(n.) A volatile, very inflammable liquid, C6H6, contained in the naphtha produced by the destructive distillation of coal, from which it is separated by fractional distillation. The name is sometimes applied also to the impure commercial product or benzole, and also, but rarely, to a similar mixed product of petroleum.
Example Sentences:
(1) The low affinity of several N1-alkylpyrroleethylamines suggests that the benzene portion of the alpha-methyltryptamines is necessary for significant affinity.
(2) Essential parameters of hepatic functioning in 84 labourers, whose exposition to benzene is differing in assimilation as well as length of time is discussed.--45 persons from the same county without contact to benzene or hepatotoxic agents served as control-group.
(3) In the liver, the major site of benzene metabolism, benzene is converted by a cytochrome P-450-mediated pathway to phenol, the major metabolite, and the secondary metabolites, hydroquinone and catechol.
(4) The significance of the present findings on the mutual suppression of metabolism between benzene and toluene is discussed in relation to solvent toxicology and biological monitoring of exposure to the solvents.
(5) Service station attendants' exposure to benzene, based on 85 TWA results at 7 stations, were well below 1 ppm except one exposure of 2.08 ppm.
(6) For cases where background contamination could not be adequately controlled, the assay was modified for the quantitative determination of labelled benzenes six mass units heavier than natural benzene (benzene-d6 or benzene-13C6).
(7) We have investigated the whole-body dermal penetration of styrene, xylene, toluene, perchloroethylene, benzene, halothane, hexane, and isoflurane in rats and compared the permeability constants with available human studies on vapor penetration.
(8) Numerical and structural chromosome changes in bone marrow cells have been described in subjects with benzene haemopathy.
(9) On the other hand, Sudan III pretreatment suppressed benzene-induced CA at all periods after the benzene injection.
(10) Benzene is the only chemical agent for which strong evidence of leukaemogenesis exists.
(11) 14C-Methylthio-labelled 2-methylthio-4-ethylamino-6-tert-butylamino-sym-triazine (terbutryn), pentachlorothioanisole (PCTA), and 1,4-bis(methylthio)tetrachloro-benzene (bis-MTTCB) and their methylthio-oxidation congeners were reacted with glutathione (GSH) in the presence and absence of immobilized liver microsomal enzymes.
(12) The drug is extracted from buffered plasma at pH 9.0 with benzen.
(13) Laser photolysis techniques have been used to characterize the reactivity of triplet state lipoidal benzophenone derivatives toward fatty acids and glycerides in benzene solution.
(14) In experiments in vitro, neither benzene, toluene nor xylene changed the number of sister-chromatid exchanges (SCEs) or the number of chromosomal aberrations in human lymphocytes.
(15) The compound is extracted from aqueous solution with benzene and cleaned up by liquid chromatography.
(16) In pursuing the study on pyridodiazepinone derivatives, in order to verify the variation of biological activity induced by replacement of the heteroaromatic with an aromatic nucleus and by the introduction of chlorine on the benzene ring, a series of 1-[(dialkylamino)alkyl]-4-phenyl-1,3-dihydro-2H-1,4-benzodiazepin- 2-ones and of 7-chloro-analogues were prepared.
(17) Benzene toluene, styrene, 1,1,1-trichloroethylene, and tetrachloroethylene are taken as examples of solvents showing various toxicokinetic properties.
(18) DAS protected the anion exchange system not only against inhibition by DNFB but also by m-isothiocyanato benzene sulfonic acid.
(19) The m-xylene-adapted microorganisms in the aquifer column degraded toluene, benzaldehyde, benzoate, m-toluylaldehyde, m-toluate, m-cresol, p-cresol, and p-hydroxybenzoate but were unable to metabolize benzene, naphthalene, methylcyclohexane, and 1,3-dimethylcyclohexane.
(20) Anticonvulsant activity and toxicity of 20 arylsuccinimides were quantitatively correlated with the hydrophobic, electronic and steric parameters of the substituents in the benzene ring and at the nitrogen atom.
