Text and Data Mining valid from 2019-09-04
Received: 31 March 2019
Accepted: 22 August 2019
First Online: 4 September 2019
Ethics approval and consent to participate
: This study was approved by the ethics committee of The Third Hospital of Hebei Medical University. Informed consent was obtained from all the participants.
: Written informed consent was obtained from each patient to authorize the publication of their data.
: The authors declare that they have no competing interests.