(n.) An elementary substance, not metallic in its nature, which is present in all organic compounds. Atomic weight 11.97. Symbol C. it is combustible, and forms the base of lampblack and charcoal, and enters largely into mineral coals. In its pure crystallized state it constitutes the diamond, the hardest of known substances, occuring in monometric crystals like the octahedron, etc. Another modification is graphite, or blacklead, and in this it is soft, and occurs in hexagonal prisms or tables. When united with oxygen it forms carbon dioxide, commonly called carbonic acid, or carbonic oxide, according to the proportions of the oxygen; when united with hydrogen, it forms various compounds called hydrocarbons. Compare Diamond, and Graphite.
Example Sentences:
(1) Carbon dioxide (CO2) levels, volumes, and temperatures of expired gas were measured from the tracheal and esophageal tubes.
(2) Biochemical, immunocytochemical and histochemical methods were used to study the effect of chronic acetazolamide treatment on carbonic anhydrase (CA) isoenzymes in the rat kidney.
(3) To quantify the size of the lesion in mice, the area of the infarct on the brain surface was assessed planimetrically 48 h after MCA occlusion by transcardial perfusion of carbon black.
(4) Ethanol and L-ethionine induce acute steatosis without necrosis, whereas azaserine, carbon tetrachloride, and D-galactosamine are known to produce steatosis with varying degrees of hepatic necrosis.
(5) Heart rate (HR), pulmonary ventilation (V), oxygen consumption (VO2), carbon dioxide production (VCO2), and respiratory quotient (RQ) were measured.
(6) Given Australia’s number one position as the worst carbon emitter per capita among major western nations it seems hardly surprising that islanders from Fiji, Samoa, Vanuatu and other small island developing states have been turning to Australia with growing exasperation demanding the country demonstrate an appropriate response and responsibility.
(7) 4) Parents imagined that fruit drinks, carbonated beverages and beverages with lactic acid promoted tooth decay.
(8) This capacity is expressed during incubation of the bacteria with the substrate and needs a source of carbon and other energy metabolites.
(9) The disappearance of the herbicide, Avadex (40% diallate), from five agricultural soils (differing in either pH, carbon content, or nitrogen content), incubated under sterile and non-sterile conditions, was followed for a period of 20 weeks.
(10) Environment groups Environment groups that have strongly backed low-carbon power have barely wavered in their opposition to nuclear in the last decade, although their arguments now are now much about the cost than the danger it might pose.
(11) Cultured cells from fourth to ninth passage showed positive labelling for S 100 protein, carbonic anydrase (CAA), glutamine synthetase (GS), alpha cristallin (alpha C) and polyclonal glial fibrillary acidic protein (GFAP) antibody, but were negative for both monoclonal GFAP antibody and also for Muller cells in the retina.
(12) They argue that the US, the world's largest producer of greenhouse gases per capita (China recently surpassed us in sheer volume), needs to lead the fight to limit carbon emissions, rather continuing to block global treaties as it has done in the past.
(13) Thin layers of carbon (20 microns) and vacuoles (30 microns) suggested a large temperature gradient along the tissue ablation front.
(14) Aryl hydrocarbon hydroxylase (AHH) inducibility, carbon monoxide in expired air (CO), serum gammaglutamyl-transferase (GGT), and total cholesterol were compared in equal-sized, age-matched samples of healthy middle-aged males born in 1921, 1934-1936, and 1946 attending the ongoing preventive medical population program in Malmö.
(15) The disappearance of ribosomes in Escherichia coli cells starved for a carbon source was studied.
(16) It was shown that the levels of ATP and ADP in the mycelium depended on the carbon source: the maximum and minimum ATP concentrations were found on the glucose and acetate media respectively, the maximum and minimum ADP concentrations showed inverse dependence.
(17) The mechanism by which such high levels were attained was primrily a combination of arterial hypoxia and a high carbon monoxide yield from tobacco.
(18) Nick Robins, head of the Climate Change Centre at HSBC, said: "If you think about low-carbon energy only in terms of carbon, then things look tough [in terms of not using coal].
(19) Immediately prior to and at maximal workloads, carbon monoxide shifted into extravascular spaces and returned to the vascular space within five minutes after exercise stopped.
(20) The purity and configuration of each isomer of the free acid and N-chloroacetylated derivative were ascertained by: (a) paper chromatography in five solvent systems, (b) elemental analysis, (c) Van Slyke nitrous acid determination of alpha-carbonyl carbon, and (d) Van Slyke ninhydrin determination of alpha-carbonyl carbon, and (e) optical rotation.
Piperidine
Definition:
(n.) An oily liquid alkaloid, C5H11N, having a hot, peppery, ammoniacal odor. It is related to pyridine, and is obtained by the decomposition of piperine.
