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321.
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   
322.
Prenatal diagnosis of Tay-Sachs disease was performed using the sulphated substrate 4- methylumbelliferyl-6-sulpho-2-acetamido-2-deoxy-β-D-glucopyranoside to detect hexosaminidase A in chorionic villi. The presence or absence of hexosaminidase A in villi was detected by both a quantitative enzyme assay, and by a rapid, novel procedure which permitted visual discrimination between normal and affected villi.  相似文献   
323.
A 38-year-old lady, who had a previous infant with type 2 Gaucher disease, underwent prenatal diagnosis by chorionic villus sampling at 9 weeks' gestation. Results on the fresh villus revealed a 47,XY,+21 karyotype and a marked deficiency (2 per cent of control) of β-glucosidase activity. Following termination, villus material was cultured which initially revealed only a partial enzyme deficiency and a normal female karyotype, i.e., maternal cells. A subsequent culture contained 47,XY, + 21 cells which were deficient in β-glucosidase activity, thus confirming the diagnosis. The results in this interesting case illustrate the potential dangers of maternal cell contamination in cultured villus cells.  相似文献   
324.
The accuracy of biochemical and molecular prenatal diagnoses using chorionic villi as the fetal source was assessed by seven centres participating in the NICHD collaborative study on the safety and accuracy of chorionic villus sampling (CVS) and amniocentesis. Of 601 pregnancies studied, biochemical methods were used to determine the diagnosis in 283 fetuses at risk for 35 different metabolic disorders. Fifteen different lysosomal storage diseases accounted for 81 per cent of the biochemical prenatal diagnoses performed, with 57 per cent of these pregnancies at risk for Tay-Sachs disease. No errors were made in the biochemical diagnoses that predicted affected or unaffected fetuses. However, the diagnoses of certain disorders (e.g., mucopolysacchariodosis type IH, metachromatic leukodystrophy, and Krabbe disease) occasionally required confirmatory studies in cultured amniocytes because the enzyme results were inconclusive in direct and/or cultured villi or due to the presence of a pseudodeficiency allele. Of these, only the diagnosis of a fetus at risk for Krabbe disease remained inconclusive after special studies to discriminate between mutant and pseudodeficiency alleles. Recombinant DNA techniques were used to predict the diagnosis of 318 fetuses at risk for 16 different disorders in which the defective disease gene could be detected either directly or by linkage analysis to a nearby polymorphic marker. Of these, 32 per cent were for haemoglobinopathies, 25 per cent for cystic fibrosis, 24 per cent for Duchenne or Becker muscular dystrophy, and 7 per cent for haemophilias. Pregnancies at risk for known disorders with specific molecular lesions (e.g., sickle cell disease) were accurately diagnosed in direct and/or cultured villi. Diagnoses requiring analyses with closely linked polymorphic markers were occasionally uninformative or inconclusive. Maternal contamination was not reported in any biochemical or molecular-based diagnosis. These studies document the high accuracy and rapidity of both biochemical and mutation-specific prenatal diagnoses with direct and cultured chorionic villi.  相似文献   
325.
For prevention and treatment of Kaschin-Beck disease by applying Se fertilizer to soil to increase Se up to normal level for the wheat grains is introduced in this paper. After use this measure the intake of Se by the residents in the exemplary area increased from 10.4μg to 33.6 μg per day in average. After supplementing Se to human body one year, there is no new patient found among 300 healthy children in the exemplary area but 4 patients found among 264 healthy children in the control area. It is shown that by applying Se fertilizer to KBD area is a effective way for preventing and cure this disease.  相似文献   
326.
A prenatal diagnosis was carried out on a 9-week-old fetus at risk for autosomal dominant polycystic kidney disease (ADPKD). Ten members of the family were previously typed using five DNA markers linked to the PKD1 locus on chromosome 16, and one marker linked to the putative PKD2 locus on chromosome 2. The polymerase chain reaction (PCR) was used to amplify the D16S125 locus. Pairwise and multipoint lod scores indicated that the family was most likely segregating a PKD1 mutation. The fetus inherited the disease haplotype from the affected parent. Diagnostic accuracy was greater than 99 per cent, taking into account the possibility of genetic heterogeneity.  相似文献   
327.
Before 1970s the Second Songhua River and Ji Canal of China had been polluted seriously by mercury. During peak pollution period, mercury levels in water, sediment and fish body of these rivers were close to or even higher than that of famous Minamata Bay of Japan. Some residents who live near to the polluted rivers were affected and the methyl mercury values in their blood, hair and urine were higher than normal people obviously . Since the fish had decreased even vanished in these rivers, so the food chain that transfers mercury to human also was out off almostly. However, nervous symptoms of Minamata disease were discovered among fisherman who had eaten more fishes. This report relates the stories about the mercury pollution of the Second Songhua River and Ji Canal.  相似文献   
328.
The relationship between humic acid and selenium content was studied in this research. The results of calculation showed that there is more humic acid and less selenium in Kaschin-Beck disease areas in China. Fulvic acid in soil could increase selenium level in plants. The chemical bonding between humic acid and selenium was observed with an I.R. spectroscope. It was remarkable for the changes of absorption peak and frequency in 1100-1000 cm-1, 900-700 cm-1.  相似文献   
329.
It is generally recognized that the sonographic findings of infantile polycystic kidney disease (IPKD) are bilaterally enlarged kidneys, oligohydramnios, an absent fetal bladder, and the typical kidney texture. Since there is a broad spectrum of renal compromise with IPKD, in utero diagnosis is thought to be limited to the severe forms. This paper reports a mild case of IPKD, where the in utero diagnosis was established by measuring fetal urine production and amniotic fluid volume serially during pregnancy, and by ultrasonographic examination of fetal kidneys.  相似文献   
330.
酸尘降地区酸雨难在短期内单独致使水体和土壤酸化。降尘对土壤--蔬菜中的SO4^2-、NO3^-、Ca^2+和Hg有较大贡献。随着降尘量的增加,对应土壤中的全S、吸附态S和Hg含量也相应增加,表现出高度下相关,但未达显著水平;NO3表现为中度相关,Ca^2+表现为弱相关。降尘土促进酸寸对蔬菜的危害,主要表现多病害,且伴有虫害发生,蔬菜宜种度变窄,对酸沉降敏感的青菜、蕃茄等几乎绝种。钙质土对降尘和酸雨  相似文献   
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