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Pirkko Ämmälä Vilho K. Hiilesmaa Sirkka Liukkonen Terhi Saisto Kari Teramo Harriet Von Koskull 《黑龙江环境通报》1993,13(10):919-927
A total of 800 patients were randomized at the 9th to 11th week of pregnancy either for transcervical chorionic villus sampling (CVS) on the day of trial entry or for amniocentesis (AC) at the 16th week. The indication for fetal karyotyping was maternal age in 94 per cent of the cases; the mean maternal age was 39.2 years. An adequate sample was obtained in 98.3 per cent of the cases in the CVS group and in all cases in the AC group. Retesting was indicated in 3.3 per cent of the CVS cases. An abnormal karyotype was found in 6.1 per cent of the CV samples and in 4.5 per cent of the amniotic fluid samples. There was one false-positive chromosome result in both groups. Twelve (3.1 per cent) miscarriages occurred by the 22nd week of pregnancy in the CVS group in pregnancies intended to continue. No difference was seen between the groups for total fetal loss rates. The number of surviving infants in the CVS group was 92.2 per cent and in the AC group 91.7 per cent (rate difference 0.5 per cent (95 per cent confidence interval − 3.3 to 4.3)). In our study, both the diagnostic accuracy and the risk of fetal loss were equal in the CVS and AC groups. 相似文献
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Livia Poenaru Christine Mezard Said Akli Jean-François Oury Yves Dumez Joëlle Boue 《黑龙江环境通报》1990,10(4):231-235
We investigated the possibility of prenatal diagnosis of mucolipidosis type II (ML II) by lysosomal enzyme determination on amniotic fluid obtained at 11 weeks of gestation in three pregnancies at risk. Diagnosis of ML II was made in one case on the basis of increased levels of five lysosomal enzymes tested. The diagnosis was confirmed on cultured chorionic cells, their cultured medium, 17–week amniotic fluid, and fetal plasma obtained for confirmation prior to the termination of pregnancy. 相似文献
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Haapala H Goltsova N Seppälä R Huttunen S Kouki J Lamppu J Popovichev B 《Environmental pollution (Barking, Essex : 1987)》1996,91(2):253-265
The effects of air pollutants on forests around the eastern part of the Gulf of Finland were studied by measurement of the sulphur and calcium content of pine needles and evaluation of the ecological conditions of pine forests. Several parameters for pine trees and their needles were chosen as well as the species composition and condition of epiphytic lichens. Very high pine needle S- and Ca-contents were measured in the vicinity of the Narva and Slantsy plants. In this region both the acid and basic pollutant load is massive, partly neutralizing each other. It is suggested that the total load will, sooner or later, cause unexpected environmental damage. Wide 'lichen desert' areas were detected around Narva and Slantsy. Near the margins of these areas extraordinary epiphytes on pines were observed namely Xanthoria parietina (L.) Th.Fr. and red-coloured green alga Trentepohlia umbrina. They are regarded as indicators of alkaline pollution. The lowest pine needle S- and Ca-contents of the study area were measured in south-eastern Finland. The condition of pine forests and their needles was, however, better on the neighbouring Karelian Isthmus although the species number of epiphytic lichens was very low and the condition of the lichens was poor. It is suggested that these most sensitive indicators of air pollutants are damaged by pollutants from St Petersburg and Narva. Vast virgin forests of the Karelian Isthmus act as pollutant sinks reducing the effect of pollutants on trees. On the Finnish side intensive forest management has been carried on for many decades making forests and trees more sensitive to pollutants. 相似文献
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人们是否能够对波罗的海各亚区营养状况的变化作出可靠的结论还存在着疑问,其主要原因是显示出较高自然变化性的生产力参数是以稀疏采样为基础的,这就突显了长期数据集的重要性.我们在此提供了一个30年期的芬兰湾西部叶绿素α的数据集.该研究区域的营养状况显示,20世纪七八十年代营养盐含量存在着上升的趋势,主要表现为春季水华加强的趋势.这一趋势在20世纪90年代没有继续出现,并且自此浮游植物的季节性最大值也开始表现出一些向夏末的偏移.浮游植物水华的季节性最大值的变化可能会反映出如下几个方面的信息①氮的可获得性降低抑制了春季水华,这提高了夏季时磷的储备量;②磷的内部沉积量增加,从而能够进一步提高夏季时磷的储备量. 相似文献