title: "Virus-free" renal tumors obtained from prehibernating leopard frogs of known geographic origin.
mesh_terms: D000230:Adenocarcinoma / Q000209:etiology* / Q000382:microbiology / Q000473:pathology; D000818:Animals; D001001:Anura; D006605:Hibernation; D006652:Histological Techniques; D007680:Kidney Neoplasms / Q000209:etiology* / Q000382:microbiology / Q000473:pathology; D008854:Microscopy, Electron; D008910:Minnesota; D012621:Seasons; D014780:Viruses / Q000302:isolation & purification*