【摘要】 为进一步探讨心脏直视手术患者血浆、心肌组织氧自由基变化及临床意义，对１５例心脏直视手术患者血浆、心肌组织丙二醛（ＭＤＡ）含量及超氧化物歧化酶（ＳＯＤ）活性进行测定，并对心肌组织进行超微结构观察。结果表明，血浆ＭＤＡ含量在体外循环过程中逐渐升高，心脏复跳后较缺血期更明显，而血液ＳＯＤ活性呈下降趋势；心肌组织缺血再灌注后ＭＤＡ含量较心脏停跳前、停跳后明显增加，而ＳＯＤ活性降低。心脏复跳后，心肌组织超微结构损害较停跳后更明显．这一结果提示，心肌组织氧自由基的产生主要是在再灌注期，是心肌缺血再灌注损伤的重要原因。更多还原

【Abstract】 In order to observe the changes and clinical significance of oxygen free radicals in patients with open heart surgery,the content of malondialdehyde(MDA)and the activity of superoxide dismutase(SOD)in plasma and myocardium were measured in 15 cases and the myocardial ultrastructure was also observed.The results showed that the content of plasma MDA increased during cardiopulmonary bypass,especially during reperfusion,on the other hand activity of SOD decreased.The content of myocardial MDA markedly increased during reperfusion than during myocardial ischemia.Myocardial ultrastructure showed more damage in the reperfusion than in the ischemia period.The result revealed that myocardial oxygen free radicals are formed primarily during reperfusion period, which is responsible for myocardial damage during reperfusion.更多还原