Received: 24 August 2017
Accepted: 21 June 2018
First Online: 20 July 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of our institute, Peking Union Medical College, Beijing, China, and all experimental procedures involving human subjects have been performed in accordance with the Declaration of Helsinki. All participants signed a written informed consent for participation in this study. Parents consented for minors (those under 16).
: All participants included in this study signed a written informed consent for publication of their medical data and images. Parents consented for minors (those under 16).
: The authors declare that they have no competing interests.
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