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大骨节病软骨基质代谢异常与硒的关系的探讨

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甘肃医药 1985年第2期 3-5页

作者：徐吉敏甘肃省地方病防治研究所

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不同形式硒在人体的代谢

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国外医学（医学地理分册） 1994年第4期15卷 173页

作者： Whanger-P 谭武红译

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GLUTATHIONE PEROXIDASE-ACTIVITY OF GLUTATHIONE-S-TRANSFERASES PURIFIED FROM RAT-LIVER

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BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 1977年第2期76卷 437-445页

作者： PROHASKA, JR GANTHER, HE UNIV WISCONSIN DEPT NUTR SCI MADISON WI 53706 USA

Gel filtration chromatography demonstrated the presence of 2 peaks of glutathione peroxidase activity assayed with cumene hydroperoxide in the soluble fraction of rat liver, brain, kidney and testis. The peak with a MW of .apprx. 45,000 (GSH-Px II) was purified from rat liver labeled in vivo with Na275SeO3. Chromatography on DEAE-cellulose, Sephadex G-150, DEAE-cellulose and CM-cellulose resulted in the co-purification of glutathione-S-transferase activity measured with 1-chloro-2,4-dinitrobenzene and glutathione peroxidase activity assayed with cumene hydroperoxide, and in the removal of all detectable 75Se. Studies on GSH-Px II indicated that the apparent Km for both cumene and tert-butyl hydroperoxides was considerably higher than that for purified seleno-glutathione peroxidase. The Vmax estimated with cumene hydropeptide was only 1/300 of that determined for the selenoenzyme at pH 7.5 and with 1 mM GSH.

关键词：脑/酶学二硝基苯类/代谢谷胱甘肽过氧化酶/分离和提纯谷胱甘肽过氧化酶/代谢谷胱甘肽转移酶/分离和提纯谷胱甘肽转移酶/代谢肾/酶学动力学肝/酶学分子量过氧化物酶类/代谢过氧化物/代谢硒/代谢睾丸/酶学动物男(雄)性大鼠

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Selenium metabolism in Drosophila -: Characterization of the selenocysteine tRNA population

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JOURNAL OF BIOLOGICAL CHEMISTRY 1999年第26期274卷 18729-18734页

作者： Zhou, X Park, SI Moustafa, ME Carlson, BA Crain, PF Diamond, AM Hatfield, DL Lee, BJ Seoul Natl Univ Inst Mol Biol & Genet Genet Mol Lab Seoul 151742 South Korea NCI Sect Mol Biol Selenium Lab Basic Res NIH Bethesda MD 20892 USA Univ Utah Dept Med Chem Salt Lake City UT 84112 USA Univ Illinois Dept Human Nutr & Dietet Chicago IL 60612 USA

The selenocysteine (Sec) tRNA population in Drosophila melanogaster is aminoacylated with serine, forms selenocysteyl-tRNA, and decodes UGA. The K-m of Sec tRNA and serine tRNA for seryl-tRNA synthetase is 6.67 and 9.45 nM, respectively. Two major bands of Sec tRNA were resolved by gel electrophoresis, Both tRNAs were sequenced, and their primary structures were indistinguishable and colinear with that of the corresponding single copy gene. They are 90 nucleotides in length and contain three modified nucleosides, 5-methylcarboxymethyluridine, N-6-isopentenyladenosine, and pseudouridine, at positions 34, 37, and 55, respectively. Neither form contains 1-methyladenosine at position 58 or 5-methylcarboxymethyl-2'-O-methyluridine which are characteristically found in Sec tRNA of higher animals. We conclude that the primary structures of the two bands of Sec tRNA resolved by electrophoresis are indistinguishable by the techniques employed and that See tRNAs in Drosophila may exist in different conformational forms. The Sec tRNA gene maps to a single locus on chromosome 2 at position 47E or F, To our knowledge, Drosophila is the lowest eukaryote in which the Sec tRNA population has been characterized to date.

关键词：细胞培养的染色体图密码子黑腹果蝇/遗传学黑腹果蝇/代谢电泳聚丙烯酰氨凝胶 RNA 转移氨基酸特异/代谢硒/代谢爪蟾属动物

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USE OF DIETHYLDITHIOCARBAMATE FOR QUANTITATIVE-DETERMINATION OF TELLURITE UPTAKE BY BACTERIA

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ANALYTICAL BIOCHEMISTRY 1992年第2期204卷 292-295页

作者： TURNER, RJ WEINER, JH TAYLOR, DE UNIV ALBERTA DEPT MED MICROBIOL & INFECT DISEDMONTON T6G 2H7ALBERTACANADA UNIV ALBERTA DEPT BIOCHEMEDMONTON T6G 2H7ALBERTACANADA

We have developed a simple method for the quantitative determination of tellurite in biological media. This assay is suitable for studying tellurite uptake in bacteria and overcomes the problems of older techniques which are time consuming and labor intensive. In earlier protocols diethyldithiocarbamate was reacted with tellurite and the resulting complex was extracted into organic solvents before spectrophotometric determination. In this study, diethyldithiocarbamate was incubated with tellurite at neutral pH to form a yellow colloidal solution. The absorbance of the aqueous yellow sol was used to determine tellurite concentrations in the range of 1 to 50 micrograms/ml (4 to 200 microM) without the need for solvent extraction.

