【摘要】 以5′-TMP作为DNA的模型,t—NB作为自旋捕集剂,采用ESR方法研究了DNA受γ射线照射产生自由基,以及知母宁、槲皮素、单宁酸、海藻硫酸多糖、云芝多糖和螺旋藻等几种制剂对水溶液中胸腺嘧啶核酸的辐射防护作用。结果表明,受照5′-TMP分子的自旋捕集ESR信号具有典型的特征性谱线,证实存在5′-TMP自由基,且上述几种中药制剂均有捕集自由剂的作用,其中尤以知母宁、单宁酸和槲皮素效果为佳。更多还原

【Abstract】 Free radical induced by r-irradiated DNA , as well as the radioprotection effect on the thymidine solution by chinonin, quercetin, tannic acid, sulfated polysaccha-ride, polysacchariopeptide and spirulina platensis are investigated by using ESR with 5’-TMP as DNA model and t-NB as spin trapping agent. The results show that spin trapping ESR signal of 7-irradiated 5’-TMP molecule has the typical ESR spectrum. The existence of 5’-TMP free radical is also confirmed. The above mentioned chemicals have the effect of trapping free radical, especially chinonic, tannic acid and quercetin.更多还原