Funding for this research was provided by:
National Natural Science Foundation of China (81572917)
Received: 6 March 2019
Accepted: 20 June 2019
First Online: 12 July 2019
Ethics approval and consent to participate
: Ethical approval for the study was provided by the Ethical Committees of Xijing Hospital.
: Not applicable.
: The authors declare that they have no competing interests.