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(găng′grĭ-nĭs) Pert. to gangrene.


(găn′trē) [Gr. kanthēlios, pack ass] 1. The housing for the imaging source and detectors into which the patient is placed for computed tomography and magnetic resonance imaging. 2. The portion of the radiation therapy machine (linear accelerator, cobalt unit) that houses the source of therapeutic particles.


(gap) 1. An opening or a break; an interruption in continuity. 2. The difference between the expected and the measured concentration of solute in the plasma.

anion g. The difference between the measured cations sodium (Na+) and potassium (K+) and the measured anions chloride (Cl) and bicarbonate (HCO3–). In accordance with the principle of electroneutrality, in any body fluid the number of net positive charges contributed by cations must equal the number of net negative charges contributed by anions. The unmeasured anions include lactate, sulfates, phosphates, proteins, ketones, and other organic acids. In general an anion gap of 10 to 14 mmol/L is normal. An increased value is present in metabolic acidosis.

image The anion gap should be interpreted after measurement of the serum albumin level. Low albumin levels may mask important elevations in the anion gap.

evidence-practice g. The failure of clinicians to adopt proven practices that enhance outcomes for patients. The disparity between usual professional practice and evidenced-based guidelines.

globulin g. The difference between the measured total protein in a sample of blood and the concentration of albumin. It consists of immunoglobulins, acute phase reactant proteins, and proteins that transport chemicals into and out of cells.

health care g. A disparity between health care needs and health care services, esp. as it applies to the medically indigent.

interincisor g. The measured distance between the upper and lower teeth when the mouth is fully opened. Smaller gaps indicate difficulty in opening the mouth, e.g., during attempts at endotracheal intubation.

osmolal g. The difference between the measured osmolality of a body fluid, and the calculated osmolality of the fluid, e.g., for plasma: plasma glucose/18 + blood urea nitrogen/2.8 + sodium*2. A gap is present when the difference exceeds 10 mmol/kg of water. Osmolal gaps are present when unmeasured osmotically active solutes, such as toxins, e.g., methanol or ethylene glycol, are present in the plasma or urine.

gap junction

Minute pores between cells that provide pathways for intercellular communication. Originally described in muscle tissue, they are known to be present in most animal cells.


(gar′dă-sĭl) The trade name for several human papillomavirus (HPV) recombinant vaccines, including Gardasil 9 (a 9-valent vaccine). Four- and two-valent HPV vaccines are also available.

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