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381.

Objective

To determine screening performance of maternal, fetal and placental characteristics for selecting pregnancies at risk of gestational hypertension and preeclampsia in a low-risk multi-ethnic population.

Method

In a prospective population-based cohort among 7124 pregnant women, we collected maternal characteristics including body mass index, ethnicity, parity, smoking and blood pressure in early-pregnancy. Fetal characteristics included second and third trimester estimated fetal weight and sex determined by ultrasound. Placental characteristics included first and second trimester placental growth factor concentrations and second and third trimester uterine artery resistance indices.

Results

Maternal characteristics provided the best screening result for gestational hypertension (area-under-the-curve [AUC] 0.79 [95% Confidence interval {CI} 0.76-0.81]) with 40% sensitivity at 90% specificity. For preeclampsia, the maternal characteristics model led to a screening performance of AUC 0.74 (95% CI 0.70-0.78) with 33% sensitivity at 90% specificity. Addition of second and third trimester placental ultrasound characteristics only improved screening performance for preeclampsia (AUC 0.78 [95% CI 0.75-0.82], with 48% sensitivity at 90% specificity).

Conclusion

Routinely measured maternal characteristics, known at the start of pregnancy, can be used in screening for pregnancies at risk of gestational hypertension or preeclampsia within a low-risk multi-ethnic population. Addition of combined second and third trimester placental ultrasound characteristics only improved screening for preeclampsia.
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The present study on environmental pollution in northern Vietnam investigates elemental concentrations in fine particulate matter (PM2.5), freshwater, and aquatic biota at two sites with differing levels of industrial activities. An Thin is situated 47 km east of Hanoi in the neighbourhood of a coal combustion power plant, whereas the reference site, Duy Minh, is situated in the agricultural province of Ha Nam, 40 km south of Hanoi. Elemental concentrations were analysed using energy-dispersive X-ray fluorescence, total reflection X-ray fluorescence, and graphite furnace atomic absorption spectro-metry. All investigated elements in fine particles (PM2.5) had significantly higher concentrations in An Thin, thus identifying the air at this site as polluted. In contrast to the aerosol samples, elemental concentrations as well as quantitative differences between the sampling sites were low in freshwater and biota, indicating that the impact of atmospheric deposition was limited.  相似文献   
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Objective Fluorescence in situ hybridization (FISH) analysis has become a valuable adjunct in cytogenetics, providing a rapid screen for common chromosome abnormalities that is particularly helpful in prenatal diagnosis. FISH analysis using standard microscopy is expensive and labor intensive, requiring both a high skill level and subjective signal interpretation. A reliable fully automated system for FISH analysis could improve laboratory efficiency and potentially reduce errors and costs. Methods The efficacy of an automated system was compared to standard manual FISH analysis. Two sets of slides were generated from each of 152 amniotic fluid samples. Following hybridization with a standard panel of five chromosome FISH probes, one set of slides was evaluated using manual microscopy. The other set was evaluated using an automated microscopy system. Results A diagnostic outcome was obtained for all 152 samples using manual microscopy and for 146 of 152 (96%) samples using automated microscopy. Three cases of aneuploidy were detected. For those samples for which a diagnostic outcome was determined by both manual and automated microscopy, 100% concordance was observed. All FISH analysis results were confirmed by karyotype. Conclusion These data suggest that an automated microscopy system is capable of providing accurate and rapid enumeration of FISH signals in amniocytes. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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