Animals animal 217 animal experiment controlled study nonhuman 217 physiology metabolism 146 Article 132 priority journal 130 male 122 animal tissue 119 Male 108 mouse 97 article 85 female 82 Mice 75 animal cell 71 Female 68 animal model 66 unclassified drug 57 adult 51 drug effect 50 rat 47 drug effects 44 genetics 44 protein expression 43 human 40 animal behavior 39 Humans 38 Rats 37