Funding for this research was provided by:
National Natural Science Foundation of China (71874104)
China Postdoctoral Science Foundation (2019M652133)
Fund Program for the Selected Post Doctorate in Zhejiang Province (zj20180138)
Program for the Philosophy and Social Sciences Key Research Base of Higher Learning Institutions of Shanxi (201801019)
Planning Project of Shanxi Philosophy and Social Science founded by Shanxi Philosophy and Social Science Planning Office (2018B205)
Text and Data Mining valid from 2019-11-08
Received: 27 April 2018
Accepted: 20 September 2019
First Online: 8 November 2019
Ethics approval and consent to participate
: The subjects were informed about the purpose and process of this study and signed informed consent forms. All study procedures were approved by the Ethics Committee of Shanxi Medical University.
: Not applicable.
: The authors declare that they have no competing interests.