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排序方式: 共有3399条查询结果,搜索用时 31 毫秒
961.
Owen P. Phillips MD Lee P. Shulman Lisa A. Altieri R. Sidney Wilroy Donald S. Emerson John V. Dacus Sherman Elias 《黑龙江环境通报》1991,11(9):705-710
A 21 -year-old woman with progressively deforming or type III osteogenesis imperfecta (OI) presented for prenatal counselling and diagnosis at 10 weeks' gestation. Family history was non-contributory. At 14.8 weeks' gestation, ultrasonographic examination revealed fetal skeletal hypomineralization, easily compressible fetal cranium, and thickened long bones, indicating that the fetus was also affected. Confirmation of the prenatal diagnosis of OI type III was made following a Caesarean section birth of a male infant with multiple skeletal deformities and blue sclerae implying, in this case, autosomal dominant inheritance. 相似文献
962.
针对钻井废水含油量高、化学需氧量高、悬浮物浓度及色度高的特点,综述了化学破乳法在钻井废水处理中的应用,详细阐述了化学法破乳的机理、絮凝剂的种类和性能。并提出絮凝剂逐渐由无机向有机和天然高分子化合物,由单一型向复合型转化的发展方向。 相似文献
963.
高职高专院校公共选修课程体系探究 总被引:2,自引:0,他引:2
针对一些高职高专院校重技能、轻人文而导致公共选修课建设甚至缺失的现象,对公共选修课程体系建构在目标、内容方面作了详细阐述,并对课程类型的设置、开设年级和课时比例设置提出了建议。 相似文献
964.
965.
J. L. M. Keulemans I. Sinigerska V. H. Garritsen J. G. M. Huijmans Y. V. Voznyi O. P. van Diggelen W. J. Kleijer 《黑龙江环境通报》2002,22(11):1016-1021
Prenatal diagnosis of the Hunter syndrome (mucopolysaccharidosis type II; MPS II) is preferably achieved by the assay of iduronate-2-sulphate sulphatase (IDS) in uncultured chorionic villi (CV) as this allows early (12th week), rapid (2–3 days) and reliable results. We summarize the results of 174 prenatal analyses in the past 30 years, using various methods such as radiolabelled sulphate incorporation in amniotic fluid (AF) cells, glycosaminoglycan (GAG)-electrophoresis in AF and IDS assay in CV, CV-cells, AF and AF-cells. Twenty-seven fetuses with MPS II were diagnosed after finding clearly abnormal results in pregnancies with a male fetus; very low IDS activity has also been measured in some pregnancies with a (heterozygous) female fetus, emphasizing the need to combine enzyme assay with fetal sex determination. IDS activity has until recently been assessed by a cumbersome radioactive enzyme assay. Here we describe the use of a novel fluorigenic 4-methylumbelliferyl substrate, which allows a sensitive, rapid and convenient assay of IDS activity and reliable early prenatal diagnosis. This novel IDS assay was validated in retrospective analyses of 14 CV, CV-cell, AF and AF-cell samples from affected pregnancies in addition to prospective prenatal diagnosis in eight pregnancies at risk with one MPS II-affected fetus. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
966.
Toru Sakuma Naruji Sugiyama Takashi Ichiki Masanori Kobayashi Yoshiro Wada Daisuke Nohara 《黑龙江环境通报》1991,11(2):77-82
The urinary acylcarnitine profiles of two mothers whose first children were diagnosed to have glutaric aciduria type 2 (multiple acyl-CoA dehydrogenation deficiency, electron transfer flavoprotein (ETF) deficiency) were analysed in the second pregnancy. Large volumes of tigrylcarnitine and isovalerylcarnitine and a little glutarylcarnitine were detected. Each fetus was also diagnosed to be abnormal by enzyme activity and immunoassay of ETF protein. The acylcarnitines in the mothers' urine disappeared in 1 week after labour or artificial abortion. Acylcarnitines were never detected in the urine of controls. 相似文献
967.
Luna EM 《Disasters》2001,25(3):216-226
The Philippines is very vulnerable to natural disasters because of its natural setting, as well as its socio-economic, political and environmental context--especially its widespread poverty. The Philippines has a well-established institutional and legal framework for disaster management, including built-in mechanisms for participation of the people and NGOs in decision-making and programme implementation. The nature and extent of collaboration with government in disaster preparedness and mitigation issues varies greatly according to their roots, either in past confrontation and political struggles or traditional charity activities. The growing NGO involvement in disaster management has been influenced by this history. Some agencies work well with local government and there is an increasing trend for collaborative work in disaster mitigation and preparedness. Some NGOs, however, retain critical positions. These organisations tend to engage more in advocacy and legal support for communities facing increased risk because of development projects and environmental destruction. Entry points into disaster mitigation and preparedness vary as well. Development-oriented agencies are drawn into these issues when the community members with whom they work face disaster. Relief organisations, too, realise the need for community mobilisation, and are thus drawn towards development roles. 相似文献
968.
Many marshes in the Gulf Coast Chenier Plain, USA, are managed through a combination of fall or winter burning and structural
marsh management (i.e., levees and water control structures; hereafter SMM). The goals of winter burning and SMM include improvement
of waterfowl and furbearer habitat, maintenance of historic isohaline lines, and creation and maintenance of emergent wetlands.
Although management practices are intended to influence the plant community, effects of these practices on primary productivity
have not been investigated. Marsh processes, such as vertical accretion and nutrient cycles, which depend on primary productivity
may be affected directly or indirectly by winter burning or SMM. We compared Chenier Plain plant community characteristics
(species composition and above- and belowground biomass) in experimentally burned and unburned control plots within impounded
and unimpounded marshes at 7 months (1996), 19 months (1997), and 31 months (1998) after burning. Burning and SMM did not
affect number of plant species or species composition in our experiment. For all three years combined, burned plots had higher
live above-ground biomass than did unburned plots. Total above-ground and dead above-ground biomasses were reduced in burned
plots for two and three years, respectively, compared to those in unburned control plots. During all three years, belowground
biomass was lower in impounded than in unimpounded marshes but did not differ between burn treatments. Our results clearly
indicate that current marsh management practices influence marsh primary productivity and may impact other marsh processes,
such as vertical accretion, that are dependent on organic matter accumulation and decay. 相似文献
969.
The aim of this study is to investigate conversion of nitrogen and COD in enriched paddy soil by nitrification coupled with anammox process in a dual chamber bioelectrochemical system. The paddy soil was enriched for denitrification coupled with anammox by microbial consortia and was acclimatized in the cathodic chamber of microbial fuel cells(MFCs). The bioelectrochemical systems were treated with different ammonium concentrations in the cathodic chamber: the MFC with low concentration ammonium... 相似文献
970.