An inhibitory factor associated with the mammary tumour agent in mice.
D000818:Animals; D066298:In Vitro Techniques; D008325:Mammary Neoplasms, Experimental / Q000209:etiology*; D051379:Mice; D008892:Milk; D009858:Oncogenic Viruses / Q000302:isolation & purification*; D014461:Ultracentrifugation