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Antioxidant Effect of Selenium-containing Glutathione S-Transferase in Rat Cardiomyocytes 被引量:1
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作者 YIN Li HAN Xiao +6 位作者 YU Yang GUO Xiao REN Li-qun FANG Jing-qi LIU Zhi-yi YAN Gang-lin WEI Jing-yan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期454-458,共5页
As one of the most important antioxidant enzymes, glutathione peroxidase(GPX) protects cells and tissues from oxidative damage, and plays an important role in cardiovascular and cerebrovascular injuries induced by o... As one of the most important antioxidant enzymes, glutathione peroxidase(GPX) protects cells and tissues from oxidative damage, and plays an important role in cardiovascular and cerebrovascular injuries induced by oxida- tive stress. The antioxidant effect of selenium-containing glutathione S-transferase(Se-GST), a mimic of GPX was investigated on rat cardiomyocytes. To explore the protection function of Se-GST in hydrogen peroxide(H202) chal- lenged rat cardiomyocytes, we examined malondialdehyde(MDA), lactate dehydrogenase(LDH), superoxide dismu- tase(SOD) and cell apoptosis. The results demonstrate exposure of rat cardiomyocytes to H202 for 6 and 12 h induced the significant increases of MDA, LDH and apoptosis rate of cardiomyocytes, but pretreatment of rat cardiomyocytes with Se-GST at 0.0005 or 0.001 unit/mL prevents oxidative stress induced by H202 with the decreases of cell apopto- sis. All the results hint Se-GST has antioxidant activity for oxidative stress challenged rat cardiomyocvtes. 展开更多
关键词 selenium-containing glutathione S-transferasese-GST) Cell apoptosis Cardiac myocyte Oxidative stress
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基于预测农作物Se含量构建富硒土地质量评价体系——以湖南龙山县为例 被引量:2
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作者 张俊 戴亮亮 +7 位作者 巩浩 彭志刚 许青阳 胡向荣 贺灿 吴文彬 陈伟 曾剑 《中国地质》 北大核心 2025年第1期362-371,共10页
【研究目的】硒(Se)是人体必需的微量元素之一。富硒土地和富硒农产品的开发利用成为了乡村振兴的重要实践,但仅根据土壤Se含量难以准确地指导地方政府进行富硒土地资源开发。【研究方法】本文以湖南省龙山县西北部作为研究区,基于1∶50... 【研究目的】硒(Se)是人体必需的微量元素之一。富硒土地和富硒农产品的开发利用成为了乡村振兴的重要实践,但仅根据土壤Se含量难以准确地指导地方政府进行富硒土地资源开发。【研究方法】本文以湖南省龙山县西北部作为研究区,基于1∶50000土地质量地球化学调查数据和全国土地调查成果数据探讨了水稻Se生物富集系数的影响因素,并据此建立了水稻籽实Se含量多元线性回归预测模型,结合耕地地力和环境质量提出了富硒土地质量评价体系。【研究结果】(1)研究区土壤Se含量为0.19~0.84 mg/kg,平均值0.48 mg/kg,水稻籽实Se含量为0.02~0.23 mg/kg,平均值0.10 mg/kg,水稻籽实富硒率为83%。(2)水稻籽实Se生物富集系数与土壤Cd、S和TC呈极显著负相关关系,相关系数分别−0.617、−0.452和−0.574。(3)区划结果显示,研究区以无公害富硒中高产耕地为主,面积占比78%,无公害中高产耕地和无公害低产耕地面积相对较小,面积分别占13%和4%;安全利用富Se耕地和谨慎利用耕地面积分别占4%和1%。【结论】在科学预测农作物籽实Se元素含量的基础上,本文构建了一种基于农作物富Se水平、耕地地力和环境质量的地块尺度富Se土地质量评价体系,对地方政府进行富Se土地资源开发利用具有重要参考示范意义。 展开更多
关键词 se水稻 预测模型 富硒土地 区划方法 土壤地球化学调查工程 龙山县 湖南省
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基于根伸长的典型叶类蔬菜Se生态风险
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作者 张忠恩 李湘凌 +3 位作者 赵燕 吴安云 卢新哲 魏迎春 《合肥工业大学学报(自然科学版)》 北大核心 2025年第3期369-375,394,共8页
