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allelic gene


Allen Cognitive Level Screen

A standardized method of assessing information processing based on a theory that postulates six levels of cognitive function. It is used widely by occupational therapists.

Allen test

(ăl′ĕn) 1. A bedside test used to evaluate the patency of the arteries of the hand before arterial puncture. The patient elevates the hand and repeatedly makes a fist while the examiner places digital occlusive pressure over the radial and ulnar arteries at the wrist. The hand will lose its normal pink color. Digital pressure is released from one artery (usually the ulnar), while the other, i.e., the radial, remains compressed. If there is normal blood flow through the unobstructed artery, color should return to the hand within 10 sec. The return of color indicates that the hand has a good collateral supply of blood and that arterial puncture of the compressed artery can be safely performed. 2. A procedure to identify the presence of thoracic outlet compression syndrome caused by tightness of the pectoralis minor muscle. With the patient seated, the examiner abducts the involved shoulder to 90° and flexes the elbow to 90°. While palpating the radial pulse, the examiner externally rotates the humerus while the patient actively rotates the head to the opposite side. A diminished or absent radial pulse is indicative of the pectoralis minor muscle’s compressing the neurovascular bundle. This procedure often produces false-positive results. SEE: illus.; thoracic outlet compression syndrome.






(al′ĕr-jĕn) [aller(gy) + -gen] Any substance that causes a hypersensitivity reaction or abnormal immune response. Allergens do not stimulate an immune response in everyone, only in those sensitized to them. Common allergens include inhalants (dusts, pollen), foods (wheat, eggs), drugs (aspirin, serum), infectious agents (e.g., bacteria, viruses), contactants (chemicals, animals), and physical agents (heat, cold). SEE: allergy; antigen; irritation; sensitization; table.

polymerized a. A chemically altered allergen made into a macromolecule, used in immunotherapy to stimulate a blocking antibody response stronger than the allergen’s normal allergic response.


(al″ĕr-jen′ik) Producing allergy. allergenicity (-jĕ-nis′ĭt-ē), n.


(ă-lĕr′jik) Pert. to, sensitive to, or caused by an allergen.

allergic reaction

A reaction resulting from hypersensitivity to an antigen. SEE: allergy for illus.; hypersensitivity.

allergic salute

A colloquial term for wiping the fingers or the hand upward across the nose, a sign of nasal inflammation resulting from allergies.


(al′ĕr-jist) A physician who specializes in diagnosing and treating allergies.



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