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排序方式: 共有266条查询结果,搜索用时 15 毫秒
101.
Mordechai Shohat MD Edna Akstein Bella Davidov Gad Barkai Cyril Legum Miriam David Hanna Dar Yitzhak Romem Aliza Amiel Hana Cohen Gideon Bach Ziva Ben-Neriah Ruth N. Sheffer Zvi Appelman Juan Chemke Pnina Zadka Tamy Zer Boleslaw Goldman 《黑龙江环境通报》1995,15(10):967-970
We investigated the contribution of different screening criteria to the prenatal detection of Down syndrome (DS) as well as other chromosomal anomalies in the Jewish population in Israel during 1990 and 1992. There was a significant decrease (P<0·03) in the incidence of DS live-births during 1992 (40:78 442) compared with 1990 (69:73 751) which paralleled a marked increase in total prenatal testing and in DS cases detected prenatally. Private laboratories, which perform amniocenteses mostly for women with a low risk of DS and without genetic counselling, had a significantly lower detection rate (1:917) compared with that of the genetic institutes, which following genetic counselling test both women ≥ 37 years of age (1:91) and women younger than 37 years (1:113). The detection of chromosomal anomalies other than DS was less affected by the reason for amniocentesis. Amniocentesis indicated by maternal serum marker screening of women younger than 37 years identified a greater number of chromosomal anomalies other than DS than amniocentesis based on age (≥37 years) alone (111:9604 versus 94:9810; P<0·06). Prenatal detection of DS is most effective when the indication for amniocentesis follows genetic counselling. The increasing use of maternal serum marker screening leads to a significant improvement in the positive detection rate of chromosomal anomalies other than DS in young women. 相似文献
102.
David Chitayat Robert W. Marion Linda Squillante Dagmar K. Kalousek Kiron M. Das MD Ph.D. 《黑龙江环境通报》1990,10(11):725-732
Since its introduction, prenatal diagnosis of chromosomal and metabolic disorder by mid-trimester amniocentesis has relied upon the use of a mixture of fetal cells obtained from amniotic fluid. Little knowledge has been gained in the sorting of these cells for diagnosis of tissue-specific disorders. In an attempt to determine the contribution of fetal colonic mucosal cells to the overall amniocyte population, we used the colonic epithelial-specific monoclonal antibody (MC-Ab) 7E12H12, IgM isotype. Specimens of the small intestine, colon, buccal mucosa, kidney, urinary bladder, and umbilical cord were obtained from electively aborted normal fetuses of 12–28 weeks' gestation. All of these specimens were examined with 7E12H12 by the immunoperoxidase technique. The MC-Ab reacted with the colonic epithelial cells but not with any of the other tissues. In addition, 40 amniotic fluid samples obtained from women between 16 and 18 weeks of gestation, who underwent amniocentesis because of advanced maternal age, were tested using a fluorescent activated cell sorter. Among the amniotic fluid specimens examined, 18·4 ± 10·3 percent cells reacted with 7E12H12. Double immunofluorescence studies revealed that all Mc-Ab-stained cells contained secretory component, confirming that they were epithelial in origin. All fetuses whose amniotic fluid was analysed had normal karyotypes and amniotic fluid alpha-fetoprctein levels that were also normal. This study demonstrates that cell-specific Mc-Ab can be used to detect colon cells in the amniotic fluid and that colon cells contribute significant numbers in the mixture of amniotic fluid cells. This technique could be helpful in the prenatal diagnosis of disorders in which the flow of amniotic fluid through the fetal intestine is impaired, such as cystic fibrosis, imperforate anus, Hirschsprung aganglionic megacolon, and intestinal atresia. 相似文献
103.
104.
Kinetic adsorption of application of carbon nanotubes for Pb(II) removal from aqueous solution 总被引:1,自引:0,他引:1
Nassereldeen A Kabbashi Muataz A Atieh Abdullah Al-Mamun Mohamed E S Mirghami MD Z Alam Noorahayu Yahya 《环境科学学报(英文版)》2009,21(4)
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
105.