为探究硒(Se)对叶类蔬菜的毒性效应,文章通过水培实验,以18种典型叶类蔬菜萌发期的相对根伸长(relative root elongation,RRE)作为评测终点,采用Log-logistic、Hormesis模型确定典型叶类蔬菜的EC_(20)、EC_(50),基于Burr-Ⅲ模型分析18... 为探究硒(Se)对叶类蔬菜的毒性效应,文章通过水培实验,以18种典型叶类蔬菜萌发期的相对根伸长(relative root elongation,RRE)作为评测终点,采用Log-logistic、Hormesis模型确定典型叶类蔬菜的EC_(20)、EC_(50),基于Burr-Ⅲ模型分析18种蔬菜Se敏感性差异并计算最大环境有害浓度(hazardous concentration for 5%of species,HC 5)。结果表明:部分蔬菜无Se兴奋效应,部分蔬菜具有Se兴奋效应,兴奋效应质量浓度范围为0.1~5.0 mg/L,Se对蔬菜RRE的兴奋效应和毒害性与蔬菜种类密切相关;品种大白菜中白(DBCZ)、生菜孔雀菜(SCKQ)和空心菜竹叶(KXCZ)表现出较强的Se耐性,而品种茼蒿板叶(THBY)、茼蒿圆叶(THYY)和苋菜圆叶(XCYY)表现出较强的敏感性。不同蔬菜的Se毒性阈值差异明显,EC_(20)和EC_(50)范围分别为0.48~10.59 mg/L和1.88~19.60 mg/L;兴奋效应显著影响蔬菜的剂量-效应关系,Se兴奋效应组的模型参数(最大与最小RRE差值a、毒害性变化速率b、EC_(20)和EC 50)平均值显著大于无兴奋效应组;保护95%蔬菜的20%效应毒性阈值(HC_(5)^(20))和50%效应毒性阈值(HC_(5)^(50))分别为0.29、1.20 mg/L,蔬菜种类对HC 5影响极大,敏感性品种缺失会导致HC_(5)显著提高,耐性品种缺失会一定程度上降低HC_(5)。 展开更多
关键词 物种敏感性分布 毒性阈值 叶类蔬菜
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Environmental behaviors of selenium in soil of typical selenosis area,China 被引量:9
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作者 LI Yonghua WANG Wuyi LUO Kunli 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期859-864,共6页
Daba Mountain area is one of the two endemic selenosis areas in China,which may relate with the environmental behaviors of selenium (Se) in soil.This study focuses on the concentraion and distribution of Se and its re... Daba Mountain area is one of the two endemic selenosis areas in China,which may relate with the environmental behaviors of selenium (Se) in soil.This study focuses on the concentraion and distribution of Se and its relationships with some other elements in natural soil in the area.The average concentration of Se in Daba Mountain soils was 14.3 times higher than the value cited for natural soil background worldwide,suggesting that soils in the region were contaminated by the element.The finding was confirmed... 展开更多
关键词 selenium se selenosis area geoaccumulation index soil profile
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Nano-selenium controlled cadmium accumulation and improved photosynthesis in indica rice cultivated in lead and cadmium combined paddy soils 被引量:8
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作者 Chengrun Wang Tingting Cheng +6 位作者 Haitao Liu Fangyun Zhou JifengZhang Min Zhang Xinya Liu Wenjun Shi Tong Cao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第5期336-346,共11页
Selenium nanoparticles(Se NPs) are less toxic and more biocompatible than selenite or selenate. However, studies involving spraying with Se NPs for reducing accumulation of cadmium(Cd) and lead(Pb) in rice grains have... Selenium nanoparticles(Se NPs) are less toxic and more biocompatible than selenite or selenate. However, studies involving spraying with Se NPs for reducing accumulation of cadmium(Cd) and lead(Pb) in rice grains have been rarely reported as yet. Herein, indica rice seedlings cultivated in Cd + Pb-spiked paddy soils(denoted as positive control) were sprayed with Se NPs sols for four times from tillering to booting stage. Compared to positive control, 50–100 μmol/L Se NPs downregulated Cd transporters-related genes such as Os LCT 1, OsH MA 2 and Os CCX2 in leaves and OsLCT1, Os PCR1 and Os CCX2 genes in node I at filling stage. Meanwhile, Se-binding protein 1 was distinctly elevated, involving the repression of Cd and Pb transportation to rice grains. Se NPs also differentially improved RuBP carboxylase and chlorophylls especially some key genes and proteins involving photosynthetic system. Besides, 25–50 μmol/L Se NPs diminished reactive oxygen species overproduction from NADPH