Funding for this research was provided by:
National Natural Science Foundation of China (81302128)
Text and Data Mining valid from 2020-01-13
Received: 15 November 2019
Accepted: 12 December 2019
First Online: 13 January 2020
Ethics approval and consent to participate
: The Ethical Committee of the First Hospital of China Medical University approved the study. The verbal consent was obtained from the patients or their parent/carer during their admission and hospitalization.
: Not applicable.
: The authors declare that they have no competing interests.