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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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Mucolipidosis IV (ML 1V) is a lysosomal storage disease presenting in infancy with cloudy cornea and psychomotor retardation. Our experience with 12 pregnancies at risk for ML IV, monitored by transmission electron microscopy (TEM) studies of cultured amniotic fluid cells, is presented. The prenatal diagnoses were confirmed in the 3 affected and the 8 un- affected pregnancies. In the one pregnancy where no definite diagnosis was reached the pregnancy was terminated. TEM examination of fetal tissues from this pregnancy showed no abnormal lysosomal storage bodies and a review of the cultured amniotic fluid cell sections revealed that the diagnosis of a normal fetus could have been made.  相似文献   
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The objective of this study was to detect fetal HLA-DQα gene sequences in maternal blood. HLA-DQα genotypes of 70 pregnant women and their partners were determined for type A1. We specifically sought couples where the father, but not the mother, had genotype A1. In 12 women, maternal blood samples were flow-sorted. Candidate fetal cells were isolated and amplified by using PCR primers specific for a paternal HLA-DQα A1 allele. Fetal HLA-DQα A1 genotype was predicted from sorted cells; amniocytes or cheek swabs were used for confirmation. Six of twelve sorted samples had amplification products indicating the presence of the HLA-DQα A1 allele; 6/12 did not. Prediction of the fetal genotype was 100 per cent correct, as determined by subsequent amplification of amniocytes or cheek swabs. We conclude that paternally inherited uniquely fetal HLA-DQα gene sequences can be identified in maternal blood. This system permits the identification of fetal cells independent of fetal gender, and has the potential for non-invasive prenatal diagnosis of paternally inherited conditions.  相似文献   
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Prenatal diagnosis of 5p deletion syndrome, or cri du chat, following an abnormally low measurement of a screening of serum human chorionic gonadotrophin (hCG), is reported. Karyotyping following amniocentesis revealed a terminal deletion in the short arm of one chromosome 5. The pregnancy was electively terminated. 5p deletion syndrome has been described with abnormally high hCG levels and normal hCG levels. This is the first report of its association with abnormally low levels. The association between chromosomal abnormalities and hCG is discussed. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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Between August 1989 and December 1991, 356 patients underwent first-trimester transvaginal amniocentesis (10–12 weeks). The same number of patients referred in the same period for mid-trimester amniocentesis (14–21 weeks) was matched also for maternal age and indication. A third group consisted of the first 356 cases in which chorionic villus sampling (CVS) was attempted. The overall success rate was 99·7 and 100 per cent for early and mid-trimester amniocentesis, respectively, and 97·2 per cent for CVS. The mean harvesting time was 12·8, 11, and 7·9 days, respectively. The percentage of patients rescheduled was 3·4 per cent in first-trimester amniocentesis, 1·7 per cent in mid-trimester amniocentesis, and 6·2 per cent in the CVS group. The early (less than 2 weeks) pregnancy loss was 1·7 and 0·6 per cent in early and mid-trimester amniocentesis, respectively, and 1·7 per cent in CVS. The total pregnancy loss was 3·2, 0·9, and 2·9 per cent, respectively. The rate of preterm birth was 6·0, 5·2 and 6·9 per cent, respectively. The results indicate that CVS has the shortest procedure-result interval, but the highest rescheduling rate. First-trimester amniocentesis has a higher procedure and laboratory success rate but, until otherwise proved, mid-trimester amniocentesis is the most efficient and safest procedure.  相似文献   
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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   
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Natural mineral dust storms (DS) from the Arabo-African region blow over the Mediterranean, reach Israel, and add to the anthropogenic particulate pollution. The effects of mineral dust on air quality in Israel were investigated using only PM10 and PM2.5 automatic measurements. The method does not require any other inputs such as satellite observations, model back-trajectories, dust forecast models, or mineralogical analyses. The method employs an automatic algorithm with three thresholds: the half-hour PM10 average must be above 100, this level is maintained for at least 3 h, and the maximum concentration recorded is above 180 μg m?3. The algorithm was designed for Israel, but can be adapted for other locations.The contribution of DS caused PM10 values to exceed the Israeli annual standard of 60 μg m?3 year?1 in 6 of the 12 years examined. The DS contribution to PM10 annual average ranged from 9.4% to 29.5%. The level recommended by WHO, 20 μg m?3 year?1, was exceeded every year even without the DS contribution. The number of days in which the daily Israeli standard (150 μg m?3) was exceeded during the 12 years was 6–20 days per year. The number of days in which the daily standard was exceeded shows an increasing trend of 7 days per decade.PM2.5 in Israel is in the range 40–56% of PM10. PM2.5 values were over the recommended standard with and without DS. The contribution of DS to annual average of PM2.5 ranged from 3.6% to 19.1%.The automatic algorithm was calibrated with a list of Dust Storms identified by visual means supported by mineralogical analysis. Mineralogical analyses of single particles were performed using Environmental Scanning Electron Microscope (ESEM). Two representative samples are given. The main difference is that the particles of the Saudi-Arabian storm had much more palygorskite, while the North-African storm had more sea-salt and organic particles. The mineral composition differences indicate that analysis can differentiate between sources.  相似文献   
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