Funding for this research was provided by:
Capital Characteristic Clinical project of Beijing Municipal Science & Technology Commission (No. Z161100000516009)
Article History
Received: 23 December 2019
Revised: 30 April 2020
Accepted: 1 July 2020
First Online: 11 July 2020
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: Our retrospective study was approved by the institutional ethics committee of the China-Japan Friendship Hospital.