Funding for this research was provided by:
RENSHU Funding Project of Hunan Provincial People's Hospital (No.RS201702)
Text and Data Mining valid from 2019-08-14
Received: 26 December 2018
Accepted: 31 July 2019
First Online: 14 August 2019
Ethics approval and consent to participate
: The use of laboratory animals, the umbilical cord collection and use procedure were all approved by the Medical Ethical Committee of Hunan Normal University (Approved number: 2017050). All of the donors were given and accepted written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.