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青霉烷酸对甲氧基苄酯-1α-亚砜的合成方法改进
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作者 宋丹青 高丽梅 张致平 《中国药物化学杂志》 CAS CSCD 2001年第1期47-48,共2页
以 6 APA为起始原料 ,经溴化得 6 ,6 二溴青霉烷酸 ,用 11%~ 13 %的过氧乙酸氧化 ,所得的氧化产物 3以固体形式直接从溶液中析出 ,3以对甲氧基溴苄进行羧基保护 ,经还原合成了 β 内酰胺酶抑制剂他唑巴坦的关键中间体青霉烷酸对甲氧... 以 6 APA为起始原料 ,经溴化得 6 ,6 二溴青霉烷酸 ,用 11%~ 13 %的过氧乙酸氧化 ,所得的氧化产物 3以固体形式直接从溶液中析出 ,3以对甲氧基溴苄进行羧基保护 ,经还原合成了 β 内酰胺酶抑制剂他唑巴坦的关键中间体青霉烷酸对甲氧基苄酯 1α 亚砜 1。本方法操作简便 ,价格低廉 ,实施安全 。 展开更多
关键词 青霉烷对甲氧基苄酯-1α-亚砜 他唑巴坦 过氧化酸 氧化
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低浓度过氧乙酸空气消毒效果评价
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作者 虞晓颖 《浙江预防医学》 1996年第4期40-40,共1页
过氧乙酸是一种高效广谱消毒剂,对病毒、细菌、真菌及芽胞均能迅速杀灭.我院自80年代就开始应用过氧乙酸熏蒸进行空气消毒,对防止手术交叉感染,在无菌管理上起到了重要作用.但过氧乙酸对人体及金属制品有强烈的刺激、腐蚀作用,浓度越高... 过氧乙酸是一种高效广谱消毒剂,对病毒、细菌、真菌及芽胞均能迅速杀灭.我院自80年代就开始应用过氧乙酸熏蒸进行空气消毒,对防止手术交叉感染,在无菌管理上起到了重要作用.但过氧乙酸对人体及金属制品有强烈的刺激、腐蚀作用,浓度越高,刺激性越大.为寻求该药消毒的最佳浓度及剂量,我们试用低浓度过氧乙酸熏蒸法进行空气消毒,经检测效果良好,现介绍如下. 展开更多
关键词 消毒剂 过氧化酸 空气消毒 消毒效果
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银杏叶黄酮对小鼠和大鼠肝脏脂质过氧化的影响
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作者 唐祖年 韦玉先 +1 位作者 梁荣感 马孟斌 《华夏医学》 CAS 1995年第3期243-245,共3页
本文采用硫代巴比妥酸反应法,观察了银杏叶黄酮对小鼠和大鼠正常肝匀浆及四氯化碳(ccl4)引起的脂质过氧化作用的影响,并观察了对小鼠血清SGPT的影响。结果表明,银杏叶黄酮对体外小鼠和大鼠肝匀浆及ccl4引起的脂质过氧... 本文采用硫代巴比妥酸反应法,观察了银杏叶黄酮对小鼠和大鼠正常肝匀浆及四氯化碳(ccl4)引起的脂质过氧化作用的影响,并观察了对小鼠血清SGPT的影响。结果表明,银杏叶黄酮对体外小鼠和大鼠肝匀浆及ccl4引起的脂质过氧化均有显著降低。而对体内小鼠的脂质过氧化及ccl4诱导的SGPT升高无明显影响。 展开更多
关键词 银杏叶黄酮 脂质过氧化 硫代巴比妥反应 肝匀浆.
