controlled study human Humans 616 article 584 priority journal 525 human cell 446 female 354 nonhuman 315 male 299 Female 292 Animals 262 adult 257 Male 242 Article 230 unclassified drug 226 protein expression 192 metabolism 188 animal cell 176 Adult 162 mouse 150 animal 134 Mice 130 clinical article 120 signal transduction 115 animal experiment 114 cell proliferation 112 Middle Aged 111 genetics 109 in vitro study 106 major clinical study 105