Text and Data Mining valid from 2018-05-02
Received: 2 March 2018
Accepted: 25 April 2018
First Online: 2 May 2018
Ethics approval and consent to participate
: The protocol was approved by the ethics committees of Keio University and affiliated hospitals. Written informed consent was obtained from each patient.
: Each patient provided written informed consent to analyze and publish his/her data.
: The authors declare that they have no competing interests.
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