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31.
An Erratum has been published for this article in Prenatal Diagnosis 21(7) 2001, 605. Prenatal diagnosis (PD) of fetal cytomegalovirus (CMV) infection was performed in 242 pregnancies, with known outcome in 189 cases. In 141/189 pregnancies, PD was carried out on account of suspicious maternal CMV serology up to gestational week (WG) 23, and in 48 cases on account of abnormal ultrasonic findings detected between WG 18 and 39. Chorionic villus samples (n=6), amniotic fluid (AF, n=176) and/or fetal blood specimens (n=80) were investigated for detection of virus by cell culture, shell vial assay, PCR and/or CMV-specific IgM antibodies. Of 189 fetuses correctly evaluated by CMV detection either in fetal tissue following therapeutic abortion/stillbirth (n=24) or in urine of neonates within the first 2 weeks of life (n=33), 57 were congenitally infected. In women with proven or suspected primary infection, the intrauterine transmission rates were 20.6% (7/34) and 24.4% (10/41), respectively. Of the congenitally infected live-born infants, 57.6% (19/33) had symptoms of varying degree. The overall sensitivity of PD in the serologic and ultrasound risk groups was 89.5% (51/57). A sensitivity of 100% was achieved by combining detection of CMV-DNA and CMV-specific IgM in fetal blood or by combined testing of AF and fetal blood for CMV-DNA or IgM antibodies. There was no instance of intrauterine death following the invasive procedure. The predictive value of PD for fetal infection was 95.7% (132/138) for negative results and 100% (51/51) for positive results. Correct results for congenital CMV infection by testing AF samples can be expected with samples obtained after WG 21 and after a time interval of at least 6 weeks between first diagnosis of maternal infection and PD. In case of negative findings in AF or fetal blood and the absence of ultrasound abnormalities at WG 22–23, fetal infection and neonatal disease could be excluded with high confidence. Positive findings for CMV infection in AF and/or fetal blood in combination with CMV suspicious ultrasound abnormalities predicted a high risk of cytomegalic inclusion disease (CID). Furthermore, detection of specific IgM antibodies in fetal blood was significantly correlated with severe outcome for the fetus or the newborn (p=0.0224). However, normal ultrasound of infected fetuses at WG 22–23 can neither completely exclude an abnormal ultrasound at a later WG and the birth of a severely damaged child nor the birth of neonates which are afflicted by single manifestations at birth or later and of the kind which are not detectable by currently available ultrasonographic techniques. Copyright © 2001 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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We report three siblings from consecutive pregnancies affected with restrictive dermopathy (RD). During the second pregnancy, fetal behavioural development and growth were studied extensively using ultrasound at 1–4 week intervals. Dramatic and sudden changes occurred in fetal body movements and growth but not until the end of the second trimester of pregnancy. Prominent at that time were prolonged periods of fetal quiescence and very low heart rate variability, together with abnormally executed body movements of short duration. Retarded femoral development and jerky abrupt fetal body movements (abnormal movement quality) were already present in the early second trimester of pregnancy. Facial anomalies emerged despite the presence of fetal mouth movements. The clinical features of RD were only partly explained by present knowledge of skin development and the fetal akinesia deformation sequence hypothesis. Quantitative assessment of fetal movements proved to be a poor early marker for antenatal diagnosis of this disorder. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Originally prenatal diagnosis was confined to the diagnosis of metabolic disorders and depended on assaying enzyme levels in amniotic fluid. With the development of recombinant DNA technology, molecular diagnosis became possible for some genetic conditions late in the 1970s. Here we briefly review the history of molecular prenatal diagnostic testing, using Duchenne muscular dystrophy as an example, and describe how over the last 30 years we have moved from offering testing to a few affected individuals using techniques, such as Southern blotting to identify deletions, to more rapid and accurate PCR-based testing which identifies the precise change in dystrophin for a greater number of families. We discuss the potential for safer, earlier prenatal genetic diagnosis using cell free fetal DNA in maternal blood before concluding by speculating on how more recent techniques, such as next generation sequencing, might further impact on the potential for molecular prenatal testing. Progress is not without its challenges, and as cytogenetics and molecular genetics begin to unite into one, we foresee the main challenge will not be in identifying the genetic change, but rather in interpreting its significance, particularly in the prenatal setting where we frequently have no phenotype on which to base interpretation. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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In a case of fetal heart failure caused by endocardial fibroelastosis, prenatal echocardiography clearly demonstrated; a thickened endocardium. We therefore suggest that an abnormal endocardium may be detected in utero by ultrasound, thus representing an important clue in the differential diagnosis of fetal nonimmune hydrops and in the evaluation of pregnancies at risk for endocardial fibroelastosis.  相似文献   
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蒋玫  沈新强  李磊  黄厚见 《生态环境》2010,19(12):2906-2910
以中华绒螯蟹(Eriocheir sinesis)仔蟹为研究对象。采用静水试验法,温度在20℃左右,用氨氮与过滤海水分设5个质量浓度组(2.04、6.35、9.04、11.75和19.13 mg.L-1),同时以过滤海水为对照组(氨氮质量浓度为0.30 mg.L-1),每一个质量浓度组设3个平行样本,对中华绒螯蟹仔蟹进行6 d胁迫试验。每2 d观察仔蟹的蜕壳情况,并分别于实验后的2、4和6 d取仔蟹肝组织样,应用激光共聚焦技术分析测定RNA/DNA荧光相素比,同时用透射电镜观察6 d后,最高浓度组和对照组仔蟹肝细胞结构的变化情况。试验结果表明;对于氨氮的胁迫,仔蟹的变态率随染毒浓度的增高而降低,同时变态蜕壳的时间也会产生延迟现象。氨氮的胁迫会引起仔蟹的肝组织细胞内的DNA和RNA的质量分数逐渐降低,导致RNA/DNA比率的不断下降。在高质量浓度氨氮的胁迫下,使得仔蟹肝细胞线粒体部分解体、胞质空泡化和染色质浓缩、转运泡数量增多,体积增大,细胞出现许多空泡和微绒毛消失等一系列的损伤变化。破坏了仔蟹自身机能正常的代谢和生长水平。  相似文献   
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