Humans human 308 metabolism nonhuman Animals 247 animal 247 controlled study 196 priority journal 175 animal cell 139 unclassified drug 136 mouse 130 genetics 125 Article 124 Mice 108 article 106 chemistry 100 protein expression 99 human cell 96 animal experiment 93 physiology 89 female 76 pathology 75 signal transduction 68 animal model 66 protein function 63 Female 62 drug effects 58 in vitro study 57 in vivo study 56 gene expression regulation 53