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Congenital malformations in twins: an international study   总被引:9,自引:0,他引:9  
Data provided by nine registries based in European and Latin America countries were analyzed to assess whether there is an excess of malformations in twins compared to singletons. Specific congenital malformations were coded according to the ninth revision of the International Classification of Diseases (ICD). Malformation rates and rate ratios (RR) for twins compared to singletons were calculated for each registry, and the homogeneity of the RRs was tested using the test of Breslow and Day. If departure from homogeneity in the different registries was not significant, registry-adjusted RRs with 95% confidence intervals were calculated. Overall, among 260,865 twins, 5,572 malformations were reported. A total of 101 different types of malformations or groups of defects was identified, and a homogeneous estimate of the RRs among registries was found for 91.1% of the malformations. Thirty-nine of the 92 malformations with homogeneous estimates of RRs were more common in twins than in singletons. For the remaining nine malformations, heterogeneous estimates of RRs were obtained. This study confirms the majority of already known associations and further identifies previously unreported malformations associated with twins. In conclusion, there is an excess of malformations in twins compared with singletons, and all anatomical sites are involved. The number of specific malformations associated with twins is higher than that previously reported in smaller studies.  相似文献   
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When posing for portraits people tend to offer their left cheek. This bias is also evident in selfies: informal photographic self-portraits taken with a smartphone. Mechanical biases have been argued to influence selfie posing orientation (predicting that using the left hand favours a stronger left cheek bias), however this hypothesis has not been directly tested. The present study was thus designed to determine whether motor biases influence selfie pose orientation. Three hundred and twenty participants (F?=?159, M?=?161) were asked to pose for a selfie “as you really are,” and completed a handedness measure; hand used to take the selfie and selfie pose orientation were recorded. Ordinal logistic regression confirmed that neither participant handedness nor hand used to capture the selfie predicted selfie pose orientation. Regardless of sex, handedness, or hand used, participants were more likely to present a midline (49.75%) than a left (26.53%) or right (26.72%) cheek pose. Though handedness was a strong predictor of hand used to capture the selfie (left handers favour the left, and right handers the right, hand), it did not predict posing orientation. These results confirm that selfie cheek biases are not simply a residual effect of the mechanics of taking selfies.  相似文献   
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The purpose of the present study was to compare and evaluate the new Helsinki Alcohol Use Test (HAUT) and Alcohol Use Disorders Identification Test (AUDIT) as screening instrument in the general working population. The relationship between the HAUT and serum gamma-glutamyl transferase (GGT), and carbohydrate-deficient transferrin (CDT) was also evaluated. Our results seem to indicate that the HAUT has good performance as screening instrument for alcohol-related problems in the general population.  相似文献   
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The aim of this study was to estimate the prevalence of vesicoureteral reflux (VUR) and clinically significant ultrasonography (US) abnormalities in a large group of children with proven and suspected urinary tract infection (UTI). The medical reports on renal US and voiding cystouretrographies (VCUG) of 2,036 children were reviewed. Renal US was performed on all children and VCUG on 1,185 children (58%). Based on the urine culture data, the UTI diagnoses were classified into five reliability classes (proven, likely, unlikely, false and no microbial data). The UTI diagnose was considered proven in 583/2036 (28.6%) and false in 145 (7.1%) cases. The prevalence of VUR was similar among those with proven and false UTI [37.4 vs. 34.8%; relative risk (RR) 1.08, 95% confidence intervals (95% CI) 0.7–1.7, P = 0.75] and decreased with increasing age (P = 0.001). Clinically significant US abnormalities occurred in 87/583 (14.9%) cases with proven UTI and significantly less often (11/145, 7.6%) in the false UTI class (RR 1.96, 95% CI 1.1–3.6, P = 0.02). Our finding supports the claim that VUR is not significantly associated to UTI and that its occurrence among children even without UTI is significantly higher than traditional estimates. This challenges the recommendations of routine VCUG after UTI.  相似文献   
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