In vivo replacement of the helper virus in Bryan's strain of Rous sarcoma virus by AMV and RPL12 viruses.
D000818:Animals; D001354:Avian Leukosis Virus; D001358:Avian Sarcoma Viruses; D002642:Chick Embryo; D046508:Culture Techniques; D005347:Fibroblasts; D011200:Poultry; D012513:Sarcoma, Experimental / Q000276:immunology*