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Effects of Catalase and Ascorbate Peroxidase on the Root Growth of Rice under Cadmium Stress 被引量:9
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作者 宋新华 王凯 +1 位作者 郭蕾蕾 赵凤云 《Agricultural Science & Technology》 CAS 2011年第9期1256-1259,共4页
[Objective] The research aimed to study the correlations between catalase(CAT) and ascorbate peroxidase(ASP) and the growth and development of rice roots under cadmium stress.[Method] Taking rice variety Zhonghua ... [Objective] The research aimed to study the correlations between catalase(CAT) and ascorbate peroxidase(ASP) and the growth and development of rice roots under cadmium stress.[Method] Taking rice variety Zhonghua No.11 as materials,the changes of rice seedlings under the treatment conditions of Cd,Cd+CAT inhibitor,Cd+APX inhibitor were studied.[Result] Under Cd stress,inhibition of CAT activity caused the significant inhibition on the growth of aerial parts,decreased the number of adventitious roots and lateral roots,but it can significant promote the elongation growth of adventitious roots and lateral roots.Moreover,the length of the first lateral root from root tip on the primary roots and adventitious roots was also increased than control.When APX activity was inhibited,the growth changes of rice were similar with that treated by CAT inhibitor.[Conclusion] CAT and APX may play important roles in the regulation of rice root system growth in both non-stress and Cd-stressed rice 展开更多
关键词 Cd stress CATALASE Ascorbate peroxidase
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Oxidative leaching behavior of metalliferous black shale in acidic solution using persulfate as oxidant 被引量:5
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作者 刘志雄 向延鸿 +4 位作者 尹周澜 吴贤文 蒋剑波 陈义光 熊利芝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第2期565-574,共10页
The oxidative dissolution of metalliferous black shale in sulfuric acid solution using sodium persulfate as an oxidant was investigated. The effects of leaching factors including leaching temperature, leaching time, s... The oxidative dissolution of metalliferous black shale in sulfuric acid solution using sodium persulfate as an oxidant was investigated. The effects of leaching factors including leaching temperature, leaching time, stirring speed, initial concentration of sodium persulfate and sulfuric acid and particle size on the leaching rate were studied as well. The leaching kinetics of molybdenum, nickel and iron from metalliferous black shale shows that the leaching rate is controlled by a chemical reaction through a layer on the unreacted shrinking core. The leaching process follows the kinetics model 1-(1-a)^1/3=kt with apparent activation energies of 34.50, 43.14 and 71.79 kJ/mol for Mo, Ni and Fe, respectively. The reaction orders in sodium persulfate are 0.80, 1.01 and 0.75 for molybdenum, nickel and iron, respectively, while in sulfuric acid, these orders are 0.45, 0.75 and 0.50 for molybdenum, nickel and iron, respectively. In addition, the reaction mechanism for the dissolution of the metalliferous black shale was discussed. 展开更多
关键词 metalliferous black shale oxidative leaching KINETICS sodium persulfate
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Regulation of Heat Shock Factor AtHsfA1a on Ascorbate Peroxidase under Heat Stress in Arabidopsis thaliana 被引量:1
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作者 郭丽红 谭越 杨晓虹 《Agricultural Science & Technology》 CAS 2016年第8期1786-1789,共4页
