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The objective of this study is to determine whether a normal fetal morphology ultrasound scan in women older than 35 years reduces the risk of aneuploidy. We reviewed the results of amniocentesis and second trimester sonogram in all women older than 35 years from 1991 to 1995. None had prior screening. We excluded fetuses with structural anomalies. We determined the sensitivity and specificity of minor markers in detecting Down syndrome and also determined the reduction in risk of a normal sonogram. Among the 2060 women older than 35 years giving birth during the study period, 16 (0.78%) delivered an infant with Down syndrome. Of the 16 fetuses, two had no prenatal testing or ultrasound, two had invasive testing but no second trimester sonogram, five had a normal sonogram and seven had one or more sonographic markers of Down syndrome. At least 17% of women older than 35 years did not participate in prenatal testing or ultrasound. Ultrasound detected Down syndrome with a sensitivity of 59% (95% confidence interval: 45–72%), a false‐positive rate of 10.6% (9.4–11.8%) and a positive predictor value of 1 in 9. The likelihood of having normal karyotype if the sonogram was normal was 0.46 (0.31–0.61). In women older than 35 years, a normal second trimester sonogram reduces the risk of Down syndrome by more than 50%. At least 17% of women older than 35 years do not participate in prenatal testing or ultrasound. 相似文献
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烧伤后机体应激导致代谢紊乱,表现为严重高分解代谢,机体损耗和抵抗力下降,严重影响患者预后。临床上主要采用生理营养指标、实验室诊断指标和能量消耗测定3类检测指标对机体代谢状况进行诊断评估,继而通过药物治疗结合非药物治疗手段加以调理支持,促进烧伤修复。目前,仍有多种诊断治疗方法尚未普及或有待完善。 相似文献
85.
多层螺旋CT(MSCT)使扫描速度,薄层,覆盖范围达到了很好的统一,是胰腺癌最佳的单项检查手段。本文介绍了MSCT运用于胰腺的技术优势以及具体检查方法,重点叙述其在胰腺癌的诊断,术前可切除性的评估等方面的应用。 相似文献
86.
Objective To establish a means for prenatal prediction of spinal muscular atrophy (SMA) through survival motor neuron (SMN) gene deletion analysis and genetic counseling in families with a child affected with SMA.
Methods Genetic analysis for prenatal prediction of Werdnig-Hoffmann disease was performed in a at risk Chinese family by polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) in SMN gene exons 7 and 8.
Results The pregnancy was positive for the homozygous deletion of the SMN gene, thus the fetus was diagnosed as being affected and the pregnancy was terminated.
Conclusion This approach is fast and reliable for DNA-based prenatal diagnosis of Werdnig-Hoffmann disease. 相似文献
Methods Genetic analysis for prenatal prediction of Werdnig-Hoffmann disease was performed in a at risk Chinese family by polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) in SMN gene exons 7 and 8.
Results The pregnancy was positive for the homozygous deletion of the SMN gene, thus the fetus was diagnosed as being affected and the pregnancy was terminated.
Conclusion This approach is fast and reliable for DNA-based prenatal diagnosis of Werdnig-Hoffmann disease. 相似文献
87.
Hiroyuki ARAI 《Psychogeriatrics》2005,5(3):83-88
Alzheimer's disease (AD) generally begins with mild memory problems which occur in an insidious manner and progresses to the development of multiple cognitive impairments. There is a ‘gray’ area between what is classified as ‘normal’ and what is classified as ‘dementia’, currently called mild cognitive impairment (MCI). In this article, a case of MCI is described, and the diagnosis, assessment, subclassification (pre‐Alzheimer type and white matter lesion type) and future therapeutic plans for MCI are reviewed. 相似文献
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目的探讨Cockett综合征影像学诊断和介入治疗方法。方法对20例Cockett综合征患者进行临床分析,其中13例行介入治疗术。结果下肢深静脉造影术能明确诊断Cockett综合征,13例患者经介入治疗后其临床症状体征均有不同程度的改善,临床疗效明显。结论介入治疗Cockett综合征,是一种简单、安全和有效的方法。 相似文献
90.