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1.
TATP-铜(Ⅱ)-氨基酸配合物的合成及其SOD活性   总被引:1,自引:0,他引:1  
超氧化物歧化酶(SOD)是清除生物体内O2-的重要防卫,它能有效地催化O2-歧化成O2和H2O2,从而消除O2-对生物体的危害[1-4]。由于天然SOD在稳定性、膜穿透性、生物利用度和免疫原性等方面尚存在着一些限制应用的因素[5],因此模拟SOD活性部位结构且具有清除超氧阴离子自由基功能的小  相似文献   

2.
超氧化物歧化酶(SOD)广泛存在于人、动物、植物、藻类以及原核生物中,它能够催化超氧阴离子自由基发生歧化反应,平衡机体内的氧自由基,是一切生物体内重要的抗活性氧毒害的酶[1].  相似文献   

3.
在离体大鼠心脏灌流模型上,发现用高[Ca~(2+)](4.5mmol/L)、高[K~+](8.7mmol/L)或自由基发生系统灌流,显著增加心肌对脂质体的摄取。静脉注射与大鼠心肌细胞抗体共价结合的脂质体,显著增强了脂质体趋心肌组织的靶向性。用脂质体携载超氧化物歧化酶(superoxide dismutase,SOD)治疗大鼠心肌缺血-再灌注损伤,其疗效远优于单用SOD治疗。实验结果表明,脂质体作为药物载体治疗缺血性心脏病可能具有临床应用前景。  相似文献   

4.
超氧化物歧化酶(SOD)是一类重要的金属酶,能催化超氧阴离子自由基(O)发生歧化反应:2O2+2H^+↑SOD→H2O2+O2从而将其清除。根据金属辅基的不同,可将其分为铜、锌-SOD、锰-SOD、铁-SOD三类。文献[1,2]证明,SOD活力受微量元素铜、锌、铁的影响较大。本试验用半胱氨酸阻断法测定了不同浓度的硒(Ⅵ)、锰(Ⅱ)、氟(F^-)对SOD活力的影响。  相似文献   

5.
SOD(超氧化物歧化酶)广泛存在于自然界一切生物体内,是生物学前沿的研究课题之一,前人对其进行了深入的研究。本文将SOD和二茂铁用新鲜蛋清这种廉价、易得的膜固定剂代替BSA(牛血清白蛋白)修饰到电极上,研究它们在修饰电极上与过氧化氢的作用,并进一步证明SOD与二茂铁之间是否存在着协同效应。  相似文献   

6.
天然超氧化物歧化酶(SOD)可以专一地清除生物体内的超氧阴离子自由基O-2,从而可预防活性氧中毒、抗衰老、减少癌症等疾病的发生。但是SOD分子量大、不易透过细胞膜、在生物体内半衰期短并有异体抗原性、价格昂贵,临床使用受到很大限制。2 (2′,5′ 二氯 苯氨基) 苯乙酸(双氯芬酸)、2 (3′ 氯 苯氨基) 苯甲酸(氯灭酸)是二苯胺类衍生物,临床用作消炎镇痛药,有清除O-2的能力[1],而且活性稳定。本文制备的它们的Cu(Ⅱ)配合物,可作为SOD模拟物[2],且活性较高。1 实验部分1 1 主要试剂和仪器双氯芬酸钠(纯度99 5%河南汤阴永奈化工有限…  相似文献   

7.
铜-(N-正十二碳酰双甘肽)配合物模拟SOD研究   总被引:2,自引:0,他引:2  
合成一种新的SOD模拟物带功能基的长链铜()氨基酸配合物N-正十二碳酰双甘肽合铜[Cu(C12-Gly-Gly)]和二-(N-正十二碳酰双甘肽合铜)[Cu(C12-Gly-Gly)2].用脉冲辐解法测定了其SOD样活性,发现Cu(C12-Gly-Gly)2的SOD样活性基本接近于天然SOD,达到了整体模拟SOD的效果.  相似文献   

8.
微量热法研究超氧化物歧化酶反应   总被引:2,自引:0,他引:2  
用微量热法研究了以过氧化氢酶反应为氧产生体系、以邻苯三酚自氧化反应为底物产生体系的超氧化物歧化酶 (SOD)催化超氧阴离子歧化反应的热动力学 ,测得 2 98 1 5K和pH 8 0时SOD反应和邻苯三酚自氧化反应的摩尔反应焓分别为- 1 6 0 .1和 - 2 1 8kJ·mol-1,并建立了一种新的SOD活力测定方法———微量热测活法 .实验结果表明 ,SOD对邻苯三酚自氧化反应的动力学参数及反应机理没有影响 ,在无SOD存在和有SOD存在时该自氧化反应在限量氧气条件下均遵循二级反应动力学 (对邻苯三酚和氧气各为一级 ) ,2 98 1 5K和 pH 8 0时其二级速率常数分别为 1 2 5和 1 30L·mol-1·s-1,同时提出了SOD抑制邻苯三酚自氧化反应的可能机理 .  相似文献   

9.
IntroductionSuperoxide dismutases play an important rolein organisms′ defense against highly reactiveoxygen species by removing the superoxideanions[1— 3 ] . According to their metal cofactor,three differentclasses of superoxide dismutases canbe distinguished:Cu,Zn- SOD,Fe- SOD and Mn-SOD. These three SODs are different in thephylogenetic distribution pattern,prokaryotescontain Mn- SOD,Fe- SOD or both,and Cu,Zn-SODs in the cytosol and peroxisomes of eukaryotesand homologous prote…  相似文献   

10.
InrecentyearsstUdyondevelopingnovelmimicenZymemodelsthathavebothoNOO-decomPositionandO,'(or.OH)dismutaseabilityisaveryactiveresearchfield1'2.Thesemodelsshowverytwrtanteffectinprovidingprotectionfromtissuedamageassociatedwithvariousmpesofinfiammatorydiseases.MetallopoIPhyrinsassuPeroxidedismutase(SOD)mimicshaveshowedtheabilitytocatalysttheseharmfulradicals.Groveandco-workersrePorted[Mn(III)TMPyP]and[Fe(III)TMPyP]whichhaveshowedveryefficientbehaviorasperoxynitritereductaseandcandep…  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

14.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

15.
16.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

17.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

18.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

19.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.  相似文献   

20.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

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