Funding for this research was provided by:
Hunan Province Science and Technology Projec (2014FJ6090)
Received: 23 March 2018
Accepted: 5 August 2019
First Online: 23 August 2019
Ethics approval and consent to participate
: All participants signed informed consent forms, and the Research Ethics Committee of Central South University, China approved this study, reference number is EC20101220005.
: Not applicable.
: The authors declare that they have no competing interests.