Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «R»:
Reaction, vasovagal: See: Vasovagal reaction....
A chronic form of arthritis featuring the following three conditions: (1) inflamed joints; (2) inflammation of the eyes (conjunctivitis); and (3) inflammation of the genital, urinary or gastrointestinal system.
Reactive arthritis is the preferred name for what was called Reit...
Reactive oxygen species
Reactive oxygen species: Species such as superoxide, hydrogen peroxide, and hydroxyl radical. At low levels, these species may function in cell signalling processes. At higher levels, these species may damage cellular macromolecules (such as DNA and RNA) and participate in apoptosis (programmed cell...
Reading frame: One of the three possible ways to read a
nucleotide sequence in DNA or RNA as a series of nonoverlapping triplets, depending upon whether reading starts with the first, second or third base in the sequence. For example: with the nucleotide sequence TGCTGCTGC, the three possible readin...
Reading frame, open
Reading frame, open: See: Open reading frame....
Reading retardation: Reading retardation means impaired
ability to read. Reading retardation is an impairment that may, for
example, reflect mental retardation or cultural deprivation.
Reading retardation is different from dyslexia, a specific reading
disability due to a defect in the brain's (...
Reagent: A substance used to produce a chemical
reaction to detect, measure, produce, etc. other substances....
Reaven syndrome: See: Metabolic syndrome....
Return of the original symptoms when maneuvers or treatment is
Rebound effect: The characteristic of a drug to
reverse effects when the effect of the drug has passed or the patient
no longer responds
Recalcitrant: Stubborn. For example, a recalcitrant
case of pneumonia stubbornly resists treatment....
FDA recalls: The recall of a defective or possibly harmful product by the US Food & Drug Administration (the FDA).
These recalls are often highly publicized in newspapers
and on radio and TV news broadcasts. Recent headlines in major newspapers such as "FDA Orders Peanut Butter Recall" and "FD...
Recent memory: Short-term memory. Also called working memory.
Recent memory is a system for temporarily storing and managing the information required to carry out complex cognitive tasks such as learning, reasoning, and comprehension. Recent memory is involved in the selection, initiation, and term...
Receptor: 1. In cell biology, a structure on the surface of a cell (or inside a cell) that selectively receives and binds a specific substance. There are many receptors. There is a receptor for (insulin; there is a receptor for low-density lipoproteins (LDL); etc. To take an example, the receptor ...
Receptor, chemokine: A molecule that receives a chemokine and a chemokine dock.
A chemokine is a protein that acts as a lure. Chemokines are involved in inflammation, cancer, and infectious diseases. Several chemokine receptors are essential coreceptors for HIV....