Text and Data Mining valid from 2019-01-18
Received: 10 July 2018
Accepted: 7 January 2019
First Online: 18 January 2019
Ethics approval and consent to participate
: This study was approved by the ethical review board of the Kagoshima University Faculty of Medicine (approval number 278).
: Not applicable.
: The authors declare that they have no competing interests.
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