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11.
Two linked probes were used to determine the Huntington's disease status of the fetus conceived by a woman affected with the condition. The fetus was found to be unaffected with a certainty of 97 per cent. The ethical issues associated with presymptomatic testing were avoided since the mother presented with initial symptoms of Huntington's disease, but other psychological and ethical issues arose. The concerns of an affected woman planning a pregnancy, and the dilemmas involved in decision-making regarding prenatal diagnosis and possible selective abortion were exposed and explored with the patient and her husband. 相似文献
12.
Mr Selwyn H. Roberts Elizabeth Little Merle Vaughan Michael R. Creasy Anthony Jones Teyrnon G. Powell Andrew J. Dawson 《黑龙江环境通报》1993,13(10):971-975
A woman in the 32nd week of pregnancy was referred for investigation because of fetal abnormalities, including an abdominal wall defect, detected by ultrasonography. In view of the increased risk of chromosome abnormality, amniocentesis was performed to enable informed decisions about the management of the pregnancy and delivery to be taken. Cells from the liquor were inoculated into standard lymphocyte culture medium and incubated for 72 h. Slides with a high mitotic index and good quality metaphases, comparable to those from a blood culture, were obtained after harvesting. Cytogenetic analysis showed the karyotype to be 46,XY,—14,+t(13ql4q), which is consistent with Patau's syndrome. This technique appears to be an option for rapid karyotyping in cases of abdominal wall defect, where a chromosomal abnormality is suspected. 相似文献
13.
渤海江豚组织中钠,钙,锶,镁,磷,钾的研究 总被引:3,自引:0,他引:3
1990年,作者于辽东湾采集了10头江豚标本,分别测定了其骨骼、皮肤、肌肉、肝脏、肺、肾、心、胃、肠、胰、脾、肾上腺及生殖腺等13种组织中Ca、Sr、Mg、P、K、Na6种元素的含量,详细分析了骨骼及其他各组织中的Ca/Mg值、Ca/K值、Ca/P值、Ca/Na值和Ca/Sr×100值。结果表明,Ca、Sr、Mg、P,K在骨骼中累积率最高,钾在肌肉中具有高累积,Sr、Ca在肌肉中累积率最低;Mg累积率最低的组织是生殖腺,P累积率最低的组织是肠,而K在骨骼中,Na在肌肉中的累积率均高于其他组织。分析结果还显示,Ca/Mg值最高的是骨骼,最低为肌肉,Ca/P值最高的是骨骼,最低的是肌肉和胰脏,Ca/K值最高为骨骼,最低为脾Ca/Sr×100值最高为肺、最低为肠,而K/Na值最高为肌肉,最低为骨骼,在骨中Ca/P值大约为1,类同于猫和人类。 相似文献
14.
Hurler's disease was excluded in a fetus at 23 weeks' gestation by demonstrating normal iduronidase activity in fetal leucocytes following failure of amniotic cell culture after amnic-centesis at 16 and 19 weeks' gestation. The diagnosis was confirmed in the neonate. 相似文献
15.
A mother affected with Apert's syndrome was diagnosed by ultrasound scan at 16–17 weeks to have a fetus similarly affected. The typical features of acrocephaly and symmetrical syndactyly were seen. This is probably the first time that this condition has been diagnosed at such a gestation by ultrasound scan. The patient decided to continue the pregnancy, and intrauterine death occurred at 34 weeks. The diagnosis was confirmed by pathological examination. 相似文献
16.
本文主要介绍了用~(210)Pb─~(210)Bi法测定海洋现代沉积速率和数据处理方法的研究。该方法测定的结果与~(210)Pb─~(210)Po法和阴离子交换-EDTA纯化-硫酸钡镭沉淀-α计数法(简称~(226)Ra法)以及厦门大学海洋系经研究改进的分离、纯化~(210)Pb的离子交换法的测定结果相当吻合。 相似文献
17.
A study for the photochemical behavior of some polyaromatic hydrocarbons (PAH), for example B(a )P, B( k )F and fluoranthene in coal smoke particles was performed by using indoor Teflon smog chamber.Experiments suggest that the photochemical reaction of PAH is first order reaction and kinetic rates of some PAH were obtained. It was shown that the reaction rate constant is proportional to light intensity and water vapor concentration. Temperature and PAH loading also have influence on PAH decay rate. A model for PAH loss has been set up on the basis of the results of our experiments and the simulating results of this model suggest that coal particle PAH half lives are of the order of a period of days in winter and a few hours in summer. Other factors which may have effect on the photochemical reaction of PAH have also been discussed. 相似文献
18.
重庆大气可吸入颗粒物中多环芳烃的分析测定 总被引:4,自引:0,他引:4
本文报告了重庆大气可吸入颗粒物(IP)中多环芳烃(PAH)的分析测定方法和结果.用GC-MS定性和定量分析了重庆IP中的PAH;研究了IP中PAH的种类和分布情况;确认重庆IP中存在甲基多环芳烃(MePAH)、约占33%;颗粒大小分布表明,约有98%PAH存在于小于3μm的颗粒中. 相似文献
19.
海域有机污染物优先排序和风险分类模糊评判系统 总被引:1,自引:2,他引:1
本文提出了对区域性有机污染物优先排序和风险分类和定量评判系统:模糊评判系统。该评判系统以反映污染物的毒性,暴露水平和环境化学性质的7项碜数为指标,通过指标参数的标准化及模糊运算,获得有机污染优先排序和风险分类的定量结果。 相似文献
20.
The de-O-sulphation of α-linked glucosamine-6-sulphate residues in heparan sulphate requires a specific sulphatase, glucosamine-6-sulphatase, which has been shown to be deficient in tissues of Sanfilippo D, or mucopolysaccharidosis type IIID (MPS IIID), patients. MPS IIID fibroblasts cultured in Basal Eagle's medium supplemented with either fetal calf serum or heat-inactivated fetal calf serum, MDCB or Ultraserg media had residual glucosarnine-6-sulphatase activities towards a heparin-derived trisaccharide substrate, O-(α-N-acetylglucosamine-6-sulphate)-(1→4)-L -O-(α-iduronic acid-2-sulphate)-(1→4)-D -O-2,5-anhydro [1-3H]mannitol-6-sulphate, GlcNAc6S-IdoA2S-anM6S, which were less than 1 per cent of the normal range for fibroblasts cultured in Basal Eagle's medium supplemented with fetal calf serum. However, the glucosamine-6-sulphatase activities of MPS IIID fibroblasts grown in Chang's medium were similar to the activities in normal control fibroblasts which were cultured in Basal Eagle's medium. These results indicate that caution is required for prenatal diagnosis of MPS IIID patients using chorionic villi or amniotic cells cultured in Chang's medium. 相似文献