Correction: Conditioned Medium from Hypoxic Bone Marrow-Derived Mesenchymal Stem Cells Enhances Wound Healing in Mice

• Lei Chen, 
• Yingbin Xu, 
• Jingling Zhao, 
• Zhaoqiang Zhang, 
• Ronghua Yang, 
• Julin Xie, 
• Xusheng Liu, 
• Shaohai Qi