enzyme isolation article 22 nonhuman 20 controlled study 18 unclassified drug 16 priority journal 14 enzyme activity 12 Animals 10 Mice 6 Phospholipase A2 6 Rabbits 6 catalysis 6 enzyme purification 6 mouse 6 phospholipase A2 6 snake venom 6 Antibodies IgG 4 Antibody Specificity 4 Antivenins 4 Buffers 4 Candida antarctica 4 Chromatography, Affinity 4 Crotalus 4 Crotalus durissus terrificus 4 Crotoxin 4 Culture Media 4 Freund adjuvant 4 Glycoside Hydrolases 4 Hemolysis 4 Hydrogen-Ion Concentration 4