关键词：砷/代谢亚砷酸盐类生物转运二硫代氨基甲酸酯/诊断应用大肠杆菌/代谢氢离子浓度质粒硒/代谢光谱分析碲/分析碲/代谢

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SELENIUM IN RUMINANT NUTRITION - REVIEW

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JOURNAL OF DAIRY SCIENCE 1975年第10期58卷 1561-1577页

作者： AMMERMAN, CB MILLER, SM UNIV FLORIDA DEPT ANIM SCI GAINESVILLE FL 32611 USA

The early interest in selenium related primarily to its toxicity, but since 1957 the element has been recognized as a dietary essential. The dietary requirement for selenium by most species is about .1 ppm. Deficiencies of selenium in cattle and sheep have been confirmed under natural grazing conditions in many countries of the world. Overt signs of inadequacy such as white muscle disease (nutritional muscular dystrophy) occur primarily in young calves or lambs born to selenium deficient dams. Infertility has increased in ewes grazing pastures low in selenium. In general, signs of deficiency have not occurred in older animals such as finishing beef cattle and lactating dairy cows. Subclinical deficiencies of selenium are not determined easily, however, and thus an inadequacy of the element may be limiting maximum animal performance under certain circumstances of drylot feeding. The current nutritional status of ruminant animals in many geographical areas and involving various feeding programs with this element has not been established. The recent widespread deficiency problems with nonruminants suggest that such an assessment should be made. Concentration of selenium in tissue, particularly in the liver, has been used in establishing selenium status of the animal. With lambs glutathione peroxidase activity in certain tissues may be a more accurate indicator of selenium adequacy than is selenium content of the tissue. Supplemental sodium selenite and sodium selenate by either oral administration or parenteral injection have prevented clinical signs of selenium deficiency and animal losses in both ruminant and nonruminant animals. Heavy pellets containing elemental selenium for placement in the rumen have proved effective. In general, organic forms of selenium are absorbed more readily by animals than are inorganic compounds. The dietary requirements for selenium and its metabolism are influenced by many nutrient interrelationships, including its interactions with sul

关键词：动物饲料/分析牛/代谢牛疾病缺乏症/并发症缺乏症/兽医学谷胱甘肽还原酶/代谢泌乳肌营养不良动物/病因学营养需要妊娠并发症硒/代谢硒/毒性绵羊/代谢绵羊疾病美国动物女(雌)性妊娠

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EFFECT OF SELENIUM-COMPOUNDS ON SELENIUM CONTENT, GROWTH AND CYSTINE-S-35 METABOLISM OF SKIN FIBROBLASTS FROM NORMAL AND CYSTINOTIC INDIVIDUALS

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BIOINORGANIC CHEMISTRY 1976年第3期6卷 187-202页

作者： RHEAD, WJ SCHNEIDER, JA UNIV CALIF SAN DIEGO SCH MED DEPT PEDIAT LA JOLLA CA 92093 USA

Kidney samples from children with inborn metabolic disease, cystinosis contain 4 times more Se than kidney samples from normal individuals (p = 0.1). When cultured skin fibroblasts from cystinotic patients and normal controls are incubated in Se-D,L-methionine, Se-D,L-cystine, ***, Se-urea, selenite or in medium without added Se, only the cystinotic fibroblasts grown in Se-urea or selenite .**GRAPHIC**. contain more Se than the corresponding normal cells (p < 0.05). In both types of cultured fibroblasts, the order of descending toxicity per ppm Se is: Se-urea > Se-cystamine > Se-cystine .gtoreq. .**GRAPHIC**. .mchgt. Se-methionine. High (apparently toxic) concentrations of Se-urea and Se-cystamine lower the elevated intracellular free (nonprotein) cystine content of cystinotic fibroblasts to < 60% of control values;at lower concentrations, these compounds raise the cystine content of these cells to over 140% of control values. Appropriate concentrations of .**GRAPHIC**. Se-cystine and Se-methionine also elevate the free cystine content of cystinotic cells. During a 75 min incubation in 35S-cystine, the incorporation of 35S into the acid precipitable (protein) fraction of both cell types is significantly inhibited by Se-cystamine ($ 55% control;P < 0.05). The incorporation of 35S-cystine into glutathione is inhibited by Se-cystine (.apprx. 40% control) in both fibroblast types (P < 0.05). In cystinotic cells, Se-cystamine significantly reduces incorporation of 35S-cystine into the cystine pool (40% control) as does .**GRAPHIC**. (67% control;P < 0.05). Protein and glutathione synthesis in cystinotic fibroblasts are more strongly inhibited by Se-cystine and .**GRAPHIC**. respectively, than in normal fibroblasts (P < 0.05) Se compounds probably exhibit a different sequence of toxicity in fibroblasts than in the intact animal and some previously unreported metabolic effects (i.e., inhibition of glutathione synthesis) may contribute to their toxicity.