Hydrogen
Definition:
(n.) A gaseous element, colorless, tasteless, and odorless, the lightest known substance, being fourteen and a half times lighter than air (hence its use in filling balloons), and over eleven thousand times lighter than water. It is very abundant, being an ingredient of water and of many other substances, especially those of animal or vegetable origin. It may by produced in many ways, but is chiefly obtained by the action of acids (as sulphuric) on metals, as zinc, iron, etc. It is very inflammable, and is an ingredient of coal gas and water gas. It is standard of chemical equivalents or combining weights, and also of valence, being the typical monad. Symbol H. Atomic weight 1.
Example Sentences:
(1) The hypothesis that proteins are critical targets in free radical mediated cytolysis was tested using U937 mononuclear phagocytes as targets and iron together with hydrogen peroxide to generate radicals.
(2) It has been conformed that catalase from bovine liver eliminates only the pro R hydrogen atom from ethanol.
(3) We investigated the possible contribution made by oropharyngeal microfloral fermentation of ingested carbohydrate to the generation of the early, transient exhaled breath hydrogen rise seen after carbohydrate ingestion.
(4) Hydrogen isotope effects on these mutants indicate that MotA catalyzes proton transfer.
(5) Excessive accumulation of hydrogen ions in the brain may play a pivotal role in initiating the necrosis seen in infarction and following hyperglycemic augmentation of ischemic brain damage.
(6) Studies were conducted in isolated, buffer-perfused rat lungs to determine if prostaglandin (PG) E1 attenuated pulmonary edema provoked by hydrogen peroxide (H2O2).
(7) All N and O atoms except N(3) and O(4') participate in a three-dimensional hydrogen-bonding system.
(8) Both adiphenine.HCl and proadifen.HCl form more stable complexes, suggesting that hydrogen bonding to the carbonyl oxygen by the hydroxyl-group on the rim of the CD ring could be an important contributor to the complexation.
(9) Control mutant S38N has stability essentially the same as that of wild-type lysozyme but hydrogen bonding similar to that of the stabilizing mutant S38D.
(10) High intensity ultrasound also enhances the heterogeneous catalysis of alkene hydrogenation by Ni powders.
(11) An atmosphere of hydrogen eliminates this inhibition in the hydrogenase-containing T. foetus but not in E. invadens which lacks the enzyme.
(12) Vanadate-dependent oxidation of either pyridine nucleotide was inhibited by the addition of either superoxide dismutase or catalase, indicating that both superoxide and hydrogen peroxide may be intermediates in the process.
(13) Our findings suggest that (a) the inclusion of a liquid meal provides a reproducible method of measuring orocaecal transit using the lactulose hydrogen breath test, (b) rapid small bowel transit in thyrotoxicosis may be one factor in the diarrhoea which is a feature of the disease and (c) if altered gut transit is the cause of sluggish bowel habit in hypothyroidism, delay in the colon, and not small bowel, is likely to be responsible.
(14) Stepwise hydrogenation of metal tetradehydrocorrin salts (10 double bonds) yields a series of macrocycles containing 9, 8, 7, 6 and 5 double bonds and conditions necessary to obtain corrins have been established.
(15) For dipeptides containing the amino terminal residues glycine, alanine and phenylalanine, abstraction of the hydrogen from the carbon adjacent to the peptide nitrogen was the major process leading to the spin-adducts.
(16) (7) The first-order radical transformation rates are independent of the (initial) concentration of N3 or peptide and unaffected by urea (as a modifier of hydrogen bond structures).
(17) Intermolecular contacts occur in both oligomers in the minor groove: in the B form through twisted guanine-guanine hydrogen bonding, and in the Z form through base-base stacking and the water network.
(18) Equilibrium-partitioning measurements indicate that the relative affinities of different probes for PC-rich vesicles, in competition with HODMA or DOTAP vesicles, increase with increasing hydrogen-bonding capacity of the probe headgroup in the order PC less than N,N-dimethyl PE less than N-methyl PE less than PE approximately phosphatidyl-2-amino-1-propanol.
(19) When tissue metabolism was irreversibly inhibited by exposure to formaldehyde, hydrogen ion concentration and pCO2 were significantly decreased in the mucosal side of the chamber compared with the viable gall bladder.
(20) Based on the refined atomic coordinates of the tRNAphe in the orthorhombic crystal, on the recent advances in the distance dependence of the ring-current magnetic field effects and on the adopted values for the isolated hydrogen-bonded NH resonances, a computed spectrum consisting of 23 protons was constructed.