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721.
We describe our experiences of prenatal diagnosis of alpha-1-antitrypsin deficiency using closely linked polymorphisms detected by Southern blotting and the polymerase chain reaction. Prenatal diagnosis was carried out for 17 pregnancies from 15 couples. 相似文献
722.
IntroductionArhaReservoirislocatedintheplateauregionofSouthwestChina.Thisreservoir,withavolumeof445millionm3,wasbuiltin1960andisth?.. 相似文献
723.
Human pregnancy-specific β-1-glycoprotein (SP1) was assayed retrospectively in stored maternal serum (MS) samples from 82 chromosomally abnormal pregnancies and 377 matched controls. The median MSSP1 concentration in 48 Down's syndrome pregnancies was significantly elevated at 1.17 multiples of the control median (MOM), and significantly reduced (0.5 MOM) in a group of eight cases of unbalanced translocations. There was no significant difference in median SP1 concentrations in cases of trisomy 18, trisomy 13, balanced translocations, or sex chromosome abnormalities. A comparison with human chorionic gonadotrophin results in the same series of samples indicates that SP1 is a less sensitive predictor of Down's syndrome pregnancies. 相似文献
724.
We describe further development of the fumarylacetoacetase (FAA) assay for the prenatal diagnosis of tyrosinaemia type 1 using chorionic villus sampling (CVS). We have established a reference range for FAA activity in cultured villus cells and have confirmed previously reported data on the FAA activity in uncultured chorionic villus cells. This should allow confirmation of results using CVS, without the need for further invasive procedures. We report the FAA enzyme stability at −70°C, +4°C, and at room temperature, and we have shown no obvious difference in enzyme activity with gestational age. We have analysed cultured and non-cultured CVS activity of FAA in two pregnancies at risk of tyrosinaemia type 1. In both, the fetus was designated unaffected, and these results were confirmed postnatally. 相似文献
725.
带有残差修正的GIM(1)模型在工业固体废弃物排放量预测中的应用 总被引:1,自引:0,他引:1
基于灰色系统理论,研究和提出了带有残差修正的GIM(1)模型,并给出了估计这种模型参数的简捷方法.实例表明,运用该方法得到的模型具有优良的预测精度,从而扩大了灰色预测方法在环境系统中的应用范围. 相似文献
726.
G. Corney D. B. Whitehouse D. A. Hopkinson C. H. Rodeck K. Nicolaides M. Norman A. P. Mowat 《黑龙江环境通报》1987,7(2):101-108
Fetal blood sampling for the diagnosis of alpha-1-antitrypsin deficiency using protein isoelectric focusing was carried out in the period 1980–1985. The results of 25 cases from 18 mothers are reported. All had a previous history of a PiZ child affected by liver disease. The method was found to be technically satisfactory and the fetal results were subsequently confirmed in all 18 cases where follow-up was possible. The fetus was found to be PiZ in nine cases and all these pregnancies were terminated. Of the remaining pregnancies three cases aborted or were delivered prematurely and 13 proceeded to term without complications. 相似文献
727.
728.
主要介绍了地震数据断记报警软件及其相关地震数据分类处理软件,此软件一方面保证了地震监测数据的连续性,另一方面使科研人员查询地震事件波形,迅速快捷,并可对典型地震事件和震相特征进行查看,提高对一些特殊地震震相的识别,从而也提高了地震的分析水平. 相似文献
729.
Stepnowski P Storoniak P 《Environmental science and pollution research international》2005,12(4):199-204
- Aims and Background. Ionic liquid application in industry will offer several excellent solutions, but it also means that they
will enter the environment sooner or later. Responsible product design should always take into consideration not only technological
demands, but also the risks arising out of possible toxicity and ecotoxicity. In our strategy we are aiming to understand
the fate of these entities through their life cycle in the environment as a complimentary element of their design. This paper
presents results on the lipophilicity of selected imidazolium ionic liquids, a parameter that plays a key role in environmental
and biological distribution. Additionally, the prediction of the most stable metabolite of a 1-butyl-3-methylimidazolium (BMIM)
cation – a congener representative of this group of compounds is presented.
Materials and Methods Lipophilicity was evaluated by means of reversed phase and immobilized artificial membrane chromatography and further compared
to calculated data. Theoretical prediction of lipophilicity was undertaken using fragmental methodology combined with manual
calculations of the geometric bond factor for quaternary ammonium and the electronic bond factor due to the presence of a
charge.
Results and Discussion All the substances studied are characterized by very low partition coefficients, and lipophilicity varies linearly with elongation
of the n-alkyl chain. Prediction of metabolic routes was based solely on thermodynamic data of the radical intermediates formed
during the reaction with the cytochrome P450 system. The energetically most stable radical structure is generated by hydrogen
abstraction from the gamma position of the BMIM cation.
Conclusions and Recommendations. The experimentally measured and theoretically estimated lipophilicity coefficients obtained for all the
compounds studied generally indicate a relatively low lipophilicity and thus preferable partition to the aqueous phase. By
means of thermodynamic data, it was also confirmed that the energetically most stable radical structure is generated by hydrogen
abstraction from the gamma position on the alkyl chain in the 1-alkyl-3-methylimidazolium cation, as a result of which the
C1 atom is preferentially oxidized.
- * The basis of this peer-reviewed paper is a presentation at the 9th FECS Conference on 'Chemistry and Environment', 29 August
to 1 September 2004, Bordeaux, France. 相似文献
730.