1Jiyuan Shi and Ya Gao did equal to this work
Correspondence to: Jinhui Tian, Evidence-Based Medicine Centre, School of Basic Medical Sciences, Lanzhou University, No.199, Donggang West Road, Lanzhou City, 730000, Gansu Province, China. ( Email:tianjh996@163.com).
Correspondence to: Junhua Zhang, Evidence-Based Medicine Center, Tianjin University of Traditional Chinese Medicine, No. 312 Anshanxi Street, Nankai District, Tianjin 300193, China.( Email:zjhtcm@foxmail.com.)