Morioka, S
Sai, K
Omori, E
Ikeda, Y
Matsumoto, K
Ninomiya-Tsuji, J
Article History
Received: 20 June 2015
Revised: 5 October 2015
Accepted: 26 October 2015
First Online: 14 March 2016
Competing interests
: The authors declare no conflict of interest.