(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.
Polyacid
Definition:
(a.) Capable of neutralizing, or of combining with, several molecules of a monobasic acid; having more than one hydrogen atom capable of being replaced by acid radicals; -- said of certain bases; as, calcium hydrate and glycerin are polyacid bases.
Example Sentences:
(1) A polyacidic amino acid stretch immediately adjacent to the SRF homologous domain of MCM1 was found to be important for activation of alpha-specific genes in alpha cells.
(2) It was found that high adsorption levels were achieved under conditions of high chain entanglement, such as in a concentrated solution of a polyacid of high RMM.
(3) The C-terminal region of the protein contains the established pattern of polyacidic clusters, common to calreticulins of other species and ends in the ER retention signal HDEL.
(4) We show that this polyacidic sequence appends to RAD6 protein as a polyanionic tail and that its function in vivo does not require stoichiometry of length.
(5) For example, our analysis has identified a conserved polyacidic stretch in all three phosphoproteins which we propose mediates metal binding.
(6) The 24-h DTS values of the HEMA composites (14-26 MPa) were higher than those of the polyacid cements (7-12 MPa).
(7) Strains with deletions of all but the first 4 or 15 residues of the polyacidic sequence were phenotypically almost wild type or wild type, respectively.
(8) We conclude that the intrinsic activity of RAD6 protein resides in the globular domain, that the polyacidic sequence has a stimulatory or modifying role evident primarily in sporulation, and that only a short section apparently functions as effectively as the entire polyacidic sequence.
(9) The various dyes displayed considerable variability in the ease with which they could be displaced from substrates with polyacid solutions during the differentiation step.
(10) Glass-ionomer cements are the reaction product of an aluminosilicate glass and a polyacid, for example poly (acrylic acid).
(11) The N-terminal region, of approximately neutral net charge and hydrophobicity, is followed by a central proline-rich zone with repeat sequences separated from the polyacidic C-terminal stretch by a short hydrophobic sequence.
(12) The subcellular localization and physicochemical properties of prothymosin alpha suggest that its function is related to those of other long polyacidic regions containing nuclear proteins.
(13) Removal of the entire polyacidic sequence severely reduced sporulation but only slightly affected survival after UV irradiation or UV-induced mutagenesis.
(14) Flexural strength was also found to be increased by increasing the molecular weight of the polyacid.
(15) Interactions of proteins with neutral polysaccharides and such polyacids as polygalacturonic acid, chondroitin sulphate, RNA and DNA in a two-phase system composed of phenol and aqueous buffers in the pH range 1.5-10 were studied.
(16) We conclude that this tyrosine kinase is reversibly bound to the membrane through electrostatic interactions with the polyacidic sequence surrounding the phosphate accepting tyrosine 8 on band 3.
(17) Pf16 is highly basic, contains a polyacidic domain consisting of aspartic acid and is related to the non-histone high mobility group proteins of higher eukaryotes.
(18) The carboxyl-terminal polyacidic sequence was sensitive to proteinase K, and it endowed RAD6 protein with an aberrantly large Stokes radius that indicates an asymmetric shape.
(19) Our experiments show that deletion of varying lengths of the polyacidic tail of RAD6 protein greatly reduces its ubiquitin-conjugating activity.
(20) The polyacids, on the other hand, in the absence of interactions were recovered mainly from the aqueous phases.