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41.
Objectives:Congenital heart defects (CHD) are the most prevalent congenital anomalies. This study aims to examine the association between maternal occupational exposures to organic and mineral dust, solvents, pesticides, and metal dust and fumes and CHD in the offspring, assessing several subgroups of CHD.Methods:For this case–control study, we examined 1174 cases with CHD from EUROCAT Northern Netherlands and 5602 controls without congenital anomalies from the Lifelines cohort study. Information on maternal jobs held early in pregnancy was collected via self-administered questionnaires, and job titles were linked to occupational exposures using a job exposure matrix.Results:An association was found between organic dust exposure and coarctation of aorta [adjusted odds ratio (ORadj) 1.90, 95% confidence interval (CI) 1.01–3.59] and pulmonary (valve) stenosis in combination with ventricular septal defect (ORadj 2.68, 95% CI 1.07–6.73). Mineral dust exposure was associated with increased risk of coarctation of aorta (ORadj 2.94, 95% CI 1.21–7.13) and pulmonary valve stenosis (ORadj 1.99, 95% CI 1.10–3.62). Exposure to metal dust and fumes was infrequent but was associated with CHD in general (ORadj 2.40, 95% CI 1.09–5.30). Exposure to both mineral dust and metal dust and fumes was associated with septal defects (ORadj 3.23, 95% CI 1.14–9.11). Any maternal occupational exposure was associated with a lower risk of aortic stenosis (ORadj 0.32, 95% CI 0.11–0.94).Conclusions:Women should take preventive measures or avoid exposure to mineral and organic dust as well as metal dust and fumes early in pregnancy as this could possibly affect foetal heart development.  相似文献   
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Diet, weight–bearing physical activity (WPA) and daylight hours spent outdoors (DE) were related to bone mineral density in the distal (BMDd) and ultradistal (BMDud) forearm of 495 healthy children (8–11 years) and adolescents (11–17 years). BMD was assessed by single photon absorptiometry. Using multiple regression, BMDd was predicted by saturated fat and BMDud by fiber in children. In adolescents, BMDd was predicted by saturated fat and vitamin C, and BMDud by calcium and vitamin C. WPA and DE were not related to BMD. In conclusion, our results showed that current intake of calcium, saturated fat, fiber and vitamin C were positively associated with forearm BMD in children and adolescents. These associations depended on age and bone type. If our findings are verified, dietary recommendations, especially when aimed at young people, may have to be reconsidered.  相似文献   
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To determine predictive values of routine semen analysis, sperm morphology evaluation using strict criteria and DNA status for in-vitro fertilization (IVF), 66 consecutive couples undergoing IVF in a university hospital IVF programme were prospectively investigated. Semen samples from 66 men were evaluated by routine semen analysis, morphology evaluation using strict criteria and acridine orange staining for determination of DNA status. A new technique is described for acridine orange scoring which consisted of evaluation of two smears per case, with and without heat treatment. Resistance to heat-provoked denaturation was determined by the difference between two evaluations. A logistic regression model was built and receiver operating characteristic curves were constructed to determine the threshold values and to compare diagnostic properties. Morphology evaluation using strict criteria and concentration of progressively motile spermatozoa were found to be the principal parameters determining the sperm fertilizing capacity in vitro. The logistic regression model composed of morphology evaluation using strict criteria and acridine orange score had a powerful diagnostic capability for prediction of fertilization in vitro.   相似文献   
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An electrocardiographic (ECG) sensing and gating device compatible with a 0.35-tesla (T) magnetic resonance (MR) imager has been developed and used to produce 802 MR images of the heart in 30 patients. The instrument consists of an isolated acquisition module, an electrically floating preamplifier, and a monitor gating module. Two spin-echo images were acquired for each of five, 0.7-cm thick, transaxial sections from the base to the apex of the heart during each ECG-synchronized imaging run. Image quality was assessed in a blind study by two investigators, on a scale from 0 to 3, as diagnostic [2-3] or nondiagnostic [0-1]. There was agreement in 91.4% of their assessments of diagnostic images (68.1% of the images studied). Resolution of heart anatomy on the MR images was adversely affected by prolonged spin-echo time delay, imaging in late diastole, image acquisition at the cardiac apex, irregular triggering, and artifacts. The synchronization of gradient pulses to the ECG at 0.35 T appears safe for patients, permits diagnostic resolution of images, allows image acquisition at distinct points during the cardiac cycle, and enables monitoring of patients during imaging.  相似文献   
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