Escalated regeneration in sciatic nerve crush injury by the combined therapy of human amniotic fluid mesenchymal stem cells and fermented soybean extracts, Natto oleh Pan Hung-Chuan, Yang Dar-Yu, Ho Shu-Peng, Sheu Meei-Ling, Chen Chung-Jung, Hwang Shiaw-Min, Chang Ming-Hong, Cheng Fu-Chou