Ma, Ran
Chen, Guan-Hong
Zhao, Liu-Jing
Zhai, Xi-Cheng
Article History
Received: 11 December 2017
Accepted: 19 February 2018
First Online: 5 March 2018
Author contributions
: RM and GHC conceived the study design. LJZ and XCZ performed the study, collected the data, and contributed to the study design. LJZ and XCZ prepared the manuscript. RM, GHC, and XCZ edited the manuscript. All authors read and approved the final manuscript.
: None
: Not applicable
: The authors declare that they have no competing interests.
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