controlled study human human cell nonhuman priority journal article 196 Humans 188 animal cell 186 Animals 179 mouse 125 protein expression 111 unclassified drug 111 Mice 108 animal experiment 95 animal model 72 female 62 male 61 signal transduction 59 Article 52 in vitro study 51 Cell Line 50 animal 50 animal tissue 47 Female 46 metabolism 46 cell proliferation 45 in vivo study 45 protein function 45 Male 40 Cell Line, Tumor 36