Received: 1 December 2017
Accepted: 15 October 2018
First Online: 13 November 2018
Ethics approval and consent to participate
: All patients gave written informed consent, and the study was approved by the Institute of Review Board in Taipei Veterans General Hospital (VGHIRB No: 96–12-42A). The protocols of this study were consistent with the ethical guidelines provided in the 1975 Helsinki Declaration.
: Not applicable.
: The authors declare that they have no competing interests.
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