gold (Au) (gōld) a chemical element, at. no. 79; gold compounds (all of which are poisonous) are used in medicine, chiefly in treating arthritis.
gold (Au)
gold,
gold 198 a radioisotope of gold with a half-life of 2.69 days; it has been used as an intracavitary and interstitial antineoplastic and as a scintiscanning agent.
cohesive gold chemically pure gold that forms a solid mass when properly condensed into a tooth cavity.
gold sodium thiomalate a monovalent gold salt used in treatment of rheumatoid arthritis.
gold (g ld)n. Symbol Au A soft yellow element that resists corrosion and is the most malleable and ductile metal, used to treat rheumatoid arthritis and intravenously in liver imaging. Atomic number 79. |
gold (Au)
Etymology: AS, geolu, yellow
a yellowish soft metallic element that occurs naturally as a free metal and as the telluride AuAgTe4. Its atomic number is 79; its atomic mass is 196.97. Gold has been highly valued since antiquity and has been and is used for currency, for ornamentation, and as a dental restorative material. It is usually hardened by alloying it with small amounts of nickel or copper. It is highly resistive to oxidation but can be dissolved in aqua regia and aqueous potassium cyanide. Gold salts, in which gold is attached to sulfur, are often used in the treatment, or chrysotherapy, of patients with rheumatoid arthritis but cause serious toxicity in about 10% of patients and some toxicity in 25% to 50%. See also chrysotherapy.
gold,
n a precious or noble metal; yellow, malleable, ductible, nonrusting; much used in dentistry in pure and alloyed forms.
)
Exophthalmic goiter.
gold alloys,
n.pl an alloy that contains gold; usually alloyed with copper, silver, platinum, palladium, and zinc. The alloying of gold enhances certain properties such as hardness, or creates a lower melting point for gold solder.
gold, cohesive,
n gold usually manufactured in thin sheets of foil, that has been treated to cause it to cohere, or stick together. This allows it to be easily formed into a variety of shapes.
gold compound,
n a drug containing gold salts, usually administered with other drugs in the treatment of rheumatoid arthritis. Various radioisotopes of gold have been used in diagnostic radiology and in the radiologic treatment of certain malignant neoplastic diseases.
gold, crystal,
n See gold, mat.
gold, fibrous,
n See foil, gold.
gold file,
n See file, gold.
gold foil,
n See foil, gold.
gold foil cylinder,
n See foil cylinder.
gold foil pellet,
n See pellet, foil.
n 1. an alloy, principally gold, used for cast restorations. Desired physical properties may be obtained by selecting those with varying ingredients and/or proportions. Acceptable alloys are classified by the American Dental Association (ADA) specifications according to Brinell hardness: Type A soft, Brinell 40 to 75; Type B medium, Brinell 70 to 100; Type C hard, Brinell 90 to 140.
n 2. an intracoronal cast restoration of gold alloy fabricated outside the oral cavity and cemented into the prepared cavity.
n 2. an intracoronal cast restoration of gold alloy fabricated outside the oral cavity and cemented into the prepared cavity.
gold knife,
n See knife, gold.
gold, mat,
n (crystal gold, sponge gold) a noncohesive form of pure gold prepared by electrodeposition. Sometimes used in the base of restorations and then veneered or overlaid with cohesive foil.
gold, powdered,
n the fine granules of pure gold, formed by atomizing the molten metal or by chemical precipitation. For clinical use, powdered gold is available either as clusters of the granules or as pellets of the powder contained in an envelope of gold foil.
gold saw,
n See saw, gold.
gold sodium thiosulfate,
n an antirheumatic used in the treatment of rheumatoid arthritis.
gold, sponge,
n See gold, mat.
gold, white,
n a gold alloy with a high palladium content. It has a higher fusion range, lower ductility, and greater hardness than a yellow gold alloy.
gold
a chemical element, atomic number 79, atomic weight 196.967, symbol Au. See Table 6. Gold and many of its compounds are used in human medicine and occasionally in veterinary medicine. See also chrysotherapy.
gold-198
a radioisotope of gold having a half-life of 2.7 days and emitting gamma and beta radiation. Symbol 198Au.
gold colloid scintiscan
see scintiscan.
gold dust
a disease of aquarium fish caused by the flagellate protozoon Oodinium limnecicum. Affected fish develop a varnished look caused by a very heavy infestation of the protozoa on the skin and die within a few days.
gold standard
the ultimate standard to which all endeavors aspire.
How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content.
| ?Page tools | ||
|---|---|---|
|