Contributors
Study concept and design: Gang Xu, Feng Liu, Jun Zhao, Min Ye, Congrui Feng, Yuwei Tong, and Wei Ma; Acquisition of data and patient recruitment: Yueping Li, Haiyan Shi, and Fuchun Zhang ; Analysis and interpretation of data: Yudong Hu , Yuluo Chen, and Liuqian Wang; Drafting of the manuscript: Gang Xu, Feng Liu, Jun Zhao, Min Ye, and Congrui Feng; Revising the manuscript: Yuwei Tong and Wei Ma; Approving the final submission: all authors.