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排序方式: 共有771条查询结果,搜索用时 93 毫秒
701.
烟台市养虾废水排放及控制 总被引:6,自引:0,他引:6
本文通过对人工养殖对虾的生长过程中废水排水排放量及以COD为主要污染因子的污染物排放量的现场调查和则,基本摸清了对虾养殖业对烟台近海海域的污染贡献。同时结合当地实际情况,讨论了控制措施。 相似文献
702.
K. Toftager-Larsen R. J. Benzie T. A. Doran M. Miskin L. C. Allen L. Becker 《黑龙江环境通报》1983,3(1):35-40
Based on data from 5 cases of fetal cystic hygroma (4 cases of Turner's Syndrome and one case of Trisomy 18) and one case of Down's Syndrome with severe subcutaneous oedema, it is concluded that amniotic fluid alpha-fetoprotein (AFP) is normal or only slightly elevated in such cases whereas AFP in fluid from the cystic structures is very high. Reported high values of ‘amniotic fluid’ AFP are therefore likely to have been obtained from fluids accidentally drawn from the cystic structures. Fluids from the two sources cannot be distinguished from each other visually. In support of this theory is that the maternal serum AFP was found to be normal in all cases where investigated. In the diagnosis of cystic hygromata detailed ultrasound scanning will reveal the correct diagnosis. 相似文献
703.
海洋环境监测中有关分析空白值的探讨 总被引:6,自引:0,他引:6
作者根据对《海洋监测规范》论证过程中提供的有关数据的统计分析,提出了样品检出限应高于样品空白的2倍,测定限应高于样品空白的3倍。亦即,一般情况下样品的测定限应高于空白值的3倍,若样品的测定值低于空白值3倍时,测定值将不可靠。 相似文献
704.
Chorionic villi obtained during the first trimester from a pregnancy at risk for Krabbe's disease were shown to have reduced cerebroside-β-galactosidase (E.C. 3.2.1.46) activity using the artificial substrate trinitrophenylaminolauryl galactocerebroside (TNPAL-galactocerebroside). Assay of this enzyme in cultured amniotic fluid cells following amniocentesis, performed at the patient's request confirmed the diagnosis. Termination of pregnancy was performed and subsequent enzyme studies of the fetal tissues were consistent with the diagnosis of Krabbe's disease, thus confirming that chorionic villi can be used for first trimester diagnosis of this condition. 相似文献
705.
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
706.
Markku Heikinheimo Pertti Aula Juhani Rapola Torsten Wahlström Hannu Jalanko Markku Seppälä 《黑龙江环境通报》1982,2(2):103-108
Amniotic fluid levels of pregnancy-specific β1-glycoprotein (SP1) were elevated in four pregnancies with Meckel's syndrome at 16 and 26 weeks, and the levels of hCG were also elevated in three out of four cases. These findings suggest a potential new application of SP1 measurement for prenatal diagnosis. 相似文献
707.
Dr David A. Aitken Gary McCaw Jennifer A. Crossley Esther Berry J. Michael Connor Kevin Spencer James N. Macri 《黑龙江环境通报》1993,13(8):681-689
Alpha-fetoprotein (AFP), unconjugated oestriol (UE3), intact human chorionic gonado-trophin (intHCG), and the free β subunit of chorionic gonadotrophin (FβHCG) were investigated in a series of 21 chromosomally abnormal and 14 open neural tube defect pregnancies ascertained from a series of 14 000 prospectively collected maternal serum samples at 6–14 weeks' gestation. In 16 cases of Down's syndrome, significant reductions were found for AFP (0.65 multiples of the normal median) and UE3 (0.67 MOM). IntHCG levels were unaltered (0.97 MOM) but a significant increase was found for FβHCG (1.96 MOM). Significant correlations were found for AFP and UE3 in the controls and for int HCG and FβHCG in both the control and the Down's syndrome pregnancies. In a group of five trisomy 18 pregnancies, median MOMs were for AFP 0. 71 , for UE3 0. 34 , for intHCG 0. 27 , and for FβHCG 0.15. None of 13 pregnancies with open neural tube defects at 8-13 weeks gestation had elevated maternal serum AFP levels, whereas matched second-trimester samples from the same pregnancies at 16-18 weeks gestation all had significantly elevated AFP levels. Thus, biochemical screening for chromosome abnormalities may be practicable in the first trimester using free β human chorionic gonadotrophin in combination with AFP and maternal age. However, a separate screening protocol using AFP at 15-18 weeks gestation would still be required for effective detection of neural tube defects. 相似文献
708.
S. Eliyahu N. Yanai O. Blondheim D. Reich L. Siplovich E. Shalev M.D. 《黑龙江环境通报》1994,14(12):1170-1172
Prenatal sonographic presentation of Hirschsprung's disease has been considered non-specific and uncommon. This report presents a second-trimester fetus with an aganglionic colon and ileum diagnosed by the sonographic presentation of dilated fetal bowel loops, increased abdominal circumference, and mild polyhydramnios. The prenatal sonographic diagnosis of Hirschsprung's disease helped to expedite early neonatal treatment. 相似文献
709.
本文从摩尔吸光系数ε出发,推算出分子吸收分光光度法中校准曲线的斜率b0,并确定出斜率值的允许范围。通过对我站历次所做校准曲线进行研究,发现它们的斜率范围与本文所确定的范围符合得较好。 相似文献
710.
For the last 6 years, sonographic signs for excessive fluid accumulation in the backs of 10- to 12-week-old fetuses have been looked for prior to transabdominal chorionic biopsy. In 1400 pregnancies, subsequent karyotype analyses revealed 28 cases of Down syndrome. In 15 ( = 54 per cent), a large fluid cushion over most of the back had been documented at the time of biopsy. Only a few chromosomally normal fetuses with the same peculiarity were observed. The cushion was also present in fetuses with trisomies 18 and 13 , and in Turner syndrome. Systematic first-trimester screening for nuchal fluid accumulation seems to be a recommended method for the detection of Down syndrome and other chromosome anomalies in young pregnant women at low risk. It compares favourably with current methods of maternal serum screening performed at 16–18 weeks which require a higher number of invasive procedures. 相似文献