article human cell human 884 controlled study 691 Humans 631 priority journal 606 nonhuman 332 Animals 293 unclassified drug 291 protein expression 255 animal cell 222 Female 189 female 183 Mice 168 male 162 signal transduction 159 Cell Line, Tumor 157 mouse 157 cell proliferation 156 Cell Line 150 Male 139 apoptosis 133 metabolism 127 in vitro study 125 enzyme activity 115 protein function 110 Cells, Cultured 97 Western blotting 97 Apoptosis 96 adult 94