oxidases whereas boosted glutathione peroxidase, reducing protein carbonylation in rice seedlings. However, the antioxidant isozymes and oxidatively modified proteins were slightly rebounded at 100 μmol/L. Se contents were noticeably elevated and confirmed to exist as selenomethionine in the rice grains following all the treatments by Se NPs. Thus, the optimal dosage of Se NPs for foliar application is 50 μmol/L, which significantly decreased Cd accumulation, improved photosynthesis and Se enrichment whereas caused no distinct reduction of Pb in the grains. Thus, an appropriate dosage of Se NPs can be conducted to decrease Cd accumulation, improve photosynthesis, and organic Se contents in rice grains. 展开更多
关键词 selenium nanoparticles(se NPs) Heavy metals Oryza sativa L. selenium enrichment and cadmium reduction Food quality and safety
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STUDY ON THE EFFECT OF T-2 TOXIN AND SELENIUM ON CD44 EXPRESSION IN THE CULTURED HUMAN FETAL CHONDROCYTES IN VITRO 被引量:2
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作者 谢龙 曹峻岭 +4 位作者 岳燕 朱建宏 张增铁 张富军 李思远 《Journal of Pharmaceutical Analysis》 SCIE CAS 2003年第1期78-81,共4页
Objective To investigate the effect on the structure of reestablished cartilage in vitro and CD44 expression on chondrocytes and compare the inducing effect on the reestablished cartilage in vitro between cor... Objective To investigate the effect on the structure of reestablished cartilage in vitro and CD44 expression on chondrocytes and compare the inducing effect on the reestablished cartilage in vitro between cortical bone matrix gelatin and cancellous bone matrix gelatin. Methods To plant human fetal chondrocytes on the BMG, the damage of the cultured chondrocytes was observed by the optical microscope (HE staining). The immunohistochemistry of CD44 was quantitative analysis by the image collection and analysis system. Results With the increasing concentration of T 2 toxin, the damage of chondroytes was more and more evident and CD44 expression was lowered. After adding selenium, the damage was relieved and CD44 expression increased. The density of chondrocytes on the cortical bone matrix gelatin was much higher than that on the cancellous bone matrix gelatin. Conclusion T 2 toxin can lower the CD44 expression on the chondrocytes and adding selenium can relieve the damage caused by T 2toxin and increased CD44 expression. The inducing effect on reestablished cartilage in vitro of cortical bone matrix gelatin was much higher than that of cancellous bone matrix gelatin. 展开更多
关键词 T 2toxin selenium (se) bone matrix gelatin (BMG) CHONDROCYTES CD44
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Cloning of catalase and expression patterns of catalase and selenium-dependent glutathione peroxidase from Exopalaemon carinicauda in response to low salinity stress 被引量:6
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作者 REN Hai LI Jian +4 位作者 LI Jitao YING Yu GE Hongxing LI Dongli YU Tianji 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期52-61,共10页
