(a.) Sour, sharp, or biting to the taste; tart; having the taste of vinegar: as, acid fruits or liquors. Also fig.: Sour-tempered.
(a.) Of or pertaining to an acid; as, acid reaction.
(n.) A sour substance.
(n.) One of a class of compounds, generally but not always distinguished by their sour taste, solubility in water, and reddening of vegetable blue or violet colors. They are also characterized by the power of destroying the distinctive properties of alkalies or bases, combining with them to form salts, at the same time losing their own peculiar properties. They all contain hydrogen, united with a more negative element or radical, either alone, or more generally with oxygen, and take their names from this negative element or radical. Those which contain no oxygen are sometimes called hydracids in distinction from the others which are called oxygen acids or oxacids.
Example Sentences:
(1) The amino acid sequence deduced from the nucleotide sequence contained both amino- and carboxyl-terminal sequences.
(2) F(420) is photolabile aerobically in neutral and basic solutions, whereas the acid-stable chromophore is not photolabile under these conditions.
(3) The high amino acid levels in the cells suggest that these cells act as inter-organ transporters and reservoirs of amino acids, they have a different role in their handling and metabolism from those of mammals.
(4) If ascorbic acid was omitted from the culture medium, the extensive new connective tissue matrix was not produced.
(5) The interaction of the antibody with both the bacterial and the tissue derived polysialic acids suggests that the conformational epitope critical for the interaction is formed by both classes of compounds.
(6) Arachidic acid was without effect, while linoleic acid and linolenic acid were (on a concentration basis) at least 5-times less active than arachidonic acid.
(7) An unsaturated fatty acid auxotroph of Escherichia coli was grown with a series of cis-octadecenoate isomers in which the location of the double bond varied from positions 3 to 17.
(8) The ability of azelastine to influence antigen-induced contractile responses (Schultz-Dale phenomenon) in isolated tracheal segments of the guinea-pig was investigated and compared with selected antiallergic drugs and inhibitors of arachidonic acid metabolism.
(9) After 4 to 6 hours of recirculation, accumulation of vasoactive amine, 5-hydroxytryptamine, its major metabolite, 5-hydroxyindole acetic acid, and its precursor amino acid, tryptophan were detected.
(10) Spectrophotometric determination of the sulfhydryl content in the animal tissue before (control) and after using 6,6'-Dithiodinicotinic acid is applied.
(11) This death is also dependent on the presence of chloride and is prevented with the non-selective EAA antagonist, kynurenic acid, but is not prevented by QA.
(12) However, four of ten young adult outer arm (relatively sun-exposed) and one of ten young adult inner arm (relatively sun-protected) fibroblasts lines increased their saturation density in response to retinoic acid.
(13) Microionophoretically applied excitatory amino acids induced firing of extracellularly recorded single units in a tissue slice preparation of the mouse cochlear nucleus, and the similarly applied antagonist 2-amino-5-phosphonovalerate (2APV) was demonstrated to be a selective N-methyl-D-aspartate (NMDA) receptor antagonist.
(14) The LD50 of the following metal-binding chelating drugs, EDTA, diethylenetriaminepentaacetic acid (DTPA), hydroxyethylenediaminetriacetic acid (HEDTA), cyclohexanediaminotetraacetic acid (CDTA) and triethylenetetraminehexaacetic acid (TTHA) was evaluated in terms of mortality in rats after intraperitoneal administration and was found to be in the order: CDTA greater than EDTA greater than DTPA greater than TTHA greater than HEDTA.
(15) Estimations of the degree of incorporation of 14C from the radioactive labeled carbohydrate into the glycerol and fatty acid moieties were carried out.
(16) The second amino acid residue influences not only the rate of reaction but also the extent of formation of the product of the Amadori rearrangement, the ketoamine.
(17) Leumorphin is a 29-amino-acid peptide derived from preproenkephalin B. Intracerebroventricular (i.c.v.)
(18) Hepatic lymph flow increased only after ethacrynic acid and mannitol administration.
