Received: 27 February 2020
Accepted: 20 May 2020
First Online: 15 June 2020
Ethics approval and consent to participate
: This study was approved by the institutional review board of the Chinese People’s Liberation Army General Hospital, Beijing, China. This study has been performed in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.