Objective To evaluate the effects of low dose intravenous minocycline postconditioning on myocardial ischemia-reperfusion injury in rat,and to investigate the possible mechanisms. Methods Forty-eight male wistar rats were randomly divided into four groups:sham-operation (SO)group,ischemia-reperfusion(IR)group,low-dose minocycline(3 mg/kg,LM)group and high-dose minocycline(10 mg/kg,HM)group. The rat model of myocardial IR was established by occlusion of the left anterior descending coronary artery for 45 minutes and reperfusion for 120 minutes.After the reperfusion,the parameters of haemodynamics were recorded;creatine kinase MB(CK-MB),cardiac troponin-I(cTn-I),malond-ialdehyde(MDA),superoxide dismutase(SOD)in serum and myocardium,myocardial apoptosis index(AI)and the myocardial tissue morphology were determined. Results Compared with IR group,LM and HM treatment significantly reduced the levels of CK-MB form,cTn-I,AI and MDA, lowered LVEDP,enhanced LVSP and ±dp/dtmax,elevated the activity of SOD in serum and myocardium(P<0.05). The effect of HM is stronger than LM on these above mentioned indicators,but the difference was not statistical significance(P>0.05). Conclusion LM postconditioning can protect against myocardial IR injury,and the protective effect may be related to the scavenging of oxide free radical,which further restrain the reac-tion of lipid peroxidation and apoptosis.

Objective To investigate the current status of moral distress in clinical nurses,and analyze its influential factors.Methods A total of 240 clinical nurses were recruited by stratified sampling method.They were investigated with general situation questionnaire and moral distress scale.Results The average score of moral distress was (2.66±0.41).Multiple linear regression analysis showed that department of work and qualification were influencing factors on moral distress of clinical nurses.Conclusions This study found that nurses' moral distress was above the middle level.Some targeted measures should be taken by nursing managers,in order to help decrease nurses' moral distress.