Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android. Learn more here!

Delaney clause

(dĕ-lā′nē) [After an amendment in 1958 made by James Delaney, Congressman from New York] A clause in the U.S. Food, Drug, and Cosmetic Act that bans any additive that causes cancer when it is consumed by animals or humans.

de la Tourette

SEE: under de la Tourette, Georges Gilles.

delayed cord clamping

Waiting between 30 and 180 seconds to clamp the umbilical cord after delivery of a newborn. The delay increases the transfusion of cord blood to the newborn, increases the newborn’s hemoglobin levels, decreases the likelihood of intraventricular bleeding, and may reduce neonatal sepsis.

delayed hypersensitivity reaction

A localized skin response mediated by T cells, which occurs 24 to 72 hr after injection of a specific antigen to which the person has been previously sensitized. It is used routinely to screen for tuberculosis infection through injection of purified protein derivative of Mycobacterium tuberculosis. In patients with immunodeficiency, common microbial antigens to which most people have been exposed, such as diphtheria, tetanus, measles, or Candida, are used to determine the presence of defects in T-cell–mediated immunity (CMI). If patients do not develop induration at the site, indicating a positive response to the antigen, a CMI defect is present. Delayed hypersensitivity is a type IV hypersensitivity reaction mediated by cytokines released by macrophages and helper T cells. SYN: nonimmediate allergic reaction.

delayed reaction

A reaction occurring a considerable time after a stimulus, esp. a reaction such as a skin inflammation occurring hours or days after exposure to the allergen.


(dē-lĕd) To remove lead from the body or a tissue. SEE: chelate.


(dĕl″ĕ-tē′rē-ŭs) [Gr. deleterios] Harmful.


(dē-lē′shŭn) In cytogenetics, the loss of a portion of a chromosome.


Having a fine, fragile structure.


(dē-lĭm″ĭ-tā′shŭn) [L. de, from, + limitare, to limit] Determination of limits of an area or organ in diagnosis.


(dē-lĭn′kwĕnt) 1. Someone, esp. a juvenile, whose behavior is criminal or antisocial. 2. Of a criminal or antisocial nature. 3. Overdue or late.


(dĕ″lĭ-kwĕs′ĕns) The process of becoming liquefied or moist by absorbing of water from the air. Ordinary table salt has this property. deliquescent, adj.


(di-lir′ē-ŭm) [L. delirium, madness, insanity] An acute, reversible state of disorientation, inattention, and confusion.

 INCIDENCE: Delirium is exceptionally common among older and hospitalized patients. It is found (in different surveys) in as few as ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.