fetal calf serum and platelet-derived growth factor ( pdgf ) , but not transforming growth factor-beta 1 , stimulated primary rat heart fibroblasts and normal human diploid fibroblasts ( ag 1518 ) to contract collagen gels to less than 10 % of the initial gel volume within a 24-h incubation period .
C1366557
transforming growth
C0086418
human