controlled study metabolism nonhuman Animals 625 animal 615 Article 476 priority journal 472 animal experiment 361 animal cell 343 article 322 genetics 305 mouse 305 unclassified drug 298 animal tissue 288 physiology 287 Mice 251 female 230 male 221 protein expression 219 human 202 drug effects 201 Humans 196 Female 184 Male 183 chemistry 169 animal model 162 drug effect 146 enzyme activity 140 signal transduction 132 gene expression regulation 130