Funding for this research was provided by:
Japan Society for the Promotion of Science (25870125)
Received: 2 August 2017
Accepted: 8 December 2017
First Online: 16 December 2017
Ethics approval and consent to participate
: The research protocol of this cadaveric study was in compliance with the Helsinki Declaration, approved by the Institutional Review Boards (Research Ethics Committees of Graduate School of Medicine, Chiba University; the reference number #1782) and written consent was obtained for the donation and participate the study before death.
: Not applicable.
: The authors declare that they have no competing interests.
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