Hou, Wenbo
Sun, Xuguang
Feng, Jun
Zhang, Yang
Wang, Zhiqun
Article History
Received: 14 August 2019
Accepted: 4 December 2019
First Online: 19 December 2019
Ethics approval and consent to participate
: The Medical Ethics Committee of the Beijing Tongren Hospital approved the study and the study adhered to the tenets of the Declaration of Helsinki. For this type of study, formal consent is not required.
: Not applicable.
: The authors declare that they have no conflict of interests..