Fig. 10

TEM images of silk gel implants observed at day 4 (a), 12 (b), 16 (c), 18 (d) and 20 (e, f). The inner cell density of the biomaterial increased over time (a–c), at day 18 and 20, only little silk fibroin gel was observed while blood vessel structure with endothelial and red blood cells was observed; *residual silk gel implants, arrows residual blood vessel