Funding for this research was provided by:
the Japan Society for the Promotion of Science (15K06805)
Yamada Bee Farm
Received: 27 January 2018
Accepted: 10 April 2018
First Online: 2 May 2018
: All animal experiments were approved by The Ethics Review Committee for the Animal Experimentation of Rakuno Gakuen University (Approval Number, VH14A11).
: The authors declare that they have no competing interests.
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