Funding for this research was provided by:
National Natural Science Foundation of China (81771825)
Beijing Municipal Science and Technology Commission (D171100003017003)
Ministry of Science and Technology China (2017YFC1307904)
Received: 13 November 2019
Accepted: 7 April 2020
First Online: 21 May 2020
Ethics approval and consent to participate
: The study protocol was approved by institutional review board of Tsinghua University School of Medicine and the written consent forms were obtained from all the subjects prior to the initiation of this study.
: Not applicable.
: The authors declare that they have no competing interests.