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Caio Henrique de Carvalho Assuno Júlio Csar Trabanco Raquel Fornaziero Gomes Renata Rodrigues Moreira Alessandra Giannella Samelli 《La Medicina del lavoro》2019,110(4):304
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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Laysa Toschi Martins Henrique Ravanhol Frigeri Caio Cesar Silva de Castro Marcelo Távora Mira 《Experimental dermatology》2020,29(6):535-538
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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Anja S Lindman Marit B Veier?d Jan I Pedersen Aage Tverdal Inger Nj?lstad Randi Selmer 《European journal of cardiovascular prevention and rehabilitation》2007,14(4):501-507
AIMS: To evaluate the predictive accuracy of the Systematic Coronary Risk Evaluation (SCORE) project high-risk function in Norway. METHODS AND RESULTS: We included 57 229 individuals screened in 1985-1992 from two population-based surveys in Norway (age groups 40-49, 50-59, and 60-69 years). The data have been linked to the Norwegian Cause of Death Registry. The SCORE high-risk algorithm for the prediction of 10-year cardiovascular disease (CVD) mortality was applied, and the risk factors entered into the model were age, sex, total cholesterol, systolic blood pressure, and smoking (yes/no). The number of expected events estimated by the SCORE model (E) was compared with the observed numbers (O). The SCORE low-risk algorithm was studied for comparison. In men, the observed number of CVD deaths was 718, compared with 1464 estimated by the SCORE high-risk function (O/E ratios 0.53, 0.53 and 0.45, for age groups 40-49, 50-59 and 60-69, respectively). In women, the observed and expected numbers were 226 and 547. The O/E ratios decreased with age (ratios 0.60, 0.45 and 0.37, respectively), i.e. the overestimation increased with age. The low-risk function predicted reasonably well for men (ratios 0.85, 0.92 and 0.79, respectively), whereas an overestimation was found for women aged 50-59 and 60-69 years (ratios 0.69 and 0.56, respectively). CONCLUSION: The SCORE high-risk model overestimated the number of CVD deaths in Norway. Before implementation in clinical practice, proper adjustments to national levels are required. 相似文献
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Paulo Cezar Galv?o do Amaral Euler de Medeiros ázaro Filho Thales Delmondes Galv?o Ettinger Eric Junior Galeno Egydio José de Magalh?es Neto Fabrício Mascarenhas Edvaldo Fahel 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(3):355-358
BACKGROUND: Randomized studies demonstrate that laparoscopic appendectomy yields better results compared with open techniques. We sought to identify factors that determine an extended hospital stay among patients undergoing laparoscopic appendectomy. METHODS: This was a prospective study including 669 patients undergoing laparoscopic appendectomy. We analyzed variables that can predict the length of hospital stay. RESULTS: Of 669 patients undergoing laparoscopic appendectomy, 141 stayed in the hospital for > or = 5 days (Group 1), and 97 stayed in the hospital for < or = 1 day after surgery (Group 2). The univariate analysis demonstrated that fever (P<0.0001), nausea and vomiting (P=0.060), leukocytosis (P<0.0001), gangrened or perforated intraoperative appearance of the appendix (P<0.0001), and appendix position behind the ileocecal junction (P<0.001) were related to a longer hospital stay. The multivariate analysis through logistical regression showed that the factors independently and significantly associated with an extended hospital stay were presurgical fever, appendix position behind the ileocecal junction, and intraoperative gangrened or perforated appearance of the appendix. CONCLUSION: Fever, appearance, and position of the appendix are factors related to an extended hospital stay. 相似文献
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Comparison of dynamic and step-and-shoot intensity-modulated radiation therapy planning and delivery. 总被引:1,自引:0,他引:1
Intensity-modulated radiation therapy (IMRT) is commonly delivered using the dynamic or segmental mode of multileaf collimators (DMLC or SMLC). Both methods are designed to deliver intensity-modulated beams as determined by inverse planning software. In this study, we have used the Helios IMRT planning system to generate ideal treatment plans for 10 cases of 2 common treatment sites (prostate and head and neck) and have investigated the actual treatment fluence distributions generated for each of the MLC leaf motion choices. The 2 dose delivery techniques were dosimetrically compared to each other and to the treatment plans. For each technique, point doses were measured in a water phantom using ionization chambers. Also for each technique, 2-dimensional dose distributions at a selected depth in a plastic phantom were obtained, using extended range film. The total delivery time and the number of monitor units (MU) delivered by each method were also compared. Our results indicate that the 2 delivery methods produce comparable results dosimetrically. For the cases reviewed, the delivery time was an average of 15% longer for SMLC deliveries, while the number of MUs (beam-on time) required by SMLC was an average of 15% fewer, than that for the DMLC. In the interest of simplicity, lower beam-on time, and potentially fewer mechanically-related problems, we think that the SMLC delivery technique may be the better choice when Helios is used for planning and Varian linear accelerators are used for delivery. 相似文献
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Robert A. Schnoll Ph.D. James Calvin B.A. Michael Malstrom B.S. Randi L. Rothman B.A. Hao Wang M.S. James Babb Ph.D. Suzanne M. Miller Ph.D. John A. Ridge M.D. Ph.D. Benjamin Movsas M.D. Corey Langer M.D. Michael Unger M.D. Melvyn Goldberg M.D. 《Annals of behavioral medicine》2003,25(3):214-221
Even though continued smoking by cancer patients adversely affects survival and quality of life, about one third of patients
who smoked prior to their diagnosis continue to smoke after their diagnosis. The implementation of smoking cessation treatments
for cancer patients has been slowed by the lack of data on correlates of tobacco use in this population. Thus, this longitudinal
study assessed demographic, medical, addiction, and psychological predictors of tobacco use among 74 head, neck, and lung
cancer patients. Multivariable binary logistic regression analyses, with outcome categorized as smoker or nonsmoker, indicated
that the likelihoodthat patients would be a smoker was associated with lower levels of perceived risk and a higher level of
quitting cons. Multivariable nominal logistic regression, with outcome classified as continuous smoker, continuous quitter,
relapser, or follow-up quitter, indicated that: (a) patients categorized as continuous smokers reported significantly lower
quitting self-efficacy than follow-up quitters and continuous quitters, (b) relapsers reported a significantly lower level
of quitting self-efficacy than either follow-up quitters or continuous quitters, and (c) continuous smokers exhibited a significantly
lower level of risk perceptions than continuous abstainers. These findings can be useful for the development and evaluation
of treatments to promote smoking cessation among cancer patients.
Support for this study was provided by National Institutes of Health Grants CA57708, CA06927, CA88610, CA95678, and CA76644. 相似文献