[Objective] This study was conducted to investigate the regulation of heat shock factor AtHsfA1a on ascorbate peroxidase under heat stress in Arabidopsis thaliana. [Method] After heat stress treatment on transgenetic ... [Objective] This study was conducted to investigate the regulation of heat shock factor AtHsfA1a on ascorbate peroxidase under heat stress in Arabidopsis thaliana. [Method] After heat stress treatment on transgenetic A. thaliana with silenced endogenetic AtHsfA1a gene and wild A. thaliana plants as materials, the change in activity of APX enzyme was analyzed by spectrophotometry, the expression level of APX gene was investigated by real-time fluorescent quantitative PCR, and the binding condition of AtHsfAla with the promoter region of APX gene was analyzed by chromatin immunoprecipitation assay. [Result] The activity and mRNA level of APX in plants with silenced endogenetic AtHsfAla gene were higher than those in wild plants. Fragments of the promoter region of APX gene were not screened from the plants with silenced endogenetic AtHsfA1a gene, but found in wild plants. [Conclusion] This study provides a theoretical basis for the understanding of the important role of AtHsfAla in resistance to stress in plant, and is of great significance to the revealing of mechanism of resistance to stress in plant. 展开更多
关键词 Arabidopsis thaliana Heat shock factor AtHsfAla Aascorbate peroxidase Heat stress
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Heterogeneous catalytic activation of peroxymonosulfate for efficient degradation of organic pollutants by magnetic Cu^0/Fe_3O_4 submicron composites 被引量:10
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作者 聂刚 黄佳 +3 位作者 胡冶州 丁耀彬 韩小彦 唐和清 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期227-239,共13页
Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-pr... Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-prepared magnetic Cu^0/Fe3O4 submicron composites were composed of Cu^0 and Fe3O4 crystals and had an average size of approximately 220 nm.The Cu^0/Fe3O4 composites could efficiently catalyze the activation of PMS to generate singlet oxygen,and thus induced the rapid degradation of rhodamine B,methylene blue,orange Ⅱ,phenol and 4-chlorophenol.The use of0.1 g/L of the Cu^0/Fe3O4 composites induced the complete removal of rhodamine B(20 μmol/L) in15 min,methylene blue(20 μmol/L) in 5 min,orange Ⅱ(20 μmol/L) in 10 min,phenol(0.1mmol/L) in 30 min and 4-chlorophenol(0.1 mmol/L) in 15 min with an initial pH value of 7.0 and a PMS concentration of 0.5 mmol/L.The total organic carbon(TOC) removal higher than 85%for all of these five pollutants was obtained in 30 min when the PMS concentration was 2.5 mmol/L.The rate of degradation was considerably higher than that obtained with Cu^0 or Fe3O4 particles alone.The enhanced catalytic activity of the Cu^0/Fe3O4 composites in the activation of PMS was attributed to the synergistic effect of the Cu^0 and Fe3O4 crystals in the composites.Singlet oxygen was identified as the primary reactive oxygen species responsible for pollutant degradation by electron spin resonance and radical quenching experiments.A possible mechanism for the activation of PMS by Cu^0/Fe3O4 composites is proposed as electron transfer from the organic pollutants to PMS induces the activation of PMS to generate ^1O2,which induces the degradation of the organic pollutants.As a magnetic catalyst,the Cu^0/Fe3O4 composites were easily recovered by magnetic separation,and exhibited excellent stability over five successive degradation cycles.The present study provides a facile and green heterogeneous catalysis method for the oxidative removal of organic pollutants. 展开更多
关键词 Heterogeneous catalysis Magnetic Cu^0/Fe3O4 composite PEROXYMONOSULFATE Singlet oxygen Oxidative degradation
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Preliminary Studies on High-performance Liquid Chro-matography Chemiluminescence Determination of theSaturated Fatty Acids(C_(16) C_(18))in Human Serum 被引量:1
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作者 段更利 中岛宪一郎 +1 位作者 黑田直敬 秋山修三 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第1期22-29,共8页
