Text and Data Mining valid from 2018-12-01
Received: 16 October 2018
Accepted: 28 November 2018
First Online: 7 December 2018
Ethics approval and consent to participate
: Ethics approval was sought and the study was approved by the institutional review board at Shandong Provincial Hospital affiliated to Shandong University. Written informed consent was obtained from all patients.
: All patients involved had given informed consent.
: The authors declare that they have no competing interests.
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