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791.
Genome sequencing is increasingly being used to aid genetic diagnosis in fetuses with structural abnormalities detected on ultrasound examination. However, with clinical exome and genome sequencing, there is potential for the recognition and reporting of incidental or secondary findings unrelated to the indication for ordering the sequencing, but of potential medical value for patient care. In the postnatal setting, the American College of Medical Genetics and Genomics (ACMG) has clear guidelines that state that when offering sequencing, secondary findings should be reported in 59 genes for which ACMG consider there is a clinical evidence that pathogenic variants may result in disease that might be prevented or treated, with the option to opt out of receiving this information. However, these guidelines specifically exclude prenatal sequencing. Here, we report the debate on whether or not pathogenic findings in these 59 genes should or should not be reported in the prenatal setting. Although more were in favour of reporting before the debate, there was no significant consensus from the audience. After the debate there was a swing toward not reporting, but a slim majority (55%) remained in favour, indicating that this is an area requiring further research and the development of evidence-based guidelines applicable to prenatal proband and trio sequencing. 相似文献
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Maria Neofytou Nathalie Brison Kris Van den Bogaert Luc Dehaspe Koen Devriendt Anja Geerts Joris R. Vermeesch 《黑龙江环境通报》2018,38(2):148-150
Noninvasive prenatal testing (NIPT) can very accurately determine fetal sex during pregnancy. We present an exceptional case where NIPT contradicts the ultrasound-based sex determination. The pregnant woman was recipient of a liver transplant from a male donor. Graft-derived cell-free DNA released into the maternal circulation clouded the NIPT-based sex determination. Hence, NIPT is not advisable when the pregnant mother underwent an organ transplant. 相似文献
794.
Alyaa AlRefai James Drake Abhaya V. Kulkarni Kristin L. Connor Patrick Shannon Ants Toi David Chitayat Susan Blaser Paige T. Church Nimrah Abbasi Greg Ryan Tim Van Mieghem 《黑龙江环境通报》2019,39(1):10-15
此文以霸县凹陷文安斜坡和饶阳凹陷留楚构造为研究对象,对比了斜坡区和隆起区断裂密集带的特征及其对不同构造部位油气分布的控制作用。在三维地震资料、钻井资料和已发现油气藏特征的基础上,利用断裂密集带识别方法和分类方案,识别出文安斜坡和留楚构造的断裂密集带,并对其进行了分类。对比两种构造部位断裂密集带发育的差异性及对油气分布的控制作用,认为隆起区(留楚构造)相对于斜坡区(文安斜坡)断裂密集带发育数量较少,规模大,斜坡区断裂密集带主要以顺向背形断裂密集带为主,而隆起区主要以屋脊背形断裂密集带为主,隆起区油气主要分布在顺向背形断裂密集带内,斜坡区主要分布在屋脊背形断裂密集带内部及靠近生烃中心的边部。 相似文献
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796.
Jan Deprest Marie-Paule Emonds Jute Richter Philip DeKoninck Tim Van Mieghem Dominique Van Schoubroeck Roland Devlieger Luc De Catte Liesbeth Lewi 《黑龙江环境通报》2011,31(7):661-666
With the increased use of invasive fetal procedures, the number of women facing post-procedure membrane rupture is increasing. Here we review the use of platelets and fresh frozen plasma for sealing iatrogenic fetal membrane defects by describing the mechanisms of action of the amniopatch procedure as well as published experience. In cases of iatrogenic preterm pre-labour rupture of the membranes, amniopatch effectively seals the fetal membranes in over two-thirds of cases. There is a risk of 16% of in utero fetal death, which may occur at varying intervals from the procedure and often for unknown reasons. Amniopatch has also been used as a treatment of chorionic membrane separation. In summary, current experience suggests that in cases of early onset but persistent amniotic fluid leakage following an invasive fetal procedure, amniopatch is an option. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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799.
Large-scale patterns of shell variation in Littorina striata, a planktonic developing periwinkle from Macaronesia (Mollusca: Prosobranchia) 总被引:2,自引:1,他引:1
Littorina striata King and Broderip, 1832 is a strictly Macaronesian, intertidal periwinkle with planktonic development. The species displays
a high degree of shell variation involving size and sculpture (nodulose vs smooth shells). The present work provides a preliminary
account of some aspects of this shell variation on wave-exposed shores over the entire geographical range of the species.
Based on morphological patterns observed among other prosobranchs it was predicted that southern specimens of L. littorina should on the average be larger, heavier, more nodulose, and should show more shell repair marks, than northern specimens.
These expectations were confirmed for shell size and weight. In contrast, there was no consistent pattern in nodulosity between
archipelagos, even though there were differences at much smaller scales. Shell repair marks were more prevalent in northern
populations, but this trend was only due to a significant N–S difference among nodulose shells. This is surprising as nodulose
shells displayed significantly fewer shell repair marks than smooth shells. These observations were tentatively interpreted
as a function of presumed differential N–S patterns of wave action and ambient temperatures. In this context, wave action
in Macaronesia seems to increase in the south (contrary to what current theories predict). This atypical situation may confound
the interpretation of morphological patterns in L. striata so that firm conclusions cannot be drawn without further experimental work at different spatial scales. Nevertheless, it
seems that generalisations about macrogeographic shell morphology patterns, based on interspecific comparisons, are not directly
applicable to intraspecific patterns, and may strongly depend on local conditions which make adequate sampling and data treatment
very difficult.
Received: 10 September 1997 / Accepted: 15 January 1998 相似文献
800.
A. C. Engels L. Joyeux C. Brantner B. De Keersmaecker L. De Catte D. Baud J. Deprest T. Van Mieghem 《黑龙江环境通报》2016,36(3):266-273
The fetal central nervous system can already be examined in the first trimester of pregnancy. Acrania, alobar holoprosencephaly, cephaloceles, and spina bifida can confidently be diagnosed at that stage and should actively be looked for in every fetus undergoing first-trimester ultrasound. For some other conditions, such as vermian anomalies and agenesis of the corpus callosum, markers have been identified, but the diagnosis can only be confirmed in the second trimester of gestation. For these conditions, data on sensitivity and more importantly specificity and false positives are lacking, and one should therefore be aware not to falsely reassure or scare expecting parents based on first-trimester findings. This review summarizes the current knowledge of first-trimester neurosonography in the normal and abnormal fetus and gives an overview of which diseases can be diagnosed. © 2016 John Wiley & Sons, Ltd. 相似文献