Text and Data Mining valid from 2019-04-11
First Online: 11 April 2019
Compliance with ethical standards
: The authors declare that there are no conflicts of interest.
: All procedures followed were in accordance with the national health and Family Planning Commission “biomedical research involving human ethics review approach” (the National Health Commission Order No. 11), “Helsinki declaration” of the World Medical Association, the ethical principle of CIOMS “International Ethical Guidelines for Biomedical Research Involving Human Subjects”. Informed consent was obtained from all patients for being included in the study.