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561.
室内空气品质评价及相关研究 总被引:5,自引:0,他引:5
介绍国内外有关室内空气品质的研究成果 ,包括IAQ影响因素 ,卫生标准和评价。 相似文献
562.
Congenital nephrosis of the Finnish type (CNF) is rare outside Finland, where the incidence may be as high as 1 in 2000 live births. Neonates with the disorder develop renal failure within the first months of life and without renal transplantation, the prognosis is extremely poor. This case report describes a woman's three pregnancies, two of which were affected with CNF. 相似文献
563.
Iduronate sulphatase activity was determined in uncultured chorionic villi from four fetuses at risk for Hunter syndrome. AH fetuses were shown to be female by chromosome analysis. Biopsy material from three fetuses showed iduronate sulphatase activity within normal limits whilst the fourth fetus showed activity reduced to 7 per cent of our control mean. The importance of fetal sexing in prenatal diagnosis of this condition is emphasized as female carrier fetuses may show iduronate sulphatase activity reduced to levels observed in affected males. 相似文献
564.
Prenatal morphology of Meckel's syndrome was studied in five fetuses of different gestational age, that had been aborted because ultrasonography and elevated amniotic AFP-levels indicated neural tube defect. Histologically, the enlarged polycystic kidneys were completely alike with respect to the type of involvement and differed only in the severity of changes. They could be identified as type III cystic kidneys according to the classification of Potter. Proliferation of hepatic bile ducts and slight cystic dilatation of pancreatic ducts is already evident in the youngest fetus. Additional cyst formation in the epididymis was found in one of the cases. Occipital encephalocele, located within an apical occipital bone defect was always associated with a second mostly occult encephalocele protruding through a separate defect of the basal occipital squame and of the first and second vertebral arch. It is assumed that double encephalocele represents a constant finding in Meckel's syndrome, indicating a specific pattern within the disturbance of neural tube closure. 相似文献
565.
对虾白斑综合症杆状病毒越冬宿主的研究 总被引:1,自引:0,他引:1
实验结果表明:在冬季即将放水干枯的虾塘中,携带WSBV的厚蟹可达15%,其中在88.9%的病蟹能活至翌年春天,并引起新的白斑综合症爆发。用患白斑综合症的斑节对虾投喂厚蟹和虎头蟹,只能引起40%的死亡率。用发病虾塘的幼厚蟹投喂斑节对虾,在6d内引起死亡率达73.9%,死亡的斑节对虾具有典型的白斑综合症病征。根据研究的结果,我们认为厚蟹是WSBV的越冬宿主。 相似文献
566.
The prenatal diagnosis of thrombocytopenia absent radius syndrome in both dizygotic twins utilizing ultrasound, radiography and fetoscopy is described. 相似文献
567.
J. M. M. Van Lith A. Mantingh H. W. A. De Bruijn For the Dutch Working Party on Prenatal Diagnosis 《黑龙江环境通报》1993,13(12):1123-1131
We measured the maternal serum cancer antigen 125 (MS-CA 125) levels in 98 nonpregnant women, 765 first- and second-trimester pregnancies with chromosomally-normal fetuses, and 54 chromosomally-abnormal pregnancies. To determine the MS-CA 125 concentration, we used a new automated microparticle enzyme immunoassay with low inter-assay variability. The median MS-CA 125 level decreased from the first to the second trimester of pregnancy and was higher than that in non-pregnant women. We found no difference between normal and Down's syndrome (n = 29) pregnancies ( t-test: t = 0·57, p >0·5). The MS-CA 125 levels in pregnancies with other chromosomal abnormalities showed no difference either, compared with the normals. We conclude that MS-CA 125 is not a useful marker for fetal Down's syndrome, nor for other chromosomal disorders in pregnancy. 相似文献
568.
Catherine Donner MD Jean-Christophe Noel Françoise Rypens Jean van Kerkem Freddy Avni Frédéric Rodesch 《黑龙江环境通报》1995,15(1):60-63
A 29-year-old woman was referred for suspicion of twin-twin transfusion syndrome (TTTS). Several ultrasonographic and neonatal criteria of TTTS were encountered in this twin pregnancy. The peculiar observations in this case were, firstly, the demonstration of superficial anastomosis by Doppler ultrasound and, secondly, that one single therapeutic amniocentesis could have been sufficient to partially correct the progression of the syndrome, as after amniocentesis it was no longer possible to demonstrate the vascular communication. This observation suggests that superficial anastomoses could also have a role in the genesis of TTTS. Their effect could be monitored by Doppler ultrasound and could be more easily corrected by therapeutic amniocentesis. 相似文献
569.
We compared the medical and financial cost-effectiveness of prenatal serum screening for Down's syndrome using maternal age, serum alpha-fetoprotein and human chorionic gonadotrophin with and without the use of unconjugated oestriol. The use of unconjugated oestriol is medically more cost-effective than screening without it at all levels of detection. The actual performance depends on whether gestational age is estimated using ‘dates’ or an ultrasound scan. At a detection rate of 60 per cent, the proportion of unaffected fetal losses per case diagnosed at amniocentesis is about 22 per cent less if gestational age is estimated using dates (time since the first day of the last menstrual period) and about 47 per cent less if it is based on an ultrasound scan examination. At this detection rate, the inclusion of unconjugated oestriol increases costs by about £2k per case diagnosed (£36k instead of £34k) if gestational age is estimated using dates, but it is no more expensive if gestational age is measured from an ultrasound scan examination (indeed, it is more cost-effective at detection rates above 60 per cent). Since there is little change in the financial cost with the inclusion of unconjugated oestriol, for the improved medical performance of screening, it is worthwhile including it in the screening test. 相似文献
570.
Prenatal transvaginal diagnosis of the ectrodactyly,ectodermal dysplasia,cleft palate (EEC) syndrome
Transvaginal ultrasonography performed at 14 weeks' gestation demonstrated a bilateral cleft lip and lobster-claw deformities of the hands and feet, in keeping with the diagnosis of EEC syndrome (ectrodactyly or lobster-claw deformity, ectodermal dysplasia, and cleft lip and palate). The fetus was aborted and the diagnosis of EEC syndrome was confirmed. 相似文献