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621.
Estimation of maternal serum alpha-fetoprotein (AFP) was used as a screening method for the detection of neural tube defects (NTDs) in 6344 women over three years. Of 88 (1.4 per cent) who had one or more serum AFP levels equal to, or greater than, 2.5 multiples of the median (MoM) for the relevant gestational age, 43 (0.68 per cent) underwent amniocentesis. There were eight NTDs. Four of these were screened by serum AFP, and all cases of spina bifida had serum AFP levels greater than 3.0 MoM, including one small open defect which was not seen on ultrasound. The other four cases of NTD, which were not screened, were identified by ultrasound. Of 64 singleton pregnancies 32 (50 per cent) had serum AFP levels between 2.5 and 3.0 MoM, and low birthweight (⪕2500 g) occurred in 29 per cent. Because of improvements in ultrasound techniques and the apparent falling incidence of NTD, the role of serum AFP as the primary screening procedure should be regularly reviewed. Effective screening is dependent on mothers booking early.  相似文献   
622.
Routine ultrasound examination at 30 weeks gestation revealed an intrapulmonary cystic mass in an otherwise normal fetus. Following delivery at term, the diagnosis of congenital cystic adenomatoid malformation of the right lung was confirmed, and an elective right middle lobectomy successfully performed at nine days of age.  相似文献   
623.
In 40 pregnancies at risk for the Hurler syndrome 13 affected fetuses were detected by the demonstration of an α-L -iduronidase deficiency and an increased level of 35S-sulphate incorporation. The diagnoses were confirmed by the analysis of fetal tissues and/or cultured fetal skin fibroblasts. Microassays for α-L -iduronidase, using phenyl α-L -iduronide and more recently 4–methyl-umbelliferyl α-L -iduronide, enabled a reliable diagnosis to be made within 15 to 18 days after amniocentesis. 35S-sulphate incorporation has been a valuable adjunct in cases with a low (heterozygote) enzyme activity.  相似文献   
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固体废物污染防治是“十一五”期间所面临环境保护的重要问题。本文针对固体废物产生及处置利用现状和存在的问题进行了分析,提出了对固体废物污染防治的措施。  相似文献   
630.
Environmental managers at U.S. Department of Defense (DoD) installations overseas are faced with the challenge of managing contaminated sites at these installations with little information on the extent of contamination or the risk posed by the site. In this regard, DoD managers overseas encounter a situation quite similar to the situation faced by decision makers in the U.S. who are managing brownfields. Innovative site characterization and risk-based decision-making methods, which are currently being developed for expeditious application at brownfield sites in the U.S., may also be appropriate for application at overseas DoD sites. In this paper, the analytic hierarchy process (AHP) is used by DoD decision makers to evaluate and rank innovative site characterization technologies and risk-based decision-making and management methods, for use at installations in Korea. Results indicate that for sites with high potential risk the decision makers preferred site characterization technologies that produce data of high quality and a method that can be used to establish credible risk-based remediation goals. This study provides a framework for applying characterization technologies and risk management to poorly characterized contaminated sites in developing countries, where resources for remedial actions may be limited.  相似文献   
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