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11.
Chih-Ping Chen Schu-Rern Chern Wayseen Wang Chen-Chi Lee Wen-Lin Chen Li-Feng Chen Tung-Yao Chang Chin-Yuan Tzen 《黑龙江环境通报》2001,21(5):346-350
A prenatal diagnosis of partial monosomy 18p(18p11.2→pter) and trisomy 21q(21q22.3→qter) in a fetus with alobar holoprosencephaly (HPE) and premaxillary agenesis (PMA) but without the classical Down syndrome phenotype is reported. A 27-year-old primigravida woman was referred for genetic counselling at 21 weeks' gestation due to sonographic findings of craniofacial abnormalities. Level II ultrasonograms manifested alobar HPE and median orofacial cleft. Cytogenetic analysis and fluorescence in situ hybridization (FISH) on cells obtained from amniocentesis revealed partial monosomy 18p and a cryptic duplication of 21q,46,XY,der(18)t(18;21)(p11.2;q22.3), resulting from a maternal t(18;21) reciprocal translocation. The breakpoints were ascertained by molecular genetic analysis. The pregnancy was terminated. Autopsy showed alobar HPE with PMA, pituitary dysplasia, clinodactyly and classical 18p deletion phenotype but without the presence of major typical phenotypic features of Down syndrome. The phenotype of this antenatally diagnosed case is compared with those observed in six previously reported cases with monosomy 18p due to 18;21 translocation. The present study is the first report of concomitant deletion of HPE critical region of chromosome 18p11.3 and cryptic duplication of a small segment of distal chromosome 21q22.3 outside Down syndrome critical region. The present study shows that cytogenetic analyses are important in detecting chromosomal aberrations in pregnancies with prenatally detected craniofacial abnormalities, and adjunctive molecular investigations are useful in elucidating the genetic pathogenesis of dysmorphism. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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分析简单地拉伸、压缩和扭转的情况时,应力状态能容易地被确定.但是,实际上在金属加工过程中材料是承受复杂的应力状态,在模具——工件接触面上增加有摩擦力.而且,这些应力和摩擦力一般地沿着接触面变化.准确的计算或预测载荷、力、应力和温度,不但对设计适宜的设备是重要的,而且对研究工艺期间材料的变化过程也是重要的.本文将讨论材料变形过程中所运用的主要分析方法及其优缺点. 相似文献
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文章从四个方面阐释学生文化体系的构成,即重在打基础,鼓励学生个性化发展;培植防灾学院自己的学生文化“精英”;创新与创业是学生文化的闪光点;培育一个好的学生文化的管理环境。做到此四点,就可办一个好的、有特点的、合格的高等学校。本文有的放矢,用事实来说话。 相似文献
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Xiao Yali Jiang Dahe Wang Dan 《中国人口.资源与环境(英文版)》2007,5(3):51-56
Urban agglomeration of the Yangtze Delta (UAYD), one of the most developed regions of China, has witnessed an increasing prevalence in building ecological cities when the ecological cities are pursued by many modem cities, and great achievements have been made in this regard. It is inevitable, however, that certain problems exist during the construction of ecological city, which include but not limited to non-harmonious development of urban complex ecosystem, and the difficulty in quantifying eco-city construction or incomplete quantification in assessing the construction of present and future eco-city. Based on the analysis on social-economic conditions and regional conditions of the UAYD, this paper attempts to set up an index system of eco-cities combining with local characteristics, and to adopt the indices of eco-city, urban harmony, and eco-city colligate to evaluate the ecological level, urban harmonious development and eco-city construction of cities within the UAYD. Results indicate that among 15 cities in UAYD, Suzhou City ranks the highest in terms of eco-city construction, whereas Nantong ranks relatively lower; sustainable eco-city construction is possible only when cities are developed in every respect of harmony. 相似文献
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With China's rapid economic growth, ecological construction and environmental protection become increasingly important. The regenerated resources industry is an effective way to solve problems, such as resources depletion, energy shortage, and pollution, and it also has strategic importance for the construction of a resource-conserving and environment-friendly society. The regenerated resources industry has been established in Miluo for long time, which includes a recycling system, a processing and utilization system, and a refuse decontamination system. An industrial cluster is in its early stage of development. In order to solve current problems, such as short industrial chain, low processing rate, and low added value, the industrial cluster should be dynamically upgraded by means of technology innovation, chain nucleus creation, and chain extension. We think the industrial cluster of regenerated resources will become a local brand for Miluo, from which other regions or cities will gain valuable experiences and inspirations. 相似文献
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详细讨论了卫星遥感技术在长江流域水资源管理方面的应用问题,提出了两种实用的方法:①卫星遥感技术在灌溉水资源管理方面的应用;②长江流域地下水、地表水资源估算。进一步分析了两种方法的特点,介绍了卫星遥感技术的优点及用途,建议在长江流域水资源管理中加以利用。 相似文献
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长江中游平原湖区农业开发地域分工与农产品专业化生产研究 总被引:6,自引:1,他引:5
农业生产地域分工与农产品专业化生产是使农业从自然经济阶段向以市场为导向的商品农产品生产转变的一个标志。本文在分析该区农业布局现状及其存在问题的基础上,提出了农业总体布局的设想与不同类型地域农业开发的主攻方向与对策,并对市场经济体制下粮食、棉花、猪、禽、水产品等农产品生产基地的地域选择、建设规模与技术措施等进行了探讨。 相似文献