Catalase (CAT) and selenium-dependent glutathione peroxidase (Se-GPx) play a vital role in protecting organisms against various oxidative stresses by eliminating H202, The objective of this paper is to evaluate th... Catalase (CAT) and selenium-dependent glutathione peroxidase (Se-GPx) play a vital role in protecting organisms against various oxidative stresses by eliminating H202, The objective of this paper is to evaluate the roles of these antioxidant molecules in the ridgetail white prawn Exopalaemon carinicauda in response to low salinity stress. A complementary DNA (cDNA) containing the complete coding sequence of CAT was cloned from the hepatopancreas using reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends. The full-length cDNA of CAT (2 649 bp) contains a 5'-untranslated region (UTR) of 78 bp, a 3'- UTR of 1 017 bp, with a poly (A) tail, and an open reading frame of 1 554 bp encoding a 517-amino-acid polypeptide with predicted molecular mass of 58.46 kDa and estimated isoelectric point of 6.64. This CAT sequence contained the proximal active site signature (60FDRERIPERWHAKGAG76), proximal heme-ligand signature sequence (350RLFSYPDTH358) and three catalytic amino acid residues (His71, Asn144 and Tyr354). Sequence comparison showed that the CAT deduced amino acid sequence of E. carinicauda shared 68%-92% of identities with those of other species. Quantitative real-time PCR analysis revealed that CAT mRNA was widely expressed in the hepatopancreas (highest), hemocyte, eyestalk, heart, gill, muscle, ovary and stomach. Under low salinity stress, CAT and GPx mRNA expression levels both in the gill and hepatopancreas increased significantly at the first 48 h and 6 h respectively, indicating a tissue- and time-dependent antioxidant response in E. carinicauda. All these results indicate that E. carinicauda CAT is a member of the CAT family and might be involved in the acute response against low salinity stress. 展开更多
关键词 Exopalaemon carinicauda catalase (CAT) selenium-dependent glutathione peroxidase se-GPx) CLONING expression
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Effects of Vitamin E and Selenium on Free Radicals Metabolism of Broilers
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作者 徐建雄 王晶 +1 位作者 陆鸣 乔中东 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第S1期120-124,131,共6页
To study effects of vitamin E (VE) and selenium (Se) on dynamic variation rules, functions and metabolisms of different free radicals, 2 weeks age chicks were reared using four kinds of dietaries that differed in ... To study effects of vitamin E (VE) and selenium (Se) on dynamic variation rules, functions and metabolisms of different free radicals, 2 weeks age chicks were reared using four kinds of dietaries that differed in their VE and Se content. Free radicals in blood and tissues of broiler chicks were detected directly or indirectly using electron spin resonance (ESR) testing and biology chemistry methods. Results showed that NO free radical contents were decreasing due to the increasing of VE supplement in dietary and VE level was negatively correlated with NO free radicals. High Se supplement dietaries had the trend to induce the produce of NO free radicals. High VE and Se level dietaries significantly enhanced activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in serum and liver. Depending on time, SOD and GSH-Px activities were