Fig. 1.
Experimental schedule. a The study groups. hUCB-MSCs, human umbilical cord blood-derived mesenchymal stem cells; SI, single injection; 3RI, repeated injection with 3-day intervals; 7RI, repeated injection with 7-day intervals. b Time line. C, compression; DC, decompression; W, weeks after the first transplantation; T, transplantation; S, sampling; SEP, somatosensory evoked potential