Funding for this research was provided by:
Japan Society for the Promotion of Science (JP17K08736, JP19K16577)
Received: 3 March 2020
Accepted: 30 March 2020
First Online: 7 April 2020
Ethics approval and consent to participate
: This study was approved by the Research Ethics Committee of Yamagata University Faculty of Medicine (2019-S-84) and was performed in accordance with the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.