Funding for this research was provided by:
National Natural Science Foundation of China (81270711)
Received: 14 March 2019
Accepted: 24 July 2019
First Online: 1 August 2019
Ethics approval and consent to participate
: This study obtained ethical approval from the Medical Ethics Review Board of China Medical University (Shenyang, Liaoning, China). All participants provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.