国家自然科学基金资助项目81470074;北京市科学技术委员会临床特色课题Z141107002514117;北京市卫生系统高层次卫生技术人才培养项目2014-3-051;北京市科学技术委员会重点研发计划D171100008217005National Natural Science Foundation of China81470074;Clinical Funding from Beijing Municipal Science and Technology CommitteeZ141107002514117;Program for High-quality Health Professionals from Beijing Municipal Commission of Health and Family Planning2014-3-051;Major Program of Beijing Municipal Science and Technology CommitteeD171100008217005