Received: 16 March 2019
Accepted: 24 July 2019
First Online: 29 July 2019
Ethics approval and consent to participate
: Written informed consent was obtained from all the patients prior to their enrollment in the study. The study design adhered to the principles of the Declaration of Helsinki and was approved by the ethics committee of China-Japan Friendship Hospital..
: Not applicable.
: The authors declare that they have no competing interests.