排序方式: 共有8条查询结果,搜索用时 677 毫秒
1
1.
2.
3.
4.
5.
A case of prenatal diagnosis of an overgrowth syndrome at 30 weeks of gestation is reported. The diagnosis was suggested on the basis of increased fetal growth from 16 weeks onwards, advanced bone age, and characteristic facial features such as hypertelorism, broad forehead and small chin. The fetus presented at 12 weeks with a markedly increased nuchal translucency thickness and generalized skin edema, but normal karyotype. Serial ultrasound scans revealed brain abnormalities including mild unilateral ventriculomegaly and a cyst in the cavum septi pellucidi. The pregnancy was terminated at the parents' request at 32 weeks of gestation and postmortem examination confirmed the prenatal findings. This case demonstrates the possibility of prenatal diagnosis of early overgrowth syndromes and highlights the dilemma arising from the prenatal diagnosis of a non-lethal condition associated with an uncertain prognosis and poorly documented in utero. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
6.
Schw 《Die Naturwissenschaften》1988,75(9):478-478
Naturwissenschaften Aktuell
Personalstellen für Forschung und Lehre stagnieren 相似文献7.
Heidelore Fiedler Gerd Rippen Susanne Sievers Peter Friesel Birgit Gras Christoph Lau Thomas Reich Uwe Schacht Roland Schwörer Hansjörg F. Wesp Otto Hutzinger Fritz Vahrenholt 《Environmental Sciences Europe》1997,9(3):131-135
The sources and reservoirs of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) in the city of Hamburg, Germany, in the year 1992 were identified and quantified combining analytical data of PCDD/PCDF with statistical data on annual fluxes of materials and products. Fluxes and amounts of PCDD/PCDF were estimated for the environmental compartments water, air, and soil. Dioxin emissions originating from industrial, commercial or private activities were also calculated. Together with the analysis of the specific regional nutrition data, the human exposurevia the various pathways could be determined. It could be shown that the total PCDD/PCDF intake of individuals in Hamburg was about the same as the national average. High annual fluxes of PCDD/PCDF connected with the trade of industrial products and the waste management and disposal: system in Hamburg obviously had no influence on the human intake of PCDD/PCDF. 相似文献
8.
A computational model to predict acute aquatic toxicity to the ciliate Tetrahymena pyriformis has been developed. A general prediction of toxicity can be based on three consecutive steps: 1. Identification of a potential reactive mechanism via structural alerts; 2. Confirmation and quantification of (bio)chemical reactivity; 3. Establishing a relationship between calculated reactivity and toxicity. The method described herein uses a combination of a reactive toxicity (RT) model, including computed kinetic rate constants for adduct formation (log k) via a Michael acceptor mechanism of action, and baseline toxicity (BT), modelled by hydrophobicity (octanol-water partition coefficient). The maximum of the RT and BT values defines acute toxicity for a particular compound. The reactive toxicity model is based on site-specific steric and quantum chemical ground state electronic properties. The performance of the model was examined in terms of predicting the toxicity of 106 potential Michael acceptor compounds covering several classes of compounds (aldehydes, ketones, esters, heterocycles). The advantages of the computational method are described. The method allows for a closer and more transparent mechanistic insight into the molecular initiating events of toxicological endpoints. 相似文献
1