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(ĕk-sīt″ă-bil′ĭt-ē) The property of a cell to generate an electrical impulse. This is a function of the permeability of the cell membrane.

muscle e. In a muscle fiber, the ability to contract by induction. This is a function of the chemical and electrical state of the sarcolemma and the time since a previous stimulus was applied.

reflex e. Sensitivity to reflex irritation.


(ĕk-sīt′ănt) A stimulant.


(ek″sī″tā′shŏn) 1. The act of exciting. 2. The condition of being stimulated or excited.

direct e. Stimulation of a muscle physically or by placement of an electrode in it.

indirect e. Stimulation of a muscle via its nerve.

excited skin syndrome

The eruption of inflammatory rashes far from an initial exposure to an allergen or irritant. The syndrome can cause false-positive reactions during allergy patch testing.

excited state

The new state produced when energy is added to a nucleus, atom, or molecule. The energy is added by the absorption of photons or by collisions with other particles.


Causing excitement.


(ek-sīt″ŏ-mōt′or) [L. excitare, to arouse + motor] Causing or capable of causing muscular activity.


(ek-sīt′ŏr) [L. excitare, to arouse] Something that incites to greater activity, e.g., a nerve that when stimulated arouses greater action in the area or part it supplies. SYN: stimulant.


(ek-sīt″ŏ-toks′ĭn) [excite + toxin] A neurotransmitter (such as glutamate or aspartate) that can cause brain cell injury or death if its action is unabated. Brain damage is mediated by excitotoxins during prolonged seizure activity and stroke.


(ĕks-kloo′zhŏn) [L. exclusio, a shutting out] 1. Shutting off or removing from the main part. 2. In medical insurance programs, a list of specific hazards, perils, or conditions for which the policy will not provide benefits or coverage payments. Common exclusions include preexisting conditions such as cancer, heart disease, diabetes, hypertension, a pregnancy that began before the effective date of the policy, self-inflicted injuries, combat injuries, plastic surgery for cosmetic reasons, and on-the-job injuries covered by workers' compensation.

competitive e. The prevention of bacterial infection (esp. in the gastrointestinal tract) by native bacteria in the microbiota SYN: barrier effect; colonization resistance. exclude (ĕks-klood′), v.


(ĕks″kloo-sĭv′ĭ-tē) [Med. L.] In the pharmaceutical industry, patent protection for drug manufacturers who may produce a therapeutic agent without competition from other drug suppliers.



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