Objective: To understand the awareness of sexual knowledge among primary and secondary school students, as well as their attitudes towards school sex education and to provide a reference for school-based sex education. Methods: A total of 5 531 primary and secondary school students were selected from Beijing, Chongqing, Heilongjiang (Harbin and Jiamusi) and Hubei (Wuhan and Xiaogan) by stratified cluster sampling and were investigated with self-reported questionnaire. Results: Sex-related knowledge scored 62.33±19.35, with a pass rate of 61.9%, and the excellent rate 17.5%. Sexual knowledge of junior high school students scored 64.30±19.07, with the pass rate of 64.7%, and the excellent rate 22.0%. A large proportion of primary students reported unaware of pubertal growth and HIV/AIDS-related knowledge, and a large proportion of junior high students unaware of reproductive physiology. Multivariate Logistic regression analysis showed region, grade, gender, and suburban areas were related to the level of sexual knowledge(P<0.05). More than 76.0% primary students and 85.9% middle school students agreed on the importance of school sexuality education. 59.7% of primary school students and 73.3% of junior high school students hoped to include school sexuality education in compulsory education courses; 59.8% of primary school students and 68.3% of junior high school students felt that school sexuality education should be equipped with specialized teachers. Conclusion Chinese primary and secondary school students are lack of sexual knowledge. As students have strong wills to get more information on sexual knowledge, schools should provide them with more comprehensive and effective sex education through appropriate courses and activities.

Objective To analyze the current situation of unplanned reoperation in cardiac surgery and to discuss the management measures of unplanned reoperation.Methods The information of patients undergoing cardiac surgery in a class A tertiary comprehensive hospital during 2018-2022 was collected to analyze the incidence of unplanned reoperation,major ca uses,disease types,surgica l moda lities and Complications.Results A tota l of 3902 patients underwent surgery,of whom 73(1.87%)underwent unplanned reoperation.The main cause of unplanned reoperation was bleeding(50%).The disease types with the highest unplanned reoperation composition ratio were coronary heart disease(38.4%),and the disease types with the highest incidence were dilated cardiomyopathy(11.1%).The average hospitalization cost,the average length of hospitalization,mortality rate and medical dispute rate of patients who had unplanned reoperation were significantly higher than those who did not have unplanned reoperation,the difference was statistically significant(P=0.001).Conclusion The hospital should strengthen the perioperative management of cardiac surgery,focus on supervising disease types and surgical modalities with high incidence of unplanned reoperation,and strictly implement the system of operation classification and the system of reporting unplanned reoperation to ensure the quality of patient surgery.