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31.
The attitudes of 190 patients who had undergone chorionic villus sampling (CVS) were assessed by means of a questionnaire. One hundred and fifty-two patients replied of whom 68 (45 per cent) were referred because of increased maternal age and in the other 84 cases the indications included previous chromosomal abnormalities, fetal sexing, DNA analysis, and biochemical analysis. One hundred and twenty-two patients had a transcervical procedure, 24 had a transabdominal, and six patients required both procedures. One hundred and forty-one patients (93 per cent) reported CVS to be a satisfactory procedure, and the same percentage thought earlier diagnosis was beneficial. Thirty-nine patients (81 per cent) reported a better experience with CVS than with a previous amniocentesis. A majority of patients (93 per cent) wished a CVS in a future pregnancy and 137 patients (97 per cent) would accept a risk of miscarriage from the procedure of twice that quoted for amniocentesis (1 per cent).  相似文献   
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A United Nations Framework Convention on Climate Change (UNFCCC) Joint Implementation (JI) host country has to make sure that JI projects are additional to avoid extra costs to generate the reductions necessary to cover the deduction of Emission Reduction Units (ERUs) from the country’s Kyoto Protocol emissions budget. A tender of ERUs by the government allows to generate additional reductions beyond the ERUs issued if it thoroughly checks project additionality. The government of New Zealand is running a tender for JI projects under the title “Projects to Reduce Emissions” since 2003. In two rounds, 10 million ERUs have been awarded and several projects have already entered into contracts with European buyers. The ratio of ERUs awarded to reductions achieved was 0.8 in the second tender. However it remains to be seen whether the additionality test of this tender is sufficient to exclude clearly non-additional projects.  相似文献   
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Hurler's disease was excluded in a fetus at 23 weeks' gestation by demonstrating normal iduronidase activity in fetal leucocytes following failure of amniotic cell culture after amnic-centesis at 16 and 19 weeks' gestation. The diagnosis was confirmed in the neonate.  相似文献   
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Transabdominal chorionic villus sampling (TA-CVS) was performed in 210 pregnancies from 13 to 38 weeks using a double-needle technique. The sampling success was comparable to first-trimester TA-CVS and the diagnostic success rate was 98.2 per cent for the short-term technique and 99.3 per cent for cultured villi. Two fetuses could not be karyotyped. We found the chromosome quality to be similar to that in the first trimester, comparing the number of G-bands and other chromosome attributes. There were no unintended losses in a group (n = 142) with no sonographic abnormality, except for one death in utero at 38 weeks, 20 weeks after sampling. Chromosomal aberrations were seen in 19 per cent of cases with abnormal sonograms (n = 58). One case of a discordant karyotype was found (false-negative prediction of Down's syndrome by the short-term preparation). There were no cases of fetal demise due to feto-maternal bleeding. It is suggested that double-needle TA-CVS in advanced pregnancies combines the advantages of rapid karyotyping of chromosomes of good quality and low risk for the fetus, and seems to be easier to practise and is probably safer than cordocentesis.  相似文献   
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Many authors have suggested that individuals affected by a terminal 1q deletion display a phenotypically definable and recognizable syndrome. In all of the 27 cases reported to date, the breakpoints were at band q42 or distally to it. To our knowledge, we report the first case of a terminal 1q41 deletion. Diagnosis was made prenatally by amniocentesis, following ultrasonographic diagnosis of omphalocele, cerebral ventriculomegaly, and increased nuchal fold thickness in a 19-week female fetus. Multiple facial and extremity features were consistent with the proposed distal 1q deletion syndrome; omphalocele, however, has not been reported previously. The absence of liver herniation into the omphalocele sac in this case supports the previously reported association of this finding with chromosomal anomalies.  相似文献   
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Selective feticide is the procedure of choice when, in twin binovular pregnancy, only one of the fetuses is shown to be affected. As the probabilities for this condition are almost 1:2 when the genetic disease is due to homozygosity for two autosomal recessive genes, the problem is expected to occur frequently among the ever increasing number of couples seeking prenatal diagnosis of thalassaemia and the haemoglobinopathies. The present report is the first case of this condition and the ninth in the overall medical literature.  相似文献   
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