Funding for this research was provided by:
National Science and Technology Major Project (2016ZX10002003, 2016ZX10002008, 2016ZX10002009)
Natural Science Fund of Guangdong Province (2015A030313022)
Received: 6 January 2018
Accepted: 30 April 2018
First Online: 9 May 2018
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. This study was approved by the scientific and ethics committees of the Third Affiliated Hospital of Sun Yat-sen University. Informed consent was obtained from all individual participants included in the study.
: XP, XL, ZM, JH, HD, ZL, XZ, ZF, DX and ZG declare that they have no competing interest.
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