Funding for this research was provided by:
Uehara Memorial Foundation
Kitasato University Research Grant for Young Researchers
Research grants from the Parents’ Association of Kitasato University School of Medicine
Received: 20 February 2018
Accepted: 29 May 2018
First Online: 13 June 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Review Board of Kitasato University (reference number: KMEO B13-113). Consent was obtained from the participants for participation in this study and the extraction and use of their ST.
: The authors declare that they have no competing interests.
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