Funding for this research was provided by:
Ministry of Science and Technology of the People's Republic of China (2016YFC0105207)
Article History
Received: 25 April 2018
Accepted: 4 December 2018
First Online: 17 December 2018
Ethics approval and consent to participate
: The Institutional Review Board (IRB) of Peking Union Medical College Hospital reviewed the protocol. This is retrospective study. The protocol is rational and scientific. The study is in accordance with ethical principles. The IRB thus approve the protocol.The ethical committee process number is S-K450.This is a retrospective study and written human subject consent was unnecessary.
: Not applicable
: The authors declare that they have no competing interests.
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