human 577 Article 512 Humans 384 controlled study 371 male 301 female 300 adult 277 article 266 nonhuman 236 chemistry 222 Female 156 unclassified drug 152 Political structure & processes 150 Male 144 metabolism 120 chemical structure 112 Adult 111 Economic systems & structures 111 major clinical study 111 semi structured interview 108 Animals 105 animal 94 human experiment 93 structure activity relation 93 procedures 92 clinical article 88 middle aged 88 genetics 87 Crystal structure 83 priority journal 81