Funding for this research was provided by:
National Natural Science Foundation of China (71804093)
Natural Science Foundation of Shandong Province (ZR2015HL102)
Shandong Provincial Medical and Health Science and Technology Development Project (2016WS0478)
Text and Data Mining valid from 2019-08-31
Received: 14 January 2019
Accepted: 22 August 2019
First Online: 31 August 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Shandong provincial Qianfoshan Hospital. Written informed consent was obtained from all subjects.
: Not applicable.
: The authors declare that they have no competing interests.