Funding for this research was provided by:
Kikkoman Corporation (X2136)
Text and Data Mining valid from 2018-12-01
Received: 14 October 2018
Accepted: 29 November 2018
First Online: 12 December 2018
Ethics approval and consent to participate
: Prior to beginning the study, the research protocol was approved by the Tokyo Medical and Dental University’s Review Board, and written informed consent was obtained from all participants. All study procedures were performed in accordance with the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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