Funding for this research was provided by:
National Basic Research Program of China (973 Program) (No. 2016YFC1306105, No.2017YFC1309900)
Fundamental Research Funds for Central Universities of the Central South University (2019zzts818)
Text and Data Mining valid from 2020-04-22
Received: 4 October 2019
Accepted: 18 March 2020
First Online: 22 April 2020
Ethics approval and consent to participate
: The research protocol was approved by the Ethics Committee of the Second Xiangya Hospital, Central South University, China. All procedures performed in studies involving human participants were in accordance with the ethical standards of the Institutional Research Committee and with the 1964 Helsinki declaration and its later amendments, or in accordance with comparable ethical standards. All enrolled students signed an official written consent form that had been approved by the Ethics Committee.
: Not Applicable.
: The authors declare that they have no conflict of interest.