卫生公益性行业科研专项201202010;蚌埠医学院校企产学研合作项目byhx14001资助 Supported by the Specific Research Project of Health Pro Bono Sectors, National Health and Family Planning Commission of the People’s Republic of China201202010;the Produc-tion-Study-Research Cooperation Project Being from Bengbu Medical Collegebyhx14001