article priority journal protein expression nonhuman 600 controlled study 598 Animals 499 animal cell 335 animal experiment 284 Mice 275 mouse 264 Humans 258 human 255 animal tissue 234 unclassified drug 230 female 228 Female 226 human cell 189 male 184 protein function 163 animal model 162 Male 156 rat 154 signal transduction 142 Rats 140 enzyme activity 121 messenger RNA 118 cell proliferation 116 apoptosis 97 RNA, Messenger 95 Western blotting 92