The peroxyoxalate chemiluminescence(CL)detection of fatty acids in human se- rum combined with high-performance liquid chromatography (HPLC)is described.Some fatty acids in serum were extracted with a 1 :1(v/v)mixture... The peroxyoxalate chemiluminescence(CL)detection of fatty acids in human se- rum combined with high-performance liquid chromatography (HPLC)is described.Some fatty acids in serum were extracted with a 1 :1(v/v)mixture of chloroform-n-heptane.2-(4-Hydrazinocarbonyl- phenyl)-4,5-diphenylimidazole (HCPI) was used as a fluorescent labelling reagent of the fatty acids. The labelling reaction was carried out at 30℃ for 1 h at pH 6.5 and the resulting reaction mixture was sudjected to HPLC. The labelled fatty acid C_(17)(P-C_(17))was used as the internal standard. The la- belled fatty acids C_(16) and C_(18) were separated within 18 min on an ODS-8OTM column (150 mm× 6 mm ID,5μm,Tosoh Japan).The calibrlation curves of fatty acids from the spiked control serum were Y_1=-0.003 7 + 0.0028X_1,r=0.994 for FA C_( 16) and Y_2=0.00 1 2 + 0.00098X_2,r=0.999 for FA C_( 18),respectively.The average recoveries of facids from the spiked contrl serum were 107.2%(n=8,RSD=4.3%)for FA C_(16) and 97.35%(n=8, RSD=4.0%)for FA C_(18),respectively.The lower detection limits of fatty acids after reaction were 12μmol per 20μl injection for FA C_(16) and 18 μmol per 20μl injection for FA C_(18),respectively(signal to noise ratio, S/N=2).The HPLC/CL method was applied to the determination of FA C_(16) and FA C_(18) in normal human serum and the results showed that the concentrations of fatty acids in normal human serum were 0.134 ± 0.009 μ mol/ml serum(n=5) for FA C_(16) and 0.052±0.028 μmol/ml serum(n=5)for FA C_(18),respectively. 展开更多
关键词 Fatty acids High-performance Liquid Chromatography Peroxyoxalate chemi- luminescence detection Human serum
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Effect of Polyamine Priming on Chilling Tolerance of Lolium perenne during Seed Imbibition 被引量:4
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作者 王应芬 王普昶 +3 位作者 吴佳海 赵丽丽 莫本田 黎俊 《Agricultural Science & Technology》 CAS 2012年第9期1859-1863,1869,共6页
[Objective] This study aimed to investigate the effect of potyamine priming on physiological and biochemical variations of Lolium perenne embryos and seed germination. [Method] With annual Lolium perenne (Diamond T a... [Objective] This study aimed to investigate the effect of potyamine priming on physiological and biochemical variations of Lolium perenne embryos and seed germination. [Method] With annual Lolium perenne (Diamond T and Grazing-8000) as experimental materials, after priming with 0.5 mmol/L putrescine (Put), spermidine (Spd) and spermine (Spm) for 24 h and chilling imbibition at 5 ℃ for 12, 24, 36 and 48 h, the effect of Put, Spd and Spm priming on chilling tolerance and germination ability of annual Lolium perenne seeds during imbibition was investigated. [Result] Put, Spd and Spm priming improved the activities of peroxidase (POD), catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) and content of soluble protein content under low temperature stress, significantly in-creased the germination rate, and shortened the average germination duration. After chilling imbibition for 48 h, compared with the control, the average germination rate of annual Lolium perenne seeds was improved by 15.5% and 12.0% after Put, Spd and Spm priming, and the average germination duration was shortened by 1.21 and 1.14 d. During seed imbibition, the chilling tolerance of Grazing-8000 was stronger than that of Diamond T. Overall, Put, Spd and Spm treatment could increase the chilling tolerance of annual Lolium perenne seeds during imbibition, and improve the germination ability of seeds under low temperature stress. [Conclusion] Results of this study provided theoretical basis for the application of seed priming technology in the production of annual ryegrass. 展开更多
关键词 Polyamines Annual Lofium perenne Chilling tolerance Seed imbibition Antioxidant enzymes
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多环芳烃接触者生物膜损伤指标的调查研究 被引量:4
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作者 张太江 马永志 +3 位作者 肖文 张俊萍 王诗斌 张巧 《广西预防医学》 2003年第4期201-204,共4页
目的了解多环芳烃接触者体内生物膜损伤情况 ,为劳动保护提供科学依据。方法对多环芳烃接触者55名 (接触组 )、正常对照人群40名 (对照组 )血清中丙二醛 (MDA)、超氧化物歧化酶总量 (T-SOD)、血清唾液酶 (SA)进行测定。结果接触组血清MD... 目的了解多环芳烃接触者体内生物膜损伤情况 ,为劳动保护提供科学依据。方法对多环芳烃接触者55名 (接触组 )、正常对照人群40名 (对照组 )血清中丙二醛 (MDA)、超氧化物歧化酶总量 (T-SOD)、血清唾液酶 (SA)进行测定。结果接触组血清MDA、SA含量显著高于正常对照组 (P<0.001) ;血清T-SOD含量显著低于正常对照组 (P<0.001)。另外 ,对焦炉工按年龄、工龄和吸烟与否分别进行再分组分析 ,各指标差异均无显著性 (P>0.05)。结论多环芳烃职业接触者在临床症状出现前 。 展开更多
