tonicity


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Related to tonicity: hypertonic, osmotic pressure

tonicity

 [to-nis´ĭ-te]
the state of tissue tone or tension; in body fluid physiology, the effective osmotic pressure equivalent.

to·nic·i·ty

(tō-nis'i-tē),
1. A state of normal tension of the tissues by virtue of which the parts are kept in shape, alert, and ready to function in response to a suitable stimulus. In the case of muscle, it refers to a state of continuous activity or tension beyond that related to the physical properties; that is, it is active resistance to stretch; in skeletal muscle it is dependent upon the efferent innervation.
See also: isotonicity. Synonym(s): tonus
2. The osmotic pressure or tension of a solution, usually relative to that of blood.
See also: isotonicity.
[G. tonos, tone]

tonicity

/to·nic·i·ty/ (to-nis´ĭ-te) the state of tissue tone or tension; in body fluid physiology, the effective osmotic pressure equivalent.

tonicity

(tō-nĭs′ĭ-tē)
n. pl. tonici·ties
1. Normal firmness or functional readiness in body tissues or organs.
2. The sustained partial contraction of resting or relaxed muscles.

tonicity

[tōnis′itē]
Etymology: Gk, tonikos, stretching
the quality of possessing tone, or tonus.

to·nic·i·ty

(tō-nis'i-tē)
1. A state of normal tension of the tissues by virtue of which the parts are kept in shape, alert, and ready to function in response to a suitable stimulus. In the case of muscle, it refers to a state of continuous activity or tension beyond that related to the physical properties, i.e., its active resistance to stretch; in skeletal muscle, it is dependent on the efferent innervation.
Synonym(s): tonus.
2. The osmotic pressure or tension of a solution, usually relative to that of blood.
See also: isotonicity
[G. tonos, tone]

solution, hypertonic 

A solution with an osmotic pressure greater than that of an isotonic solution. Hypertonic ophthalmic solutions cause some stinging when instilled. Examples: sodium chloride 5%: when applied to an oedematous cornea this solution reduces oedema by drawing water from it; sulfacetamide sodium 30%; glycerol (or glycerin), at a dose of 1-1.5 g/kg body weight given as a solution with water or other liquid, which draws water from the eye into the blood and thereby reduces the intraocular pressure. Syn. hyperosmotic agent. See hyperosmotic agent; osmotic pressure; physiological saline.
hypotonic s. A solution with an osmotic pressure lower than that of an isotonic solution. Hypotonic ophthalmic solutions generally cause less irritation than hypertonic ones. See osmotic pressure.
isotonic s. A solution with an osmotic pressure equal to that on the other side of a semipermeable membrane. Example: sodium chloride 0.9% is considered to be approximately isotonic with the tears. See osmotic pressure; physio-logical saline.

tonicity

the state of tissue tone or tension; in body fluid physiology, the effective osmotic pressure equivalent.
References in periodicals archive ?
The central nervous system (CNS) mechanisms that regulate water rely on osmolarity and tonicity for activation.
4) In a study by Auerbach et al (32), the newborns of mothers who received antipsychotic and anti-anxiety medications during pregnancy exhibited poor neonatal motor functioning, including tremulousness, hyper- tonicity, and poor motor maturity.
Subsequently Di Bella and Estienne in 1990 stated that internal sphincterotomy reduce anal pain by reduction of the sphincter tonicity (7).
It also covers pharmaceutical excipients and packaging, analysis, product characterization, quality control, stability, bioavailability, dissolution, and fundamental science concepts like thermodynamics, ionic solutions and electrolyte equilibria, tonicity, chemical kinetics, rheology, complex formation, and interfacial phenomenon.
Lancome also claimed Genifique can achieve "clinically-measurable" results of youthful skin and can be seen - fine lines, radiance, clarity and evenness - and felt - texture, resiliency, tonicity and firmness.
These properties may explain the lack of pain, spasm and more serious morbidity associated with the intra-arterial injection of less water-soluble, alkaline or high tonicity drugs, which may result in vasoconstriction, crystal formation and subsequent arterial thrombosis (1).
Mrs DuFaur's paper suggested the use of pelvic floor muscle exercises in the antenatal period to maintain the "suppleness and tonicity of the perineum" (p13), although the primary focus was to increase the mother's awareness of how to relax her pelvic floor muscles during labour.
Regulation of cyclooxygenase-2 expression in renal medulla by tonicity in vivo and in vitro.
In comparison to the NAPI normreference, the preterm infants showed less muscular tonicity on the scarf sign, less vigor and spontaneous movement, higher alertness and orientation, weaker cry, and more sleep state.
Acids are commonly used in medicines as buffering agents to maintain chemical stability, improve flavour and to control tonicity.
Pathogenesis of seizures occurring during restoration of plasma tonicity to normal in animals previously chronically hypernatremic.
The intake of meals mixed with such extracts also confers tonicity to the digestive and the circulatory tracts.