An impor-tant intermediate in cell metabolism,par-ticularly in the oxidation of sugars,fattyacids,and amino acids,and in certainbiosynthetic pathways. It is formed by the reaction between pyruvate (from GLY-COLYSIS) and COENZYME A,catalyzedby the enzyme p...[繼續(xù)閱讀]

    See acetylcholine.參閱acetylcholine。...[繼續(xù)閱讀]

    A substance that gives rise to hydro-gen ions (or H3O-) when dissolved in wa-ter. An acid in solution will have a pH be-low 7. This definition does not take into ac-count the competitive behavior of acids insolvents and it refers only to aqueous sys-tems....[繼續(xù)閱讀]

    A chemical compound thatproduces an acid when added to water. Forexample,sulfur trioxide is the acid anhydrideof sulfuric acid:SO3+H2O→H2SO4Organic acid anhydrides are derived by re-moving the elements of water (i. e. two hy-drogen atoms and one oxygen) f...[繼續(xù)閱讀]

    Maintenance of theoptimum pH of body fluids by regulatingthe acid:base ratio. This usually involves abuffer system (see buffer). For example,mammalian blood must be maintained at apH of 7.4,which requires a ratio of car-bonic acid to bicarbonate of 1 : 20...[繼續(xù)閱讀]

    A hydrogen atom in a mole-cule that enters into a dissociation equilibriumwhen the molecule is dissolved in a sol-vent. For example,in acetic acid(CH3COOH)the acidic hydrogen is the oneon the carboxyl group,-COOH.當(dāng)溶質(zhì)分子溶解在溶劑中達(dá)解離平衡時(shí),進(jìn)入溶劑分子的氫原子。例如...[繼續(xù)閱讀]

    See staining.參閱staining。...[繼續(xù)閱讀]

    The number ofmilligrams of potassium hydroxide (KOH)required to neutralize the free fatty acids inone gram of a given fat. It is used as ameasure of free acid.中和給定1g脂肪中游離脂肪酸所需要的氫氧化鉀的毫克數(shù),酸值被用來(lái)度量脂肪中的游離酸。...[繼續(xù)閱讀]

    SeeAIDS.參閱AIDS。...[繼續(xù)閱讀]

    An aromatic heterocyclic com-pound found in coal tar. It is the parent com-pound of a number of effective mutagens.煤焦油中的芳香族雜環(huán)化合物。是許多有效誘變劑的母體化合物。...[繼續(xù)閱讀]