Funding for this research was provided by:
Foundation for Promotion of Material Science and Technology of Japan (18K16772, 16K11142, 18K09262, 16K11091, 18K16801, 18K09230, 17K11239)
Text and Data Mining valid from 2019-04-29
Received: 4 February 2019
Accepted: 15 April 2019
First Online: 29 April 2019
Ethics approval and consent to participate
: This study was reviewed and approved by the Institutional Review Board of Yamaguchi University Graduate School of Medicine. Written informed consent to participate was obtained from the participants before the collection of any samples, and the specimens were irreversibly deidentified. All human tissues were handled in accordance with the Tenets of the Declaration of Helsinki.
: Written informed consent for publication was obtained from the participants.
: The authors declare that they have no competing interests.
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