Text and Data Mining valid from 2020-03-18
Received: 11 December 2019
Accepted: 27 February 2020
First Online: 18 March 2020
Ethics approval and consent to participate
: This study was approved by the Ethical Committee of Linyi People’s Hospital, and the written informed consent was collected from each participant.
: Written informed consent for publication was collected from each participant.
: The authors declare that they have no competing interests.