(n.) An organic base, especially one of a class of substances occurring ready formed in the tissues of plants and the bodies of animals.
Example Sentences:
(1) Thus, alkaloid and insecticide modifications share many features but differ in how much the conducting properties of the pore are changed and whether the channel can close reversibly while the toxin remains bound.
(2) A clear structure-mutagenicity relationship was observed in a series of aporphine alkaloids (aporphine, dehydroaporphine, 7-oxoaporphine and 4,5-dioxoaporphine), and 10,11-non-substituted aporphines were suggested to exert their mutagenicity through metabolic activation of the 10,11 positions, possibly as the 10,11-epoxides.
(3) A radioactive, photoactive Vinca alkaloid, N-(p-azido-[3,5-3H]-benzoyl)-N'-beta-aminoethylvindesine [( 3H]NABV) with pharmacological and biological activities similar to vinblastine was synthesized and used to identify specific Vinca alkaloid macromolecular interactions in calf brain homogenate by photoaffinity labeling.
(4) The comparative metabolism of the pyrrolizidine alkaloid (PA) senecionine was studied in vitro in incubations of rat, guinea pig, cow, horse, and sheep hepatic microsomes.
(5) They also displayed negative correlation between activities of protein-inhibitors and the total content of protein and alkaloids.
(6) Methods have been reviewed for alkylating agents, platinum compounds, antitumour antibiotics, antimetabolites, alkaloids, suramin, 1-hydroxy-3-amino-propylidene-1,1-bisphosphonate and tamoxifen.
(7) The resistant strains exhibited cross resistance to anthracycline antibiotics, vinca alkaloids, actinomycin D, colchicine.
(8) In mice treated with cepharanthine (Cepha), a biscoclaurine alkaloid, the number of T cells was increased in the parathymic lymph nodes (PtLNs) which are considered to be the specialized lymph nodes in local differentiation of T cells.
(9) The alkaloid tubulosine inhibits the process of peptide chain elongation by eukaryotic polysomes by specifically preventing the elongation-factor-2-dependent step of translocation.
(10) Cultured roots of Stephania cepharantha, which are rich sources of bisbenzylisoquinoline alkaloids, were fed 14C-labelled tyrosine, tyramine or dopamine.
(11) As a possible mechanism underlying the alterations of DRP, the functional consequences of atrophic changes of primary central afferent terminals are being discussed in terms of the close correlation between structure and function and the possible inferences of the electrophysiological reaction to the therapeutic application of Vinca alkaloids in the iontophoretic treatment of chronic intractable pain.
(12) The poisonous principles in tansy ragwort are pyrrolizidine alkaloids, which cause gradual alteration and necrosis of liver cells with replacement by fibrous tissue.
(13) In this study, the roots of Tabernaemontana heyneana Wall were examined and the isolation and identification of additional indole alkaloids and some pharmacological properties of coronaridine are described.
(14) The area ratios of four alkaloids (tropacocaine, norcocaine, cis-cinnamoylcocaine, and trans-cinnamoylcocaine) to cocaine are calculated for each sample.
(15) The main drugs with specific action on migraine include ergot alkaloids (ergotamine, dihydroergotamine), agonists (sumatriptan) or partial agonists (methysergide) at a specific subtype of 5-HT1-like receptors, beta-adrenoceptor antagonists (propranolol, metoprolol), calcium antagonists (flunarizine) and anti-inflammatory agents (indomethacin).
(16) Effects of solution variables on the binding and self-association explain the wide variation of reported apparent binding constants for Vinca alkaloids to tubulin.
(17) The concomitance of five previously reported trans-2,5-dialkyl-pyrrolidines along with small amounts of the cis isomers and N-methyl analogues makes the venom of M. indicum the most qualitatively diverse blend of alkaloids reported from an ant to date.
(18) Strong enhancement of delayed-type hypersensitivity (DTH) was observed after treatment with the active cyclophosphamide (CY) derivative Z 7557 or the plant alkaloid VP-16 at the site of sensitization.
(19) A total alkaloid and two purified alkaloid extracts of Alangium Vitiense were revealed by our experimental screening to be oncostatic on L1210 leukemia and two other lymphoid neoplasias in Mice.
(20) Possible mechanisms underlying these effects of insecticides on alkaloid-dependent uptake are discussed in light of a qualitative model formulated from these results and previous biochemical and electrophysiological studies.
Atropine
Definition:
(n.) A poisonous, white, crystallizable alkaloid, extracted from the Atropa belladonna, or deadly nightshade, and the Datura Stramonium, or thorn apple. It is remarkable for its power in dilating the pupil of the eye. Called also daturine.
Example Sentences:
(1) Comparison if single injections of MSB and atropine in normal subjects also demonstrated a more reliable dose-response relationship with MSB.
(2) ), but it was potentiated by either atropine (5 mg kg-1 i.p.)
(3) Eight healthy, nonsmoking subjects received 1.7, 3.4, and 5.2 mg of atropine sulfate by inhalation and 1.67 mg of atropine free base (equivalent to 2 mg of atropine sulfate) by intramuscular (i.m.)
(4) Anti-histamine and anti-serotonin drugs, as well as substances capable of blocking synthesis of prostaglandins or activation of the kinin system, and also atropine, were ineffective in reducing the responses to TsTX or electrical stimuli.
(5) Neither atropine (1.4 X 10(-6) M) nor propranolol (3.4 X 10(-6) M) blocked the inhibitory action of neurotensin (10(-8) M) on the inhibitory potential.
(6) The effect was countered by prior administration of atropine into the site.
(7) The effects were atropine-resistant and qualitatively similar to those seen with cocaine.
(8) Atropine (1 microM) was used to block the muscarinic cholinoceptors.
(9) The vagally induced pyloric contraction was resistant to atropine but sensitive to SPA and hexamethonium, indicating involvement of SP in the activation of preganglionic neurons as well.
(10) Carbachol microinjected into the LRN also produced an antinociception which was attenuated significantly by atropine but not naloxone previously microinjected into the same site in the LRN.
(11) However, when parasympathetic activity was abolished by atropine and tracheal tone was restored with 5-hydroxytryptamine, benzodiazepines applied on the VMS had no effect on tracheal pressure.
(12) The inhibitory response was not decreased by treatment with atropine, hexamethonium, yohimbine or naloxone, suggesting that muscarinic, nicotinic, alpha 2 adrenergic or opiate receptors were not being stimulated.
(13) The inhibitory phase was blocked by atropine and the excitatory phase was eliminated by tubocurarine chloride, hexamethonium bromide or pindolol.
(14) Acetylcholine increases their turnover, Atropine reduces it, and the addition of atropine counteracts the effect of acetylcholine in all these phospholipids.
(15) Hypoxic exposure following atropine treatment resulted in progressive increases in PVA, Q and stroke volume; fH decreased during the recovery period.
(16) In LM strips, the contractile responses to tachykinins were unaffected by spantide and methysergide, but partly decreased by tetrodotoxin and atropine.
(17) Atropine significantly reduced rhinorrhea, the levels of histamine, and TAME-esterase activity as well as the osmolality of recovered lavage fluids, but had no effect on nasal congestion or albumin.
(18) Combined propranolol-atropine blockade increased heart rate at rest in the SAP state, and significantly attenuated the tachycardia accompanying treadmill exercise.
(19) Atropine inhibited insulin release induced by both acetylcholine and by 16.4 mM glucose.
(20) Atropine stimulated significantly the rat liver and esophagus carcinogenesis, whereas the alpha-adrenoblocking agent, a pyrrhoxane analogue, and, particularly, proserine inhibited these processes.