Text and Data Mining valid from 2019-06-03
Received: 28 February 2019
Accepted: 13 May 2019
First Online: 3 June 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: 1021). 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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