Chen, Jingjing
Si, Youjiao
Zhao, Kaikai
Shi, Xianglong
Bi, Weiqun
Liu, Shi-en
Hua, Hui
Article History
Received: 16 March 2018
Accepted: 13 December 2018
First Online: 27 December 2018
Ethics approval and consent to participate
: This study was approved by The Ethics Committee of The Affiliated Hospital of Qingdao University. Participants have provided their written informed consent to participate in this study.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.