declining and increasing respectively, which indicated that being short of VE and/or Se in dietaries could link to the produce of O-2, H2O2 free radicals. With the deficiency lasting, organism would continuously produce large amounts of O-2 free radicals but H2O2 free radicals were just produced explosively at the beginning of deficiency and than tended to be steady. Low VE and/or Se levels in dietaries could remarkably enhance malondialdehyde(MDA)contents in tissues and the effect of low Se was stronger. VE and Se in dietary had synergic effect on metabolisms of NO, O-2 and H2O2 free radicals. 展开更多
关键词 VITAMIN E(VE) selenium(se) free RADICAL METABOLISM BROILER
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THE EFFECT ON PROTEOGLYCAN METABOLISM OF DEOXYNIVALENOL AND SELENIUM IN THE CULTURED HUMAN FETAL CHONDROCYTES IN VITRO
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作者 岳燕 曹峻岭 +5 位作者 李思远 谢龙 孙健 张增铁 张富军 师钟丽 《Journal of Pharmaceutical Analysis》 SCIE CAS 2005年第2期57-60,共4页
Objective To investigate the effect of deoxynivalenol (DON) and selenium (Se) on the morphology of chondrocytes and the metabolism of cartilage matrix, and the expression of aggrecanase-1, 2 mRNA in monolayer cultured... Objective To investigate the effect of deoxynivalenol (DON) and selenium (Se) on the morphology of chondrocytes and the metabolism of cartilage matrix, and the expression of aggrecanase-1, 2 mRNA in monolayer cultured chondrocytes in vitro. Methods To plant human fetal chondrocytes on the BMG, the expression of Aggrecanase-1, 2 mRNA were analyzed by RT-PCR, the immunohistochemistry of NITEGE epitope was quantitativly analyzed by the image collection and analysis system. Results With the increase of the concentration of DON, the damage of cultured chondrocytes was more and more severe; the expression of NITEGE epitope showed an increasing trend and the fluorescent bands of aggrecanase-1, 2 mRNA were more and more obvious. After adding Se, the damage was relieved, and there was a decreasing trend of NITEGE epitope expressed in matrix. Conclusion DON can enhance transcription of aggrecanase gene and increase the expression of NITEGE epitope which eventually lead to the metabolic disorder of cartilage proteoglycan. It suggested that Se can partially alleviate the damage of DON on cartilage, but can not completely prevent the occurrence of these changes. 展开更多
关键词 kashin-beck disease (KBD) bone matrix gelatin (BMG) deoxynivalenol (DON) selenium(se) NITEGE epitope AGGRECANAse
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Selenium speciation determines the angiogenesis effect through regulating selenoproteins to trigger ROS-mediated cell apoptosis and cell cycle arrest
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作者 Bin Feng Yan Zhang +3 位作者 Ting Liu Leung Chan Tianfeng Chen Jianfu Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第11期184-190,共7页
