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621.
Carrie Jones Carol Booth Debra Rita Lydia Jazmines Rhonda Spiro Brian McCulloch Christopher McCaskill Lisa G. Shaffer 《黑龙江环境通报》1995,15(9):843-848
We report a case of maternal uniparental disomy of chromosome 10 discovered after chorionic villus sampling (CVS). Direct preparations revealed mosaic trisomy 10, while cultured CVS cells, as well as amniotic fluid cells, showed only a normal 46,XY complement. DNA analysis using microsatellite markers showed both chromosomes 10 to have been inherited from the mother. The pregnancy was complicated by polyhydramnios. A phenotypically normal male infant of appropriate size was delivered by Caesarean section at 41 weeks' gestation. Since only the direct preparations showed trisomy 10, this case illustrates the importance of CVS direct preparations in the detection of pregnancies at risk of uniparental disomy (UPD). Although the increased frequency of confined placental mosaicism (CPM) diagnosed when direct preparations are performed has been viewed negatively, identification of both CPM and UPD may have biological and clinical significance for a pregnancy. Even though only a single case of maternal disomy 10 is reported here, the apparently normal phenotype provides evidence that there are no major imprinted loci on chromosome 10 that affect in utero growth and development. However, other potential effects such as mental retardation will require long-term follow-up of this as well as additional cases. 相似文献
622.
Effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate 总被引:1,自引:0,他引:1
IntroductionThemolecularstructuresofphenolsshowcharacteristicofhighlyresonance .Sincechlorineisawithdrawingelectronatom ,substitutionofchlorineonaromaticringcancausemanysignificanteffectsonthereactivityofphenols(Folke,1986;Barbeni,1987;Aitken ,1994 ) .Forexample ,… 相似文献
623.
Dr Wiltrud Coerdt Helga Rehder Hans-Jürgen Gebauer Wolfgang Holzgreve Franz Klink Peter Miny Bernt Schulze 《黑龙江环境通报》1988,8(9):647-659
Cardiac defects were studied in five chromosomally abnormal embryos of 10–14 weeks' gestation by free-hand microdissection of hearts measuring 2·5–6 mm in diameter. The type of cardiac malformation alone or in association with other anomalies helped to confirm the chromosome diagnosis established prenatally by chorionic villus sampling or after spontaneous abortion. It was suggestive of a chromosomal disorder in one case in which cytogenetic investigation had failed. 相似文献
624.
625.
For the last 6 years, sonographic signs for excessive fluid accumulation in the backs of 10- to 12-week-old fetuses have been looked for prior to transabdominal chorionic biopsy. In 1400 pregnancies, subsequent karyotype analyses revealed 28 cases of Down syndrome. In 15 ( = 54 per cent), a large fluid cushion over most of the back had been documented at the time of biopsy. Only a few chromosomally normal fetuses with the same peculiarity were observed. The cushion was also present in fetuses with trisomies 18 and 13 , and in Turner syndrome. Systematic first-trimester screening for nuchal fluid accumulation seems to be a recommended method for the detection of Down syndrome and other chromosome anomalies in young pregnant women at low risk. It compares favourably with current methods of maternal serum screening performed at 16–18 weeks which require a higher number of invasive procedures. 相似文献
626.
Our aim was to evaluate the potential value of the ratio of the maternal urinary beta-core fragment of human chorionic gonadotropin (βC-hCG) to creatinine (Cr) in discriminating between normal pregnancies and pregnancies associated with fetal chromosomal abnormalities. We hypothesized that pregnancies with fetal chromosomal abnormalities had abnormal quantities of βC-hCG in the urine. The aims of the present study were to investigate retrospectively whether maternal urinary ratios of βC-hCG/Cr are abnormal in women carrying fetuses with chromosome aberrations and to determine normative median values and a reference range for βC-hCG/Cr between 14 and 19 weeks' gestation. Maternal urinary βC-hCG and Cr concentrations were measured in 150 healthy women from 14 to 19 weeks and compared with ten cases of fetal chromosomal abnormalities matched for gestational age. The preliminary cut-off points corresponded to 0·29 multiple of the normal median (MOM) and 2·83 MOM, which were equivalent to the tenth and 90th centiles of the normal range. Of ten cases of fetal chromosomal abnormalities, one out of one (100 per cent) case with trisomy 18 and three of four (75 per cent) cases of variant 9 chromosome had low βC-hCG/Cr (≤0·29 MOM). One of five (20 per cent) cases with Down syndrome had elevated βC-hCG/Cr (≤2·83 MOM). Urinary βC-hCG/Cr ratios obtained in the second trimester may be useful for improved detection efficiency of Down syndrome, trisomy 18, and inversion of chromosome 9. Second-trimester maternal urinary βC-hCG/Cr should be investigated further as a potential marker for fetal chromosome anomalies. 相似文献
627.
