Funding for this research was provided by:
National Basic Research Program of China (973 Program) (2016YFC1300600)
Beijing Municipal Science and Technology Commission (Z151100003915126)
Text and Data Mining valid from 2019-10-26
Received: 14 April 2019
Accepted: 24 September 2019
First Online: 26 October 2019
Ethics approval and consent to participate
: The study was performed in accordance with the ethical standards of the responsible committees on human experimentation and approved by the Institutional Review Board (no. 2011). Informed consent for all examinations was obtained from the patients or their guardians. The protocol in the study strictly followed the rules of the Declaration of Helsinki.
: Not applicable.
: The authors declare no conflicts of interest.