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771.
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
772.
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
773.
774.
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
775.
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
776.
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
777.
IntroductionInrecentyears,remediationofpetroleumcontaminatedgroundwaterandsoilhasattractedmuchattentionofscientistsinvariousc?.. 相似文献
778.
IntroductionThefrequencyofaccidentaloilspills,andtheassociatedaquaticpollution,aregrowingconcerns.Thereisaneedformodelsystemth?.. 相似文献
779.
煤燃烧中硅酸盐A的高温固硫促进作用 总被引:1,自引:0,他引:1
研究了硅酸盐A在不同含量,不同温度下的对碳酸钙固硫碱性能的影响,发现在1200℃高温下,碳酸钙固硫剂中添加一定量的硅酸盐A,固硫率从16%提高到33%,提高率达106%,若添加碳酸钾与硅酸盐A的复合添加剂,则固硫率为36%,提高率为125%,用含硅酸盐A的钙基固硫剂与煤制成型煤,在实际锅炉中于1250℃试烧,其固硫率达47%。 相似文献
780.
E. Von Lennep N. El Khazen G. De Pierreux J. J. Amy F. Rodesch N. Van Regemorter 《黑龙江环境通报》1985,5(1):35-40
Prenatal echographical findings of a partial sirenomelic fetus are described. An attempt was made to terminate pregnancy by administration of prostaglandin F2a, but uterine rupture occurred. The teratogenic role of vitamin A ingested by the mother in the penconceptional period is discussed. 相似文献