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511.
A. C. C. van Oppen E. J. Breslau-Siderius Ph. Stoutenbeek A. J. Pull Ter Gunne J. M. W. M. Merkus 《黑龙江环境通报》1991,11(12):915-920
Tuberous sclerosis is a single gene autosomal-dominant disorder, characterized by multiple hamartoma formation. It shows a wide variability of expression. Prenatal diagnosis by means of a DNA or biochemical marker is not yet possible. Ultrasound offers the only way to detect possible antenatal hamartoma formation, which is most commonly found in the central nervous system, the renal system, and the heart. We report a case of fetal involvement that appears unique because of the unusual location of a tumour in the neck of the fetus. 相似文献
512.
R. J. A. Penketh J. D. A. Delhanty J. A. van den Berghe E. M. Finklestone A. H. Handyside S. Malcolm R. M. L. Winston 《黑龙江环境通报》1989,9(7):489-499
Sixty spare human embryos at various stages of preimplantation development were prepared for cytogenetic analysis. Fluorescent staining of those with metaphases allowed scoring for the presence of a Y chromosome. In situ hybridization was then performed using a biotinylated Y-specific sequence, and the probe was detected by a standard streptavidinlinked alkaline phosphatase system. This enabled comparison of the chromosomal sex with that obtained after in situ hybridization in 28 embryos, and the sexing result obtained by the two methods was concordant in all cases. A further 21 embryos in which no metaphase chromosomes were obtained were sexed by biotinylated in situ hybridization only. Overall, 66 per cent of male interphase nuclei demonstrated a Y-specific hybridization signal. Results were obtained in under 24 h, which may permit the sexing of an embryo biopsied during cleavage and the transfer of sexed embryos at the blastocyst stage to the mother's uterus in the same cycle as oocytes are collected for in vitro fertilization. 相似文献
513.
W. Lissens M. Van Lierde J. Decaluwe W. Foulon P. Evrard F. van Hoof M. Freund I. Liebaers 《黑龙江环境通报》1988,8(1):59-62
The X-linked Hunter syndrome or mucopolysaccharidosis II was diagnosed in a male fetus by demonstrating a severe deficiency of iduronate 2-sulphate sulphatase activity in fetal plasma obtained by umbilical fetal blood sampling at 23 weeks of pregnancy. The diagnosis was confirmed after termination of pregnancy. 相似文献
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Jan Willem Erisman Arjan Hensen Wim de Vries Hans Kros Tamme van de Wal Wim de Winter Jan Erik Wien Mark v. Elswijk Matthijs Maat Kaj Sanders 《Ambio-人类环境杂志》2002,31(2):190-196
利用计算机模拟的方法,我们为第二届国际氮会议研制开发了一个游戏形式的氮决策支持系统.研制这一系统的目的是:①使科学工作者和决策者们都能认识到荷兰氮污染问题的复杂性,因为荷兰是一个农业、工业和运输业活动密集的区域;②探索以最低的社会经济代价解决氮污染的最佳方案.NitroGenius由有关时空范围内的氮流动模型组成,其中包括氨和氮氧化合物的释放及其对地表水和地下水的污染.NitroGenius中还包括了一个经济模型,它描述了各个重要经济部门之间的关系,以及不同氮排放控制措施对国民生产总值(GDP)、失业率、能源消耗和环境的影响.在第二次国际氮会议期间,大约有50个研究组对NitroGenius进行了测试,结果表明,如果认真进行计划并选择适当的治理措施,就能够以适当的代价解决荷兰的氮污染问题. 相似文献
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Leukocyte adhesion deficiency (LAD) is a rare autosomal recessive disorder which leads to recurrent severe infections due to impaired leukocyte functions. The disorder is caused by an absence or deficiency of leukocyte cell adhesion molecules (LeuCAMs) on the leukocyte membranes. The diagnosis is established with monoclonal antibodies against the LeuCAMs. We have carried out a prenatal diagnostic procedure by means of cordocentesis in a mother who was 20 weeks pregnant and had previously given birth to a child with LAD. This previous child had the severe form of LAD with undetectable mRNA for the β chain, the common subunit of the LeuCAMs. We found that the fetal granulocytes expressed the LeuCAMs normally. At birth, the baby was physically normal and showed no signs of impaired leukocyte functions. 相似文献
519.
6 ha, or 6% of the country's total area. The environmental implications of this large-scale conversion have so far received
little attention; the present study examined some of these implications. A review of research on soil physical and chemical
aspects of the conversion of permanent grassland into arable land reveals that such a large-scale conversion may have considerable
effects upon the environment. For example, due to the mineralization of soil organic matter a release of NO3 and CO2 into the environment can be expected on the order of 10 t N and 100 t C per hectare. Environmentally equally severe, if not
worse, is the increased amount of surface runoff that can be expected from converted grassland soils in arable land during
winter because of surface sealing and soil compaction. This increased surface runoff, in combination with the runoff from
other farmland, may be one of the reasons for the growing frequency of floods along major German rivers in recent years. In
view of the lasting adverse environmental effects of permanent grassland conversion and the subsidized agricultural surpluses
in Germany today, we conclude that a reconversion of arable land into permanent grassland may be beneficial both environmentally
and economically. 相似文献
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