Funding for this research was provided by:
National Research Foundation of Korea (2014R1A5A2010008)
Text and Data Mining valid from 2018-06-04
Received: 25 January 2018
Accepted: 24 May 2018
First Online: 4 June 2018
Ethics approval and consent to participate
: The current study was approved by the institutional review board at Dongsan Hospital, Keimyung University School of Medicine. The need for written informed consent was waived. This study was conducted in compliance with the Declaration of Helsinki.
: The authors state that they have no competing interests.
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