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11.
Carrier detection and prenatal diagnosis of alpha-thalassemia of Southeast Asian deletion by polymerase chain reaction 总被引:7,自引:0,他引:7
Summary Alpha-thalassemia of Southeast Asian deletion (-- SEA/) is very common in Southeast Asia. Homozygosity of this genotype is the major cause of Hb Bart's hydrops fetalis in Taiwan. With polymerase chain reaction using three oligonucleotide primers bridging the common deletion breakpoint, a DNA fragment of 194 basepairs (bp) was amplified in chromosomes with the-- SEA determinant and a DNA fragment of 287 bp was amplified in chromosomes without this deletion. In our pilot study including 8 normal subjects, 20 obligate carriers, and 11 homozygotes of the deletion, all the genotypes were determined and then confirmed by Southern blotting and DNA hybridization with globin gene probe. For prenatal diagnosis, 55 at-risk pregnancies were collected. Chorionic villus sampling was done in 51 cases and early amniocentesis was done in 4 cases. Fourteen cases (25.5%) were diagnosed as normal, 25 (45.5%) as heterozygotes, and 16 (29%) as homozygotes of -- SEA. All of the diagnoses were also confirmed as aforementioned. With polymerase chain reaction, the determination of the -- SEA deletion is straightforward and is much quicker and easier than with conventional Southern blotting and DNA hybridization. In areas with a high prevalence of -- SEA deletion, this method provides a rapid tool for carrier detection and prenatal diagnosis. 相似文献
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Lipid peroxidation in liver, plasma, and erythrocytes of rats chronically treated with ethanol 总被引:2,自引:0,他引:2
The effect of ingestion of water containing 20% ethanol for 1-2 months on lipid peroxide levels of liver, plasma, and erythrocyte was investigated in rats. Our results show that elevated plasma lipid peroxide levels and erythrocyte susceptibility to lipid peroxidation may reflect stimulated lipid peroxidation in rat liver following chronic ethanol ingestion. 相似文献
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Extracellular accumulation of lysine and threonine was investigated in modified whey permeate by using Brevibacterium lactofermentum ATCC 21086 and Escherichia coli ATCC 21151. Whey permeate was prepared from whey by membrane ultrafiltration, and lactose was hydrolyzed by treating permeate with HCl or β-galactosidase. The highest amount of lysine (3.3 g/liter) was produced from a mixture of acid-hydrolyzed whey permeate and yeast extract (0.2%). The highest amount of threonine (3.6 g/liter) was produced from a mixture of whey permeate, (NH4)2SO4 (1.4%), yeast extract (0.1%), and Na2CO3 (0.3%). 相似文献
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T S Ko 《Biochemical and biophysical research communications》1973,52(3):1051-1056
The absorbance (260 nm)-temperature profile of ribosomes from seeds of , in the temperature range of about 25 – 60° was observed to be biphasic. When r-proteins in ribosomes were dansylated by 5-dimethylamino-1-naphthalenesulfonyl chloride dispersed on celite (180 molecules of 5-dimethylamino-1-naphthalenesulfonyl chloride per one ribosome particle), each transition midpoint was lowered by 2 – 3° and the sharpness of the transition of each phase was increased. The result of the present work suggests discrete cooperative transitions of the conformation of r-RNAs in ribosomes and its control by r-proteins. 相似文献
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Antiserum был подготовлен противингибитор вируса haemagglutination (IVH)одна из эмбриона chorioallantoic мембр анныепутем иммун изации морских св инокЭто анти-инги битора в сыворотке заблокирован ингибирование IVH из chorioallantoicмембран в haemagglutination испытанияно ника кого влияния на ре цепторы эритроци товСыворотке кро] ви не влияет рост chorioallantoic мембраны клет ок инет нейтрализ овать воздействи е на вирус гриппа Она снизилась спо собность chorioallantoic мембр ан для adsorb вируса гри ппа, а также степен ь размножения вир усав такого рода тканиАвторы хоте ли бы поблагодари ть г-н Г. Ruttkay-Ne -палубе и для проведения эле ктрофореза меру ния. 相似文献
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