(19) The subcellular distribution of sialyltransferase and its product of action, sialic acid, was investigated in the undifferentiated cells of the rat intestinal crypts and compared with the pattern observed in the differentiated cells present in the surface epithelium.
(20) A phytochemical investigation of an ethanolic extract of the whole plant of Echites hirsuta (Apocynaceae) resulted in the isolation and identification of the flavonoids naringenin, aromadendrin (dihydrokaempferol), and kaempferol; the coumarin fraxetin; the triterpene ursolic acid; and the sterol glycoside sitosteryl glucoside.
Alkali
Definition:
(n.) Soda ash; caustic soda, caustic potash, etc.
(n.) One of a class of caustic bases, such as soda, potash, ammonia, and lithia, whose distinguishing peculiarities are solubility in alcohol and water, uniting with oils and fats to form soap, neutralizing and forming salts with acids, turning to brown several vegetable yellows, and changing reddened litmus to blue.
Example Sentences:
(1) Significant amounts of 35S-labeled material were lost during the alkali treatment.
(2) The results also suggest that both alkali metals most probably have been delivered to the suckling pups and some of their toxic effect was retarded.
(3) Rabbits eating Rabbit Chow excreted a very alkaline urine, but rats eating the same diet excreted much less alkali when expressed per kilogram of body weight.
(4) From these findings it is concluded that cardiac performance and carbohydrate metabolism are accelerated in alkali and depressed in acid perfusion, and that myocardial metabolism could be affected by pH not only secondary to the change of performance but also by itself.
(5) Electrophoresis, Sephadex chromatography, and ultrafiltration studies showed that the alkali-soluble, water-soluble cell wall antigen is comprised of lipid, polysaccharide, and protein and has a molecular weight range of 30,000 to 50,000.
(6) [Na+],[Cl-)and[alkali]were determined in the alkaline gastric juice samples (pH greater than 7.0).
(7) Plants placed in pure acid and alkali solutions were also able to neutralize the medium.
(8) TFP produced a more discrete block in the repair of alkali-labile lesions in DNA.
(9) Activation of GV by monochromatic 450-nm radiation causes two specific DNA changes in human P3 cells in culture as shown by alkaline elution techniques: single-strand breaks (i.e., alkali-labile sites plus frank strand scissions) and DNA-to-protein covalent bond crosslinks.
(10) Keratan sulphate was isolated from bovine intervertebral disc and bovine nasal septum after hydrolysis with proteinases and treatment with dilute alkali.
(11) It was necessary to avoid CsCl banding of procapsids in their preparation as this treatment altered both their pI and their sensitivity to alkali dissociation into 14S subunits.
(12) In these muscles, two kinds of mRNA for the cardiac myosin alkali light chain, identical with those in ventricular muscle, were expressed and their relative amount in each tissue was almost the same as that in ventricular muscle.
(13) The enzymes were detected and characterized by agarose gel electrophoresis of alkali-denatured digestion products.
(14) The alkali cations selectivity sequence induced by ETH1811 is Li+ (1) greater than Na+ (0.08) greater than K+ (0.02) greater than Cs+ (0.008).
(15) When the monomer was further dissociated into constituent subunits in strong alkali or at high concentrations of SDS, the CD spectrum disappeared almost completely, indicating loss of the asymmetric interactions of the chromophoric heme a with its immediate environments, consisting of the subunit assembly.
(16) Addition of alkali to the culture media results in decrease of cell GAD activity, whereas increase of enzyme level occurs only in cells growing in unbuffered media.
(17) Chain breaks as measured in alkali were also measured and found to be enhanced by the dye; the ratio of breaks per iodine loss was 0.9.
(18) Alkali hydrolysates of elastins contained a radioactive peak that was eluted between proline and leucine.
(19) Under limiting concentration conditions, BLM and NCS induce alkali-labile sites in DNA without a subsequent cleavage of the chain.
(20) Hydrolysis with mild alkali yields anhydroretinol, as it does for synthetic retinyl phosphate, with absorption maxima at 388, 368, and 346 nm.