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171.
Cytomegalovirus (CMV) is the most common cause of intrauterine infection. Recent publications show amniocentesis to have an 81–100 per cent sensitivity in antenatal diagnosis after 21 weeks' gestation. Testing before 21 weeks' gestation is less well documented. We performed 36 amniocenteses between 14 and 20 weeks' gestation. The sensitivity was 45 per cent and the specificity 100 per cent. Implications and possible causes of this low sensitivity are discussed.  相似文献   
172.
Chorionic villus sampling (CVS) with either transcervical catheters or transabdominal needles is a widely-accepted method for prenatal diagnosis. However, there exists a small subset of patients in whom sampling is difficult or impossible with either route because of individual anatomic variations. A new method of chorionic villus biopsy has been developed to circumvent these problems, utilizing transvaginal chorionic needle aspiration guided by an intravaginal ultrasound probe. This technique was performed successfully in 15 patients in whom villi could not be obtained by either of the conventional methods. This method now makes CVS possible in essentially all women regardless of their uterine anatomy or placental placement; it may also prove useful for very early chorionic sampling.  相似文献   
173.
This paper reports results of an exploratory study of prenatal diagnosis patients who experienced voluntary terminations of pregnancy following the detection of an abnormality or spontaneous miscarriages. The 121 participants were part of the national collaborative Chorionic Villus Sampling and Amniocentesis Study. They completed semi-structured telephone interviews and mailed questionnaires at 1 month and 6 months after the pregnancy losses. Scores on the Profile of Mood States showed that mood levels improved significantly over time. However, there were some declines in loss-related support from partners and others. The persisting distress and difficulties of a minority highlight the variability in women's responses to pregnancy losses. Women who lost pregnancies later in gestation, showed the greatest mood disturbances at initial assessments, used professional mental health assistance after the loss, or reported less satisfactory loss-related support from significant others showed the greatest levels of mood disturbance at the six-month assessment. Follow-up contacts with patients who lose pregnancies should be used to inform women about the variation in possible grief reactions, to assess the extent of support the women are receiving from their partners and significant others, and to provide additional follow-up or referral of those experiencing the greatest distress.  相似文献   
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Prenatal real-time ultrasonographic diagnosis of microphthalmia is presented. Diagnosis was made at 18 weeks' gestation in a fetus of a patient with a previous infant affected with the syndrome of cryptophthalmia with absence of septum nasi and ambiguous genitalia (Fraser syndrome). Recognition of microphthalmia as a part of Fraser syndrome and the easy visualization of fetal facial bones and orbits in the second trimester made the diagnosis possible.  相似文献   
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We have investigated the ability of high-resolution proton NMR spectroscopy to provide a biochemical constituent screening of human amniotic fluid (AF). Proton NMR spectra were obtained at 300 MHz on AF from patients undergoing amniocentesis in the mid-trimester. Only AF from normal pregnancies (normal fetal karyotype, normal a-fetoprotein levels, normal birth outcome) was used in this study. The AF supernatant was lyophilized and resuspended in deuterated water containing 0.1 mm phosphate buffer and 6.02 mm disodium maleate. Identification of low molecular weight compounds was confirmed by two-dimensional NMR spectra (primarily correlated spectroscopy, or COSY) and standard addition techniques. A broad profile of compounds were ‘NMR visible’ in a single proton spectrum, including creatinine, glucose, organic acids (acetate, citrate, and lactate) and several amino acids (alanine, histidine, leucine, phenylalanine, tyrosine and valine). The proton spectrum was unaffected by prior freezing/thawing of AF samples. We were able to quantify compounds by comparison with an added concentration standard (maleate) at concentrations as low as 30 μm. Good agreement with literature values based on other analytical techniques was obtained.  相似文献   
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