Periostin Promotes Neural Stem Cell Proliferation and Differentiation following Hypoxic-Ischemic Injury. di Si-Min Ma, Long-Xia Chen, Yi-Feng Lin, Hu Yan, Jing-Wen Lv, Man Xiong, Jin Li, Guo-Qiang Cheng, Yi Yang, Zi-Long Qiu, Wen-Hao Zhou