Tumor angiogenesis is closely related to tumor development,immune escape,and drug resistance.Therefore,the development of effective anti-tumor angiogenesis drugs is of great research significance.Although the current ... Tumor angiogenesis is closely related to tumor development,immune escape,and drug resistance.Therefore,the development of effective anti-tumor angiogenesis drugs is of great research significance.Although the current clinical angiogenesis inhibitors have achieved certain efficacy,they also pose the problems of limited and short duration of efficacy,drug resistance,and intrinsic toxicity.Anti-tumor angiogenesis strategies targeting endothelial cells(ECs)have attracted widespread attention in the development of highly effective and low toxicity anti-angiogenesis inhibitors.Studies have verified that the trace element selenium(Se)can inhibit tumor growth by inhibiting tumor angiogenesis through different mechanisms.Nevertheless,it is unclear whether Se speciation has different effects on anti-tumor angiogenesis.Herein,we found that Se exhibited effective anti-angiogenic activity,and its mechanisms of activity were determined by its chemical speciation.Organic Se can significantly inhibit tumor angiogenesis by targeting thioredoxin reductase(TrxR)to trigger cell apoptosis and cell cycle arrest and by increasing reactive oxygen species(ROS)production in ECs.Inorganic Se can induce cell cycle arrest and increase ROS production in ECs,showing promising anti-angiogenic effects.Se nanoparticles(SeNPs)slightly inhibit tumor angiogenesis by inducing apoptosis and cell cycle arrest and by increasing the production of ROS.In summary,this study elucidates the anti-angiogenic activity of Se speciation control with a view to providing a scientific reference for the design and development of novel Se-based highly effective and low toxicity angiogenesis inhibitors. 展开更多
关键词 se speciation ANGIOGENESIS Apoptosis Reactive oxygen species TXNRD selenium
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Investigation on the origin of Se-rich soils in Yutangba: Evidence from selenium speciation and native selenium
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作者 Jianming ZHU Haibo QIN +1 位作者 Lei LEI Wenliang HAN 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期46-47,共2页
关键词 土壤环境 土壤成分 土壤化学
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Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting
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作者 Zhao-ting SHANG Tang-ming LI +4 位作者 Bing-qian HU Min LIU Wang-ting LU Fan YU Yun ZHENG 《Frontiers in Energy》 SCIE EI CSCD 2024年第3期378-389,共12页
The use of two-dimensional(2D)layered metal-organic frameworks(MOFs)as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium(Se)-containing electrocatalysts for overal... The use of two-dimensional(2D)layered metal-organic frameworks(MOFs)as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium(Se)-containing electrocatalysts for overall water splitting.Herein,two strategies are then utilized to introduce Se element into the Co–Fe MOF,one being the etching of as-prepared MOF by SeO_(2) solution,and the other,the replacing of SCN−with SeCN−as the construction unit.The electrochemical activity of the pristine 2D MOF and their calcinated derivatives for catalyzing the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is evaluated and further discussed.It is found that the effect of introducing Se on improving electrochemical catalytic activity is significant for the HER process.Specifically,the calcinated