Funding for this research was provided by:
National Natural Science Foundation of China (81801865)
Science and Technology Innovation Fund of Tangdu Hospital (2017LCYJ009)
Natural Science Foundation Research Program in Shannxi Province (2019JM-191)
Text and Data Mining valid from 2019-08-02
Received: 12 May 2019
Accepted: 29 July 2019
First Online: 2 August 2019
Compliance with ethical standards
: The authors declare that they have no competing interests.
: This study was approved by Ethics Committee of Tangdu Hospital of Fourth Military Medical University (Approval number: TDLL-2016234, Approval date: Feb. 26, 2016) and conformed to the principles of the Declaration of Helsinki. Written informed consent was obtained from each participant after study explanation.
: Not applicable.