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ObjectiveTo assess site-specific cancer risk in the Baltic cohort of Chernobyl cleanup workers, 1986–2007.MethodsThe Baltic cohort includes 17,040 men from Estonia, Latvia and Lithuania who participated in the environmental cleanup after the accident at the Chernobyl Nuclear Power Station in 1986–1991 and who were followed up for cancer incidence until the end of 2007. Cancer cases diagnosed in the cohort and in the male population of each country were identified from the respective national cancer registers. The proportional incidence ratio (PIR) with 95% confidence interval (CI) was used to estimate the site-specific cancer risk in the cohort. For comparison and as it was possible, the site-specific standardised incidence ratio (SIR) was calculated for the Estonian sub-cohort, which was not feasible for the other countries.ResultsOverall, 756 cancer cases were reported during 1986–2007. A higher proportion of thyroid cancers in relation to the male population was found (PIR = 2.76; 95% CI 1.63–4.36), especially among those who started their mission shortly after the accident, in April–May 1986 (PIR = 6.38; 95% CI 2.34–13.89). Also, an excess of oesophageal cancers was noted (PIR = 1.52; 95% CI 1.06–2.11). No increased PIRs for leukaemia or radiation-related cancer sites combined were observed. PIRs and SIRs for the Estonian sub-cohort demonstrated the same site-specific cancer risk pattern.ConclusionConsistent evidence of an increase in radiation-related cancers in the Baltic cohort was not observed with the possible exception of thyroid cancer, where conclusions are hampered by known medical examination including thyroid screening among cleanup workers.  相似文献   
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Recent studies have reported on an association between endurance sport, atrial enlargement and the development of lone atrial fibrillation in younger, male cohorts. The atrial morphology and function of middle‐aged, physically‐active males and females have not been well studied. We hypothesized that middle‐aged males would demonstrate larger left atrium (LA) and right atrium (RA) volumes compared to females, but atrial function would not differ. LA and RA volume and function were evaluated at rest in healthy adults, using a standardized 3.0Tesla cardiac magnetic resonance protocol. Physical activity, medical history, and maximal oxygen consumption (V˙O2peak) were also assessed. Physically‐active, middle‐aged men (n = 60; 54 ± 5 years old) and women (n = 30; 54 ± 5 years old) completed this study. Males had a higher body mass index, systolic blood pressure, and V˙O2peak than females (p < .05 for all), despite similar reported physical activity levels. Absolute and BSA and height‐indexed LA and RA maximum volumes were higher in males relative to females, despite no differences in ejection fractions (p < .05 for all). In multivariable regression, male sex p < .001) and V˙O2peak (p = .004) were predictors of LA volume (model R 2 = 0.252), whereas V˙O2peak (p < .001), male sex (p = .03), and RV EF (p < .05) were predictors of RA volume (model R 2 = 0.377). While middle‐aged males exhibited larger atrial volumes relative to females, larger, prospective studies are needed to explore the magnitude of physiologic atrial remodeling and functional adaptations in relation to phenotypic factors.  相似文献   
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The purpose of this study was to examine the influence of the energy cost of swimming, body composition, and technical parameters on swimming performance in young swimmers. Twenty-nine swimmers, 15 prepubertal (11.9 +/- 0.3 years; Tanner Stages 1-2) and 14 pubertal (14.3 +/- 1.4 years; Tanner Stages 3-4) boys participated in the study. The energy cost of swimming (Cs) and stroking parameters were assessed over maximal 400-m front-crawl swimming in a 25-m swimming pool. The backward extrapolation technique was used to evaluate peak oxygen consumption (VO2peak). A stroke index (SI; m2 . s(-1) . cycles(-1)) was calculated by multiplying the swimming speed by the stroke length. VO2peak results were compared with VO2peak test in the laboratory (bicycle, 2.86 +/- 0.74 L/min, vs. in water, 2.53 +/- 0.50 L/min; R2 = .713; p = .0001). Stepwise-regression analyses revealed that SI (R2 = .898), in-water VO2peak (R2 = .358), and arm span (R2 = .454) were the best predictors of swimming performance. The backward-extrapolation method could be used to assess VO2peak in young swimmers. SI, arm span, and VO2peak appear to be the major determinants of front-crawl swimming performance in young swimmers.  相似文献   
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The objective of this study was to calculate an oxidative balance score (OBS) utilizing diet and lifestyle information collected from 1322 women during the second trimester of pregnancy in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood study. An energy-adjusted OBS was calculated using nutrient information from a Food Frequency Questionnaire (FFQ), lifestyle measures, and plasma folate and vitamin D levels. Using the least absolute shrinkage and selection operator method, 91 food items from the FFQ were selected and they accounted for 82% of the variance in the OBS, with cruciferous vegetables, citrus fruits, fruit juice, and coffee being among the highest anti-oxidant predictors, and red meats and alcohol among the highest pro-oxidant contributors. Urinary F2-isoprostane, an objective indicator of oxidative stress, was lower with increasing OBS quintiles in a stairstep manner (p for trend = 0.0003), suggesting the possible utility of the OBS as an indicator of oxidative stress. The OBS was moderately correlated with the Healthy Eating Index (correlation coefficient = 0.6076), suggesting it provides a distinct measure of a healthy diet. In conclusion, the OBS may serve as a valid reflective indicator of urinary F2-isoprostanes and an epidemiological tool to inform intervention studies, in order to minimize oxidative stress during pregnancy.  相似文献   
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Since the introduction of laparoscopic cholecystectomy (LC), an increase in accidental common bile duct (CBD) injuries of up to 1.2-1.6% has been reported. In the present prospective study of 1,710 patients undergoing cholecystectomy (1,241 LC procedures and 469 open cholecystectomies [OC]), we tested the predicative value of routine intraoperative cholangiography (IOC). The IOC was feasible in 92.4% of the cases in the LC group and in 83% of cases in the OC group and presented a complete depiction of the extrahepatic bile system in 98.3%. Anatomic variations of the bile duct system, which influenced the operative management, were found in 13.2% of cases (13.4% LC versus 12.8% OC). In 2.5% of the patients, preoperatively undetected CBD stones were also found. Method-specific complications did not occur in any of the patients. Additionally, in a controlled subgroup analysis of 163 patients, we evaluated preoperative intravenous cholangiography (IVC) and IOC. Intravenous cholangiography showed only 72.4% of the operation-relevant anatomic variations (vs. 100% by IOC); in 6.1% of the cases, there were reactions to the dye (vs. none in IOC), and in only 28.6% of the patients, CBD stones were detected (vs. 71.4% IOC). There were four bile duct injuries (0.29%) during LC and two (0.4%) during OC. All injuries were detected intraoperatively and fixed in the same setting without postoperative complications. In conclusion, we recommend the use of routine IOC during cholecystectomy. By this technique, anatomic variations of the bile duct system will be visualized and therefore accidental injuries will be avoided.  相似文献   
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