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M. H. B. Carvalho M. L. Brizot L. M. Lopes C. H. Chiba S. Miyadahira M. Zugaib 《黑龙江环境通报》2002,22(1):1-4
The aim of this study was to evaluate the detection of fetal structural abnormalities by the 11–14 week scan. 2853 pregnant women were submitted to a routine ultrasound scan between the 11th and 14th week and the fetal skull, brain, spine, abdominal wall, limbs, stomach and bladder were examined. Following the scans the patientes were examined in the second or third trimester of pregnancy. An isolated increased nuchal translucency was not considered an abnormality. However, these patients had an early echocardiography assessment. Fetal structural abnormalities were classified as major or minor and of early or late onset. A total of 130 (4.6%) defects were identified and 29 (22.3%) of these were diagnosed at the 11–14 week scan, including nine cardiac defects associated with increased nuchal translucency. The antenatal ultrasound detection rate was 71.5%, and 31.2% were detected in the first-trimester assessment. 78.8% of the major defects were diagnosed by the prenatal scan and 37.8% by the 11–14 week scan. Fetal structural abnormalities at the 11–14 week scan were detected in approximately 22.3% of the cases, therefore, a second-trimester anomaly scan is important in routine antenatal care to increase the prenatal detection of fetal defects. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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This article presents the methods and results of visual interpretation of NOAA AVHRR imagery for mapping flood areas in Bangladesh.
Color composites of channels 1 and 2 for 18 August 1987 and 10, 15, and 24 September 1988 were interpreted visually for delineating
flood boundaries. On such imagery flood areas appear in dark tones and are separated from land (light tones) owing to the
absorption of near infrared by water and its reflectance by land and non-waterbodies. Visual interpretation was aided by the
use of ground information, such as physiographic and river maps, previous flood maps, newspaper reports, and other published
and unpublished documents on the 1987 and 1988 floods. Interpreted flood areas on selected images ranged from 31% to 43% of
the total area of Bangladesh. Visual interpretation overestimated flood areas by 5%–10%, compared to the digitally analyzed
data. The main advantage of visual analysis lies in the cost effectiveness of AVHRR photographic products, which make them
more accessible than the digital image analysis of computer-compatible tapes. 相似文献
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Chih-Ping Chen Schu-Rern Chern Chin-Yuan Tzen Meng-Shan Lee Chen-Wen Pan Tung-Yao Chang Wayseen Wang 《黑龙江环境通报》2001,21(4):317-320
In utero diagnosis of de novo distal 11q deletion associated with renal and orofacial malformations has not been previously described. We present a 35-year-old pregnant woman with prenatal sonographic findings of a unilateral duplex renal system, pyelectasis and orofacial clefts at 20 weeks' gestation. Both genetic amniocentesis and postnatal cytogenetic analysis revealed de novo 46,XX,del(11)(q23). After birth, the fetus manifested a dysmorphic phenotype correlated with del(11q) syndrome. Genetic marker analysis showed a paternally derived distal deletion of chromosome 11q and a breakpoint centromeric to D11S1341. The present case represents the earliest prenatal diagnosis of a duplex renal system, pyelectasis and an additional feature of orofacial clefts associated with distal 11q deletion. Prenatal sonographic detection of a duplex renal system, pyelectasis and orofacial clefts should warrant a careful assessment of fetal anatomy and prompt cytogenetic analysis looking for chromosomal aberrations. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献