Guarantor of the article: Xiaolong Qi, MD.
Specific author contributions: Qing He, MD, Guo Zhang, MD, Ye Gu, MD, Jitao Wang, MD, Qiyuan Tang, MD, contributed equally to this work. Concept and design: X.Q. Acquisition of data: Q.H., G.Z., Y.G., Q.T., Z.J., C.S., H.Z., Z.C., B.M., D.L., H.H, Y.W., H.L., J.Y., H.P., S.Z., F.L., F.W., W.W., L.L., J.Y., B.X., and X.L. Analysis and interpretation of data: C.L., J.W., G.X., D.X., Y.H., H.Z., and M.L. Drafting of the manuscript: X.Q. and J.W. Critical revision of the manuscript: X.Q. All authors have contributed significantly to the work and fulfill the requirement of authorship.
Financial support: None to report.
Potential competing interests: None to report.