抗氧化系统与运动性疲劳恢复

运动强度增大、运动时间延长或因某些疾病,生物体内的自由基会急剧增多并由此引起的脂质过氧化对机体产生损害,结果导致机体免疫功能下降,运动性疲劳和损伤发生。生物机体自身内存有内源性抗氧化系统,含有多种抗氧化剂,是自由基的清除者。为了预防和缓解运动性损伤和疲劳的发生,抗氧化剂的外源性补充也具有积极的意义。本文就人体的抗氧化系统对自由基的清除以及缓解运动性疲劳进行相关综述。     

The biochemistry of human senescence

Summary With controlled diet, exercise including yoga and meditation, the ageing process can be to some extent slowed down. However, immortality is biochemically impossible to achieve in natural organisms, including bacteria.     

吗丙嗪对兔和人红细胞脂质过氧化的抑制

Lipid peroxide (LPO) plays pivotal roles in the process and development of many diseases. In this work, we studied the inhibitory effect of probimane (Pro), a Chinese anticancer agent, on erythrocyte LPO and the interaction of Pro with sialic acids (sia). Malondialdehyde (MDA) of erythrocytes activated by hydrogen peroxide was measured. Pro was found to inhibit the product of LPO induced by hydrogen peroxide in a non-enzyme system of both rabbit and human erythrocytes in the absence of doxorubicin. Sia were     

Form and sound similarity effects in kanji recognition

Four experiments are reported here to address the question of whether figurative and phonological processing based on sub-word components (radicals) interact in the recognition of Japanese kanji characters. A delayed matching task was used in which two briefly exposed source characters (e.g., ), each made up by two radicals, were followed by a probe character (e.g., ) which in critical conditions was different from the source characters. The task of the subject was to decide whether the probe was one of the two source characters. When a probe was figuratively similar to the source display, the homophonic relatedness between source and probe characters elicited more false responses to the probe. However, no homophony effect was found when the probe was dissimilar to the source display. Further, the false alarm rates in the homophone condition with figurative similarity was shown to be sensitive to proportion of homophonous trials in negative sets. The results suggest that phonological information of both whole character and of components was automatically activated despite experimental tasks in which subjects were given little incentive to execute phonetic processing. It is concluded that the interaction of figurative and phonological processing is due to mutual activation of the whole character and its radical(s) in the process of word identification in kanji. The results are considered within an interactive-activation framework with fore- and background activation device in multilevels.     

氨基酸清除活性氧自由基作用的研究

分别采用Ｘ－ＸＯＤ－Ｌｕｍｉｎｏｌ的Ｏ２＾－产生模型和Ｖｃ－Ｃｕ＾２＋－Ｈ２Ｏ２－酵母多糖的ＯＨ产生体系，以还原型谷胱甙肽（ＧＳＨ）作为参照，用化学发光法研究了１９在酸对活性氧自由基的清除能力，证实了氨基酸普遍具有生物抗氧化活性，其抗Ｏ２＾－的有效浓度范围在１０＾－２￣１０＾－４ｍｏｌ／Ｌ，比ＧＳＨ高出二个数量级。     

不同强度游泳训练对雄性小鼠生精能力的影响

摘要：目的：观察不同强度长期游泳训练对雄性小鼠生殖系统生精能力的影响及意义。方法：将雄性实验小鼠随机分为普通强度训练组、高强度训练组和正常对照组。各训练组按照设计的游泳训练方案进行运动训练,正常对照组常规饲养,训练周期结束后,进行各组小鼠激素测定、生化指标、睾丸指数、精子质量检测和生精小管形态学观测,综合评价生精能力。结果：与正常对照组相比较：普通强度训练组睾丸组织SOD含量下降、NOS含量升高,精子活率下降,差异有统计学意义（P<0.05）,高强度训练组血清T水平下降、睾丸组织SOD含量下降、MDA含量上升、NO和NOS含量上升、精子活率下降,差异有统计学意义（P<0.05）;与普通强度训练组相比较：高强度训练组睾丸组织NO和NOS含量上升,差异有统计学意义（P<0.05）。光镜下观察：正常对照组睾丸生精小管间紧凑,间质组织丰富,生精小管边界完整、无萎缩或塌陷,生精细胞之间排列紧密,上皮层次清晰,支持细胞清晰可见,管腔中有较多已分化成熟的精子;普通强度训练组,间质组织和生精小管与正常对照组差异不明显,没有明显的组织病变特征。高强度训练组,生精小管上皮次级精母细胞层数略有减少,精子细胞数目相对减少。结论：高强度长期游泳训练可导致实验动物体内激素水平改变和相关生化指标改变等,从而造成雄性小鼠精子质量的下降;普通强度长时间游泳训练对雄性实验动物血清相关激素水平,睾丸组织生化酶类及发育情况和精子质量也产生了一定影响。     

