An international unit (IU) is an internationally accepted amount of a substance. This type of measure is used for the fat-soluble vitamins (such as vitamins A, D and E) and certain hormones, enzymes, and biologicals (such as vaccines).
The definition of an international unit (IU) is generally arbitrary, technical, and eminently forgettable. For example, an IU of vitamin E is the specific biological activity of 0.671 milligrams of d-alpha-tocopherol. Nonetheless, most IUs are quite handy and helpful in use as a means of standardizing measures.
All international units are officially defined by the International Conference for Unification of Formulae.
- United Network for Organ Sharing (UNOS)
The nationwide umbrella for transplantation organ sharing in the U.S. United Network for Organ Sharing states that it is “a private, not-for-profit, membership corporation qualified as a charitable organization under section 501 (c)(3) of the IRC.” United Network for Organ Sharing administers the national Organ Procurement and Transplantation Network (OPTN) and the U.S. Scientific Registry […]
- United States Public Health Service
The part of the Department of Health and Human Services (HHS) that is responsible for the public health of the US population. Abbreviated USPHS. USPHS administers a number of important health agencies, including the Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and the National Institutes of Health (NIH).
- Universal colitis
Ulcerative colitis that involves the entire colon (the large intestine). Ulcerative colitis itself is a relatively common disease involving inflammation of the large intestine (the colon). The cause is unknown. It is a form of inflammatory bowel disease and has some similarity to a related disorder, Crohn’s disease. The lower end of the colon (the […]
- Universal donor
A person who is type O in the ABO blood group system and negative for RhD blood group antigen and can donate blood to all recipients.
United Network for Organ Sharing.