关键词 多环芳烃 职业接触者 生物膜损伤指标 血清丙二醛 血清唾液酶 氧化物歧化酶 PAHS 煤焦沥青 SOD MDA SA CTP LPO 细胞不饱和脂质过氧化
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Comparison of Biochemical Substances in the Fiber Development of Different Cotton Varieties
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作者 葛杰 罗淑萍 +2 位作者 马德英 羌松 姚正培 《Agricultural Science & Technology》 CAS 2015年第3期439-441,共3页
Zhongmian 42 and Xinluzao 36 were used as raw materials to determine the contents of soluble sugar and protein, as well as dynamic changes of enzyme activities after flowering during cotton fiber growth. The results s... Zhongmian 42 and Xinluzao 36 were used as raw materials to determine the contents of soluble sugar and protein, as well as dynamic changes of enzyme activities after flowering during cotton fiber growth. The results showed that contents of soluble protein in the two species sharply declined 7 to 21 days after flowering, as the soluble sugar in Zhongmian 42 leveling off after 21 days of flowering while the soluble sugar in Xinluzao 36 dropped notably after 21 days of flowering before remaining stable after seven days later. The soluble sugar decreased 7 to 14 days after flowering before sharply rising to the maximum seven days later, and then began to decline quickly. The soluble sugar was the minimum after 35 days of flowering and then remaining stable. Peroxidase activity generally increased. Indole-3- acetic acid oxidase activities were low at 7 days after flowering. IAAO activity reached to the peaks on the 14th and 28th day after flowering. IAAO activity of two varieties decreased with the same trend 35 days after flowering. 展开更多
关键词 Cotton (Gossypium hirsutum L.) Cotton fiber Soluble sugar Soluble protein PEROXIDASE Indole-3-acetic acid oxidase
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麝香草酚抗氧化和抑制酪氨酸酶活性研究 被引量:3
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作者 刘敏 余雄英 +2 位作者 舒青龙 唐芳瑞 左爱仁 《时珍国医国药》 CAS CSCD 北大核心 2018年第2期274-277,共4页
目的检测麝香草酚的抗氧化活性和抑制酪氨酸酶活性。方法采用清除DPPH、ABTS、羟自由基、超氧自由基,抑制脂质过氧化活性和抑制酪氨酸酶活性的方法,检测麝香草酚的抗氧化活性和抑制酪氨酸酶活性。结果麝香草酚具有明显的抗氧化活性和抑... 目的检测麝香草酚的抗氧化活性和抑制酪氨酸酶活性。方法采用清除DPPH、ABTS、羟自由基、超氧自由基,抑制脂质过氧化活性和抑制酪氨酸酶活性的方法,检测麝香草酚的抗氧化活性和抑制酪氨酸酶活性。结果麝香草酚具有明显的抗氧化活性和抑制酪氨酸酶活性,呈浓度依赖性效应。在清除DPPH、ABTS、羟自由基、超氧自由基,抑制脂质过氧化活性和抑制酪氨酸酶活性试验中,麝香草酚的体系终浓度IC_(50)分别为120,40.9,24,60,29.17μmol/L和37.49μmol/L。作为阳性对照药物的山柰酚的体系终浓度IC_(50)分别为80,9.09,12,12,8.33μmol/L和3.33μmol/L。麝香草酚具有1个酚羟基,山柰酚具有3个酚羟基,分子结构的不同,导致麝香草酚、山柰酚不同的抗氧化活性和抑制酪氨酸酶活性。结论研究表明麝香草酚具有明显的抗氧化活性和抑制酪氨酸酶活性,是值得进一步研究的抗氧化防衰老类候选药物、化妆品原料和食品添加剂。 展开更多
关键词 麝香草酚 羟自由基 超氧自由基 脂质过氧化和抑制酪氨
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Role of hydrazine and hydrogen peroxide in aluminium hydroxide precipitation from sodium aluminate solution 被引量:3
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作者 N.K.SAHU C.K.SARANGI +4 位作者 B.DASH B.C.TRIPATHY B.K.SATPATHY D.MEYRICK I.N.BHATTACHARYA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期615-621,共7页
Aluminium hydroxide precipitation from synthetic sodium aluminate solution was studied in the presence of hydrazine or hydrogen peroxide. The addition of low concentration of hydrazine is found to be effective, while ... Aluminium hydroxide precipitation from synthetic sodium aluminate solution was studied in the presence of hydrazine or hydrogen peroxide. The addition of low concentration of hydrazine is found to be effective, while higher amount of hydrogen peroxide is required to generate similar effect. XRD data confirm the product phase to be gibbsitic by nature. The scanning electron micrographs (SEM) show that agglomerated products form in the presence of hydrazine while fine discrete particles are produced with hydrogen peroxide. The probable mechanism of precipitation in the presence of hydrazine and hydrogen peroxide is also discussed. 展开更多
关键词 aluminium hydroxide HYDRAZINE hydrogen peroxide sodium aluminate PRECIPITATION
