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71.
Three fetuses with TAR (thrombocytopenia with absent radii) or TAR variant syndrome were found to be thrombocytopenic during the third trimester of the pregnancy. These findings indicate that fetal blood sampling, besides ultrasonography, skeletal radiographs, or even fetoscopy, may indeed contribute to the prenatal diagnosis of TAR syndrome, and thus may help in differentiating TAR syndrome from other syndromes with malformations of the upper limbs.  相似文献   
72.
The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and contact time. The removal of Pb(II) was reach to maximum value 85% or 83% at pH 5 or 40 mg/L of CNTs, respectively. Higher correlation coefficients from Langmuir isotherm model indicates the strong adsorptions of Pb(II) on the surface of CNTs (adsorption capacity Xm = 102.04 mg/g). From this study, the results indicates that the highest percentage removal of Pb (96.03%) can be achieved at pH 5, 40 mg/L of CNTs, contact time 80 min, and agitation speed 50 r/min.  相似文献   
73.
Abstract

One of two topics explored is the limitations of the daily average in summarizing pollutant hourly profiles. The daily average of hourly measurements of air pollutant constituents provides continuity with previous studies using monitoring technology that only provided the daily average. However, other summary statistics are needed that make better use of all available information in 24-hr profiles. The daily average reflects the total daily dose, obscuring hourly resolution of the dose rate. Air pollutant exposures with comparable total daily doses may have very different effects when occurring at high levels over a few hours as opposed to low levels over a longer time. Alternative data-based choices for summary statistics are provided using principal component analysis to capture the exposure dose rate, while preserving ease of interpretation. This is demonstrated using the earliest hourly particle concentration data available for El Paso from archived records of particulate matter (PM)10. In this way, a significant association between evening PM10 exposures and nonaccidental daily mortality is found in El Paso from 1992 to 1995, otherwise missed using the daily average. Secondly, the nature and, hence, effects of particles in the ambient aerosol during El Paso sandstorms is believed different from that of particles present during stillair conditions resulting from atmospheric temperature inversions. To investigate this, wind speed (ws) is used as a surrogate variable to label PM10 exposures as Low-ws (primarily fine particles), High-ws (primarily coarse particles), or Mid-ws (a mixture of fine and coarse particles). A High-ws evening is significantly associated with a 10% lower risk of mortality on the succeeding third day, as compared with comparable exposures at Low- or Mid-ws. Although this analysis cannot be used to form firm conclusions because it uses a very small data set, it demonstrates the limitations of the daily average and suggests differential toxicity for different particle compositions.  相似文献   
74.
Infantile polycystic kidney disease (IPKD) is an autosornal recesive inherited disorder, IPKD has been previously diagnosed by us as early as the 14th week of gestation. ‘Late onset’ (third trimester) IPKD has been previously described by several authors. We present here a case of intrauterine detection of ‘late onset’ IPKD, suggesting that elongated hyperechogenic kidneys (with normal transverse and anteroposterior diameters) should be considered as an early sign of ‘late onset’ presenting IPKD.  相似文献   
75.
Transabdominal chorionic villus sampling (TA-CVS) was performed in 707 viable singleton pregnancies to exclude chromosomal abnormalities. Maternal age ranged between 36 and 49 years (mean 37·9 years); gestational age varied between 10·2 and 18·3 weeks (mean 13·3 weeks). In 639 women (90·4 per cent), a sufficient amount of chorionic tissue (⩾ 10 mg) was obtained after one needle insertion; in 66 women (9·3 per cent) two insertions were needed. An abnormal chromosome pattern was established in 19 cases (2·9 per cent). Vaginal bleeding or spotting within 28 days after TA-CVS occurred in 11 cases (1·5 per cent). The completed follow-up of 678 chromosomally normal pregnancies showed an overall fetal loss rate of 2·6 per cent before 28 weeks. The overall perinatal mortality was 0·9 per cent. When relating fetal loss to gestational age at TA-CVS, this was 6·6 per cent in women sampled before 12 weeks against only 1·8 per cent after 12 weeks. At the same time, the percentage of fetal loss occurring within 2 weeks following the procedure was 75 and 30 per cent, respectively. It is suggested that these data reflect the decline in spontaneous abortion rate during this particular period of pregnancy. It is concluded that TA-CVS is an effective procedure which, when performed after the natural decrease of fetal loss, appears to be a safe option for women of advanced maternal age.  相似文献   
76.
A case of combined partial mole and neural tube defect is presented. The detection of high levels of both maternal serum (MS) alpha-fetoprotein (AFP) and human chorionic gonadotrophin (hCG) during the second trimester led to the ultrasonic demonstration of anencephaly, omphalocele, and partial mole. This is the first report of combined elevation of MSAFP and MShCG.  相似文献   
77.
We studied two children born to a myasthenic mother. The first child, a female, had multiple flexion contractures. She died 1 h after birth. In the second pregnancy, 3 years later, ultra-sonographic examination at 20 weeks showed decreased fetal movements and multiple flexion contractures. The pregnancy was interrupted. Eight other cases of congenital rnyasthenia with arthrogryposis are known; four of them are siblings. The recurrence risk may be as high as 100 per cent. Our second case demonstrates that prenatal diagnosis is possible early enough to allow termination of pregnancy.  相似文献   
78.
The aim of this study was to determine the efficacy of combined maternal serum alpha-fetoprotein (MSAFP) and maternal serum human chorionic gonadotropin (MShCG) screening in detecting chromosome defects in the first trimester of pregnancy. Sera of 492 women (previously assayed for MSAFP) were analysed for MShCG under code without knowledge of cytogenetic results. Overall, 48 of 492 patients (9·8 per cent) had either an MSAFP multiple of the median ⩽0·5 or an MShCG β/a z ratio multiple of the median ⩽ 0·25, eight of whom had a fetus with a serious chromosome defect. A third of fetuses with Down' s syndrome and 83 per cent with trisomy 18 were detected at a potential‘cost’ of providing chorionic villus sampling or amniocentesis in 8·6 percent of women screened.  相似文献   
79.
Nine patients with oligohydramnios and amnio-chorionic separation were identified out of 7000 women who underwent a vaginal ultrasound examination at 15–16 weeks' gestation. Oligohydramnios was defined as a reduced amount of amniotic fluid, a distance of more than 1 cm between the chorion and amnion, and a good turgor of the amnion without floating membranes or intrauterine sheets. Fetal malformations were observed in all nine cases. In four of six fetuses where chromosomal analysis was available, an abnormal karyotype was found. It is concluded that oligohydramnios in the early second trimester is associated with fetal abnormality.  相似文献   
80.
Two cases of sirenomelia are described, detected in the 14th and 16th weeks of gestation by transvaginal ultrasonography. A hypothesis for the aetiology of sirenomelia and its associated anomalies is discussed.  相似文献   
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