Article History
Received: 22 December 2019
Accepted: 4 June 2020
First Online: 8 June 2020
Ethics approval and consent to participate
: All the documentation and procedures comply with Good Clinical Practice (GCP), Human Ethics Protocol Rules and related Chinese laws. The CHNS project was approved by the office of human research ethics of the University of North Carolina at Chapel Hill and the Human & Clinical Research Ethics Committee of China-Japan Friendship Hospital.
: Written informed consent for publication was obtained from all participants.
: All authors declare that they have no conflicts of interest and are in agreement with the content of the manuscript.