Blood supply and demand.
D001782:Blood Donors / Q000600:supply & distribution*; D001803:Blood Transfusion / Q000592:standards*; D005260:Female; D015658:HIV Infections / Q000635:transmission; D006801:Humans; D008297:Male; D009042:Motivation; D011247:Pregnancy; D017751:Safety Management; D065227:Transfusion Reaction