AIM To compare the protective effects of norepinephrine preconditioning(NEPC)and ischemic preconditioning(IPC)on myocardial ischemic/reperfused injury in rats in vivo . METHODS Rats were divided into control, ischemia/ reperfusion, classic IPC and NEPC groups. After 20 min reperfusion, several indexes including cardiac function indexes, MDA were tested, the myocardial ultrastr ucture and the injury reaction of catalase observed. RESULTS Both IPC and NEPC could protect myocardial ultra structure, ameliorate left heart function, decrease cardiac MDA content and protect the activity of catalase. CONCLUSION Extra micro norepinephrine preconditioning as a non injury method can mimic the protective effects of classic IPC and shows its clinical values.

Fertility preservation technology provides an effective method for protecting the reproductive resources of patients with malignant tumors.At the same time,it is inevitable to face great ethical dilemmas in the process of technological implementation.From an ethical perspective,this paper sorted out the research on fertility preservation in tumor patients abroad,as well as analyzed the ethical issues faced by tumor patients in the communication decision-making and implementation stages of fertility protection.Specifically,these included informing and discussing the reproductive information and preservation choices of tumor patients,fertility decision-making of adolescent tumor patients,psychological support for fertility in tumor patients,ownership and use rights of reproductive materials and their disposal methods,fairness in the allocation of social health resources and other ethical issues.Combining with the actual situation in China,this paper further discussed how to put forward corresponding countermeasures based on following ethical principles such as favorable without harm,informed consent,cautious application,and ethical supervision,with a view to promoting the further development and application of fertility preservation technology in clinical practice.