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991.
992.
Deficiency of amylo-1,6–glucosidase activity was expressed in parallel in liver and skin fibroblasts from a patient with type III glycogenosis. In crude extracts of control liver and muscle, amylo-1, 6–glucosidase (M.W. 164000) was identified by immunoprecipitation; no cross-reacting material was found in the patient's liver. Assay of amylo-1,6–glucosidase activity in cultured skin fibroblasts from the affected family revealed less than 10 per cent of control value in mutant homozygous cells whereas in cells from the parents, activity was reduced to 40–60 per cent of the control value. Activity in cultured amniotic fluid cells was similar to that of control fibroblasts. In cultured amniotic fluid cells obtained during the mother's subsequent pregnancy, the normal amylo–1,6–glucosidase activity measured, predicted correctly the outcome of this pregnancy prior to the 20th week of gestation. 相似文献
993.
排污权交易的经济优化机制研究 总被引:6,自引:0,他引:6
利用经济学原理,分析了环境污染产生的原因和经济学对策,对排污权交易理论和市场优化机制进行了研究,并说明我国建立排污权交易市场的可行性。 相似文献
994.
静电除尘声波清灰原理及设计要点 总被引:2,自引:0,他引:2
本文介绍了静电除尘器声波清灰的特点 ,声波清灰原理、声波发生器性能以及静电除尘器声波清灰设计要点。 相似文献
995.
铁屑—粉煤灰处理含铬电镀废水的探讨 总被引:9,自引:0,他引:9
根据腐蚀电池原理,用铁屑-铁煤灰处理电镀含铬废水,结果表明,Cr(Ⅵ)去除率达到98%处理后出水水质良好,水质符合排放标准要求。 相似文献
996.
Preparation of TiO2-MoO3 nano-composite photo-catalyst by supercritical fluid dry method 总被引:3,自引:0,他引:3
IntroductionTiO2 iswidelyusedinmultiphasephoto catalyticreactions ,andisalsooneofthemosteffectivecatalystsinthedegradationofenvironmentalcontaminants (Hoffmann ,1995 ;Fujishima ,2 0 0 0 ) .However,asasemiconductorofwidebandgap ,itcouldonlybeactivatedbyult… 相似文献
997.
A child was tentatively diagnosed as having cystic fibrosis, based on neonatal presentation with severe gastrointestinal complications; the diagnosis was not confirmed biochemically and no tissues were available for DNA analysis. The mother presented in her subsequent pregnancy, and microvillar enzyme analysis of cell-free amniotic fluid at both 18 and 20 weeks gestation gave equivocal results. The pregnancy was terminated voluntarily because of a trend towards abnormal enzyme assay results on the second amniocentesis. Retrospectively, fetal tissues were found to be homozygous for the most common mutation of the cystic fibrosis gene (AF508), which confirmed the prenatal assessment and suggested that the first infant of the couple was probably also affected by the disease. 相似文献
998.
R. H. Lindenbaum M. Ryynänen M. Holmes-Siedle E. Puhakainen J. Jonasson J. Keenan 《黑龙江环境通报》1987,7(7):511-519
Maternal serum and amniotic fluid alpha-fetoprotein levels were studied retrospectively in a total of 58 pregnancies with trisomy 18. In those pregnancies uncomplicated by either fetal exomphalos or neural tube defect the midtrimester maternal serum alpha-fetoprotein (MSAFP) levels were markedly reduced, the median value for 38 such pregnancies being 0.6 multiples of the median (MoM). Trisomy 18 with exomphalos was associated with a higher median MSAFP, but still within the normal range: 1.1 MoM, (nine pregnancies); trisomy 18 with exomphalos and neural tube defect (NTD) was associated with grossly raised levels: median MSAFP was 4-5 MoM (three pregnancies). Amniotic fluid alpha-fetoprotein (AFAFP) levels were normal in uncomplicated trisomy 18 pregnancies: median AFAFP, for 19 pregnancies, was 1.1 MoM. Exomphalos alone, or together with neural tube defect, was associated with greatly elevated levels of AFAFP; for exomphalos alone median AFAFP was 9.59 MoM (four pregnancies), and for exomphalos with neural tube defect the median AFAFP was 23.95 Mom (three pregnancies). Screening with low and high MSAFP, routine ultrasound, and amniocentesis on all women aged 35 years or over, together might identify over 50 per cent of pregnancies with trisomy 18. 相似文献
999.
磁流体处理印染废水初探 总被引:3,自引:0,他引:3
探讨了Fe3O4磁流体在不同条件下对降低印染废水的COD和色度两个方面的影响,实验表明,当pH=11,十二烷基叔胺的量是亚铁量的0.16倍时,COD降低最多,脱色效果最好,且磁场强度在160mT左右时,磁流体沉降最快。 相似文献
1000.
Estimation of critical submergence for an intake in a stratified fluid media by neuro-fuzzy approach
Most of the large surface reservoirs are stably stratified throughout most or all of the year. One means of assisting in the management is to allow for the selective withdrawal from the reservoir. The value of the intake’s submergence when the upper layer fluids begin to be drawn into the intake is known as “critical submergence”. In this study, the critical submergence for a circular intake pipe in a stratified body is investigated. Experiments were conducted on a vertically flowing downward intake pipe in a still-water reservoir. Experimental results are compared with that of the neuro-fuzzy models. 相似文献