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Rapid advances in graphics computing and micro-engineering have offered new techniques for prenatal cardiac imaging. Some of them can be non-invasively applied to both clinical and laboratory settings, including dynamic three-dimensional echocardiography, myocardial Doppler imaging, harmonic ultrasound imaging, and B-flow sonography. With clinical constraints, a few others have been mainly used in laboratories, such as endoscopic ultrasound, magnetic resonance imaging and biomicroscopy. Appropriate use and co-use of these new tools will not only provide unique information for better clinical assessment of fetal cardiac disease but also offer new ways to improved understanding of cardiovascular development and pathogenesis. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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The present study describes an association between adverse outcome in the twin-to-twin transfusion syndrome (TTTS) and pulmonary stenosis or reactive right ventricular hypertrophy. Six discordant monozygotic twin pregnancies with TTTS are described. Ventricular hypertrophy and atrioventricular valvular regurgitation occurred in all the recipient twins with pulmonary valvular stenosis in three cases and infundibular stenosis in one case. The recipient twin in one pair and both twins in another pregnancy died as a consequence of immaturity but the remaining twins all survived. Surgical intervention was required in one baby for valvular pulmonary stenosis. Our observations suggest that elevated blood pressure in the transfusion recipient may play an important role in pathogenesis. We hypothesise that both pulmonary stenosis and right chamber hypertrophy are secondary to hemodynamic changes. Although we have found valvular pulmonary stenosis in three recipients and infundibular stenosis in only one, this (obstruction to outflow) could be due to right chamber hypertrophy. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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为了研究人群在自然属性和社会属性分类下的效应修饰作用,利用2005~2011年北京市大气PM2.5日均浓度、气象要素及循环系统疾病每日死亡人数数据,根据不同年龄、性别及学历将人群分组,采用时间序列的半参数广义相加模型(GAM),定量评价大气PM2.5对居民循环系统疾病死亡人数的影响.单污染物模型和多污染物模型结果表明,PM2.5为影响循环系统疾病每日死亡人数的主要大气污染物.北京市空气中PM2.5的浓度每增加10μg/m3,循环系统疾病总死亡人数增加0.50%(95% CI:0.36,0.63).不同人群的易感程度不同,各人群死亡人数的增加范围为0.23~0.71%,女性、60~74岁人群、文盲人群的健康风险相对较高.在文盲人群中,老年(60+)女性占比为66.2%,为了分离社会属性人群分类中可能存在的自然属性因素干扰,本文去除其中老年、女性这两个混杂因素的影响,文盲人群健康风险仍然大于较高学历的人群.年龄和性别因素叠加在学历因素上,可能加大低学历人群的健康风险,对于这部分叠加了自然因素和社会因素双重敏感性的人群应给与重点关注.  相似文献   
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There has been tremendous development in the field of prenatal diagnosis of cardiac disease in the last 30 years. Early work centered on the technical aspects of providing an accurate assessment of cardiac structure and function. Techniques of fetal cardiac screening have been developed and utilized throughout the world. More recently, investigators have begun to explore the ramifications of fetal cardiac diagnosis by assessing measures of outcome. In this article, the field of fetal echocardiography, as a screening tool for identifying congenital heart disease, and its impact on disease outcome is reviewed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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Non-mosaic trisomy 20 is rare in fetuses surviving beyond the first trimester. We report a case of a fetus with non-mosaic trisomy 20 in amniotic fluid cultures obtained during the prenatal evaluation of an unusual thoraco-abdominal mass which was found at autopsy to be pulmonary sequestration. Gross inspection and autopsy of the fetus revealed multiple anomalies. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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During Malaysia’s rapid economic development into becoming a middle income country in the past several decades, environmental changes resulted in altered land use patterns because of agricultural practices such as large scale rice, rubber and oil palm cultivation. The impact of environmental changes brought about by rice and rubber cultivation affected the breeding habitats of mosquito vectors which in turn affected the prevalence of two strains of lymphatic filariasis in different ways. With scrub typhus, the development of oil palm plantations affected the ecology of mite and rodent populations which resulted in very high incidence of the disease in affected populations. Malaysia’s relentless urbanization has resulted in increased incidence of dengue, as peridomestic mosquito vectors increasingly colonize urban habitats. This article discusses how ecological factors determine the way lymphatic filariasis, scrub typhus and dengue were spread in Malaysia. The nation’s experience with environmental changes due to rapid development provides lessons for other developing countries in control programs and public health policy.  相似文献   
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