controlled study metabolism nonhuman Animals 652 animal 642 priority journal 494 Article 476 animal experiment 372 animal cell 362 article 356 genetics 324 mouse 318 unclassified drug 314 physiology 304 animal tissue 296 Mice 264 female 236 protein expression 232 male 226 human 212 Humans 206 drug effects 202 Female 190 Male 188 chemistry 180 animal model 166 drug effect 154 enzyme activity 144 signal transduction 140 gene expression regulation 138