studies of thymidine incorporation into dna failed to demonstrate a difference between pygmy and normal fibroblasts in their responses to msa alone , but there was a significantly greater thymidine incorporation into the dna of normal fibroblasts when both competence factor ( platelet-derived growth factor ) and progression factors ( somatomedins and growth hormone deficient platelet-poor plasma ) were present in the test medium .
C0012854
dna
C0000702
a