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公路设计中的环境保护工作 总被引:1,自引:0,他引:1
阐述了公路建设中环境保护工作的意义,提出在公路工程勘察设计工作中对环境保护的典型作法和取得的效果。 相似文献
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H. Brandenburg MD W. De Koning M. G. J. Jahoda Th. Stijnen M. A. J. De Ridder E. S. Sachs J. W. Wladimiroff 《黑龙江环境通报》1992,12(12):1031-1035
One hundred and fifty-one women of advanced maternal age who underwent genetic termination of pregnancy (TOP) were studied for their reproductive behaviour and the type of procedure for prenatal diagnosis in a subsequent pregnancy. A total of 59 women (39 per cent) had a further pregnancy. In all continuing pregnancies prenatal diagnosis was performed, of which 75 per cent consisted of chorionic villus sampling (CVS). Reproductive behaviour following a genetic termination was negatively correlated with maternal age and parity. Both reproductive behaviour and the choice to undergo a diagnostic procedure in the next pregnancy were independent of the type of diagnostic procedure in the previous affected pregnancy. 相似文献
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B. Sikkema-Raddatz R. H. Sijmons M. B. Tan-Sindhunata A. Y. Van Der Veen R. Brunsting B. De Vries J. R. Beekhuis D. J. Bekedam B. Van Aken B. De Jong 《黑龙江环境通报》1995,15(5):467-473
We report two cases of apparently balanced complex de novo chromosomal rearrangements (BCCR) detected prenatally at 17 weeks and 10 weeks of gestation, respectively. Chromosomes were studied using GTG-banding and fluorescent in situ hybridization (FISH). In one case four chromosomes and in the other case three chromosomes were involved in the rearrangements. One of the pregnancies was terminated and no external or internal abnormalities were detected at autopsy. The other pregnancy continued to term. Level III ultrasound examination showed no abnormalities. The child is now 3 years old and has neither congenital anomalies nor evidence of delayed psychomotor development. 相似文献
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A Framework for Monitoring and Evaluating Carbon Mitigation by Farm Forestry Projects: Example of a Demonstration Project in Chiapas,Mexico 总被引:1,自引:0,他引:1
De Jong Ben H.J. Tipper Richard Taylor John 《Mitigation and Adaptation Strategies for Global Change》1997,2(2-3):231-246
Mitigation and Adaptation Strategies for Global Change - In Mexico an estimated 4.5 × 106ha are available for farm forestry, while up to 6.1 × 106 ha could be saved from deforestation by... 相似文献
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M. Van Blerk MD J. Smitz L. De Catte C. Kumps J. Van Der Elst A. C. Van Steirteghem 《黑龙江环境通报》1992,12(12):1062-1066
This study explores if assay of cancer antigen 125 (CA 125) in maternal serum might aid the detection of Down's syndrome in the second trimester of pregnancy. CA 125 levels were determined retrospectively in stored maternal serum samples from ten Down's syndrome pregnancies and 78 controls matched for gestational and maternal age. In addition, second-trimester amniotic fluid samples from nine Down's syndrome and 109 unaffected pregnancies were analysed for CA 125. Maternal serum CA 125 values for Down's syndrome pregnancies were lower, with the median being 0.72 multiples of the unaffected population median. The medians for affected and unaffected pregnancies did not differ significantly and there was a considerable overlap in the range of values of cases and controls. The distribution of amniotic fluid CA 125 levels for Down's syndrome pregnancies resembled that for controls. From our present results, we could not find an association between Down's syndrome and second-trimester maternal serum or amniotic fluid CA 125 levels. 相似文献
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