antagonist


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antagonist

1. any muscle that opposes the action of another
2. a drug that counteracts the effects of another drug

antagonist

[an′tag·ə‚nist]
(biochemistry)
A molecule that bears sufficient structural similarity to a second molecule to compete with that molecule for binding sites on a third molecule.
(pharmacology)
A drug or other chemical substance capable of reducing the physiological activity of another chemical substance; refers especially to a drug that opposes the action of a drug or other chemical substance on the nervous system by combining with and blocking the nerve receptor.
(physiology)
A muscle that contracts with, and limits the action of, another muscle, called an agonist, with which it is paired.
References in periodicals archive ?
Its advantage over GnRH analogues are absence of the first flare-up effect, reduced risk of oestrogen deficiency syndrome, sufficient LH blockage in a short duration of time, dose-dependent effect, fast withdrawal from antagonist effects, reduced treatment duration and the total dose of gonadotropin and a low risk of high order multiple pregnancies when standard strict criteria are applied for cycle cancellation.
The filing of the NDA for CINVANTI is an important milestone, bringing us one step closer to a new NK1 receptor antagonist treatment option for cancer patients suffering from the debilitating side effects of chemotherapy, said Kimberly J.
LISBON -- Women undergoing assisted reproduction had similar pregnancy rates with gonado-tropin-releasing hormone agonist and antagonist protocols, but less ovarian hyperstimulation syndrome with the GnRH-antagonist protocol in a large randomized trial.
Meanwhile, some studies support earlier initiation of GnRH antagonists based on the observations that the exposure to LH and estradiol in the early follicular phase of a GnRH antagonist cycle was negatively associated with the probability of pregnancy (10, 11).
M2 EQUITYBITES-November 10, 2014-Heron Therapeutics reveals development program for a P/neurokinin-1 receptor antagonist
M2 PHARMA-November 10, 2014-Heron Therapeutics reveals development program for a P/neurokinin-1 receptor antagonist
This study wasn't designed to determine why the results contradicted the "impressive benefits of aldosterone antagonist therapy" reported in "pivotal" effica cy trials as well as in a systematic review of randomized clinical trials of the therapy.
This study wasn't designed to determine why the results contradicted the "impressive benefits of aldosterone antagonist therapy" reported in "pivotal" efficacy trials as well as in a systematic review of randomized clinical trials of the therapy.
However, the TNF antagonist RCTs, similar to other biologic RCTs for the treatment of RA, routinely apply stringent inclusion and exclusion criteria that weaken the generalizability of RCT results to the majority of RA patients.
Aloxi is a selective 5-HT3-receptor antagonist, developed for the prevention of CINV, with a long half-life of 40 hours and at least 30 times higher receptor binding affinity than currently available compounds.
The kids range in age from seven to ten, and they can identify a book's protagonist and antagonist, characterize its setting, isolate the climax, and dig out underlying themes.
1988), demonstrated that brevetoxin-induced contractile effects can be blocked with atropine but not with a histamine antagonist, suggesting that toxin-induced constriction results from stimulation of parasympathetic postganglionic neurons.