Funding for this research was provided by:
Japan Society for the Promotion of Science (17H02184)
Text and Data Mining valid from 2020-03-10
Received: 7 December 2019
Accepted: 27 February 2020
First Online: 10 March 2020
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Yamagata University School of Medicine (No. 112 from April 2005 to March 2006, approved on March 13, 2006) and the Hyogo College of Medicine Ethics Committee (No. 3003 in 2018).
: Not applicable.
: The author declares that he has no competing interests.