Floods are the most common type of natural disaster in both developed and developing countries and have led to extensive morbidity and mortality throughout the world. Worldwide, over the past 30 years, flooding has claimed the lives of more than 200,000 people and affected more than 2.8 billion others. The impact of flooding on health varies among populations and depends primarily on vulnerability and the kind of event experienced. It severely disrupts livelihoods and has a significant impact on the health of pregnant women and children. In addition, it may exacerbate a range of negative psychological and physiological child and reproductive health outcomes. Awareness‐raising, education, and the issuing of warnings appear to be key initiatives to mitigate or prevent flood morbidity and mortality, especially among people living in low‐ and middle‐income countries. Agencies responding to emergencies also need to be more cognisant of the dangers, specifically those engaged in healthcare, nutrition, and water safety programmes. 相似文献
106.
Nerium oleanderL. (Oleander) leaves grown in Palermo city (Sicily, Italy) were collected from six sampling sites representing either areas of high traff{i}c and urbanisation density or areas far away from traffic (e.g. city gardens). Concentration of Al, Ba, Cr, Cu, Fe, Pb, Mg, Mn, and Zn were determined in leaf samples during two years. Multivariate analysis classified the sampling sites in four groups based on the metal content in vegetal leaves in agreement with traffic and human activity site. Many elements studied (Al, Ba, Fe, Mn Mg) arise from the soil composition and others such as Cr, Cu, Pb and Zn as pollutant of the soil. On the other hand, about 30% of Al, Fe Cr, Cu and Pb originate from aerial deposition on leaves. Although the results presented should be handled with caution N. oleandercan be considered as a means of assessing dust contamination in the urban environment. 相似文献
107.
The incidence of haemangiomas was ascertained by questionnaire in infants born to 578 consecutive CVS patients and 445 consecutive mid-trimester amniocentesis patients seen at a single institution between 1 January 1989 and 31 May 1991. The incidence of 7·4 per cent reported in the amniocentesis group was comparable to previous estimates of the incidence of haemangiomas in the general population. In contrast, a 21·1 per cent incidence, three-fold higher than that observed in the amniocentesis group, was observed among CVS-exposed infants (P<0·001). This increased incidence was largely confined to patients undergoing a transcervical procedure. No correlation was observed between the incidence of haemangiomas and gestational age at sampling, sample size, number of sampling attempts, or a history of bleeding following the procedure. 相似文献
108.
M. R. Ulm MD K. Chalubinski C. Ulm B. Plöckinger J. Deutinger G. Bernaschek 《黑龙江环境通报》1995,15(4):368-372
Recently, sonography of the fetal face has gained increasing importance in prenatal diagnosis. It is not yet clear whether sonographic depiction of fetal tooth germs would have an influence on the prenatal diagnosis of ectodermal dysplasia syndromes. During routine malformation screening, horizontal sections of fetal jaws were visualized and examined for tooth germs in 124 pregnant women following sonographic ‘facing’. Histological jaw sections of fetuses that had died in utero at various gestational ages were produced in order to examine the degree of correspondence between the sonographic and histological findings. At least four tooth germs were found in the jaws of all fetuses between 19 and 34 gestational weeks (n=104). Although jaw visualization was possible between 14 and 18 gestational weeks (n=20), the exact number and location of the tooth germs could not be determined. Assessment of tooth germs may become increasingly important, as aplasia of the tooth germs is one of the principal signs of various hereditary ectodermal diseases. 相似文献
109.
We analysed maternal serum human chorionic gonadotropin (hCG) in 16 pregnancies with fetal abdominal wall defects previously identified prenatally by elevated maternal serum alpha-fetoprotein (AFP) or at birth. The AFP levels had a mean of 6·38 MOM (range 0·34–15·65), as expected with these defects. The hCG levels had a mean of 1·82 MOM (range 0·23–4·11). The hCG levels in five pregnancies (31·25 per cent) were above 2·30 MOM. Elevated levels of hCG may be associated with fetal abdominal wall defects. 相似文献
110.
Early prenatal diagnosis of osteogenesis imperfecta at 14 weeks' gestation by transvaginal sonography is reported. An anencephalic fetus was found at autopsy, although on sonographic examination complete brain tissue had been observed. A possible explanation for these findings and theories on the pathogenesis of anencephaly are discussed. 相似文献