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非生物胁迫下植物体内活性氧清除酶系统的研究进展 总被引：6，自引：0，他引：6
植物受到非生物胁迫时,细胞内活性氧的产生及其清除会失去平衡,活性氧过量积累会导致植物体内氧化胁迫。文章简要概述了在非生物胁迫下,植物体内产生的活性氧使植物体内细胞受到氧化胁迫危害,介绍了活性氧清除酶系统在非生物胁迫中的作用,该清除酶系统主要包括超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）、脱氢抗坏血酸还原酶（DHR）、谷胱甘肽还原酶（GR）和谷胱甘肽过氧化物酶（GPX）。 相似文献
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目的:评估帕瑞昔布对过氧化氢诱导的大鼠原代星形胶质细胞氧化应激状态的保护作用,并初步探讨其作用机制。创新点:首次在大鼠原代星形胶质细胞中证实帕瑞昔布对过氧化氢诱导的氧化应激具有保护作用,且此作用可能与Bax、Bcl-2和BDNF的失调有关。方法:设立如下四组对照:(1)阴性对照组;(2)100μmol/L H_2O_2处理组(处理时间为24 h);(3)80μmol/L帕瑞昔布处理组;(4)160μmol/L帕瑞昔布处理组(第三和第四组先用帕瑞昔布处理24 h,再用100μmol/L H_2O_2处理24 h)。用荧光显微镜观察星形胶质细胞的形态,用MTT法检测星形胶质细胞的存活率,用荧光探针二氯荧光黄双乙酸盐(DCDHF-DA)检测星形胶质细胞内氧自由基的含量,并用碘化丙啶(PI)染色检测细胞的凋亡状态。最后用反转录酶聚合酶链反应(RT-PCR)和蛋白质印迹(Western blot)检测Bax、Bcl-2和BDNF三种蛋白在4组中的表达水平。结论:H_2O_2处理可以导致星形胶质细胞的形态发生改变(图1)和存活率降低(图2),提高星形胶质细胞内的氧自由基水平(图3),同时诱导细胞凋亡(图4)。然而,所有这些变化都可以被帕瑞昔布逆转。此外,我们发现,Bax、Bcl-2和BDNF的表达水平在H_2O_2处理时失调,而在帕瑞昔布预处理时恢复正常。综上所述,帕瑞昔布对H_2O_2诱导的氧化应激具有保护作用。 相似文献
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水分胁迫能够使植物细胞产生大量的活性氧,而植物体内的酶促和非酶促清除系统如不能及时地将其清除,活性氧的产生能力大于清除能力,就会使植物体内的活性氧代谢失调,对植物造成伤害.文中主要介绍了水分胁迫下植物体内活性氧自由基的产生、清除及其与抗旱性的关系,并就活性氧代谢的进一步研究提出了建议. 相似文献
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氧化应激的产生与胞浆内活性氧簇的升高密切相关,过多生成的活性氧簇能够造成脂质过氧化,损伤蛋白质甚至DNA,而这些物质的受损与疾病发生相关,尤其是神经退行性疾病.神经退行性疾病经常被描述为进行性的神经元丢失,伴随神经元或者胶质细胞中出现标志性寡聚体.在神经退行性疾病中,胶质细胞可能以一种抗氧化应激的方式在神经元功能维持以及生存上发挥重要作用.反之,神经元也能够通过不同途径反馈调节胶质细胞.该文主要探讨在亨廷顿舞蹈症中胶质细胞的特点和功能,阐明氧化应激与亨廷顿舞蹈症的关系,概括这三者之间的关系进而论证胶质细胞在亨廷顿舞蹈症中的抗氧化应激保护作用. 相似文献
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一种化学发光新体系测定抗坏血酸的抗氧化性 总被引：5，自引：2，他引：5
基于过氧化氢与Co2 反应产生的羟基自由基(HO·)氧化鸟嘌呤产生化学发光这一现象,研究了抗坏血酸的抗氧化性能.实验结果表明,抗坏血酸能有效地清除羟自由基,对鸟嘌呤的氧化损伤具有保护作用.该发光体系将能被用于抗羟基自由基药物的筛选. 相似文献
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活性氧代谢与植物的抗逆性 总被引：11，自引：0，他引：11
简述了植物体内活性氧的产生及其主要部位,活性氧对膜脂过氧化的启动以及活性氧对细胞膜系统结构的损伤,着重讨论了活性氧的清除与植物的抗逆性之间的关系,认为在各种逆境胁迫下,植物体内酶促与非酶促系统对活性氧的清除从而增强了植物的抗逆性,同时,应用一些外源新型植物生长调节剂可有效促进酶促系统清除活性氧,更好地增强植物对逆境的忍耐力。 相似文献
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邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
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YANGShiguo 《重庆大学学报(英文版)》2004,3(1):86-88
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex. 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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GUO Bao-feng Xiao Da-wei 《重庆大学学报(英文版)》2005,4(3):129-133
Using virtual reality for interactive design gives a designer an intuitive vision of a design and allows the designer to achieve a viable, optimal solution in a timely manner. The article discusses the process of making the Virtual Reality System of the Humble Administrator＇s Garden. Translating building data to the Virtual Reality Modeling Language （VRML） is by far unsatisfactory. This creates a challenge for computer designers to do optimization to meet requirements. Five different approaches to optimize models have been presented in this paper. The other methods are to optimize VRML and to reduce the file size. This is done by keeping polygon counts to a minimum and by applying such techniques as object culling and level-ofdetail switching. 相似文献