Category: An-An

The surgical treatment of the fetus before birth. Also called prenatal surgery or, most often, fetal surgery. Fetal surgery is done when the fetus is not expected to live long enough to make it through to delivery or to live long after birth unless fetal surgery is performed. For instance, if a fetus has a severe form…

Amnesia in which the loss of memory relates to events that occur after a traumatic event. There is inability to recall new information. Old information can be recalled. Antegrade amnesia may follow brain trauma. Also called antegrade amnesia. This type of amnesia is in contrast to retrograde amnesia in which the lack of memory relates to events…

Forward-moving. As in blood flow. Sometimes synonymous with anterograde. From the Latin ante- + gradior, to step.

 Exceptionally strong or large. After Antaeus, the mythological Greek giant. The son of the earth mother Gaia, Antaeus challenged anyone he encountered to wrestle and always won, since he received strength from his mother, the earth, as long as he was in touch with her. Hercules discovered the secret of Antaeus, lifted him off the…

A substance that acts against and blocks an action. Antagonist is the opposite of agonist. Antagonists and agonists are key players in the chemistry of the human body and in pharmacology.

Originally from South America, a red or yellowish ant of small to medium size that has a severe sting that burns like fire. The sting of a fire ant causes a pustule to form within 24 hours that takes several days to resolve. Fire ant toxin can trigger an allergic reaction, particularly in people allergic to bee, wasp, and yellow jacket stings.…

Pertaining to anoxia, an absence or near absence of oxygen.

The absence, or near absence, of oxygen. Anoxia can injure tissues of the body.

 Not accompanied by ovulation, the release of an ovum (egg) from the ovary. For example, anovulatory menstruation. Synonymous with anovular.

Menstruation without ovulation. The egg stays within the ovary and usually disintegrates but sometimes it is fertilized, resulting in a life-threatening pregnancy within the ovary.