Text and Data Mining valid from 2019-09-23
Received: 31 October 2018
Accepted: 9 September 2019
First Online: 23 September 2019
Ethics approval and consent to participate
: All subjects provided written informed consents. The study protocol was approved by the Institutional Ethical Committee of Tianjin medical university general hospital.
: Not applicable.
: The authors declare that they have no competing interests.