human cell normal human 80 human 62 article 36 controlled study 36 priority journal 36 Human 30 Humans 28 Support, Non-U.S. Gov't 24 male 24 Male 22 Female 18 in vitro study 18 blood and hemopoietic system 16 erythrocyte 14 Adult 12 Dose-Response Relationship, Drug 12 adult 12 female 12 spermatozoon 12 Erythrocytes 10 radioisotope 10 sperm 10 Cell Division 8 Spermatozoa 8 adenosine triphosphate 8 male genital system 8 monocyte 8 protein expression 8 spermatozoon motility 8