Text and Data Mining valid from 2019-04-11
Received: 31 October 2018
Accepted: 20 March 2019
First Online: 11 April 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of China-Japan Friendship Hospital. All patient procedures were performed after obtaining written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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