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91.
Five pregnancies at risk for X-linked retinitis pigmentosa (RP) have been monitored by first-trimester prenatal diagnosis using DNA markers flanking the RP2 and RP3 loci. Three affected and two unaffected fetuses, including a female carrying a wild-type genotype, were predicted on the basis of marker segregation and estimation of the recombination fraction.  相似文献   
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Prenatal diagnosis performed by ultrasound scan is now a routine part of antenatal care in our region. How many fetal anomalies are actually detected by this procedure? We have used our registry of congenital malformations to answer this question regarding limb reduction defects (LRDs). The mean time of detection of LRDs was 26 weeks of pregnancy (range 16–32 weeks). The sensitivity of prenatal diagnosis of LRDs by ultrasonographic examination was much lower for isolated malformations (fetuses with only one anomaly) than for multiply malformed children with LRDs, 4·0 and 18·2 per cent, respectively. For all cases of LRDs, the percentage of prenatal detection was 11·5. Termination of pregnancy was performed in 6·7 per cent of the cases.  相似文献   
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Policy indicators applied at a national scale can have considerable financial impact for resource allocations to individual counties, especially if there are extreme local factors. This article develops arid explores a new measure of population dispersal and sparsity and discusses the impact of this indicator in a variety of locations, by using GIS techniques.  相似文献   
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Conclusions Despite these problems there are a number of positive cases, where exemplary solutions have been found after long processes of negotiation and compensation and which can stand as examples of what can be achieved in a re-organisation of the environment and housing structure between the Ruhr and the Lippe.The transformation of the old Rosenblumendelle pit in Mülheim into a shopping centre, the create of a modern industrial park on the land of the old Friedrich Ernestine pit in Essen (from the pit closure to the establishment of the park the whole process only took four and a half years!), and the transformation of the old Dahlhauser Tiefbau pit in Bochum into a leisure and recreation area, which will soon be completed. These and other examples show that reclamation, given favourable circumstances, can be very successful indeed.  相似文献   
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First trimester prenatal diagnosis was offered to the mother of a child affected by severe haemolytic anaemia due to glucose phosphate isomerase (GPI) deficiency. The mutant enzyme was characterized by an increased thermal lability. Both parents had 50 per cent normal red cell GPI activity. We have shown that the homozygous and heterozygous genotypes can be clearly distinguished from each other and controls by combinations of the measurement of enzyme activity and enzyme thermal lability. Examination of trophoblast cells obtained at 9 weeks of gestation led to the diagnosis of a GPI heterozygous fetus. The result was confirmed by analysis on uncultured and cultured amniotic fluid cells sampled at 16 weeks and by red blood cell studies of the healthy newborn. Prenatal diagnosis of GPI deficiency is indicated in families with previous cases resulting in severe haemolysis and mainly with the conservative view of arranging appropriate therapeutic measures for affected fetuses.  相似文献   
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