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Clinical Oral Investigations - This overview analyzed the quality of the systematic reviews (SRs) available on treatments for molar-incisor hypomineralization (MIH). Six electronic databases were...  相似文献   
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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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Objective: Analyze the hypothesis that swimming exercise, in rats suckled under distinct litter sizes, alters behavioral parameters suggestive of anxiety and recognition memory, and the electrocorticogram potentiation that occurs after the excitability-related phenomenon that is known as cortical spreading depression (CSD).

Methods: Male Wistar rats were suckled in litters with six or 12 pups (L6 and L12 groups). Animals swam at postnatal days (P) 8–23, or P60–P75 (early-exercised or late-exercised groups, respectively), or remained no-exercised. Behavioral tests (open field – OF and object recognition – OR) were conducted between P77 and P80. Between P90 and P120, ECoG was recorded for 2 hours. After this ‘baseline’ recording, CSD was elicited every 30 minutes over the course of 2 hours.

Results: Early swimming enhanced the number of entries and the percentage of time in the OF-center (P?<?0.05). In animals that swam later, this effect occurred in the L6 group only. Compared to the corresponding sedentary groups, OR-test showed a better memory in the L6 early exercised rats, and a worse memory in all other groups (P?<?0.05). In comparison to baseline values, ECoG amplitudes after CSD increased 14–43% for all groups (P?<?0.05). In the L6 condition, early swimming and late swimming, respectively, reduced and enhanced the magnitude of the post-CSD ECoG potentiation in comparison with the corresponding L6 no-exercised groups (P?<?0.05).

Discussion: Our data suggest a differential effect of early- and late-exercise on the behavioral and electrophysiological parameters, suggesting an interaction between the age of exercise and the nutritional status during lactation.  相似文献   

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