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Sphincter of Oddi hypomotility and its relationship with duodenal-biliary reflux,plasma motilin and serum gastrin 被引量:22
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作者 Zhen-Hai Zhang Shuo-Dong Wu +4 位作者 Bing Wang Yang Su Jun-Zhe Jin Jing Kong Hao-Lin Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第25期4077-4081,共5页
AIM: To detect whether patients with a T tube after cholecystectomy and choledochotomy have duodenal-biliary reflux by measuring the radioactivity of Tc99m-labeled diethylene triamine penta-acetic acid (DTPA) in the b... AIM: To detect whether patients with a T tube after cholecystectomy and choledochotomy have duodenal-biliary reflux by measuring the radioactivity of Tc99m-labeled diethylene triamine penta-acetic acid (DTPA) in the bile and whether the patients with duodenal-biliary reflux have sphincter of Oddi hypomotility, by mea-suring the level of plasma and serum gastrin of the patients. Finally to if there is close relationship among sphincter of Oddi hypomotility, duodenal-biliary reflux and gastrointestinal peptides. METHODS: Forty-five patients with a T tube after cholecystectomy and choledochotomy were divided into reflux group and control group. The level of plasma and serum gastrin of the patients and of 12 healthy volunteers were measured by radioimmunoas-say. Thirty-four were selected randomly to undergo choledochoscope manometry. Sphincter of Oddi basal pressure (SOBP), amplitude (SOCA), frequency of con-tractions (SOF), duration of contractions (SOD), duo-denal pressure (DP) and common bile duct pressure (CBDP) were scored and analyzed. RESULTS: Sixteen (35.6%) patients were detected to have duodenal-biliary reflux. SOBP, SOCA and CBDP in the reflux group were much lower than the controlgroup (t = 5.254, 3.438 and 3.527, P < 0.001). SOD of the reflux group was shorter than the control group (t = 2.049, P < 0.05). The level of serum gastrin and plasma motilin of the reflux group was much lower than the control group (t = -2.230 and -2.235, P < 0.05). There was positive correlation between the level of plasma motilin and SOBP and between the level of serum gastrin and SOBP and CBDP. CONCLUSION: About 35.9% of the patients with a T tube after cholecystectomy and choledochotomy have duodenal-biliary reflux. Most of them have sphincter of Oddi hypomotility and the decreased level of plasma motilin and serum gastrin. The disorder of gastroin-testinal hormone secretion may result in sphincter of Oddi dysfunction. There is a close relationship between sphincter of Oddi hypomotility and duodenal-biliary re-flux. 展开更多
关键词 Sphincter of Oddi Tc99m-labeled diethylenetriamine penta-acetic acid PRESSURE MOTILIN GASTRIN
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Bicarbonate activation of hydrogen peroxide: A new emerging technology for wastewater treatment 被引量:7
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作者 Ali Jawad 陈朱琦 尹国川 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期810-825,共16页
The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one o... The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one of the most efficient treatment systems, is able to degrade various organics with the help of powerful ·OH radicals. This review focuses on recent progress in the use of bicarbonate activated hydrogen peroxide for wastewater treatment. The introduction of bicarbonate to pollutant treatment has led to appreciable improvements, not only in process efficiency, but also in process stability. This review describes in detail the applications of this process in homogeneous and heterogeneous systems. The enhanced degradation, limited or lack of leaching during heterogeneous degradation, and prolonged catalysts stability during degradation are salient features of this system. This review provides readers with new knowledge regarding bicarbonate, including the fact that it does not always harm pollutant degradation, and can significantly benefit degradation under some conditions. 展开更多
