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41.
Fluoride (Fl) exerts an inhibitory effect on many metabolic enzymes of various tissues. A study was carried out among individuals residing in a Fl-affected area in India. The biochemical parameters including serum enzyme activities of alkaline phosphatase (ALKP), glutamic pyruvic transaminase (SGPT), lactate dehydrogenase (LDH), and serum creatinine (CRTN) were estimated in 259 subjects compared to 233 controls. The results showed that among the Fl-exposed population, ALKP and SGPT were significantly increased compared to control. The CRTN levels were also significantly increased compared to the control subjects. LDH levels were not markedly altered. Data suggest that Fl exposure affects renal and hepatic functions in endemic areas of India.  相似文献   
42.
The impact of bisphenol A (BPA) on Gammarus fossarum and Lumbriculus variegatus was studied in four artificial indoor streams (0, 5, 50 and 500?µg?L?1 BPA, nominal) over 103 days in a pulse–dose exposure scenario (weekly BPA application). For G. fossarum populations at day 103, the proportions of juveniles and of breeding females from the highest BPA treatment were in tendency reduced. For individually exposed gammarid pairs an EC10 of 17?µg?L?1 BPA (nominal) for the proportion of reproductive females in the fourth brood was determined. During the first three broods, the largest brood size occurred at the highest BPA concentration, whereas in the fourth brood it decreased concentration-dependently (fourth brood EC10?=?5?µg?L?1 BPA, nominal). Effects on L. variegatus were a reduced population growth (103?d-EC10 of 2?µg?L?1 BPA, nominal) and an increase in dry weight and the number of segments in large, complete worms.  相似文献   
43.
Maternal serum unconjugated oestriol (uE3) was measured in 15 375 pregnancies during 2 years of second-trimester risk assessment for Down syndrome using biochemical markers. Very low levels of uE3 (<0·1 MOM) were detected in 22 serum samples (0·14 per cent). Very low uE3 was associated with an adverse outcome in 13 pregnancies including fetal death and miscarriage (N=11), anencephaly (N=1), and Meckel—Gruber syndrome (N=1). Dry scales on the skin appeared in the first year of life in four boys. From dermatological diagnosis, prenatal uE3 levels, and pedigree analysis, it is concluded that at least 5 in approximately 7500 male births in the study population are affected by steroid sulphatase deficiency, which is the biochemical defect in X-linked ichthyosis. Very low uE3 levels in the second trimester are indicative of this disease in pregnancies with normal ultrasound findings.  相似文献   
44.
Foci of calcification were observed at autopsy in the liver of a fetus with complete trisomy 9 on which two cordocenteses had been performed. It is suggested that liver calcifications are a possible complication of the procedure. As several other cases of calcifications in the liver and other organs of fetuses with autosomal trisomies have been described without a history of cordocentesis, further studies should be carried out to determine whether fetuses with chromosomal anomalies are more prone to thrombus formation and embolization.  相似文献   
45.
Trisomy 10 was detected at amniocentesis undertaken following observation of fetal nuchal oedema. This is the first report of fetal trisomy 10 in association with nuchal oedema. The physical features of fetal trisomy 10 are described.  相似文献   
46.
We report our cytogenetic experience of 1554 early amniocenteses between weeks 11 and 14 of gestation, of which 44 per cent were performed prior to week 14. The mean culture time was 14·5 days. Karyotyping was successful in 99·7 per cent of cases. In 9·9 per cent of cases, there was pseudomosaicism with a high rate of loss of an X-chromosome and structural aberration of chromosome 1, which may be due to the Chang medium. The mosaic rate was 0·5 per cent. The overall aberration rate was 2·8 per cent. Our data confirm the reliability of early amniocentesis, which is a serious alternative to standard amniocentesis and chorionic villus sampling (CVS).  相似文献   
47.
Amniocentesis at 17 weeks' gestation revealed a mosaic karyotype—46,XX/46,XX, — 14,+dic(14)(p11). No abnormalities were detected on ultrasound. Growth and placentation were normal. The fetus was examined after termination of pregnancy and micrognathia and pulmonary hyperlobation were the only abnormalities detected. Several tissues were set up for cytogenetics, including fetal skin, kidney, ovary, and placenta. The diagnosis was confirmed by these studies. The level of mosaicism varied between tissues, with the trisomy 14 cell line highest in amniotic fluid.  相似文献   
48.
49.
Maternal serum alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (βhCG) measurements taken prior to chorionic villus sampling (CVS) in 21 patients who subsequently miscarried were compared with measurements in a control group of 113 patients with uneventful pregnancies. Patients with AFP levels of 10 iu/ml or more prior to the CVS had a 4·3 times greater risk of miscarriage (95 per cent confidence interval 1·3–13·6). AFP levels obtained 1 week after the CVS in the 13 patients with late miscarriages were higher than in the control group (P = 0·06). Patients miscarrying had a greater rise in AFP (P = 0·06) and a greater fall in βhCG levels (P = 0·04) following the CVS procedure, compared with the control subjects. Each 10-unit change in the difference between AFP or βhCG levels prior to and 1 week following the CVS was associated with a significantly increased risk for late miscarriage. Elevated maternal serum AFP levels early in pregnancy and changes in AFP and βhCG levels following CVS may predict an increased risk for subsequent miscarriage.  相似文献   
50.
The histochemical measurement of urea-resistant alkaline phosphatase from maternal blood neutrophils is known to have a high detection rate for the prenatal detection of Down's syndrome pregnancies. However, because the histochemical method is laborious and subjective to use, it has not gained widespread acceptance in prenatal screening programmes. We present a simple and objective method for the measurement of urea-resistant alkaline phosphatase by flow cytometry. The method should allow the design of larger studies aimed at evaluating the role of neutrophil urea-resistant alkaline phosphatase in the prenatal screening for Down's syndrome.  相似文献   
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