Funding for this research was provided by:
the National Natural Science Foundation of China (31170884)
Text and Data Mining valid from 2018-12-01
Received: 17 January 2018
Accepted: 23 November 2018
First Online: 10 December 2018
Ethics approval and consent to participate
: This study was performed in accordance with medical ethical standards and was approved by the Ethics Committee of Nanjing medical University Jiangsu, China.
: Not applicable.
: The authors declare that they have no competing interests.
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