(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.
Thiophene
Definition:
(n.) A sulphur hydrocarbon, C4H4S, analogous to furfuran and benzene, and acting as the base of a large number of substances which closely resemble the corresponding aromatic derivatives.
Example Sentences:
(1) Quantitative structure activity relationships of 2-amino-3-carboxylic acid ethyl ester thiophene derivatives are described.
(2) Some of the thiophenes and their acetylenic derivatives possess extremely potent phototoxic activities toward membrane-containing viruses.
(3) The compounds were obtained by condensation of appropriate hydrazines with thiophene 2-carboxaldehyde (series 1), thiophene 3-carboxaldehyde (series 2), and 5-nitrothiophene-2-carboxaldehyde (series 3).
(4) The prototype kappa-selective agonist, PD117302 (trans-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]benzo[b]thiophene-4- acetamide, 2) has been regio- and stereoselectively substituted in the C-4 and C-5 positions of the cyclohexyl ring with the methyl ether and spiro tetrahydrofuran groups.
(5) Since no previously identified genes involved in thiophene metabolism are located in this region, we designated the gene for the 48-kDa protein as thdF.
(6) Among the compounds described are 6-hydroxybenzo[b]thiophene-2-sulfonamide (16) and its acetate ester (23), which are among the most potent ocular hypotensive agents in this class, as assessed in the alpha-chymotrypsinized rabbit.
(7) The normalizing effects of the thiophene compounds on serum phosphorus levels were not significant at the dosages used.
(8) Maximum photo-basophil-histamine-release was 4% with acetylsalicylic acid, 10% with benoxaprofen, 20% with thiophene, 28% with diclofenac, 39% with tiaprofenic acid, 40% with carprofen, 55% with ketoprofen, and not demonstrable with indoprofen.
(9) The more hydrophobic cephalosporins, with a thiophene moiety at the C7 position, were more active than C7-methoxyiminoaminothiazole derivatives against S. aureus H (beta-lactam-susceptible), and compounds with a thioether function at C3 were more active than those with a sulphonyl function at this position.
(10) Several guanidine compounds were synthesized by the reaction of acid chlorides of thiophene and furan with guanidines.
(11) Alpha-terthienyl (alpha-T), a phototoxic thiophene compound isolated from marigolds (Tagetes species), affects cell membranes and does not appear to induce cytogenetic damage.
(12) In a directed search for the best compounds for clinical evaluation, some 150 selected nitroaromatic compounds, representing 6 distinct types, namely, furans, thiophenes, imidazoles, pyrazoles, pyrroles, and triazoles, have been synthesized and tested as hypoxic cell radiosensitisers and bioreductive drugs.
(13) Replacement of ring A by heterocyclic rings (thiophene or pyridine) leads to analogues with only moderate activity.
(14) These results clearly show that all three thiophene systems have potent activity as antihypertensive agents and that 3 and 4 are more potent than 1 or 2 as alpha 1-antagonists in vivo.
(15) A comparative study of the intestinal transport of DL-tryptophan and its 1-methylindole (tryptophan-l-Me) and benzo[b]thiophene (tryptophan-S) analogs has been carried out in vitro, using the everted intestinal sac of the rat and hamster.
(16) Except for cardioselectivity at low doses, the thiophenic analogue of metoprolol behaves in a very similar way as this compound in all the aspects considered in a preliminary pharmacological study.
(17) Six-month chronic oral toxicity studies of 7-chloro-3-[1-(2, 4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethoxy-methyl] benzo[b]thiophene (sertaconazole, FI-7045, CAS 99592-32-2) were carried out in rats and ferrets.
(18) N-(3-dimethylaminopropyl)naphtho[2,1-b]thiophene-4-carboxamide and the 6-substituted methoxy, methyl, fluoro, chloro, bromo, trifluoromethyl, and cyano derivatives have been shown to bind to DNA via intercalation with binding constants in the 35-900 X 10(3) range at 25 degrees C, pH 7, and [Na+] = 0.019M.
(19) Tienilic acid (TA) is metabolized by human liver microsomes in the presence of NADPH with the major formation of 5-hydroxytienilic acid (5-OHTA) which is derived from the hydroxylation of the thiophene ring of TA.
(20) The synthesis of 1-substituted benzothieno[2,3-d]imidazoles and their most suitable synthesis precursor 2-nitro-3-substituted-amino benzo[b]thiophenes is reported.