stain

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stain

a dye or similar reagent, used to colour specimens for microscopic study

Stain (microbiology)

Any colored, organic compound, usually called dye, used to stain tissues, cells, cell components, or cell contents. The dye may be natural or synthetic. The object stained is called the substrate. The small size and transparency of microorganisms make them difficult to see even with the aid of a high-power microscope. Staining facilitates the observation of a substrate by introducing differences in optical density or in light absorption between the substrate and its surround or between different parts of the same substrate. In electron microscopy, and sometimes in light microscopy (as in the silver impregnation technique of staining flagella or capsules), staining is accomplished by depositing on the substrate ultraphotoscopic particles of a metal such as chromium or gold (the so-called shadowing process); or staining is done by treating the substrate with solutions of metallic compounds such as uranyl acetate or phosphotungstic acid. Stains may be classified according to their molecular structure. They may also be classified according to their chemical behavior into acid, basic, neutral, and indifferent. This classification is of more practical value to the biologist. See Medical bacteriology

Stain

A coloring liquid or dye for application to any porous material, most often wood; thinner than paint and readily absorbed by the wood so that the texture and grain of the wood is enhanced, and not concealed.

stain

[stān]
(materials)
A nonprotective coloring matter used on wood surfaces; imparts color without obscuring the wood grains.
Any colored, organic compound used to stain tissues, cells, cell components, cell contents, or other biological substrates for microscopic examination.

stain

1. A discoloration in the surface of wood, plastic, sealant, etc.
2. A colorant for enhancing wood grain during finishing.
References in periodicals archive ?
* Small, circular, red or purplish spots first appear on young leaves, then coalesce into large glossy, dark, irregular blotches.
The isolate, Cg-2 identified to be highly antagonistic against the spot blotch pathogen was cultured on PDA for 15 days in Petri plates and the spore suspension was prepared as described earlier for the spot blotch pathogen and its population was adjusted to 3 X [10.sup.6] spores/mL.
said Monday it has confirmed 1,233 more people in Japan have developed white blotches after using its skin-whitening cosmetics, bringing the total number of sufferers to 15,192.
As you might expect for a depiction of nighttime, blues and greys predominate, but only to set off the blotches of vibrant red, green, yellow and burgundy -- each depicting an individual reveler or clutching couple.
Each blotch is based on some original instance of analog formlessness, which is corrupted by being (mis)treated with a number of digital processes and then subjected to further analog deteriorations in the process of silk-screening.
Dorsal fin with dark brown blotch basally between sixth and ninth spines, continuous with intensified dark brown blotch immediately adjacent to fin base.
walindi from Papua New Guinea and the Solomon Islands, but differs with regards to male colour pattern, particularly the number, shape and position of large dark blotches along the back and adjacent dorsal fin.
Numerous genetic studies have identified major genes and QTLs conferring resistance to spot blotch, NTNB, SSLB, and leaf scald (Williams, 2003).
Of 46 heavily pigmented snakes examined from the TCWC, 58.7% had dorsal body blotch counts below 44.5, compared to 58.1% of intermediate-pigmented snakes, and 100% of light-ventered snakes.
Wunderlich is part of a team of advisors and researchers that has been monitoring and mapping vineyards with a pattern of red blotch spreading.