title: Stability of S9 during frozen storage in Salmonella/S9 assays.
mesh_terms: D000818:Animals; D005615:Freezing; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D009152:Mutagenicity Tests; D051381:Rats; D012486:Salmonella typhimurium / Q000235:genetics; D014021:Tissue Preservation