Text and Data Mining valid from 2018-12-01
Received: 23 July 2018
Accepted: 11 December 2018
First Online: 22 December 2018
Ethics approval and consent to participate
: The study has gotten approval from Medical Ethics Committee of Nanfang hospital. Consent to participate is not applicable for this retrospective study.
: This section is not applicable for our study.
: The authors declare that they have no competing interests.
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