Funding for this research was provided by:
National Natural Science Foundation of China (81602551)
Received: 29 May 2018
Accepted: 25 January 2019
First Online: 11 February 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Nanjing KingMed Diagnostics. The Ethics Committee of Nanjing KingMed Diagnostics concluded that no informed consent was required because the data are anonymized appropriately.
: Not applicable.
: The authors declare that they have no competing interests.
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