Summary. Geckos consumed immature Bactrocera carambolae males readily, but their consumption was reduced significantly when offered sexually mature males. They showed a similar
aversion for sexually mature males previously fed with methyl eugenol. When male flies at different ages were offered to starved
geckos, geckos’ consumption showed an age-related anti-feeding effect, which was concomitant with the production trend of
6-oxo-1-nonanol, a major endogenous component synthesized in the male rectal gland. The production of 6-oxo-1-nonanol was
also age-related and corresponded with sexual maturity as reported previously. Topical application of the authentic chemical
of 6-oxo-1-nonanol onto the thorax of female fruit flies, at the amount normally detected in the rectal gland of a sexually
mature male, had the same deterrent effect against geckos. 相似文献
628.
Ruurd de Jong Nevile Maher Bruno Patrian Erich St?dler Tammo Winkler 《Chemoecology》2000,10(4):205-209
Summary. Two recently identified compounds ("CIFs"), present on the leaf surface of Brassica oleracea (cabbage), are the strongest oviposition stimulants known for the cabbage root fly, Delia radicum. Cabbage leaves contain these compounds in extremely low concentrations, and the amount of CIFs obtained from purifying leaf
extracts was so small that it limited further research. We were able to purify far more of these two compounds from the roots
of Brassica napus var. napobrassica (rutabaga). Apart from being a richer source of CIFs, rutabaga roots are considerably easier to collect and process than
leaves. In addition, we isolated and identified a new CIF compound from the roots that is also very active in stimulating
oviposition in the cabbage root fly.
Received 26 May 2000; accepted 26 July 2000 相似文献
629.
V.?BoudonEmail author J.-P.?Champion T.?Gabard G.?Pierre M.?Lo?te C.?Wenger 《Environmental Chemistry Letters》2003,1(1):86-91
Highly symmetrical molecules such as CH4, CF4 or SF6 are known to be atmospheric pollutants and greenhouse gases. High-resolution spectroscopy in the infrared is particularly
suitable for the monitoring of gas concentration and radiative transfers in the earth's atmosphere. This technique requires
extensive theoretical studies for the modeling of the spectra of such molecules (positions, intensities and shapes of absorption
lines). Here, we have developed powerful tools for the analysis and the simulation of absorption spectra of highly symmetrical
molecules. These tools have been implemented in the spherical top data system (STDS) and highly-spherical top data system
(HTDS) software available at http://www.u-bourgogne.fr/LPUB/shTDS.html. They include a compilation of modeled data obtained
during the last 20 years. An overview of our latest results in this domain will be presented.
Electronic Publication 相似文献
630.
模拟5km急性低氧2h、4h、8h和24h,观察大鼠海马白介素6(IL6)和低氧诱导因子1(HIF1α)表达的时序变化.分别运用免疫组化和RTPCR分析海马CA1、CA2和CA3区IL6、HIF1α和海马HIF1αmRNA的表达水平.与对照组相比,5km急性低氧8h和24h,海马CA1区IL6水平升高14.24%(P<0.01)和7.76%(P<0.05);低氧8h,海马CA2和CA3区IL6水平上升3.1%(P<0.05)和5.1%(P<0.05).5km低氧4h、8h和24h,海马CA1区HIF1α水平分别升高3.67%(P<0.05)、5.5%(P<0.05)和6.27%(P<0.01),同时发现HIF1αmRNA在海马的表达上调.上述结果表明,5km急性低氧促进海马IL6和HIF1α的表达增强,推测HIF1α可能作为调控因子参与低氧下海马IL6的诱导表达.图5表1参21 相似文献