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241.
Ellen Sidransky Susan H. Black Dawn M. Soenksen Shirley L. Jones Andrew D. Dorfmann Joseph D. Schulman MD 《黑龙江环境通报》1990,10(9):583-586
Chorionic villus sampling (CVS) with either transcervical catheters or transabdominal needles is a widely-accepted method for prenatal diagnosis. However, there exists a small subset of patients in whom sampling is difficult or impossible with either route because of individual anatomic variations. A new method of chorionic villus biopsy has been developed to circumvent these problems, utilizing transvaginal chorionic needle aspiration guided by an intravaginal ultrasound probe. This technique was performed successfully in 15 patients in whom villi could not be obtained by either of the conventional methods. This method now makes CVS possible in essentially all women regardless of their uterine anatomy or placental placement; it may also prove useful for very early chorionic sampling. 相似文献
242.
This paper reports results of an exploratory study of prenatal diagnosis patients who experienced voluntary terminations of pregnancy following the detection of an abnormality or spontaneous miscarriages. The 121 participants were part of the national collaborative Chorionic Villus Sampling and Amniocentesis Study. They completed semi-structured telephone interviews and mailed questionnaires at 1 month and 6 months after the pregnancy losses. Scores on the Profile of Mood States showed that mood levels improved significantly over time. However, there were some declines in loss-related support from partners and others. The persisting distress and difficulties of a minority highlight the variability in women's responses to pregnancy losses. Women who lost pregnancies later in gestation, showed the greatest mood disturbances at initial assessments, used professional mental health assistance after the loss, or reported less satisfactory loss-related support from significant others showed the greatest levels of mood disturbance at the six-month assessment. Follow-up contacts with patients who lose pregnancies should be used to inform women about the variation in possible grief reactions, to assess the extent of support the women are receiving from their partners and significant others, and to provide additional follow-up or referral of those experiencing the greatest distress. 相似文献
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Prenatal real-time ultrasonographic diagnosis of microphthalmia is presented. Diagnosis was made at 18 weeks' gestation in a fetus of a patient with a previous infant affected with the syndrome of cryptophthalmia with absence of septum nasi and ambiguous genitalia (Fraser syndrome). Recognition of microphthalmia as a part of Fraser syndrome and the easy visualization of fetal facial bones and orbits in the second trimester made the diagnosis possible. 相似文献
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M.Johansson O.W.Heal N.Bayfield O.Brandt R.Brooker M.Forchhammer T.T.Hφye O.Humlum A.J 《Ambio-人类环境杂志》2004,27(Z1):39-49
北大西洋周边区域(SCANNET区域)涵盖了广泛的气候区、自然环境和可用自然资源范围.除了最北部地区,至少自最后一次冰期结束以来,这里就有人和多种文化存在.然而,该区在大的地理尺度上也是非常重要的,因为它影响着全球气候并支撑着在北极地区和世界其它大陆之间迁徙的动物.这一区域的气候、环境和土地利用正在发生急剧变化,预测显示,全球变暖在这里的表现会更强,而土地利用的增加会使剩余的野地急剧减少.因为本区大部分地方人口稀疏(如果有人居住的话),过去环境变化及其影响方面的观测记录也都是很少而且时段很短的.然而,记录现在正在进行的变化、认识这些变化的驱动力和预测这些变化的后果变得非常重要了.为了促进认识全球变化对北大西洋区域陆地的影响的研究,同时也为了实时监测这种变化,2000年欧共体资助成立了一个研究站点网络及其下设机构,命名为SCANNET--斯堪的纳维亚(半岛)(瑞典、挪威、丹麦、冰岛的泛称)/北欧陆地野外基础网络.SCANNET目前包括9个核心站及当地网络里面的5个站,它们一起覆盖了该区当前气候和预测的变化的广泛区域.气候指标在网络内部是共同的,而每个站点都选择特殊的环境和生态主题进行精细观测.这既保证了主题覆盖面的多样性又保证了专门技术的多样性.我们总结了SCANNET到目前为止的发现,并概述其资料基础,以增加对北大西洋环境变化数据的了解.同时我们也总结我们在理解方面的重要缺陷以及SCANNET已经存在机构和行动在促进今后的研究、监测和野外实证行动方面的作用. 相似文献
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Cynthia J. Sims MD Don T. Fujito Dennis R. Burholt Josef Dadok Harlan R. Giles D. Allan Wilkinson 《黑龙江环境通报》1993,13(6):473-480
We have investigated the ability of high-resolution proton NMR spectroscopy to provide a biochemical constituent screening of human amniotic fluid (AF). Proton NMR spectra were obtained at 300 MHz on AF from patients undergoing amniocentesis in the mid-trimester. Only AF from normal pregnancies (normal fetal karyotype, normal a-fetoprotein levels, normal birth outcome) was used in this study. The AF supernatant was lyophilized and resuspended in deuterated water containing 0.1 mm phosphate buffer and 6.02 mm disodium maleate. Identification of low molecular weight compounds was confirmed by two-dimensional NMR spectra (primarily correlated spectroscopy, or COSY) and standard addition techniques. A broad profile of compounds were ‘NMR visible’ in a single proton spectrum, including creatinine, glucose, organic acids (acetate, citrate, and lactate) and several amino acids (alanine, histidine, leucine, phenylalanine, tyrosine and valine). The proton spectrum was unaffected by prior freezing/thawing of AF samples. We were able to quantify compounds by comparison with an added concentration standard (maleate) at concentrations as low as 30 μm. Good agreement with literature values based on other analytical techniques was obtained. 相似文献