pA2是一种用以表示竞争性拮抗剂作用强度的指标，其意义是能使激动剂提高到原来的2倍时，可产生与原来浓度相同效应所需的拮抗剂的摩尔浓度（克分子浓度现已很少用）的负对数(-log(B))。

2017年4月24日 · In the field of biochemistry, a pA2 value determines the important relationship between two drugs "competing" for effect on the same receptor. The "agonist" drug tries to affect the receptor. The "antagonist" drug attempts to block the agonist from working.

2022年11月16日 · The effects of most drugs depend on the dose that is provided to the subject. In line with this, we have a concept called “dose descriptors”, which takes into account the relationship between a particular dose of a drug and the corresponding effect...

2016年1月20日 · 可用拮抗参数(pA2)表示竞争性拮抗药的作用强度，其含义为：当激动药与拮抗药合用时，若2倍浓度激动药所产生的效应恰好等于未加入拮抗药时激动药所引起的效应，则所加入拮抗药的摩尔浓度的负对数值为pA2。

索莫吉效应（Somogyi effect）为凌晨3时低血糖、早餐前高血糖的现象，是胰岛素使用过量致夜间低血糖反应后，升糖激素反馈性地分泌增加，出现的血糖反跳性升高现象，呈“低后高”的特征。

The pA2 value is the negative logarithm of the molar concentration of antagonist which causes a twofold shift of the concentration-response curve for agonist. The larger the pA2 the more potent the antagonist. where pAx is the negative log of the concentration of antagonist used and x is the concentration-ratio.

The pA2 is a measure of the affinity of a competitive antagonist for its receptor. The determination of the pA2 is made from experiments in which a fixed concentration of the antagonist is used along with graded concentrations of an agonist acting on the same receptor.

1981年1月1日 · The analgesic effect of a subcutaneous injection of morphine was assessed by the tail-flick method as an increase in the reaction time of the animal (tail flick) to avoid a painful stimulus. A reaction time of 1.61 0.02 seconds (mean SE) was recorded in the vehicle- …

2024年11月29日 · pA2值是用于描述竞争性拮抗剂对药物效果抑制程度的一个参数。它代表了在保持药物效果不变的情况下，所需增加的拮抗剂浓度的负对数。pA2值越高，说明拮抗剂的作用越强，即需要更少的拮抗剂就能显著降低药物的效果。

2023年4月29日 · pA2是一种用以表示竞争性拮抗剂作用强度的指标，其意义是能使激动剂提高到原来的2倍时，可产生与原来浓度相同效应所需的拮抗剂的摩尔浓度（克分子浓度现已很少用））的负对数。