Funding for this research was provided by:
Tangshan Science and Technology Innovation Team Project (18130220A)
Text and Data Mining valid from 2019-04-16
Received: 12 December 2018
Accepted: 9 April 2019
First Online: 16 April 2019
Compliance with ethical standards
: The authors declare that they have no conflicts of interest.
: The study was approved by the Ethical Committee of Human Research of our hospital (No: RMYY-YWLL-2018-15). The trial was also registered prior the participant enrollment at ExternalRef removed (identifier: ChiCTR1800017768).
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in this study.