线粒体与衰老

线粒体是真核细胞内产生生物能源物质－－ATP的细胞器，是自由基生成的最主要部位，也是自由基损伤的最敏感靶部位。从衰老的自由基理论出发，从自由基的生成、自由基的损伤作用等方面综述了线粒体与衰老的关系。     

Electron transfer reactions of piperidine aminoxyl radicals

This review article summarizes the electron transfer reactions of piperidine aminoxyl radicals. Electrochemical studies revealed the single electron transfer nature of piperidine aminoxyl radicals. In solution, piperidine aminoxyl radicals serve as single electron transfer oxidation reagent to react with various biologically interesting molecules such as glutathione, cysteine, ascorbic acid, and amines. The reaction product distribution, reaction kinetics, intermediates, and the reaction features in biological mimic environments including micelles and cyclodextrins were investigated. Oxoammonium salts, the one-electron transfer oxidation products of piperidine aminoxyl radicals, are agents of organic synthesis to selectively generate ketones or di-ketones from alcohols or ketones bearing α-methylene group under mild conditions. The new reactions of oxoammonium salts with aromatic amines, phenols, heterocycles including phenothiazines, papaverine, and bilirubin are also illustrated.     

黄瓜香水提物对自由基损伤心肌细胞的作用

目的观察黄瓜香水提物对自由基损伤的心肌细胞的作用.方法体外培养心肌细胞,以不同浓度的黄瓜香水提物进行干预,测定心肌细胞搏动频率及培养液中乳酸脱氢酶(LDH)的活性,采用MTT法观察黄瓜香水提物对心肌细胞存活率的影响.结果自由基对心肌细胞造成损伤,不同浓度的黄瓜香水提物可减少LDH漏出,增加细胞存活率(P<0.05).结论黄瓜香对自由基损伤的心肌细胞具有保护作用.     

糙米酵素红曲酒的抗疲劳作用

现代社会因为饮酒引发的一系列问题已经严重影响到了人们的正常生活.研究一种低酒精度、口感醇厚的保健酒饮料来代替部分高酒精度的白酒是未来的市场需求,也是人们健康生活的需要.糙米酵素红曲酒是以糙米酵素、大米为原料,利用红曲霉进行发酵研制而成的功能酒.通过糙米酵素红曲酒灌胃小鼠后的体重检测试验、负重游泳试验,爬杆试验、脏器指数检测、血清生化检测以及氧自由基清除试验,考察糙米酵素红曲酒功能性饮料的抗疲劳作用,结果发现糙米酵素红曲酒对小鼠生活状态几乎无任何影响,对小鼠肝、肾、脾脏脏器指数和血清生化检测值无异常,并能延长小鼠负重游泳时间、延长爬杆时间,对氧自由基有一定的清除能力,清除率最高可达12.69％,具有一定的抗疲劳作用.     

长白山植物的抗自由基

用电子顺磁共振方法从长白山出产的二十余种中草药中筛选出能清除活性氧自由基的中草药１６种，其中绝大部分的清除效率大于５０％。此可做为利用其研制抗衰老、抗肿瘤等药物和开发的理论依据。     

Melatonin and cell death: differential actions on apoptosis in normal and cancer cells

Melatonin is a natural compound synthesized by a variety of organs. It has been shown to function as a cell-protective agent. Since 1994, when the first paper was published documenting the role of melatonin in apoptosis, the number of reports in this area has increased rapidly. Much of the research conducted falls into three major categories: first, the role of melatonin in inhibiting apoptosis in immune cells; second, the role of melatonin in preventing neuronal apoptosis and finally, the role of melatonin in increasing apoptotic cell death in cancer cells. The mechanisms whereby melatonin influences apoptosis have not clarified, although a number of mechanistic options have been suggested. Apoptotic cell death is a physiological phenomenon related to homeostasis and proper functioning of tissues and organs; however, a failure in the apoptotic program is related to a number of diseases. The participation of melatonin in apoptosis in numerous cell types and its potential importance in a variety of diseases such as immunodeficiency, neurodegeneration and cancer is summarized in this review.Received 14 November 2002; received after revision 16 January 2003; accepted 10 February 2003     

Effect of CH3OOH on the atmospheric concentration of OH radicals

Methyl hydroperoxide (CH₃OOH, MHP) is known to be a significant sink and reservoir of HO_x and RO_x radicals in the atmosphere. In order to investigate the impact of MHP on the concentration of atmospheric OH radicals, two key gas-phase reactions of MHP, i.e. the reactions with OH radicals and with UV photolysis, have been simulated at temperature of 293±2 K and total pressure of 1.01×10⁵ Pa, using the long path Fourier transform infrared (LP-FTIR) spectrometry. OH radicals are generated by the photolysis of O₃ in the presence of water vapor. Combined with the relative rate method, the reaction rate constant of MHP with OH radicals is determined to be (3.99±0.15)×10^-12 cm³?molecule^-1?s^-1, and thus the atmospheric lifetime of MHP is estimated at 2.9 days. Furthermore, from detailed analysis of the UV photolysis of MHP, the yield of OH radicals is obtained to be 0.91±0.04. Based on the MHP atmospheric lifetime and the yield of OH radicals, it is concluded that MHP plays an essential role in the redistribution of OH radicals in the troposphere.     

破碎、氧化和光照对煤中自由基的影响分析

基于煤炭自燃的自由基反应机理。采用电子自旋共振（ESR）测谱仪，直接测定煤体在破碎、低温氧化和紫外光照射过程中的自由基．结果表明。诸因素均能诱发煤自由基的形成：煤体被破碎地越细小，自由基浓度越大；氧化温度越高，煤自由基浓度越大，125℃之后，煤的自由基浓度明显上升；氧化时间越长，煤自由基浓度越大，但增加的速度比较慢；煤中自由基对紫外光也极其敏感，在刚开始光照和刚撤除光照的前10min内，自由基浓度变化最快．根据实验结果，对煤自燃过程中存在的一些现象作了解释 图4，表1，参11．     

关于环的模糊诣零一幂零性

讨论的环均是结合环未必有恒等元．利用模糊方法推广了诣零，（局部）幂零子环和理想的概念，建立了模糊诣零根及局部幂零根．研究了环的模糊诣零一幂零性问题．