article nonhuman 2,695 priority journal 2,410 controlled study 2,084 Animals 1,987 human 1,132 unclassified drug 1,073 male 1,055 female 1,006 Humans 958 Male 924 Female 908 animal 900 animal experiment 850 animal cell 798 metabolism 731 Argentina 605 animal tissue 590 mouse 577 Mice 559 rat 539 physiology 505 chemistry 502 Rats 469 enzyme activity 448 Animalia 446 protein expression 433 Support, Non-U.S. Gov't 418 human cell 412 genetics 389