Funding for this research was provided by:
The Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences (2018PT32029)
Article History
Received: 18 October 2019
Revised: 26 January 2020
Accepted: 10 February 2020
First Online: 15 February 2020
Compliance with ethical standards
:
: All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript.
: Procedures performed in this study were in accordance with the ethical standards of the Peking union medical college hospital and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.