关键词：氨基酸类/代谢胱氨酸/代谢胱氨酸病/代谢成纤维细胞/代谢参考值硒/代谢皮肤/代谢人类

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The effect of bioaccumulated selenium on mortalities and deformities in the eggs, larvae, and fry of a wild population of cutthroat trout (Oncorhynchus clarki lewisi)

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ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2000年第1期39卷 46-52页

作者： Kennedy, CJ McDonald, LE Loveridge, R Strosher, MM British Columbia Minist Environm Lands & Pk Pollu Cranbrook BC V1C 6H3 Canada Simon Fraser Univ Dept Biol Sci Burnaby BC V5A Canada

To determine if elevated concentrations of waterborne selenium (Se), caused by coal mining, in the Elk River in southeastern British Columbia, may be causing reproductive or teratogenic effects in wild cutthroat trout (Oncorhynchus clarki lewisi), fertilized eggs from exposed and reference fish were raised in the laboratory. Eggs from each female were reared separately and the percent mortalities and deformities were related to the selenium content of the eggs. Selenium concentrations in females from the exposed site were highest in the liver (36.6 +/- 22.5 mu g/g dry weight, range: 18.3 to 114), followed by the eggs (21.0 +/- 18.3 mu g/g, range: 8.7 to 81.3) and the muscle (12.5 +/- 7.7 mu g/g, range: 6.7 to 41). Despite these elevated egg Se concentrations, there was no significant effect on fertilization;time to hatch;percent hatch;or egg, larvae, and fry deformities or mortalities. Reproductive failure and embryonic terata have been reported at much lower egg Se concentrations in other fish species. The lack of any toxic response in this study may be due to an evolved tolerance to higher tissue Se concentrations in a population of fish living in a seleniferous river system.

关键词：畸形药物性/病理学动物新生英属哥伦比亚幼虫大麻哈鱼属/胚胎学大麻哈鱼属/代谢卵子/病理学硒/代谢硒/毒性动物女(雌)性

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Controlled introduction of selenium into Chlorella cells

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Indian Journal of Experimental Biology 1998年第12期36卷 1286-1288页

作者： de, Alcantara, S. Lopes, C. Cerqueira Wagener, K. Institute of Chemistry Federal University of Rio de Janeiro Brazil.

Selenium (Se) is an important element in the antioxidant system of the human body, and Chlorella, well-known for its therapeutic effects, is the ideal carrier to offer it in the wanted organic form. The kinetics of Se absorption by growing algal cells and its distribution in the cells are studied using radioactive 75Se labelled solutions. There is a rapid Se absorption within the first few minutes at the cell surfaces where it is irreversibly fixed and cannot be absorbed by the human body. In the final state, reached after 24-48 hr, about 40% of the total fixed Se is inside the cells in the wanted organic-bound form.

关键词：小球藻属/代谢动力学硒/投药和剂量硒/代谢

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INFLUENCE OF DIETARY CALCIUM, SELENIUM, AND METHYLMERCURY ON EGGSHELL THICKNESS IN JAPANESE QUAIL

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BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1978年第1期20卷 135-142页

作者： STOEWSAND, GS ANDERSON, JL GUTENMANN, WH LISK, DJ CORNELL UNIV INST FOOD SCIITHACANY 14853

A high Ca, semi-purified diet promoted greater egg production with thicker shells in Japanese quail hens. 7 ppm of dietary Se depressed egg weights with no effect on eggshell thickness. The addition of 20 ppm of MHg to either a low or high Ca diet containing Se depressed both egg production and eggshell thickness. Se residues of liver, kidney, and brain in Se-MHg fed quail were significantly higher than in Se treated quail, probably reflecting the ability of Se to bind with Hg. CA, an enzyme required for the formation of the carbonate radical of Ca carbonate in egg-shells, was not reduced in the Se-MHg treated Japanese quail hens′ blood or oviducts.

关键词：碳酸钙/分析钙膳食/药理学碳酸酐酶类/代谢鹌鹑属膳食卵壳/分析甲基汞化合物/药理学生殖/药物作用硒/代谢硒/药理学时间因素动物女(雌)性

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