colloid


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Related to colloid: Colloid Chemistry, colloid solution

colloid

 [kol´oid]
1. gluelike.
2. the translucent, yellowish, gelatinous substance resulting from colloid degeneration.
3. a chemical system composed of a continuous medium (the continuous phase) throughout which are distributed small particles, 1 to 1000 nm in size (the disperse phase), which do not settle out under the influence of gravity. Colloidal particles are not capable of passing through a semipermeable membrane, as in dialysis. Solutes that can pass through a semipermeable membrane are sometimes called crystalloids. adj., adj colloid´al.
dispersion colloid colloid (def. 3), particularly an unstable colloid system.
emulsion colloid lyophilic colloid
rarely, emulsion.
lyophilic colloid a stable colloid system in which the disperse phase is relatively liquid, usually comprising highly complex organic substances, such as glue or starch, which readily absorb solvent, swell, and distribute uniformly through the continuous phase.
lyophobic colloid an unstable colloid system in which the disperse phase particles tend to repel liquids, are easily precipitated, and cannot be redispersed with additional solvent.
stannous sulfur colloid a sulfur colloid containing stannous ions; complexed with technetium 99m it is used as a diagnostic aid (bone, liver, and spleen imaging).
suspension colloid lyophobic colloid.

col·loid

(kol'oyd),
1. Aggregates of atoms or molecules in a finely divided state (submicroscopic), dispersed in a gaseous, liquid, or solid medium, and resisting sedimentation, diffusion, and filtration, thus differing from precipitates.
See also: hydrocolloid.
2. Gluelike.
3. A translucent, yellowish, homogeneous material of the consistency of glue, less fluid than mucoid or mucinoid, found in the cells and tissues in a state of colloid degeneration. Synonym(s): colloidin
4. The stored secretion within follicles of the thyroid gland. For individual colloids not listed below, see the specific name.
[G. kolla, glue, + eidos, appearance]

colloid

(kŏl′oid′)
n.
1. Chemistry
a. A system in which finely divided particles, which are approximately 1 to 1,000 millimicrons in size, are dispersed within a continuous medium in a manner that prevents them from being filtered easily or settled rapidly.
b. The particulate matter so dispersed.
2. The gelatinous stored secretion of the thyroid gland, consisting mainly of thyroglobulin.
3. Gelatinous material resulting from degeneration in diseased tissue.
adj.
Of, relating to, containing, or having the nature of a colloid.

col·loi′dal (kə-loid′l, kŏ-) adj.
col·loi′dal·ly adv.

colloid

Chemistry
A liquid containing 1.0 mm to 1.0 nm microscopic and submicroscopic particles.

Physiology
The thyroglobulin-rich, homogeneous pale pink (by H&E stain) liquid which is secreted into the follicles by the thyroid cells

col·loid

(kol'oyd)
1. Aggregates of atoms or molecules in a finely divided state (submicroscopic), dispersed in a gaseous, liquid, or solid medium, and resisting sedimentation, diffusion, and filtration, thus differing from precipitates.
See also: hydrocolloid
2. Gluelike.
3. A translucent, yellowish, homogeneous material of the consistency of glue, less fluid than mucoid or mucinoid, found in the cells and tissues in a state of colloid degeneration.
Synonym(s): colloidin.
4. The stored secretion within follicles of the thyroid gland.
[G. kolla, glue, + eidos, appearance]

colloid

A substance in which particles are in suspension in a fluid medium. The particles are too small to settle by gravity or to be readily filtered. The colloid state lies between that of a solution and that of an emulsion.

colloid

a mixture of two substances which are immiscible (see MISCIBLE), but where the particles of one are too small to settle out, and so remain suspended indefinitely. Glue is a colloid of animal gelatin in water; the water is defined as the matrix and the gelatin as the inclusion. Colloid particles measure 1 x 10-4 to 1 x 10-6 mm in diameter, forming either a SOL or GEL structure which does not diffuse through cell membranes. Colloids are common in cells, where their large surfaces are important for chemical changes constantly in progress there.

col·loid

(kol'oyd)
Aggregates of atoms or molecules in a finely divided state, dispersed in a gaseous, liquid, or solid medium, and resisting sedimentation, diffusion, and filtration, thus differing from precipitates.
[G. kolla, glue, + eidos, appearance]
References in periodicals archive ?
We reviewed 160 (80 for colloid preloading and 80 for crystalloid co-loading) consecutive medical records in each study period cohort that met the inclusion criteria.
For example, administration of early fluid therapy in sepsis improves survival17, conservative vs liberal fluid therapy in patients with acute lung injury reduces the days of mechanical ventilation17 and synthetic colloids cause acute kidney injury18.
In colloid goitre there is biosynthetic defect and iodine deficiency with reduced thyroid hormone synthesis and secondary increase in TSH level with thyroid enlargement.
Surgical treatment of colloid cysts includes three techniques: stereotactic aspiration, endoscopic fenestration, and a microsurgical approach, the latter two are used most frequently.
If one considers the threshold value of stability at [+ or -] 25 mV, it can be stated that the as-synthesized gold colloid possesses a good electrostatic repulsion driven stability [5].
Large-duct type cysts usually represent as several small cysts, while neoplastic mucin cysts, colloid carcinomas, and degenerative necrotic cysts usually present as a single cyst.
Caption: Figure 7: Normalized transmittance for a sample of stock colloid as a function of the power of the pump beam.
It is also reported that the rates of complete removal of cyst using endoscopic methods are improving, which may be due to the learning curve associated with new technology, as well as technological advances such as the use of tubular retractors and endoscopes with multiple working channels.1-3,5 Robot-controlled endoscopy may be another promising avenue.6 Endoscopic resection has also been supported as a preferred treatment option for asymptomatic, incidental colloid cysts.4,8 More recently, an antero-lateral endoscopic approach with dual instrument technique, has been reported with good results.9 Each technique has its own set of strengths, limitations and possible complications; results are dependent on the complexity of the case and familiarity of the surgeon to the procedure.
It was found in Figure 7 that the system density was very close to the true density of colloid. At this moment, the system reached a balance again, and then there was a NPT balance lasting for 500 ps at 0.09 GPa.
Colloid cysts are benign tumors of brain that rise from endodermal embryologic remnants and are classically located on the roof of the third ventricle [1,2].
offered a nonneuroepithelial origin of colloid cyst, indicating its similarity to respiratory mucosa of the trachea and sphenoid sinus by using immunohistochemical techniques [7].
An extraordinary aspect of this case is that the CT scans revealed a colloid cyst at the center of his brain, a congenital condition which he had all his life but did not know.