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Farideh Z. Bischoff PhD Dorothy E. Lewis Joe Leigh Simpson Dianne D. Nguyen Jeffrey Scott Wendy Schober Sarah Murrell Sherman Elias 《黑龙江环境通报》1995,15(12):1182-1184
Recovering and analysing fetal erythrocytes from maternal blood is being pursued for non-invasive prenatal genetic diagnosis. We report the observation of 46, XY/47, XXY mosaicism in fetal cells from a woman whose first-trimester chorionic villus sampling (CVS) initially showed only 46, XY. Only after exhaustive (500 cells) analysis were four XXY cells found in cultured villi. 相似文献
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The nature of the cosmic redshift is one of the most fundamental questions in modern science. Hubble's discovery of the apparent Expansion of the Universe is derived from observations on a small number of galaxies at very low redshifts. Today, quasar redshifts have a range more than 1000 times greater than those in Hubble's sample, and represent more than 100 times as many objects. A recent comprehensive compilation of published measurements provides the basis for a study indicating that quasar observations are not in good agreement with the original predictions of the Expanding Universe theory, but are well fit by the predictions of an alternative theory having fewer adjustable parameters. 相似文献
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Urinary tract anomalies are common. Prenatal diagnosis is important and enables either special obstetric management or termination of pregnancy and probably in the future, intrauterine intervention. Transvaginal sonography (TVS) allows visualization of the normal and anomalous fetal urinary tract at an early stage. One thousand nine hundred and forty women were examined via TVS at an early stage of pregnancy between 10 and 16 weeks from the last menstrual period (LMP) and 35 anomalies (1·8 per cent) were clearly identified: 29 cases of low urinary tract obstruction, 2 cases of multicystic dysplastic kidney, 2 cases of polycystic kidney (infantile type), 1 case of double collecting system, and 1 case of horseshoe kidney. Potter syndrome could be ruled out in three patients who had delivered fetuses suffering from this anomaly in previous pregnancies. The concise and early identification of anomalies makes TVS an important aid in the hands of the obstetrician, ultrasonographer, and neonatologist. 相似文献
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泾县地震台地磁FHD仪器房建设几点体会 总被引:3,自引:0,他引:3
地磁数字化观测室是要求很高的永久性用房,对建筑物磁性水平有严格的规定,在建设中必须把握好每一个细节,建筑物才能满足仪器工作的磁性环境要求.本文结合FHD探头房建设工作中遇到的问题,介绍了在磁性检测工作中的一些经验,有借鉴意义. 相似文献
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ZHANG Tian-zhu 《环境科学学报(英文版)》2001,13(3):346-350
IntroductionCleanerproduction (CP)holdsgreatpromiseasaneffectivestrategyinthefaceofdoublechallengesofenvironmentalprotectionandeconomicdevelopment.In 1993,ademonstrationproject (B 4project) ,designedandexecutedbytheStateEnvironmentalProtectionAdministration (… 相似文献
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Epidemiological survey of 573 families, clinical examination of 2593 persons, and X-ray examination of 1136 persons (in 16 typical endemic villages) were conducted, based on the classification of endemiology for KBD disease areas, i.e, mountain type, loess plateau type, plateau type, and flatlands type. It was revealed that the KBD disease areas exhibited the regular pattern of corming-into-being, development and passing-away and the characteristics of growth and decline. Further, it was found clinically that the disease areas may be divided into 4 types, i.e., recent onset, developing, stable, and historical. This division is simple and easy, practical, scientific, and reliable and can be applied by medical personnel at different levels. 相似文献