Received: 27 November 2018
Accepted: 15 April 2019
First Online: 30 April 2019
Ethics approval and consent to participate
: The study was reviewed and approved by the ethic committee of the Second Xiangya Hospital, Central South University. The approval number was 2016-S022. All the participants provided informed written consents before their enrollment in the study.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.