derivative in the replacing method exhibits an overpotential of 235 mV for HER and 270 mV for OER at a current density of 10 mA/cm2.For comparing the two methods of introducing Se element into MOF,similar electrocatalytic activity can be achieved on the their calcinated derivatives.The high electrochemical performance of 2D CoFe-MOF derivatives may be resulted from the unique 2D hierarchical porous structure and strong synergistic effect between different components in the material. 展开更多
关键词 2D MOF selenium(se)-containing materials hydrogen evolution reaction(HER) oxygen evolution reaction(OER)
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手性有机硒化合物的催化不对称合成研究进展
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作者 李晖 殷亮 《化学学报》 北大核心 2025年第10期1237-1251,共15页
手性有机硒化合物在合成化学、材料科学、医药和农药等领域具有广泛的应用,在不对称催化领域还可以用作手性配体或有机小分子催化剂.因此,手性有机硒化合物的不对称合成受到化学家们的重视.利用含硒试剂与相应底物的催化不对称C—Se偶... 手性有机硒化合物在合成化学、材料科学、医药和农药等领域具有广泛的应用,在不对称催化领域还可以用作手性配体或有机小分子催化剂.因此,手性有机硒化合物的不对称合成受到化学家们的重视.利用含硒试剂与相应底物的催化不对称C—Se偶联反应是合成有机硒化合物最直接且最有效的策略之一.此综述着重介绍了利用该策略构建手性有机硒化合物的研究进展.根据不同的硒源类型,将反应分为亲电有机硒试剂与亲核底物的不对称偶联反应和亲核有机硒试剂与亲电底物的不对称偶联反应两类.另外,对一些代表性反应的机理和底物适用范围做了简要介绍. 展开更多
关键词 手性有机硒化合物 不对称催化 亲电硒试剂 亲核硒试剂 C—se键构建
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长三角典型地区土壤环境中Se的空间变异特征及其与人类健康的关系 被引量:16
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作者 孙维侠 赵永存 +3 位作者 黄标 廖菁菁 王志刚 王洪杰 《长江流域资源与环境》 CAS CSSCI CSCD 北大核心 2008年第1期113-118,共6页
农业土壤环境中硒(Se)的缺乏或过量都会通过食物链最终影响人类健康。在203个土壤采样点的基础上,利用GIS和地统计学相结合的方法,对江苏省如皋市农田土壤环境中Se的空间变异特征及其影响因素进行分析,同时,对土壤中Se的空间分布与长寿... 农业土壤环境中硒(Se)的缺乏或过量都会通过食物链最终影响人类健康。在203个土壤采样点的基础上,利用GIS和地统计学相结合的方法,对江苏省如皋市农田土壤环境中Se的空间变异特征及其影响因素进行分析,同时,对土壤中Se的空间分布与长寿人口的空间分布进行空间叠加分析。研究结果表明,如皋市土壤环境中总Se及水溶态Se的平均含量分别为0.13 mg/kg和2.16μg/kg,研究区处在相对低Se的土壤环境中。总Se的空间变异性不大,其空间分布比较均一;但水溶态Se的空间变异性较大,主要受成土条件及土壤母质、土壤类型及地形地貌等结构性因子的影响。水溶态Se对土壤的理化性质也比较敏感,特别是速效磷、有机质及全钾含量与水溶态硒的相关性较显著,因此在有机质及土壤养分含量较高、土壤颗粒组成较细的东部及北部地区水溶态硒的含量也较高。土壤水溶态Se的空间分异与长寿人口比率的空间分异呈极显著的正相关关系(P<0.01),相关系数达r =0.325,表明人类的健康长寿现象与环境中水溶态硒的含量有很大关系,但人类长寿的本质和真正机理仍需进一步研究验证。 展开更多
关键词 土壤环境 空间变异 人类健康
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Se肥施用方式和施用时期对水稻含Se量及产量的影响 被引量:17
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作者 迟凤琴 匡恩俊 +2 位作者 张久明 宿庆瑞 魏丹 《农业资源与环境学报》 CAS 2014年第6期560-564,共5页
在田间小区的试验条件下研究不同硒(Se)肥的施用方法及施用时期对水稻植株和籽粒中Se的吸收与富集的影响。研究表明:水稻在生长前期和旺盛时期对Se的吸收和积累有很大差异。与对照相比,苗床施Se、土壤施Se和叶面喷Se 3种方式均能明... 在田间小区的试验条件下研究不同硒(Se)肥的施用方法及施用时期对水稻植株和籽粒中Se的吸收与富集的影响。研究表明:水稻在生长前期和旺盛时期对Se的吸收和积累有很大差异。与对照相比,苗床施Se、土壤施Se和叶面喷Se 3种方式均能明显提高各生育期水稻植株和籽粒中Se的含量,富Se效果达到差异极显著水平。从稻米富Se效果看,富Se含量在0.163-0.207 mg·kg^-1之间,Se含量增加了5.8-7.6倍,且都在安全范围内。从水稻富Se的方式上,不同施Se方式富Se效果依次为水稻扬花期喷Se〉土壤施Se〉育苗期喷Se〉对照。从叶面喷施Se的时间上,稻米富Se效果依次是扬花期喷Se〉育苗期喷Se〉灌浆期喷Se〉齐穗期喷Se〉对照。从水稻富Se类型上看,外源无机Se和有机Se都能明显促进水稻对Se的积累。水稻育苗期和扬花期叶面喷Se在提高水稻稻米中含Se量的同时,并没有降低水稻产量。因此水稻叶面喷Se是一条安全、简单、易操作的途径。 展开更多
关键词 se 水稻 生育时期 产量
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不同pH条件和P-Se交互作用对茶园土壤Se(Ⅳ)吸附行为的影响 被引量:17
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作者 严佳 宗良纲 +3 位作者 杨旎 姚欢 马爱军 何任红 《农业环境科学学报》 CAS CSCD 北大核心 2014年第5期935-942,共8页
