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The objective of this study was to explore women's attitudes towards prenatal diagnosis of trisomy 21 and to examine some of the factors possibly responsible for these attitudes before implementing in real practice serological screening of pregnant women at risk for trisomy 21. We carried out a telephone survey on a representative sample of women who had recently had a normal livebirth delivery in the Marseille district in 1990. The participation rate was 80 per cent and the average age of the mothers was 28-9 years. Among the 514 women interviewed, 78 per cent stated that they would ask for an amniocentesis for a 1 per cent risk of trisomy 21 at their next pregnancy. When adjusting for confounding factors, the decision to have or not to have an amniocentesis was found to depend not only on the women's attitude towards induced abortion, but also on their understanding of the risk involved and on the social context (knowing a handicapped child, discussion with the father). It also depended on the women's age and on what they knew about amniocentesis from the medical point of view. The risk of miscarriage can influence a woman's choice but this objection was not found to affect the women's decisions significantly in our survey. The data showed the existence of a high potential demand for fetal karyotyping.  相似文献   
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We present a case of fetal abdominal cystic hygroma that presented at 19 weeks of gestation. Ultrasonographic evaluation of the fetus revealed soft tissue enlargement of the left leg and a retroperitoneal mass in the left pelvis and abdomen. This represents the first reported case of prenatal diagnosis of abdominal cystic hygroma.  相似文献   
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To convert gaseous carbonyls to oximes during sampling, an XAD-4 resin denuder system pre-coated with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine and followed by analysis with methane positive chemical ionization gas chromatography/mass spectrometry was used to measure carbonyls in ambient air samples in Riverside, CA. In conjunction with similar analyses of environmental chamber OH radical-initiated reactions of o- and p-xylene, 1,2,4-trimethylbenzene, ethylbenzene, 4-hydroxy-2-butanone and 1,4-butanediol, we identified benzaldehyde, o-, m- and p-tolualdehyde and acetophenone and the dicarbonyls glyoxal, methylglyoxal, biacetyl, ethylglyoxal, 1,4-butenedial, 3-hexene-2,5-dione, 3-oxo-butanal, 1,4-butanedial and malonaldehyde in the ambient air samples. As discussed, these carbonyls and dicarbonyls can be formed from the OH radical-initiated reactions of aromatic hydrocarbons and other volatile organic compounds emitted into the atmosphere, and we conclude that in situ atmospheric formation is a major source of these carbonyls in our Riverside, CA, ambient air samples.  相似文献   
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Environmental site assessment criteria were originally developed by organizations that focused, almost exclusively, on surface, subsurface, and pollution source contamination. Many of the hazards associated with indoor environments and building structures were traditionally not considered when evaluating sources and entities of environmental pollution. Since a large number of building materials are potentially hazardous, careful evaluation is necessary. Until recently, little information on building inspection requirements of environmental problems has been published. Traditionally, asbestos has been the main component of concern. The ever-changing environmental standards have dramatically expanded the scope of building surveys. Indoor environmental concerns, for example, currently include formaldehyde, lead-based paint, polychlorinated biphenyls, radon, and indoor air pollution. Environmental regulations are being expanded and developed that specifically include building structures. These regulatory standards are being triggered by an increased awareness of health effects from indoor exposure, fires, spills, and other accidents that have resulted in injury, death, and financial loss. This article discusses various aspects of assessments for building structures.  相似文献   
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Abstract: For over 10 years, several species of salmon have been identified as either threatened or endangered in the Snake River Basin of Idaho. The United States Bureau of Reclamation, in cooperation with the National Marine Fisheries Service, has proposed a variety of plans to increase stream flows in the Snake River Basin to facilitate movement by juvenile salmon smolts to the ocean. This research examines two of the flow augmentation plans proposed by the Bureau of Reclamation as well as two alternative plans, one founded purely on existing priority‐based water rights and another geared toward minimizing the effects of flow augmentations on farms profitability. Results from a basin‐wide model of agricultural production in the Snake River Basin, the Snake River Agricultural Model, present evidence that (1) older water rights are used towards production of less valuable crops, (2) flow augmentation scenarios have unequal effects on farms profitability across agricultural regions within the basin, and (3) irrigation water is valued from US$4 to US$59 an acre‐foot.  相似文献   
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Two preliminary experiments were performed to explore the use of an intratracheal instillation technique as a cost-effective method of determining the biokinetics of lead (Pb) following respiratory exposure to Pb-contaminated soils. A novel intratracheal instillation procedure was refined and used to deliver a defined dose of Pb-contaminated soil or PbAc to the lower respiratory tract of rats. In the first experiment, rats were sacrificed at numerous time intervals post-dosing, and liver, kidney, blood, and bone tissues were collected for Pb analysis. In the second experiment, rats were dosed with Pb-contaminated soil or PbAc via intratracheal instillation or gastric gavage. All rats were sacrificed 96 h after dose administration and tissues were collected for lead analysis. Data from these experiments indicate Pb is well-absorbed following intratracheal instillation of Pb-contaminated soil, and the intratracheal instillation technique could be used as a cost effective method for exploring the biokinetics of Pb in Pb-contaminated soils following respiratory tract exposure.  相似文献   
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In the and portion of the western U.S., economic development has been affected by the doctrine of appropriative water rights. This paper considers the efficiency aspects of the appropriative doctrine for the case of a stochastic and uncontrolled river, then, subsequently, extends the analysis to the case where the presence of an upstream storage facility provides some degree of flexibility in determining releases. Lastly, the effects of institutions which limit the degree of river use and the implicit release policies attendant are considered.  相似文献   
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