motor unit


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Related to motor unit: Motor unit recruitment

unit

 [u´nit]
1. a single thing; one segment of a whole that is made up of identical or similar segments.
2. a specifically defined amount of anything subject to measurement, as of activity, dimension, velocity, volume, or the like.
3. a distinct part of a hospital, usually having a specific physical location and serving a defined function; see under names of specific units.
Ångström unit angstrom.
atomic mass unit (u) (amu) the unit of mass equal to ¹⁄₁₂ the mass of the nuclide of carbon 12. Called also dalton.
autonomous nursing unit a nursing unit under a decentralized administration system in which the staff is responsible for all aspects of unit functioning.
British thermal unit (BTU) a unit of heat formerly widely used, being the amount necessary to raise the temperature of 1 pound of water from 39° to 40°F., equal to approximately 252 calories.
CH50 unit the amount of complement that will lyse 50 per cent of a standard preparation of sheep red blood cells coated with antisheep erythrocyte antibody.
continuing education unit (CEU) a unit of credit for educational offerings given to professional persons, determined by a professional organization according to a mathematical formula after a thorough review of the program of study, the qualifications of the instructors, and the program objectives.
critical care unit intensive care unit.
electrostatic u's (esu) that system of units that is based on the fundamental definition of a unit charge as one that will repel a similar charge with a force of 1 dyne when the two charges are 1 cm apart in a vacuum.
environmental control unit a computerized system that allows the handicapped individual to operate several different appliances using a keyboard or other input device.
heat unit the amount of heat energy that is produced by one kVp (kilovolt peak) and one mA (milliampere) for one second with single phase, full wave rectified radiographic equipment.
Hounsfield unit an arbitrary unit of x-ray attenuation used for CT scans. Each voxel is assigned a value on a scale in which air has a value of −1000; water, 0; and compact bone, +1000.
intensive care unit see intensive care unit.
International unit (IU)
1. a unit of enzyme activity equal to the amount of enzyme that catalyzes the conversion of one micromole of substrate or coenzyme per minute under specified conditions (temperature, pH, and substrate concentration) of the assay method. Abbreviated U.
2. any of several arbitrary units that have been adopted by international bodies to express the quantities of certain vitamins (A, C, D, and thiamine hydrochloride), hormones (androgen, chorionic gonadotropin, estradiol benzoate, estrone, insulin, progesterone, and prolactin), and drugs (digitalis and penicillin).
Kienböck's unit a unit of x-ray exposure equal to 0.1 erythema dose; symbol X.
motor unit the unit of motor activity formed by a motor nerve cell and its many innervated muscle fibers.
postanesthesia care unit (PACU) a specialty unit in a hospital for giving postanesthesia care (care of patients recovering from anesthesia and intravenous sedation); formerly called recovery room.
radiologic u's units used to measure radiation, including roentgens, rads, rems, and curies.
u's of service (UOS)
1. the number of procedures done by a department.
2. individuals or groups of individuals who are the recipients of nursing care.
short procedures unit (short term care unit) a nursing unit where patients are briefly cared for following a medical or surgical procedure and are then discharged without spending the night.
SI unit any unit of the International System of units (the metric system); see also si units.
step-down unit a nursing unit designated to provide care for patients who are stable enough to be discharged from the intensive care unit but are not yet ready to be cared for on a medical-surgical unit.
Svedberg unit (S) a unit equal to 10−13 second used for expressing sedimentation coefficients of macromolecules.
Svedberg flotation unit (Sf) a unit equal to 10−13 second used for expressing negative sedimentation coefficients of macromolecules that float rather than sink in a centrifuge, e.g., lipoproteins.
terminal respiratory unit the functional unit of the lung, including a respiratory bronchiole, alveolar ducts and sacs, and alveoli; called also primary lobule of lung and primary respiratory lobule.
USP unit one used in the United States Pharmacopeia for expressing potency of drugs and other preparations.

mo·tor u·nit

a single somatic motor neuron and the group of muscle fibers innervated by it.

motor unit

a functional structure consisting of a motor neuron and the muscle fibers it innervates.
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Motor unit

mo·tor u·nit

(mō'tŏr yū'nit)
A single somatic motor neuron and the group of muscle fibers innervated by it.

motor unit

a motor neurone and its associated muscle fibres.
Motor unit, from spinal cord to neuromuscular junction.

motor unit

a single motor neuron and the skeletal muscle fibres that it innervates and so controls, all of which must respond, virtually simultaneously, to an action potential in the nerve axon. The number of muscle fibres in a single motor unit ranges from about 10 to 2000: fewest in small muscles where the control is finest (e.g. for eye and finger movements) and most in large muscles (e.g. quads) designed for force rather than precision. See also muscle, neuromuscular junction.

motor unit

A-alpha (Aα) motor nerve fibre and the muscle fibres it innervates

motor unit

A group of muscle fibres that respond to a stimulus from a single motor neuron. In the extraocular muscles a motor unit consists of less than a dozen small fibres, that is considered to be a small unit. It produces a finer degree of neural control over contraction than a larger unit, which produces more powerful gross movements when activated. See neuron.

mo·tor u·nit

(mō'tŏr yū'nit)
A single somatic motor neuron and the group of muscle fibers innervated by it.

motor

1. pertaining to motion.
2. a muscle, nerve or center that effects movements.

motor activity
limb movement the most obvious of these forms of activity.
motor alpha-neuron
ventral spinal cord neurons which innervate skeletal muscle. Called also final common pathway, lower motor neuron.
motor depressant anticonvulsant
a drug that depresses motor activity and hence prevents convulsions, e.g. phenobarbital sodium, phenytoin sodium.
motor dysfunction
abnormality of the motor system.
motor end-plate
sites of neuraptic transmission of acetylcholine from nerve to muscle receptors.
motor fibers
innervate the body effectors.
motor lubricating oil
ingestion may cause lead poisoning.
motor nerve conduction
the transmission of impulses along motor nerves to skeletal muscle.
motor unit
includes the motor neuron, neuromuscular junction, and the myofibrils innervated by the neuron.
motor unit action potential
the electrical activity of voluntary muscle contractions recorded by needle electromyography.
References in periodicals archive ?
These results were interpreted to indicate that progressive recruitment of larger motor units occurs from the onset of the incremental test up to approximately T-vent.
Changes in force and motor unit involvement velocity (MUIV) induced by plyometric training and the method of incomplete eccentric muscle response.
They determined that with greater amplitude of stimulation, more motor units were recruited, as determined by MRI.
However, the EMG of this case showed fibrillation potentials, complex repetitive and myotonic discharges, with motor unit potentials and recruitment pattern abnormalities indicating a myopathic process [14].
Sale and MacDougal suggest that whenever maximum effort is used, the motor unit activation patterns will be similar, regardless of the external speed movement.
The lift consists of an upholstered swivel seat with two foldable armrests mounted to a motor unit.
in addition, tempo running mimics the pattern of muscle motor unit recruitment during actual competition.
Travel trailers do not have their own motor but are designed to be towed by a motor unit, such as an automobile or a light truck.
Tenders invited for Diaphragm type reciprocating pump motor unit along with pulsation dampener & safety relief valve
2005) reported that an increase in muscle force in participants with the GA genotype, compared with those with the GG genotype, was associated with a more effective force per motor unit size mobilization.
Features include a new air motor unit, based on the supplier's motor-brake, that incorporates an integrated brake system with a stepped brake piston and self-lubricating rotor.

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