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...[继续阅读]

    See acetylcholine.参阅acetylcholine。...[继续阅读]

    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....[继续阅读]

    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...[继续阅读]

    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...[继续阅读]

    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.当溶质分子溶解在溶剂中达解离平衡时,进入溶剂分子的氢原子。例如...[继续阅读]

    See staining.参阅staining。...[继续阅读]

    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.中和给定1g脂肪中游离脂肪酸所需要的氢氧化钾的毫克数,酸值被用来度量脂肪中的游离酸。...[继续阅读]

    SeeAIDS.参阅AIDS。...[继续阅读]

    An aromatic heterocyclic com-pound found in coal tar. It is the parent com-pound of a number of effective mutagens.煤焦油中的芳香族杂环化合物。是许多有效诱变剂的母体化合物。...[继续阅读]