关键词 Wastewater treatment Bicarbonate activated hydrogen peroxide Catalyst leaching Pollutant degradation Catalytic oxidation
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Peracetic Acid Synthesis by Acetaldehyde Liquid Phase Oxidation in Trickle Bed Reactor 被引量:2
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作者 张腾云 罗京莉 +1 位作者 K.Chuang 钟理 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期320-325,共6页
In this paper,shorter residence time(a few minutes)with high yield in the trickle bed process for per- acetic acid synthesis by acetaldehyde liquid phase oxidation can be realized on the selected packing material SA... In this paper,shorter residence time(a few minutes)with high yield in the trickle bed process for per- acetic acid synthesis by acetaldehyde liquid phase oxidation can be realized on the selected packing material SA-5118.For acetaldehyde in acetone with ferric ion as catalyst,the optimized process conditions were presented. The main factors influencing the yield,selectivity and conversion are residence time,temperature and acetaldehyde concentration,respectively.The temperature range checked is from 30 to 65℃.High yield of 81.53%with high se- lectivity of 91.84%can be obtained at higher temperature of 55℃when the residence time is 5.5min and the acet- aldehyde concentration is 9.85%(by mass).And there is a critical acetaldehyde concentration point(Cccp)between 18%and 19.5%(by mass).At temperature less than 55℃,the highest yield to peracetic acid at each temperature level increases with temperature when the acetaldehyde concentration is below Cccp and decreases with temperature when the acetaldehyde concentration is above Cccp. 展开更多
关键词 peracetic acid liquid phase oxidation ACETALDEHYDE trickle bed
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Lead exposure increases oxidative stress in the gastric mucosa of HCl/ethanol-exposed rats 被引量:3
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作者 Samuel Babafemi Olaleye Oluwatosin Adekunle Adaramoye +1 位作者 Perebiri Peter Erigbali Olasupo Sunday Adeniyi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第38期5121-5126,共6页
AIM: To investigate the role of reactive oxygen species in the ulcer-aggravating effect of lead in albino rats. METHODS: Albino Wistar rats were randomly divided into three groups and treated orally with 100 mg/L (low... AIM: To investigate the role of reactive oxygen species in the ulcer-aggravating effect of lead in albino rats. METHODS: Albino Wistar rats were randomly divided into three groups and treated orally with 100 mg/L (low dose) or 5000 mg/L (high dose) of lead acetate for 15 wk. A third group received saline and served as control. At the end of wk 15, colorimetric assays were applied to determine the concentrations of total protein and nitrite, the activities of the oxidative enzymes catalase and superoxide dismutase, and lipid peroxidation in homogenized gastric mucosal samples. RESULTS: Exposure of rats to lead significantly increased the gastric mucosal damage caused by acidified ethanol. Although the basal gastric acid secretory rate was not significantly altered, the maximal response of the stomach to histamine was significantly higher in the lead-exposed animals than in the unexposed control group. Exposure to low and high levels of lead significantly increased gastric lipid peroxidation to 183.2% ± 12.7% and 226.1% ± 6.8% of control values respectively (P < 0.0). On the other hand, lead exposure significantly decreased catalase and superoxide dismutase (SOD) activities and the amount of nitrite in gastric mucosal samples. CONCLUSION: Lead increases the formation of gastric ulcers by interfering with the oxidative metabolism in the stomach. 展开更多
关键词 Lead ULCER Lipid peroxidation CATALASE Gastric acid
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Synergistic degradation of phenols by bimetallic CuO-Co_3O_4@γ-Al_2O_3 catalyst in H_2O_2/HCO_3^- system 被引量:7
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作者 李一冰 Ali Jawad +4 位作者 Aimal Khan 卢小艳 陈朱琦 刘卫东 尹国川 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期963-970,共8页
