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801.
如何提高处理效果和减少投资,是处理医疗废水的重点.A/O强化二段生物接触氧化 二氧化氯接触消毒工艺综合了厌(兼)氧、好氧以及A-B法的优点,克服了各自的缺点,通过对河南省商丘市第一人民医院的医疗废水处理,证明该工艺是一种处理医疗废水的行之有效的工艺. 相似文献
802.
This study evaluates the adsorption ability ofbisphenol A(BPA) on titanium dioxide(TiO2) and its effect on the photocatalysis by advanced oxidation process using UV radiation and TiO2 photocatalyst. Degradation of BPA was also evaluated for the system without adsorption prior to photocatalytic reaction. The separation of TiO2 from BPA solution treated by pilot-scale photocatalytic reactor (capacity 0.16 m^3) was studied using submerged ultrafiltration (UF) membrane. It was found that although adsorption capacity of BPA was not high, adsorption played an important role in improving the efficiency ofphotocatalysis. On the other hand, during the separation of TiO2 particles from aqueous suspension, the permeate flux of the membrane was strongly affected by transmembrane pressure and TiO2 dose. The permeate turbidity was decreased below 1 NTU. 相似文献
803.
阿拉善地区生物多样性与自然保护区规划 总被引:1,自引:0,他引:1
由于特殊的自然地理条件和独特的地形地貌类型,阿拉善地区具有丰富的珍稀物种资源和多样的生态系统。本文依据保护生物多样性的要求,对该区重点保护区做了具体规划。 相似文献
804.
In our previous work we have isolated fetal cells from maternal blood and used fluorescent in situ hybridization (FISH) for chromosome-specific probes to detect aneuploidy. Current efforts in the Baylor College of Medicine programme are focusing on obtaining consistency in flow-sorting methodology and on determining sensitivity and specificity. To this end, systematic evaluation of five glycophorin A (gly A) antibodies all produced agglutination, leading us to abandon the use of gly A antibodies for positive selection of fetal cells. Conversely, we have found LDS-751 to be useful for nuclear selection. CD45 negative selection can best be accomplished by the use of flasks coated with goat antibodies against mouse antibodies. Positive selection by flow sorting for either CD71+ cells or gamma-globin-positive cells seems to be successful. Using these two approaches, we have recently detected male (fetal) cells in pregnancies in which the fetus was 46, XY in 10 of 18 and in 12 of 14 cases, respectively. 相似文献
805.
806.
Dr. Naomichi Matsumoto Nakamichi Saito Naoki Harada Kiyoji Tanaka Norio Niikawa 《黑龙江环境通报》1995,15(7):675-677
DNA-based prenatal carrier detection of group A xeroderma pigmentosum (XP-A) is reported. Chorionic villus sampling was done at the tenth gestational week in a pregnant woman whose first child suffers from XP-A. Genomic DNAs from the villi, proband, and parents were PCR (polymerase chain reaction)-amplified using three sets of primers, because the PCR and a subsequent enzyme digestion with HphI, AlwNI, or MseI may detect the three most frequent mutations of the XP-A complementing gene (XPAC) in Japanese XP-A patients. The results showed that the proband is a homozygote and that the parents and fetus are heterozygotes for a base substitution at the 3′ acceptor site of intron 3 of XPAC, indicating that the fetus is a healthy carrier of XP-A. This is the first case of prenatal carrier detection of the disorder. 相似文献
807.
织物试样由丙酮-正己烷混合溶剂浸渍后进行超声提取,提取液经Celite层析柱净化。40℃为转蒸发浓缩、定容,由GC/MS测定试样中的DCB、Naphthalene,PCP及Permethrin含量,本方法适合毛织物中防虫蚊整理剂、防霉剂及驱虫制剂残留的定性量分析,方法在目标化合物的检测限(LOQs)D0.1-0.5Mg/Kg之范围内,平均回收率介于89.2-94.6%之间,相对标准偏差为2.3-8.1%。 相似文献
808.
While second-trimester prenatal screening programmes for Down's syndrome have become established in prenatal care, it would be advantageous to be able to offer screening in earlier preganancy. To this end, we have evaluated a new potential maternal serum marker, dimeric inhibin A, as a possible first-trimester marker. Dimeric inhibin A was measured in propsectively collected maternal serum from 23 cases of Down's syndrome and matched chromosomally normal controls, at 11–13 weeks' gestation. Levels of this protein were significantly elevated in the Down's pregnancies compared with the control pregnancies. The median multiple of the normal median (MOM) for the Down's samples was 2.46 (95 per cent confidence interval: 2.11–3.26, P<0.0001 vs. controls). These results suggest that dimeric inhibin A is a useful discriminator of Down's-affected pregnancies from normal pregnancies in the first trimester and that sensitive screening in combination with maternal age and other possible markers may be practicable in the first trimester. 相似文献
809.
IntroductionInrecentyears,remediationofpetroleumcontaminatedgroundwaterandsoilhasattractedmuchattentionofscientistsinvariousc?.. 相似文献
810.
IntroductionThefrequencyofaccidentaloilspills,andtheassociatedaquaticpollution,aregrowingconcerns.Thereisaneedformodelsystemth?.. 相似文献