Funding for this research was provided by:
Beijing Municipal Commission of Health and Family Planning (2018-4-2156)
Article History
Received: 26 June 2018
Accepted: 5 November 2018
First Online: 16 November 2018
Ethics approval and consent to participate
: The current study is approved by Peking University Cancer Hospital Ethics Committee. Written informed consent for participation will be obtained from participants.
: Not applicable.
: The authors declare that they have no competing interests.
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