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Asthma and rhinitis epidemiology has wide variations around the world. The aim of this review was verify the prevalence of asthma and rhinitis in South America and report differences from other regions of the world. We reviewed studies with International Study of Asthma and Allergies in Childhood (ISAAC) methodology in South America, Phases I and III. In South America the ISAAC Phase I ranked four countries among top ten in prevalence of asthma and three countries among top ten in prevalence of rhinoconjunctivitis. ISAAC Phase III showed little changes in asthma and rhinitis prevalence in South American countries. The prevalence increases of asthma and rhinitis in South American centers indicate that the burden of both is continuing to rise, but the differences in prevalence are lessening.  相似文献   
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Background: Few electrocardiographic parameters beyond the QRS duration were studied with regard to the correlation with mechanical dyssynchrony. This study aims to analyze the correlation between electrocardiographic parameters and mechanical dyssynchrony in patients with symptomatic heart failure (HF) and left bundle branch block (LBBB). Methods: Patients with HF, ejection fraction ≤ 35%, and QRS interval ≥ 120 ms with a LBBB were prospectively studied. We analyzed the correlation between electrocardiographic parameters (QRS duration, R voltage in limb leads, S voltage in precordial leads, Sokolow and Cornell indexes, QRS axis deviation, and QRS notches in lateral and inferior leads) and mechanical dyssynchrony measured by tissue Doppler imaging (TDI). Results: A group of 50 patients were studied, 60% male, 78% with nonischemic cardiomyopathy, NYHA Class III–IV (86%), and ejection fraction of 0.22 ± 0.6. Intra‐ and interventricular dyssynchrony occurred in 68% and 74% of patients, respectively. The S amplitude in precordial leads and the Sokolow and Cornel indexes show a weak correlation with the degree of dyssynchrony. In the patients with QRS notching in the lateral and inferior leads, we observed significantly greater prevalence of intraventricular dyssynchrony, with sensitivity and specificity of 85% and 56%, respectively, for notches in lateral leads. The QRS duration presents moderate correlation with the degree of both intraventricular (r = 0.48) and interventricular dyssynchrony (r = 0.46). Conclusion: The following electrocardiographic parameters were related to the degree of mechanical dyssynchrony: QRS duration and notches in QRS. In addition, the patients tend to have highest S amplitude in precordial leads. Ann Noninvasive Electrocardiol 2011;16(1):41–48  相似文献   
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The nanotechnology has revolutionized the global market with silver nanoparticles (AgNP) occupying a prominent position due to their remarkable anti-bacterial properties. However, there is no data about the adverse and toxic effects of associations of AgNP and ubiquitous compounds, such as polycyclic aromatic hydrocarbons (PAH). In the current study, we investigated the responses of HepG2 cells to realistic concentrations of AgNP (0.09, 0.9, and 9?ng ml?1) and mixture of PAH (30 and 300?ng ml?1), separately and in association. Cell viability and cytotoxicity (neutral red retention and MTT production assays) and proliferation (crystal violet [CV] assay), xenobiotic efflux transporter activity (rhodamine B accumulation assay), ROS levels (dichlorodihydrofluorescein diacetate assay), and lipid peroxidation (pyrenylphosphine-1-diphenyl assay) were analyzed. There was no decreases of cell viability after exposure to AgNP, PAH and most of AgNP?+?PAH associations, but increases of cell viability/number (CV assay) occurred. Efflux transporter activity was not affected, with exception of one AgNP?+?PAH associations, ROS levels increased, but lipid peroxidation decreased. Some toxicological interactions occurred, particularly for the highest concentrations of AgNP and PAH, but there is no evidence that these interactions increased the toxicity of AgNP and PAH.  相似文献   
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The most common temporomandibular disorders (TMD) signs and symptoms are related to muscle sensitivity through palpation, restricted mouth opening, asymmetric mandibular movements, joint sounds, pain and otologic signs and symptoms. To date, counselling, occlusal splints, exercises, biofeedback and acupuncture are examples of conservative modalities proposed for TMD therapy. The aim of this systematic review was to investigate the effect of these conservative therapies for TMD on otologic signs and symptoms. The authors searched the following electronic databases published up to 1st May 2015: PubMed, LILACS, Scopus, Web of Science and Science Direct with no time or language limitations. Using a two‐phase selection process, the authors identified 08 articles and used them to conduct a qualitative analysis. Methodological quality of each article was performed with the aid of ‘Quality Assessment of a Cohort Study’ and ‘Quality Assessment of a Randomized Clinical Trial’, developed by the Dutch Cochrane Centre, a centre of the Cochrane Collaboration. This systematic review showed in seven of the eight studies included that a total or partial resolution of otologic complains occurred after counselling, exercise therapies and occlusal splint therapy. Upon the limitations of the studies included in this systematic review, the present outcomes suggested that there is insufficient evidence in favour or against the conservative therapies for TMD on changes in otologic signs and symptoms. Thus, further studies with a higher level of evidence and more representative samples should be conducted to better understand the relationship of TMD therapy changes on otologic complains.  相似文献   
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Objective  

To evaluate the effectiveness and safety of polyunsaturated fatty acids for the treatment of the premenstrual syndrome (PMS) using a graded symptom scale and to assess the effect of this treatment on basal plasma levels of prolactin and total cholesterol.  相似文献   
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