beam


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BEAM

 
brain electric activity map; trademark name for a map of brainwave activity derived from a computerized enhancement of electroencephalographic records.

beam

 [bēm]
a unidirectional, or approximately unidirectional, emission of electromagnetic radiation or particles.
useful beam in radiology, that part of the primary radiation that is permitted to emerge from the tubehead assembly of an x-ray machine, as limited by the aperture or port and accessory collimating devices.
beam splitter a device that reflects light from the output phosphor of an image intensifier to a photographic recording. Called also image distributor.

beam

(bēm),
1. Any bar the curvature of which changes under load; in dentistry, frequently used instead of "bar."
2. A collimated emission of light or other radiation, such as an x-ray beam.
[O.H.G. Boum]

beam

Etymology: ME, beem, tree
1 a bedframe fitting for pulleys and weights, used in the treatment of patients requiring weight traction. See Balkan traction frame.
2 (in radiology) the primary beam of radiation emitted from the x-ray tube.

BEAM

[bēm, bē′ē′ā′em′]
abbreviation for brain electric activity map.

beam

Drug slang
A regional synonym for cocaine.
 
Radiation oncology
A focused stream of particles or electromagnetic radiation which is focused in a single direction or body region as part of a therapeutic regimen.

BEAM

Abbreviation for:
BCNU, etoposide, cytarabine, melphalan (a chemotherapy regimen)
Biomedical Equipment Assessment & Management (Medspeak-UK)
brain electrical activity mapping

beam

(bēm)
1. Any bar with a curvature that changes under load.
2. dentistry Synonym(s): bar (2) .
3. A collimated emission of light or other radiation, such as an x-ray beam.
[O.H.G. Boum]

beam

(bēm)
1. Any bar the curvature of which changes under load; in dentistry, frequently used instead of "bar."
2. A collimated emission of light or other radiation.
[O.H.G. Boum]

beam,

n a stream or approximately unidirectional emission of electromagnetic radiation or particles.
beam, central,
n the center of the beam of roentgen rays emitted from the tube.
beam, useful,
n the part of the primary radiation that passes through the aperture, cone, or other collimator.

beam

a unidirectional emission of electromagnetic radiation. See also x-ray.

external beam therapy
radiotherapy in which the source is at a distance from the patient, e.g. orthovoltage, cesium-137, cobalt-60 or linear accelerator.
beam limitation
restriction of the divergent beam as it appears from the tube window by a lead plate or cone or a light beam diaphragm located at the window.
primary beam
the radiation beam as it passes through the window of the x-ray tube and before it is modified by extra-tube devices.
References in classic literature ?
Then, with a whistling note that rose above the droning of the pit, the beam swung close over their heads, lighting the tops of the beech trees that line the road, and splitting the bricks, smashing the windows, firing the window frames, and bring- ing down in crumbling ruin a portion of the gable of the house nearest the corner.
7000 feet, dipping our beam to an incoming Washington packet.
The landlord had repainted it when Strickland took the bungalow, and unless you knew how Indian bungalows were built you would never have suspected that above the cloth lay the dark, three- cornered cavern of the roof, where the beams and the under side of the thatch harbored all manner of rats, hats, ants, and other things.
Bellevigne de l'Etoile nimbly mounted the transverse beam, and in another minute, Gringoire, on raising his eyes, beheld him, with terror, seated upon the beam above his head.
But before putting him down I had the extremely bad taste to cut off his pigtail and spike it to that beam above his grave, where you may see it at this moment, or, preferably, when warmth has given you leisure for observation.
His gray locks slowly waved on the wind, and glittered to the beam of night.
One could see from the street right into the room with the hog's-leather hanging, which was slashed and torn; and the green grass and leaves about the balcony hung quite wild about the falling beams.
as the ship rolled) a dusty beam of sunlight shone in, and dazzled and delighted me.
A beam ran across over our heads, but not out of reach of our arms and our pickaxes--a beam fast at each end in the ruined wall, with ceiling and flooring all ripped away, and a great gap in the roof above, open to the sky.
just as the sisters arrived here, a monotonous boy in a Scotch cap put his head round a beam on the left, and said, 'Less noise there, ladies
At length we stopped before a very old house bulging out over the road; a house with long low lattice-windows bulging out still farther, and beams with carved heads on the ends bulging out too, so that I fancied the whole house was leaning forward, trying to see who was passing on the narrow pavement below.
I told him I had managed to keep the weight sufficiently well up, as I thought, one-third of the whole being in the upper part "above the beams," as the technical expression has it.