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(bĕl) SYMB: B. A unit of measurement of the intensity of sound. It is expressed as a logarithm of the ratio of two sounds of acoustic intensity, one of which is fixed or standard; the ratio is expressed in decibels.


(bĕ-lāy′) To protect with a rope. A rescuer can belay a stokes basket as it is being lowered to a safe position.


(belch) 1. To expel gas from the stomach through the mouth; to eructate. 2. An act of belching; eructation.


(belch′ing) Raising of gas from the stomach and expelling it through the mouth and nose. For belching to occur, there is first an increase in gastric pressure; then the lower esophagus sphincter relaxes to allow equalization of pressure in the stomach and esophagus. Relaxation of the upper esophagus sphincter allows the gas to escape through the pharynx and mouth. SEE: water brash.

 ETIOLOGY: Belching may be caused by gastric fermentation, air swallowing, or ingestion of carbonated drinks or gas-producing foods.

Bell, Sir Charles

(bel) Scottish physiologist and surgeon, 1774–1842.

B. palsy Paralysis of the facial nerve. SYN: Bell paralysis; facial palsy; facial nerve palsy; facial nerve paralysis; facial paralysis; idiopathic facial neuropathy.

 INCIDENCE: Approx. 25 people out of 100,000 experience an episode of facial nerve paralysis yearly.

 ETIOLOGY: Bell palsy is usually caused by a reactivation of herpes simplex virus, but other infections such as syphilis or Lyme disease are sometimes implicated.

 SYMPTOMS AND SIGNS: Paralysis of the facial nerve typically results in an asymmetrical facial appearance. Either side of the face may be affected. The affected patient is unable to raise one side of the mouth to smile or to wrinkle or raise the eyebrow on the same side. This peripheral nerve dysfunction is distinguished from strokes that alter facial movement by the involvement of both the forehead and the mouth. Paralysis of the face caused by strokes usually only limits movement of the oral muscles. SEE: illus.




Asymmetrical smile in patient with Bell Palsy


 DIAGNOSIS: Bell palsy is diagnosed by physical examination. It should be distinguished from ischemic or hemorrhagic stroke, complicated migraine, brain tumors, central nervous system infections, Lyme disease and Guillain-Barré syndrome.

 TREATMENT: Tapering doses of prednisone without antiviral drugs provide the most effective results. In addition, the affected eye should be protected from drying with artificial tears or unmedicated ointments. Some practitioners advise wearing sunglasses during the palsy or patching the eye to protect it ...

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