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We present a case report on a fetus with multiple malformations, diagnosed by ultrasound at 20 weeks' gestation. From the combination of intrauterine growth retardation and limb abnormalities that were observed, the most likely diagnosis was considered to be Cornelia de Lange Syndrome (CdLS). Following counselling, the mother opted to terminate the pregnancy. Chromosome analysis of cultured amniotic fluid cells showed a karyotype of 46,XX,t(3;5)(q21;p13). Postmortem examination of the baby confirmed the presence of features consistent with a diagnosis of CdLS. This case provides a report of a definitive diagnosis of Cornelia de Lange Syndrome, suspected on the basis of ultrasound imaging and confirmed by amniocentesis findings. Copyright © 2005 John Wiley & Sons, Ltd.  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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A retrospective study to investigate the psychosocial sequelae of a second-trimester termination of pregnancy (TOP) for fetal abnormality (FA) is described. After appropriate consent was obtained, 84 women and 68 spouses were visited 2 years after the event and asked to complete an extensive questionnaire. Most couples reported a state of emotional turmoil after the TOP. There were differences in the way couples coped with this confusion of feelings. After 2 years about 20 per cent of the women still complained of regular bouts of crying, sadness, and irritability. Husbands reported increased listlessness, loss of concentration, and irritability for up to 12 months after the TOP. In the same period, there was increased marital disharmony in which 12 per cent of the couples separated for a while and one couple obtained a divorce. These problems could be attributed to a lack of synchrony in the grieving process. Confusing and conflicting feelings led to social isolation and lack of communication. Difficulties in coming to terms with the fetal loss were not found to be linked to the type of fetal abnormality or religious beliefs but were related to parental immaturity, inability to communicate needs, a deep-rooted lack of self-esteem before the pregnancy, lack of supporting relationships, and secondary infertility. Suggestions for improved management are given.  相似文献   
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Experience with prenatal karyotyping of 237 fetuses with sonographic evidence of malformation is reported. Abnormal karyotype was found in 40 cases (16-8 per cent): chromosomal aberrations were found in 19 of the 178 fetuses with an isolated structural anomaly (10-6 per cent) and in 21 of the 59 fetuses with multiple malformations (35-6 per cent). Detailed cytogenetic and morphological information concerning fetuses affected by omphalocele, duodenal atresia, hydrocephalus, multicystic kidney, unilateral hydronephrosis and cystic hygroma is reported. The need for a very careful ultrasound evaluation of fetal anatomy in these pregnancies is stressed, as the risk of a chromosomal anomaly depends mainly on the existence of more than one ultrasonically diagnosed structural defect.  相似文献   
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广西夏季异常降雨量的前馈网络预报模型   总被引:1,自引:0,他引:1  
以1957~2001年广西37个基准站的夏季(6~8月)平均降水量为基础,将夏季降水量距平百分率大于等于20%、小于等于-23%作为异常多雨和少雨年,建立广西夏季降水量"0、1"化的异常序列,利用前馈网络的非线性映射技术,构造广西夏季降水异常预报模型.通过对该模型的预报检验分析发现,该预报模型不仅能准确地报出历史样本的异常多雨和异常少雨年,并且对2002~2004年的独立样本预报也全部正确.这为异常降水的短期气候预测业务工作提供了新的思路和方法.  相似文献   
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Objectives Support after fetal diagnosis of abnormality (SAFDA), is a facilitated shared experience group for women and their partners or support person, in Victoria, Australia, who have had a pregnancy termination for a fetal abnormality. The objective of this study was to evaluate the SAFDA-facilitated group. Methods A questionnaire-based study was undertaken between 2001 and 2005 to evaluate SAFDA. A deidentified self-completed questionnaire was given to participants at the end of each group and included questions relating to the referring professional, participants' prior expectations of the group, helpfulness of participation, preferred group format, length, and venue. In addition, there was also opportunity for participants to make general comments on their experiences of participating in SAFDA. Results A total of 85 participants (100% response) completed the questionnaire. Seventy-one participants (84%) considered it ‘very helpful’ to participate in the group. Seventy-eight participants (92%) considered that a shared-experience group was the most beneficial format. Comments written by participants affirmed that the present format of SAFDA was a highly valued opportunity to listen to and share experiences in a confidential small group. Conclusion SAFDA is a beneficial forum for women and their partners or support person to share their experiences after having had a pregnancy termination for a fetal abnormality. Further, SAFDA provides information and insights for health professionals who are considering how best to support women. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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Summary Our paper addresses field survivorship of first instar monarch butterfly larvae (Danaus plexippus L., Lep.: Danainae) in relation to the dual cardenolide and latex chemical defenses of the sand hill milkweed plant,Asclepias humistrata (Asclepiadaceae) growing naturally in north central Florida. Survival of first instar larvae in the field was 11.5% in the first experiment (15–20 April 1990), and dropped to 3.4% in the second experiment (20–30 April). About 30% of the larvae were found glued to the leaf surface by the milkweed latex. Predator exclusion of non-flying inverte-brates by applying tanglefoot to the plant stems suggested that the balance of the mortality was due to volant inverte-brates, or to falling and/or moving off the plants. Regression analyses to isolate some of the other variables affecting survivorship indicated that first instar mortality was correlated with (1) increasing cardiac glycoside concentration of the leaves, (2) increasing age of the plants, and (3) the temporal increase in concentration of cardiac glycosides in the leaves. The study also provided confirmatory data of previous studies that wild monarch females tend to oviposit onA. humistrata plants containing intermediate concentrations of cardiac glycosides. Cardiac glycoside concentration in the leaves was not correlated with that in the latex. The concentration of cardenolide in the latex is extremely high, constituting an average of 1.2 and 9.5% of the mass of the wet and dry latex, respectively. The data suggest that an increase in water content of the latex is compensated for by an influx of cardenolide with the result that the cardenolide concentration remains constant in the latex systems of plants that are growing naturally. We also observed first instar larvae taking their first bite of milkweed leaves in the field. In addition to confirming other workers findings that monarch larvae possess elaborate sabotaging behaviour of the milkweed's latex system, we discovered that several larvae on their first bite involuntarily imbided a small globule of latex and instantly became cataleptic. This catalepsis, lasting up to 10 min, may have been in response to the high concentration of cardenolide present in the latex ofA. humistrata, more than 10 times that in the leaves. The results of the present study suggest that more attention should be directed to plant chemical defenses upon initial attack by first instar insect larvae, rather than attempting correlations of plant chemistry with older larvae that have already passed the early instar gauntlet. The first bite of neonate insects may be the most critical moment for coping with the chemical defenses of many plants and may play a much more important role in the evolution of insect herbivory than has previously been recognized.  相似文献   
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Thirty-one genetic amniocenteses involving multiple gestations were performed in the genetics unit between 1976 and 1982. Three sets of triplets were included. Precise locations of the sacs were determined using real-time ultrasonography and successful sampling of all sacs was accomplished. Spontaneous abortions occurred in two normal twins and one normal triplet gestation. Two therapeutic abortions were performed for fetal abnormalities. Two cases of discordance for trisomy 21 (one twin and one triplet) were allowed to continue; the twin case terminated at 25 weeks' gestation with neonatal deaths and the triplets are alive and well.  相似文献   
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