Funding for this research was provided by:
Grant of the Japan Sports Medicine Foundation, 2013
Text and Data Mining valid from 2019-02-02
Received: 13 July 2018
Accepted: 21 January 2019
First Online: 2 February 2019
Ethics approval and consent to participate
: This study was reviewed and approved by the official ethical review board at University of Tsukuba Hospital (Approval number: H26–120). Prior to drawing blood, written informed consent was obtained from each donor.
: Not applicable.
: The authors declare that they have no competing interests.
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