The Code of Federal Regulations (CFR) is the codification of the general and permanent rules and regulations (sometimes called administrative law) published in the federal register by the executive departments and agencies of the Federal Government of the United States.
Title 45 pertains to Public Welfare and is the jurisdiction of the Department of Health and Human Services. Part 46 of Title 45 governs the protection of human subjects.
A complete listing of 45 CFR 46 is available at:
http://www.hhs.gov/ohrp/humansubjects/guidance/45cfr46.html