| purine base | A purine. (05 Mar 2000) |
|---|---|
| pyrimidine base | <biochemistry> A family of 6-membered heterocyclic compounds occurring in nature in a wide variety of forms. They are planar and aromatic in character and include several nucleic acid constituents (cytosine, thymine, and uracil) and form the basic structure of the barbiturates. It is the parent compound of the pyrimidine bases of nucleic acid. (21 Jun 2000) |
| shellac base | A resinous wafer adapted to maxillary or mandibular casts to form baseplates. (05 Mar 2000) |
| hydroxy-Y base | <chemical> Chemical name: 1h-imidazo(1,2-a)purine-7-butanoic acid, 4,9-dihydro-beta-hydroxy-alpha-((methoxycarbonyl)amino)-4,6-dimethyl-9-oxo-, methyl ester Synonym: alpha-(carboxyamino)-beta-hydroxy-4,9-dihydro-4,6- dimethyl-9-oxo-1h-imidazo(1,2-a)purine-7-butyric acid dimethyl ester (26 Jun 1999) |
| skull base | The internal and external base of the cranium: respectively the inner and outer surfaces of the inferior region of the skull. The internal base constitutes the floor of the cranial cavity. (12 Dec 1998) |
| skull base neoplasms | Neoplasms of the base of the skull specifically, differentiated from neoplasms of unspecified sites or bones of the skull (skull neoplasms). (12 Dec 1998) |
| negative base excess | A measure of metabolic acidosis, usually predicted from the Siggaard-Andersen nomogram; the amount of strong alkali that would have to be added per unit volume of whole blood to titrate it to pH 7.4 while at 37캜 and at a carbon dioxide pressure of 40 mm Hg. (05 Mar 2000) |
| nitrogenous base | <biochemistry> A nitrogen-containing molecule having the chemical properties of a base. (09 Oct 1997) |
| nucleic acid base | A purine or pyrimidine; found in naturally occurring nucleic acids such as DNA. (05 Mar 2000) |
| nucleinic base | An obsolete term for purine. (05 Mar 2000) |
| denture base | That part of a denture which rests on the oral mucosa and to which teeth are attached, that part of a complete or partial denture which rests upon the basal seat and to which teeth are attached. Synonym: saddle. (05 Mar 2000) |
| dissociation constant of a base | Expressed by the general equation [B+][OH-]/[BOH] = Kb, where BOH is the undissociated base. (05 Mar 2000) |
| internal base of skull | <anatomy> The interior aspect of the skull base on which the brain rests; the floor of the cranial cavity. See: base of skull. Synonym: basis cranii interna. (05 Mar 2000) |
| ointment base | The vehicle into which active ingredients may be incorporated. Petrolatum (which may be stiffened with wax) is the most widely used greasy ointment base and is suitable for the incorporation of oleaginous materials. Lin-containing bases will absorb water (and dissolved materials) and form water-in-oil type emulsions. Water soluble (washable) bases are often derived from polymers of ethylene glycol (PEGS); these will absorb water and ingredients dissolved in the water. Ointment bases are usually pharmacologically inert but may entrap water and serve to keep the skin from dying or to provide an emollient protective film. (05 Mar 2000) |
| temporary base | <cell biology> A hypothetical cell adhesion molecule possibly involved in sponge cell adhesion, existence unproven. (18 Nov 1997) |