Callus Formation in Fractured Femur of Rats Treated with Injection of Human Umbilical Cord Mesenchymal Stem Cell-Conditioned Medium

Figure 2

Histologic images of fracture bone tissue of rats on day 7, 35, and 60 after surgery. On day 7 after the surgery, the soft callus area (triangle) in the control group (a) was narrow than the MSC-CM group (b). On day 35 after the surgery, the soft callus area is still wider on the control group (c), while in the MSC-CM group (d), the hard callus area was dominant. On day 60 after the surgery, in the control group (e), the soft callus area still dominated the bone tissue, while the soft callus area was almost entirely replaced by the hard callus area (star) in the MSC-CM group (f).

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