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Objective:The present study evaluates a training program for fitting different hearing protection devices (HPDs) based on personal attenuation rating (PAR) before, immediately after, and six months after training.Methods:A total of 67 workers from a public university in the city of São Paulo, Brazil, were invited to participate in the measurement of PARs for foam and silicone protectors through the 3M™ E-A-Rfit Validation System. Two evaluations were performed for each protector at each sampling date: one after reading printed material (the package instructions) and another after being trained by an audiologist. The same procedures were repeated after six months. The final sample consisted of 30 individuals. ANOVA was used for statistical analysis.Results:Larger PAR values were observed after training by the audiologist, and smaller values were observed after six months. Then, after re-training, the values increased again. There were no statistically significant differences in PAR among the HPDs tested. Even after the two training sessions, 23 to 27% of the subjects did not obtain adequate PAR values.Conclusion:These findings emphasize the need for continual worker training in the correct fit of earplug HPDs and the importance of longitudinal PAR monitoring. In addition, some workers, despite the training provided, did not adapt to the HPDs used. Therefore, it is essential that other protection methods and/or other HPD types are made available to these individuals.Key words: Hearing, noise-induced hearing loss, occupational health, personal protective equipment, hearing protection devices  相似文献   
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Journal of Digital Imaging - Vertebral Compression Fracture (VCF) occurs when the vertebral body partially collapses under the action of compressive forces. Non-traumatic VCFs can be secondary to...  相似文献   
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Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals.  相似文献   
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The aetiology of vitiligo has not been fully elucidated, and several hypotheses have been investigated; among them, the most explored assumes an autoimmune basis for the disease. Supporting this hypothesis is the frequent co-occurrence of autoimmune diseases with vitiligo. In addition, various genetic loci associated with vitiligo harbour key immune response genes. Our general hypothesis is that autoimmunity-associated genes participate in the control of vitiligo susceptibility. To investigate this hypothesis, we tested for association between vitiligo and genes CYP27B1, REL, TNFAIP3 and IL2/IL21, all previously related to autoimmune diseases associated with vitiligo. The study was performed using two independent population samples: a family-based discovery set (211 trios) and a replication set (131 cases/119 controls). Statistically significant association with vitiligo was detected between markers of the REL and IL2 gene in the family-based sample. Both association signals were concentrated among patients displaying autoimmune comorbidity and non-segmental vitiligo. Evidence for validation was detected for IL2 marker. Our findings suggest REL and IL2 as new vitiligo susceptibility genes and reinforce the hypothesis of a shared genetic mechanism controlling vitiligo and other autoimmune diseases.  相似文献   
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This case report demonstrates how extracting a maxillary deciduous canine affects the eruption path of a labially displaced ectopically erupting permanent canine. A long-term follow-up is presented, and the biologic mechanisms are discussed.  相似文献   
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BACKGROUND: High rates of morbidity and mortality are observed in patients with advanced heart failure (AHF). AHF is now considered the most costly syndrome in cardiology owing to the substantial economic burden associated with hospitalizations for acute decompensation. A management program that involves specialized follow-up by a multidisciplinary team has been suggested as a desirable strategy for improving outcomes for these patients. ObjectivE: To evaluate the impact of a specialized outpatient heart failure (HF) follow-up program for patients with AHF on frequency and duration of hospitalization for HF and functional status. METHODS: We retrospectively studied 167 consecutive patients with AHF who were referred to the outpatient HF follow-up program in our institution between January and November 2002, of whom 147 followed for > or =30 days were included in the analysis. In addition to demographic and baseline clinical characteristics, HF medication and NYHA functional class, the number and duration of hospitalizations for HF during the previous 12 months were recorded and compared at the time of referral and after a follow-up period of 6.5+/-3 months. RESULTS: Of the 147 patients analyzed (aged 60.8+/-13 years; 79% male; left ventricular ejection fraction 27+/-11%), 67% were in NYHA functional class III, 20% in class II and 13% in class IV at the time of referral. There was a significant improvement in functional class during the mean follow-up period: 55% of the patients were in class III, 37% in class II, 5% in class I and 3% in class IV (p<0.0001). The proportion of patients on beta-blockers or spironolactone increased from 33% and 51% at the time of referral to 69% and 71% respectively after referral (p<0.0001). In the 12 months before referral, 39% of the patients had been hospitalized for acute decompensation of HF (87 hospitalizations - mean 7.2/month) versus 13% of the patients during the mean follow-up period (25 hospitalizations - 3.8/month, p<0.0001). No significant differences were found in the proportion of patients on angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, digoxin or diuretics, or in the mean duration of hospitalization before and after referral. ConclusioN: The specialized follow-up of patients with AHF by a team with expertise in HF resulted in significant therapeutic optimization. Increased use of beta-blockers and spironolactone was associated with significant improvement in functional capacity and significant reduction in hospitalizations.  相似文献   
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