human human cell controlled study 446 article 409 Humans 389 priority journal 377 nonhuman 220 unclassified drug 192 Animals 180 protein expression 162 animal cell 151 metabolism 130 Article 127 female 123 Female 121 mouse 112 cell proliferation 105 male 105 signal transduction 103 Mice 101 in vitro study 100 Cell Line, Tumor 95 Cell Line 92 Male 92 apoptosis 85 animal experiment 74 animal 72 enzyme activity 69 cell culture 64 protein function 62