%. Overall MS prevalence was 12.8%, 16.2% in males and 11.6% in females. Logistic regression analysis showed an independent association between MS and the following variables: elementary education, period of employment >10 years, office hours shift, and age group.ConclusionA diagnosis of MS was affected by age, educational level, work shift, and prolonged period of employment. Hospital workers do not differ from other populations and also need stimuli to make preventive changes to their behavior to modify cardiovascular risk factors.  相似文献   
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Background: Recently the new specific phosphodiesterase-5 inhibitor sildenafil was introduced into therapy for erectile dysfunction. The hemodynamic effects of sildenafil may be potentially hazardous for patients with cardiac disease. Sildenafil has been reported to augment the hypotensive effects of nitrates. There is sparse information regarding the systemic and pulmonary hemodynamic effects of a single oral dose of sildenafil in patients with stable angina. Methods: Male patients referred for coronary angiography with diagnosis of chronic stable angina were enrolled in this study to assess the acute hemodynamic effects of sildenafil. Patients receiving long-acting or sublingual nitrates for the last 6 h before the study were excluded. Hemodynamic measurement were taken during right and left heart catheterization in the basal state and 60 min after 50 mg of oral sildenafil. Results: Twelve patients (age 53±7 years) were studied. All had stable angina CCS class II or III. Four had previous myocardial infarction. By coronary angiography, seven patients had at least one coronary artery with >70% stenosis, four had at least one with 50–70% stenosis, and one had only intimal irregularities. There were no significant effects of sildenafil on systemic or pulmonary arterial pressure, left ventricle endiastolic pressure, cardiac output, and systemic or pulmonary vascular resistance (P>0.05 for all). No adverse events were observed. Conclusion: A single oral dose of sildenafil had no significant hemodynamic effect in supine patients with stable angina. Isolated administration of sildenafil does not appear to be associated to adverse cardiovascular effects.  相似文献   
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Bibliometry is a quantitative statistical technique to measure levels of production and dissemination of knowledge, as well as a useful tool to track the development of an scientific area. The valuation of production required for recognition of researchers and magazines is accomplished through tools called bibliometricindexes, divided into quality indicators and scientific impact. Initially developed for monographs of statistical measures especially in libraries, today bibliometrics is mainly used to evaluate productivity of authors and citation repercussion. However, these tools have limitations and sometimes provoke controversies about indiscriminate application, leading to the development of newer indexes. It is important to know the most common search indexes and use it properly even acknowledging its limitations as it has a direct impact in their daily practice, reputation and funds achievement.  相似文献   
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