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101.
Pyruvate dehydrogenase (PDH) E1α subunit deficiency is an X-linked inborn error of metabolism affecting males and females with equal frequency. The diagnosis is usually based on determination of enzyme activity, although this may present difficulties in some females because of X-inactivation patterns favouring expression of the normal X chromosome. This is a particular problem for prenatal diagnosis using chorionic villus cells where normal enzyme assay results do not necessarily exclude the diagnosis and confirmatory X-inactivation analysis may be complicated by variable methylation of active and inactive X chromosomes. We describe prenatal diagnosis in two pregnancies in a family following diagnosis of a PDH E1α deficient male. The first prenatal diagnosis was performed by enzyme assay, but by the time of the subsequent pregnancy, the underlying mutation in the affected male had been identified and direct gene analysis was possible. This study highlights the limitations of diagnosis of PDH E1α deficiency based on measurement of the gene product and illustrates the need for mutation analysis in affected individuals.  相似文献   
102.
We report the prenatal diagnosis of two fetuses with Sanfilippo disease type B. In both pregnancies there were excessive amounts of heparan sulphate in amniotic fluid and the activity of N-acetyl-α-D-glucosaminidase was undetectable in cultured amniotic fluid cells. The predictions were confirmed by enzyme assay of cultured skin fibroblasts from the aborted fetus or the affected infant. The disorder was excluded for two other pregnancies at risk and the predictions are considered to be correct because of the normal progress of the healthy children.  相似文献   
103.
DetoxifyingmoniliforminingrainsandwaterZhangHong,LiJilunColegeofBiologicalSciences,ChinaAgriculturalUniversity,Beijing1000...  相似文献   
104.
Altemaria alternata were isolated from wheat seeds collected from villages in Tianshui area of Gansu Province where Kaschin-Beck disease is prevalent. TLC, IR and UV analyses of metabolic extract of A. alternata show that A. alternata produce main secondary metabolites, including alternariol, alternariol methyl ether, and tenuazonic acid.There was a significant decrease in Se-GSH-Px and SOD activities, and an acceleration in lipid peroxidation in rats fed with a diet containing metabolites produced by A. alternata.  相似文献   
105.
贝类典型寄生虫病害   总被引:2,自引:1,他引:2  
体内寄生的原生动物是海水养殖贝类最严重的病原生物之一,在国外已进行了比较系统的研究。本文比较详细地介绍了典型贝类体内寄生的原生动物病害,包括血细胞虫病、微细胞病、槌虫病、单孢子虫病、帕金虫病,对其分类的地位、形态结构、生活史、流行情况、危害机理等进行了论述,为我国贝类病害的研究和防治提供参考。  相似文献   
106.
A pregnant woman affected with autosomal dominant polycystic kidney disease (ADPKD) had a history of an affected fetus, diagnosed by sonography at 29 weeks of pregnancy. The proband's father was also affected. DNA analysis performed on chorionic villi at 11 weeks during a second pregnancy predicted an affected fetus, and sonographic examination at 14 weeks confirmed the diagnosis.  相似文献   
107.
108.
研究表明,在自然状态下,儿童大骨节病病情的变化是以人体硒营养变化为基础的骨质病变或修复的变化。早期病变的自然修复与人体发硒含量的升高同步发生,从而为用发硒含量定量地监测和预报病情提供了客观的指标。  相似文献   
109.
This paper describes a case of prenatal diagnosis for Wilson disease (WD) carried out in an at-risk couple of Sardinian descent, following non-directive genetic counselling. Diagnosis was obtained by using eight microsatellites located within or flanking the WD locus, six of which were 100 per cent and two 50 per cent informative. The use of several markers may limit the occurrence of misdiagnosis resulting from recombination or instability of repeats.  相似文献   
110.
The relation between EH [Se(VI)/Se(IV)] and pH of soil aqueous extract in Kaschin-Beck disease region and the effects of natural redox agents, namely humic substances, MnO2 and Fe2+, on the redox property of the system were studied. The results indicated that both humic acid and Fe2+ could enhance the reducibility of Se(VI) and MnO2, a limited oxidizability for Se(IV). Fe2+ showed a weak reducibility only at low pH value. The reducibilities of three sulfur-containing compounds for Se(VI) were in following order:thioglycollic acid > L-cysteine > sulfide  相似文献   
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