Funding for this research was provided by:
National Natural Science Foundation of China (81400636)
Received: 26 July 2017
Accepted: 12 February 2018
First Online: 21 February 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board (IRB) of the West China Hospital, Sichuan University. Informed written consent was obtained from all individual participants included in the study. All the methods used in this study were carried out according to the approved guidelines.
: Not applicable.
: The authors declare that they have no competing interests.
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