The development of new catalytic techniques for wastewater treatment has long attracted much attention from industrial and academic communities.However,because of catalyst leaching during degradation,catalysts can be ... The development of new catalytic techniques for wastewater treatment has long attracted much attention from industrial and academic communities.However,because of catalyst leaching during degradation,catalysts can be short lived,and therefore expensive,and unsuitable for use in wastewater treatment.In this work,we developed a bimetallic CuO-Co3O4@γ-Al2O3 catalyst for phenol degradation with bicarbonate-activated H2O2.The weakly basic environment provided by the bicarbonate buffer greatly suppresses leaching of active Cu and Co metal ions from the catalyst.X-ray diffraction and X-ray photoelectron spectroscopy results showed interactions between Cu and Co ions in the CuO-Co3O4@γ-Al2O3 catalyst,and these improve the catalytic activity in phenol degradation.Mechanistic studies using different radical scavengers showed that superoxide and hydroxyl radicals both played significant roles in phenol degradation,whereas singlet oxygen was less important. 展开更多
关键词 Synergistic effect Phenol degradation Copper/cobalt oxide catalyst Mechanistic study Bicarbonate-activated H2O2
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Soil Enzyme Activity Changes in Different-Aged Spruce Forests of the Eastern Qinghai-Tibetan Plateau 被引量:48
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作者 ZHANGYong-Mei ZHOUGuo-Yi +1 位作者 WUNing BAOWei-Kai 《Pedosphere》 SCIE CAS CSCD 2004年第3期305-312,共8页
Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 y... Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in theeastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems healthwere analyzed. Plots 10 X 10 m with 4 replications were established to investigate three hypotheses:soil enzyme activities a) would increase with the restoration process; b) would be greater insurface soils than at lower depths; and c) would be correlated to selected physicochemicalproperties. Results showed that as the forests developed after restoration, invertase and peroxidaseactivities usually increased up to the 23 year point. Also soil enzyme activities were associatedwith surface soils and decreased with depths, suggesting that in earlier restoration stages surfaceaddition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzymeactivities and some selected chemical properties. Therefore, temporal changes in enzyme activitiesshould be included as an indicator when evaluating sustainable forest management practices. 展开更多
关键词 acid phosphatase CATALASE INVERTASE PEROXIDASE spruce forest (picea spp.)
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Ursodeoxycholic acid and superoxide anion 被引量:2
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作者 Predrag Ljubuncic Omar Abu-Salach Arieh Bomzon 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第31期4875-4878,共4页
AIM: To investigate the ability of ursodeoxycholic acid (UDCA) to scavenge superoxide anion (O2-).METHODS: We assessed the ability of UDCA to scavenge (O2-) generated by xanthine-xanthine oxidase (X-XO) in a cell-free... AIM: To investigate the ability of ursodeoxycholic acid (UDCA) to scavenge superoxide anion (O2-).METHODS: We assessed the ability of UDCA to scavenge (O2-) generated by xanthine-xanthine oxidase (X-XO) in a cell-free system and its effect on the rate of O2--induced ascorbic acid (AA) oxidation in hepatic post-mitochondrial supernatants.RESULTS: UDCA at a concentration as high as 1 mmol/Ldid not impair the ability of the X-XO system to generate O2-, but could scavenge O2- at concentrations of 0.5 and 1 mmol/L, and decrease the rate of AA oxidation at a concentration of 100 μmol/L.CONCLUSION: UDCA can scavenge O2-, an action that may be beneficial to patients with primary biliary cirrhosis. 展开更多
关键词 Ursodeoxycholic acid Superoxide anion ANTIOXIDANT
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