Article animal cell 76 human nonhuman 76 controlled study 71 Humans 55 Animals 50 animal 50 mouse 50 animal experiment 47 human cell 41 animal model 37 male 35 metabolism 35 animal tissue 34 female 30 in vitro study 29 unclassified drug 28 Mice 25 genetics 25 in vivo study 21 protein expression 21 Male 20 drug effect 20 Female 18 Western blotting 16 cell proliferation 16 adult 15 apoptosis 15 chemistry 15