Text and Data Mining valid from 2019-01-08
Received: 22 June 2018
Accepted: 2 January 2019
First Online: 8 January 2019
: The authors declare that they have no competing interests.
: This study was approved by Medical Ethics Committee of Kanazawa University. The researchers anonymized all of the data, and the need for informed consent was waived by the medical ethics committee.
: Not applicable.
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