Funding for this research was provided by:
National Science and Technology Major Project of the Ministry of Science and Technology of China (2017ZX09304029-006)
Received: 20 April 2020
Accepted: 7 September 2020
First Online: 14 September 2020
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Peking University First Hospital and all procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000. All the parents or legal guardians of children signed written informed consent forms.
: Consent for publication were obtained from all parents or legal guardians.
: The authors declare that they have no competing interests.