Animals priority journal protein expression nonhuman 584 controlled study 503 article 499 animal cell 343 Mice 323 animal experiment 290 mouse 285 animal tissue 240 Humans 238 Female 232 human 204 female 199 unclassified drug 196 Male 166 animal model 165 male 159 animal 158 rat 153 Rats 152 protein function 143 metabolism 136 signal transduction 134 human cell 104 messenger RNA 101 cell proliferation 99 enzyme activity 97 RNA, Messenger 94