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51.
David L. Skidmore Aditya P. Pai Ants Toi Leslie Steele David Chitayat 《黑龙江环境通报》2003,23(12):1009-1013
Two de novo cases with Apert Syndrome detected prenatally are presented herein. In the first, fetal ultrasound findings of syndactyly of the hands, craniosynostosis and proptosis resulted in a prenatal diagnosis in the nineteenth week of gestation. This is the earliest prenatal diagnosis of this syndrome in a not-at-risk case. Following counseling, this pregnancy was terminated and subsequent pathological examination and DNA analysis confirmed the diagnosis of Apert Syndrome and coarctation of the aorta. In the second case, fetal ultrasound at 21 weeks' gestation revealed a hypoplastic left heart and clover-leaf skull. Following counseling, this pregnancy was also terminated. Further examination of the fetus and DNA analysis led to a diagnosis of Apert Syndrome. These cases emphasize the need to complete a thorough fetal ultrasound in cases with potentially lethal cardiac abnormality and the importance of incorporating a fetal pathologist, as well as a medical geneticist, in the investigations performed after delivery or pregnancy termination when a fetal abnormality is detected on ultrasound. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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53.
Jun Murotsuki MD Shigeki Uehara Kunihiro Okamura Akira Yajima Kazuhiro Murakami 《黑龙江环境通报》1994,14(7):637-639
A case of type III congenital cystic adenomatoid malformation of the lung was successfully diagnosed prenatally by fetal lung biopsy. We performed this procedure at 22 weeks of gestation, using a biopsy gun system under ultrasound guidance. The pregnancy was undisturbed by the procedure but as the condition was incompatible with life, an abortion was performed. The diagnosis was confirmed at post-mortem examination. Fetal lung biopsy appears to be a useful method for prenatal diagnosis of fetal lung disorders. 相似文献
54.
氢氟酸的污染与防治 总被引:1,自引:0,他引:1
方慧萍 《石油化工环境保护》1997,(1):52-54
综述氢氟酸烷基化装置,运行过程中氢氟酸的危害,污染源的分析,防治措施及取得效果. 相似文献
55.
56.
岷江上游崩塌滑坡分布规律研究 总被引:1,自引:0,他引:1
乔建平 《长江流域资源与环境》1994,3(4):365-370
岷江为长江—级支流,上游长330km,自1986年以来,发生崩塌滑坡200余处,体积约2.1亿m ̄3。作者研究了岷江上游崩塌滑坡的分布规律。采用统计指标法,将岷江上游分为三种不同的崩塌滑坡分布密度区:①UXS.高密度区;②MXS,中密度区;③LXS_3低密度区。 相似文献
57.
三峡工程与长江中游沿江产业带建设 总被引:3,自引:0,他引:3
讨论了长江中游沿江产业带发展条件、限制因素和未来发展,指出三峡工程的建设将对长江中游产业的布局和经济发展带来深刻的变化;防洪作用促进中游两岸大型工业项目的兴建,调整现有沿江城镇的布局,使之结构趋于合理化;电力供应经解能源的紧张状态,改善航运条件,发挥长江黄金水道的综合效益。当然,由于坝下河道冲刷,对现有的码头带来一定的影响,由于冬季水位抬升引起两岸低湖田地下水位上升,加剧两岸土壤潜育化和沼泽化。 相似文献
58.
Data on the existence of a specific system regulating the growth, size, and structure of enterobacterial populations are first summarized in terms of the chemical ecology concept formulated by S.S. Shvarts. The role of this system in transgene functioning is described using the example of the lux operon integrated into Escherichia coli. A relatively simple test for estimating such interactions is proposed.Translated from Ekologiya, No. 2, 2005, pp. 91–96.Original Russian Text Copyright © 2005 by Pshenichnov, Maslennikova, Nikitina. 相似文献
59.
修文群 《中国人口.资源与环境》2005,15(2):122-126
面对当前我国经济开发区发展所面临的主要挑战,无论从自身经济增长规律出发.还是应对外部竞争压力,在新形势下,信息化是实现开发区产业升级与可持续发展的必由之路。如何针对开发区实际状况,系统、科学地进行信息化建设,包括大力发展信息产业并使其成为支柱产业,开创新经济增长点;以信息技术改造传统产业,促进产业升级与结构调整;以电子政务提高政府管理水平与服务效率、以电子商务提高企业的经营绩效与创新能力;以信息化推动城市化进程,提高人口素质与生活水平等。针对上述议题,特提出以“数字城市”建设、完善信息产业链为核心的开发区信息化发展战略。 相似文献
60.
Mfon T.Udo 《环境科学学报(英文版)》2002,14(4)
Aspects of the trophic attributes of the mudskipper,Periophthalmus barbarus occurring in the mangrove swamps of ImoRiver estuary, Nigeria, were investigated during a 12-month period(April, 1992-March, 1993). Feeding intensity increased with size;it was higher in the dry season (November-April) than in the wetseason (May-October); monthly changes in the indices of feedingintensity were significantly correlated. Major food objectscomprised detritus and benthic algae; crustaceans, insects,macrophyte matter and sand grains were minor food objects whilefish, molluscs, Chilopoda, nematodes and fungi were unconsciouslydevoured objects. Diet varied seasonally; algae and sesarmid crabswere generally more in the dry season than during the rains whereasFPOM and fish increased in the wet over dry season. The mudskipperdisplay a high degree of euryphagy and can be considered as ageneralist and an omnivore. The lower trophic status of P. barbarusqualifies it as a good aquaculture candidate. Food richness washigher in big-sized class (BSC) than small-sized class (SSC).Size-based and seasonal variations were not apparent in foodrichness. Diet breadth was higher in the BSC than the SSC; therewas dry season increase in diet breadth. 相似文献