为了给生产上采取增施磷肥措施提高茶园土壤硒的有效性提供理论依据,通过实验室模拟实验,研究了不同pH条件和P-Se交互作用对茶园土壤Se(Ⅳ)吸附行为的影响。结果表明,在吸附液3种pH条件下Se(Ⅳ)的吸附平衡时间无明显变化。当吸附液pH=3... 为了给生产上采取增施磷肥措施提高茶园土壤硒的有效性提供理论依据,通过实验室模拟实验,研究了不同pH条件和P-Se交互作用对茶园土壤Se(Ⅳ)吸附行为的影响。结果表明,在吸附液3种pH条件下Se(Ⅳ)的吸附平衡时间无明显变化。当吸附液pH=3时土壤对Se(Ⅳ)的吸附量显著高于pH=5和pH=7的处理,而后两者之间差异较小。P-Se交互作用不仅延长了Se(Ⅳ)达到吸附平衡所需的时间,而且导致其平衡吸附量显著下降。茶园土壤对Se(Ⅳ)的吸附动力学曲线用双常数方程和Elovich方程拟合效果较好,而Langmuir方程、Freundlich方程和Temkin方程均可较好地描述Se(Ⅳ)的吸附热力学特征。P对土壤中Se(Ⅳ)吸附行为的影响与两者的摩尔浓度比以及添加顺序有关,在3种不同添加顺序下,Se(Ⅳ)吸附量的大小为先加Se后加P>Se与P同时加入>先加P后加Se,且当P/Se摩尔浓度比>1时,土壤对Se(Ⅳ)的吸附量呈现明显的下降趋势。 展开更多
关键词 茶园土壤 se(Ⅳ) PH P-se交互作用 吸附行为
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氢化物发生-原子荧光法测定不同产地绞股蓝及其根际土壤中As,Hg,Se 被引量:11
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作者 王晶 肖娅萍 +2 位作者 梁晓庆 邵显会 张珂 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2012年第3期813-816,共4页
通过优化了的氢化物发生—原子荧光法测定了7个省产绞股蓝及其根际土壤中As,Hg,Se三种元素的含量,研究结果表明:7个省产绞股蓝中As,Hg,Se的含量存在较大差异,但As和Hg两种重金属元素含量均低于《药用植物及制剂进出口绿色行业标准》中As... 通过优化了的氢化物发生—原子荧光法测定了7个省产绞股蓝及其根际土壤中As,Hg,Se三种元素的含量,研究结果表明:7个省产绞股蓝中As,Hg,Se的含量存在较大差异,但As和Hg两种重金属元素含量均低于《药用植物及制剂进出口绿色行业标准》中As和Hg的限量标准。Se元素含量同根际土壤中Se元素含量显示极显著相关性,故湖北恩施富硒区产绞股蓝中Se含量明显高于其他6省产绞股蓝。研究结果可以初步判定,绞股蓝中Se元素主要来源于土壤,而As和Hg元素的积累则不同于Se元素,还可能受到大气气溶胶的干、湿沉降等因素的影响。 展开更多
关键词 绞股蓝 根际土壤 湿法消解 氢化物发生-原子荧光法
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富硒灵芝硒蛋白(Se-GL-P)生化性质的初步分析 被引量:4
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作者 杜明 胡小松 +1 位作者 王聪 赵广华 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2007年第3期299-305,共7页
作为阐明一种从富硒灵芝中得到的蛋白(Se-GL-P)结构与功能关系的基础性工作,Se-GL-P的结构在此得到了初步表征.分子质量通过电泳和分子筛两种方法进行了测定,通过高效液相色谱、毛细管等电聚焦电泳、原位胶内酶切和Edman降解等方法分别... 作为阐明一种从富硒灵芝中得到的蛋白(Se-GL-P)结构与功能关系的基础性工作,Se-GL-P的结构在此得到了初步表征.分子质量通过电泳和分子筛两种方法进行了测定,通过高效液相色谱、毛细管等电聚焦电泳、原位胶内酶切和Edman降解等方法分别测定了蛋白质的氨基酸组成、等电点、肽图以及N端氨基酸序列等方面的性质,并对其同源性进行了鉴定.结果表明,该蛋白质的相对分子质量为36600,等电点为4.01,N端20个氨基酸序列为DINGGGATLPQKLYLTPDVL.实验得到结论:Se-GL-P是一种新的硒蛋白,并属于功能性DING蛋白家族的一员. 展开更多
关键词 富硒灵芝 硒蛋白 se-GL-P 性质 分析
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西藏大骨节病患者血清Se与几种细胞因子含量的变化 被引量:11
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作者 康龙丽 赵锋仓 +2 位作者 杨凤英 张银刚 郭雄 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2007年第6期531-532,共2页
目的:测定大骨节病患者和正常对照血清中硒和肿瘤坏死因子-α(TNF-α)、血管内皮生长因子(VEGF)和白介素-1(IL-1β)的水平。从细胞因子角度为研究其发病机制提供实验依据。方法:在西藏拉萨尼木县和墨竹工卡县的大骨节病区随机选取大骨... 目的:测定大骨节病患者和正常对照血清中硒和肿瘤坏死因子-α(TNF-α)、血管内皮生长因子(VEGF)和白介素-1(IL-1β)的水平。从细胞因子角度为研究其发病机制提供实验依据。方法:在西藏拉萨尼木县和墨竹工卡县的大骨节病区随机选取大骨节病患者30例(患者组),病区正常人30例(病区内对照组),在拉萨非大骨节病区选健康志愿者30例(病区外对照组),3组人群年龄和性别没有显著性差异。采取静脉血离心制备血清。采用荧光法测定血清Se,酶联免疫吸附测定法(ELISA)检测血清中细胞因子水平。结果:西藏大骨节病病区患者和正常人血清中Se低于非大骨节病区正常人;患者血清中TNF-α、VEGF和IL-1β的水平高于正常。血清Se与TNF-α、IL-1β水平呈负相关趋势。结论:低硒和血清中细胞因子水平升高在KBD的发病过程中起着某种作用。 展开更多
关键词 大骨节病 西藏 细胞因子(IL-1β VEGF TNF-α) 血清
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MSeC对鸡胚肝脏和脑组织中谷胱甘肽过氧化物酶和脱碘酶活性的影响 被引量:3
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作者 孟列素 谭武红 +4 位作者 苏敏 田东萍 杨占田 翟连榜 王立新 《中国地方病学杂志》 CAS CSCD 北大核心 2005年第4期382-385,共4页
目的通过补硒对正常鸡胚脑和肝脏中谷胱甘肽过氧化物酶(GPx)和脱碘酶活性的影响,探讨补硒对于正常动物的影响。方法对孵育8d的鸡胚注射不同剂量的甲基硒代半胱氨酸(MSeC),含硒量分别为0、1、5、10、20μg,第20天时测定脑组织和肝脏中硒... 目的通过补硒对正常鸡胚脑和肝脏中谷胱甘肽过氧化物酶(GPx)和脱碘酶活性的影响,探讨补硒对于正常动物的影响。方法对孵育8d的鸡胚注射不同剂量的甲基硒代半胱氨酸(MSeC),含硒量分别为0、1、5、10、20μg,第20天时测定脑组织和肝脏中硒水平、GPx活性及脱碘酶活性。结果对正常鸡胚补硒,可有效提高脑和肝脏的硒水平及GPx活性,还可提高肝脏Ⅰ型脱碘酶(IDⅠ)活性,但对脑中Ⅱ型脱碘酶(IDⅡ)活性没有影响。补硒量与除脑IDⅡ活性外的其他指标都显著相关(P<0.01)。结论MSeC是一个有效的补硒制剂,对于正常鸡胚,补硒可提高肝脏、脑组织硒水平和肝GPx、IDⅠ活性及脑GPx活性,其补硒效应有随补硒量增加而增强的趋势。 展开更多
关键词 甲基硒代米胱氨酸 脱碘酶 谷胱目肽过氧化酶 鸡胚
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