Example Sentences:
(1) The N-nitrosamines studied were, N-nitroso: dimethylamine, diethylamine, dipropylamine, dibutylamine, pyrrolidine, piperidine, morpholine, methylbenzylamine, bis-(2-hydroxypropyl)amine, bis-(2-oxopropyl)amine and 3,4-dichloropyrrolidine.
(2) In addition, we have found that the dissociative anesthetic N-(1-[2-thienyl]cyclohexyl)3,4-piperidine ([3H]TCP) binds to a site whose regional distribution is highly correlated with that of NMDA receptor sites.
(3) Reduced MPTP (piperidine analog) is inactive in the tissue culture model, while fully oxidized MPTP (pyridinium analog) destroys dopamine neurons.
(4) By use of polyacrylamide sequencing gels the formation of piperidine-labile N7-methylguanine adducts from the reaction of 9 and MNU with 5'-32P-end-labeled DNA restriction fragments is reported.
(5) Drugs of the fentanyl series (4-anilino-piperidines) were potent displacers whereas agonists of the delta- (enkephalin derivatives), sigma- (phencyclidine, haloperidol, 3-hydroxyphenyl-propylpiperidine) or K- (U 50488) opiate sites had a low affinity (Ki greater than 0.5 microM) for 3H-lofentanil specific binding sites.
(6) Piperidine, pyrrolidine, 4-hydroxypiperidine and piperazine at concentrations of 1 microM-30 mM completed dose-dependently with [3H]nicotine and [3H]CD for the binding sites.
(7) It is concluded that the minimum structural requirement for inhibition of alpha-L-fucosidase is the correct configuration of the hydroxy groups at the piperidine ring carbon atoms 2, 3 and 4.
(8) Specific binding was prevented by various dopamine uptake blockers, pyrovalerone, GBR 13069, GBR 12783, N-[1-2-benzo(b)thiophenyl)cyclohexyl] piperidine, cocaine, methylphenidate and was inhibited in a stereoselective manner by the enantiomers of nomifensine.
(9) Chain breaks were induced at the crosslinked sites upon piperidine treatment.
(10) By the aid of enzymatic treatment with calf intestinal phosphatase, the 3'-phosphatase activity of T4-polynucleotide kinase, chemical modification with piperidine in addition to the Maxam-Gilbert sequencing procedure, followed by separation on a DNA-sequencing gel, the nature of the cleaved phosphodiester bond, both 3' and 5' to the cleavage site, has been established.
(11) The ability of the muscarinic receptor antagonists fenipramide, 4-diphenylacetoxy-N-methyl piperidine methiodide (4-DAMP) and secoverine to displace [3H]QNB binding was correlated with the inhibition of responses of cholinomimetics at muscarinic receptors in the atria and ileal longitudinal muscle of the guinea-pig.
(12) In competition studies, the pharmacologic profile of [3H]haloperidol-labeled sigma receptors in human PBL was virtually identical with that in rat cerebellum (slope, 0.87; correlation coefficient, 0.96); the rank order of potency of competing drugs was haloperidol greater than l-butaclamol = pentazocine greater than d-3-(hydroxyphenyl)-N-(1-propyl)-piperidine greater than DTG = d-butaclamol = d-SKF 10,047 greater than levallorphan greater than or equal to PCP greater than or equal to l-SKF 10,047 greater than TCP greater than MK-801.
(13) [3H]N-1-(2-Thienyl)cyclohexyl-3,4-piperidine binding to the phencyclidine site associated with the N-methyl-D-aspartate receptor was reduced by 60-80% in all brain regions examined (P less than 0.001).
(14) Subsequent piperidine hydrolysis produced more frequent breaks of the phosphodiester bonds at guanine positions, thus forming alkali-labile sites.
(15) The binding of [3H]TCP (N-[1-(2-thienyl)cyclo-hexyl]-3,4-piperidine) to the NMDA receptor remained unchanged in all the experimental groups tested.
(16) The postulated active conformation for 1-benzyl-4-[(5,6-dimethoxy-1-oxoindan-2-yl)methyl]piperidine hydrochloride (1a), a potent AChE inhibitor, is close to the crystal structures of 1a with respect to the indanone-piperidine substructure, but differs from the crystal structures for the benzylpiperidine moiety.
(17) Piperidine treatment of the irradiated samples led to specific cleavage of the target with the yield up to 40%.
(18) 65, 499-560) by which aqueous piperidine creates strand breaks at sites of N7-guanine alkylations: alkaline conditions catalyze rupture of the C8-N9 bond, forming a formamido-pyrimidine structure which is displaced from the ribose moiety by piperidine.
(19) Our results show that low energy conformers of the 4-phenyl piperidines have equatorial phenyl rings and cannot completely overlap with rigid opiates at the receptor.
(20) It appears that these piperidine derivatives interfere with the coupling mechanism between acetylcholine-receptor binding and ionic conductance increases.