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The aim of this paper was to review the clinical applications of four-dimensional ultrasonography in the assessment of fetal behavior. With the use of a computerized database, articles on three-dimensional ultrasonography were reviewed. Several applications of dynamic three-dimensional ultrasonography have been reported, including imaging of fetal movements, facial expression and fetal hand movements. The importance of the assessment of fetal behavior by four-dimensional sonography is stressed. Four-dimensional sonography seems to be a useful imaging tool for clinical problem solving in perinatology, especially in observing the development of the central nervous system in utero.  相似文献   
83.
Background: We wished to examine the impact of the duration and intensity of physical activity on common anxiety and depressive states. Method: A nested case-control design was applied to data from the Health and Lifestyle Survey. Anxiety and depressive states were measured by caseness on the General Health Questionnaire. Physical activity variables were defined from a detailed activity schedule. Results: After adjustment for potential confounders, the findings suggest that compared to men who reported 0–44 min of daily physical activity, there is benefit to men who exercise for at least 92 min a day (92–161 min a day: OR = 0.57, 95% CI = 0.37–0.87, P < 0.01; 162–554 min a day: OR = 0.65, 95% CI = 0.43–0.97, P < 0.05), but not to women. The protective effect does not appear to vary according to the intensity of activity in men or women. Conclusions: Physical activity of long duration amongst men confers protection against common mood and anxiety states. This study found no such protection for women. Accepted: 21 October 1999  相似文献   
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We reviewed all English-language articles on associations among circulating levels of the insulin-like growth factors (IGF) and their binding proteins (IGFBP), polymorphisms in their genes, and breast cancer risk. In premenopausal women, five of eight IGF-I studies and four of six IGFBP-3 studies of circulating levels found that women in the highest quantile had more than twice the risk of developing breast cancer of those in the lowest, although in some this effect was only apparent at young ages. In postmenopausal women, however, there was no consistent effect. A simple sequence length polymorphism 1 kb 5' to IGF-I was examined in relation to circulating levels of IGF-I (12 studies) or breast cancer risk (4 studies), but there was no convincing evidence of any effect. For an A/C polymorphism 5' to IGFBP-3, all three studies were consistent with a modest effect on circulating levels, but no evidence of a direct effect on breast cancer risk was seen in the only relevant study. Variation within the reference range of IGF-I and IGFBP-3 may confer only modest increases in breast cancer risk, and any single polymorphism may only account for a small proportion of that variation. Nevertheless, population attributable fractions for high circulating levels of IGF-I and IGFBP-3 and for common genetic variants could be substantial. Further large studies, or combined analysis of data from existing studies, are needed to quantify these effects more precisely.  相似文献   
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Glucocorticoid suppressible hyperaldosteronism (GSH) is an uncommon form of dominantly inherited hypertension. Presentation with hypertension and complications such as stroke in early life are well recognised. The use of a simple genetic test carried out on blood or placenta facilitates the detection of infants and children with GSH before the development of hypertension, allowing prompt treatment of hypertension if it occurs, and an opportunity to study the effects of growth and environmental influences on the progression of the condition.  相似文献   
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The ability of dynamic, gadolinium-enhanced magnetic resonance (MR) imaging to allow prediction of histologic responses to initial chemotherapy was evaluated in 20 patients with osteosarcoma (n = 12), Ewing sarcoma (n = 4), rhabdomyosarcoma (n = 3), or synovial sarcoma (n = 1). Tumor signal intensity was measured on fast low-angle shot (FLASH) gradient-echo images obtained at 15-second intervals before and 3 or more minutes after manual intravenous injection of gadopentetate dimeglumine. Signal intensity was plotted against time, and slopes were calculated for the percentage increase in signal intensity per minute. Slopes and changes in maximum tumor size during and after chemotherapy were correlated with histologic evaluations of tumor response. Eleven of the 20 tumors met histologic criteria for response. Histologic response was moderately correlated with slopes obtained during chemotherapy (rs [Spearman rank correlation] = .53, P = .02) but not with changes in tumor size (rs = .02, P = .94). Tumor slopes obtained after chemotherapy were highly correlated with histologic findings (rs = .65, P = .007); the correlation with changes in tumor size increased but remained nonsignificant (rs = .41, P = .11).  相似文献   
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