Funding for this research was provided by:
Research Medical Fund, Faculty of Medicine, Chiang Mai University (Grant Number 066/2559)
Received: 22 December 2017
Accepted: 9 July 2018
First Online: 16 July 2018
Ethics approval and consent to participate
: This study was approved by the research ethics committee of the Faculty of Medicine, Chiang Mai University. Study number: R000015794.All patients provided written inform consent to the study.
: Not applicable.
: The authors declare that they have no competing interests.
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