Funding for this research was provided by:
National Natural Science Foundation of China (81670835, 81300745)
Received: 23 October 2017
Accepted: 22 February 2018
First Online: 27 February 2018
Ethics approval and consent to participate
: The study protocol was reviewed and approved by the Ethics Committee of Eye & ENT Hospital of Fudan University, Shanghai, China. Written informed consent was obtained from all participants prior to study enrolment.
: Not applicable.
: The authors declare that they have no competing interests.
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