湍流作用下空化泡的动力学分析和溃灭瞬间自由基产量计算

基于Gilmore空化泡动力学方程,考虑液体黏性、表面张力、可压缩性、水分子扩散及导热影响,建立湍流作用下孔板空化器下游流场的空化泡动力学模型。采用四阶龙格-库塔法对该空化泡动力学模型进行数值求解,再现空化泡沿流动方向的生长、溃灭和反弹过程。采用基于稳态平衡假设的FactSage软件,以数值求解获得的空化泡内温度、压力和水分子数作为输入参数,计算和分析溃灭瞬间空化泡内的分解产物尤其是具有强氧化性的羟基自由基产量。     

Changes in antioxidant enzyme levels and DNA damage during aging

Multiple mechanisms underlie the human aging process, but interest continues in the role that free radicals and antioxidants may play. The concentrations of lymphocyte free radical generation (O₂ ⁻& H₂O₂), DNA damage and antioxidant enzyme levels (glutathione Stransferase, superoxide dismutase and catalase) were evaluated in 110 healthy individuals with an age range of 20–80 years. The antioxidant enzyme levels were significantly less in very old age when compared to young. Moreover, the levels of free radical concentration and DNA damage were increased in the same age group with respect to younger group. Cigarette smoking had a positive relation with free radicals and DNA damage, and inverse relation with antioxidants. On the other hand, body mass was found to have positive relation with free radical generation only. The data indicate that depletion of antioxidant enzyme levels would render the older people more susceptible to free radical stress and DNA damage.     

力竭游泳后大鼠端脑自由基代谢动态变化研究

探讨力竭游泳后即刻、２４ｈ、４８ｈ大鼠大脑组织自由基代谢的动态变化,为力竭运动后大脑组织的恢复提供实验依据。结论：力竭游泳可激活大鼠大脑组织抗自由基氧化酶ＳＯＤ活性,加快脑组织自由基的清除速率,减少自由基代谢产物ＭＤＡ的堆积,减弱因力竭游泳产生的自由基对脑组织细胞的损伤,表明大脑组织有较强的抗自由基损伤能力;力竭游泳引起大鼠端脑组织内ＧＳＨ－ｐｘ活性下降,表明力竭游泳使大脑组织细胞磷酸戊糖代谢作物     

S863天然果蔬饮料对力竭运动小鼠肝脏自由基代谢及超微结构的影响

为研究S86 3天然果蔬饮料对小鼠肝脏自由基代谢及耐力运动能力的影响 ,本实验采用小鼠力竭游泳为运动疲劳模型 ,将 10 0只成年健康雄性小鼠随机分为对照组、实验组、对照游泳组和实验游泳组。观察各组小鼠肝脏超氧化物歧化酶 (SOD)活性和丙二醛 (MDA)含量及肝脏超微结构的变化。实验结果表明 :实验游泳组小鼠的游泳时间比对照游泳组小鼠的游泳时间显著延长 (P <0 0 0 1)。实验组小鼠肝脏超氧化物歧化酶 (SOD)活性明显高于对照组 (P <0 0 5 ) ,丙二醛 (MDA)含量则显著低于对照组 (P <0 0 1)。实验游泳组与对照游泳组小鼠肝脏超氧化物歧化酶 (SOD)活性无显著性差异 (P >0 0 5 ) ,而丙二醛 (MDA)含量则与对照游泳组有非常显著的差异 (P <0 0 0 1) ,肝脏超微结构的变化也表现出同样的规律。这些结果表明 :S86 3天然果蔬饮料对超氧阴离子自由基具有极强的清除能力 ,能有效抑制脂质过氧化反应 ,具有极佳的抗氧化性能