Text and Data Mining valid from 2019-02-26
Received: 15 December 2018
Accepted: 11 February 2019
First Online: 26 February 2019
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Our protocol was approved by the Institutional Review Board of Saitama Medical University (reference number 17-102), who determined that informed consent was not necessary.
: Not applicable
: The authors declare that they have no competing interests.
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