Funding for this research was provided by:
National Natural Science Foundation of China (81472041)
Text and Data Mining valid from 2018-05-15
Received: 18 August 2017
Accepted: 19 February 2018
First Online: 15 May 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee for Human Subjects of the Peking University Third Hospital. Informed consent was provided by all participating individuals.
: Not applicable
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.