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231.
Autosomal recessive polycystic kidney disease (ARPKD) is a rare hereditary disease with a high neonatal mortality. Currently, prenatal diagnosis is possible only during the second half of pregnancy, when bilaterally enlarged, echogenic kidneys are visible by ultrasound. We describe a case in which a diagnosis of ARPKD was sought in the first half of pregnancy. High-resolution ultrasonography revealed echogenic, normal-sized kidneys at 15+4 weeks. Microsatellite DNA analysis of a chorionic villus sample, parental blood, and blood of an affected sibling showed that the fetus had the maternal haplotype and a recombination of the paternal haplotype. Thus, no distinction between homo- and heterozygosity for the ARPKD mutation in the fetus was possible. A further ultrasound examination at 19+4 weeks confirmed the previous results, indicating that the fetus was likely to be affected. After termination of the pregnancy, the diagnosis was confirmed on microscopic examination.  相似文献   
232.
IntroductionRecently,theindustrialtextilewastewaterhasbeenconsideredtobeaseriouspollutionproblemthroughouttheworld.About10000dif?..  相似文献   
233.
糯稻和非糯稻蜡质基因的新STS分子标记   总被引:3,自引:0,他引:3  
通过对前人公布的糯性水稻蜡质基因全序列测定结果的分析,根据糯性水稻与非糯性水稻蜡质基因序列位点的差异,设计了两个基于PCR扩增反应的可特异识别糯性水稻的显性和共显性STS分子标记;同时在前人公布的非糯性水稻蜡质基因的不同类型(Wxa和Wxb)的全序列比对分析的基础上,选取了两种基因型特定的差异位点,设计了两个基于PCR扩增反应用于特异识别这两种Wx基因的显性STS分子标记,并用新建立的标记对相应的水稻基因型进行了检测.图2表2参10  相似文献   
234.
介绍了UG/OpenAPI的基本概念和特点,研究了标题栏和明细表自动生成的一些关键技术和方法。并用VC++6.0编制出标题栏和明细表自动生成程序,弥补了UG的不足。  相似文献   
235.
Prenatal diagnosis, by amniocentesis, revealed mosaicism with respect to a bisatellited, apparently dicentric, DA/DAPI positive, de novo marker. The following cell lines were observed in decreasing order of frequency: 46,XX > 48.XX, + mar, + mar » 47,XX, + mar. The pregnancy was terminated and post-mortem examination revealed an apparently normal fetus. Cytogenetic studies of fetal and placental tissues revealed approximately the same level of mosaicism together with the unusual copy number ratio seen in the amniotic fluid cultures. Non-disjunction at the first post-zygotic mitotic division giving rise to a mosaic: 46,XX/ 48,XX, + mar, + mar followed by subsequent mitotic instability of the marker could account for the unusual copy number ratio.  相似文献   
236.
《石油化工企业设计防火规范》和储罐消防喷淋设计的角度计算北山岭原油罐区消防用水总量、系统储水能力和储罐消防冷却喷淋强度,分析罐区目前消防储水系统的可靠性。  相似文献   
237.
IntroductionPlantstrawasaimportantmeasureforincreasingthefertilityandimprovingthestructureofsoil,hasbeenwidelyappliedinagricu?..  相似文献   
238.
ABSTRACT: Water resources professionals should be engaged actively in revisiting state water rights law. During the past four years, sponsored by the American Society of Civil Engineers with cooperation of other water resources organizations, over a hundred engineers, hydrologists, geographers, lawyers, administrators, educators, water users, and other persons interested in water law have been preparing a Model State Water Rights Code. Preliminary drafts of the Model Code have been considered in four states, and its provisions will be disseminated nationally to state legislators and other policy makers upon formal publication in September 1994. The Model Code gathers the best provisions from state water laws into comprehensive regulated riparian and prior appropriation provisions, includes commentaries explaining how its textual sections address water resources planning and management issues, and references similar language in current state water statutes. The goal of the Code Project is to provide materials which will assist legislators so they can enact effective, efficient, and equitable water laws. In the future, the Code drafting group will expand its efforts to develop legal guidelines for allocating shared transboundary water resources, water quality law, federal water statutes, and other water resources legal issues.  相似文献   
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