Funding for this research was provided by:
National Key R&D Program of China (2016YFC0800703)
the National Natural Science Foundation of China (81330073, 81501635)
Article History
Received: 13 July 2017
Accepted: 30 August 2017
First Online: 5 September 2017
Compliance with ethical standards
: The humane and ethical research principles recommended by Sichuan University were followed in this study. All participants signed the written informed consents before sample collection. Our study design was approved by the medical ethics committee of Sichuan University.
: The authors declare that they have no conflict of interest.