Text and Data Mining valid from 2019-03-13
Received: 25 December 2018
Accepted: 5 March 2019
First Online: 13 March 2019
Compliance with ethical standards
: This study was approved by the Ethics Committee of The Third Medical Center of Chinese PLA General Hospital. Written informed consent was obtained from each patient or their legal relatives.
: The authors declare that they have no conflict of interest.