(n.) Any one of several isometric hydrocarbons, C7H16, of the paraffin series (nine are possible, four are known); -- so called because the molecule has seven carbon atoms. Specifically, a colorless liquid, found as a constituent of petroleum, in the tar oil of cannel coal, etc.
Example Sentences:
(1) The transport of two amino acid analogues, alpha-aminoisobutyric acid and 2-aminobicyclo [2,2,1]-heptane-2-carboxylic acid, which differ in their mode of uptake, was also measured following induction by DMSO.
(2) This technique includes extraction, purification using the solvents n-heptane and 0.5 M Na2CO3, and methylation by 0.1 M HCl-methanol.
(3) High concentrations of leucine or its non-metabolizable analogue, 2-aminobicyclo(2,2,1)heptane-2-carboxylic acid (BCH), stimulated insulin release into the culture medium but did not preserve glucose-stimulated insulin release.
(4) Extractions by the Twisselmann method give increasing yields in the order n-pentane, hexane, and n-heptane.
(5) Mobile phases found useful were combinations of 2-propanol and n-heptane.
(6) Consistent with the FDA guidelines in effect at the time of this study, testing was performed with five FSL (water, 3% acetic acid, 8% and 50% ethanol, and n-heptane) at 49 degrees C. Detailed comparisons were made between the migrations to foods and to FSL; following are the more relevant conclusions.
(7) 2-Amino bicyclo-(2,2,1)-heptane-2-carboxylic acid produces a remarkable inhibition of the rate of L-Tyr uptake, but alpha-methylaminoisobutyric acid does not affect the rate of transport of this amino acid.
(8) The addition of the ion-pairing reagent heptane sulfonate was shown to be necessary to achieve separation of all of these bases.
(9) The analysis, in which mercaptopurine and the internal standard, 6-methylthio-2-hydroxypurine, are chromatographed as ion-pairs with heptane-sulfonic acid, employs a simple and rapid sample preparation based on deproteination using 60% trichloroacetic acid.
(10) The recovery of rodent hairs from chocolate has been significantly improved by the introduction of an additional defatting step, substitution of 40% isopropanol for water, and substitution of mineral oil-heptane (85+15) for heptane in the trapping-off step.
(11) This may be attributable to its relatively low partition coefficient (6.1 in n-heptane).
(12) This transport was preferentially inhibited by the system L specific analogue, 2-aminobicyclo[2.2.1]heptane-2-carboxylic acid, the system T substrate tryptophan, and the sulphur homologue of tyrosine, 4-S-cysteinylphenol.
(13) The color reaction which is specific for estrogens is formed by shaking an aliquot of the heptane eluate of mestranol with a 30% methanol-sulfuric acid solution.
(14) 2-[Bicyclo(2,2,1)heptane-2-endo-3-endo-dicarboximido]-glutarimide (taglutimide, K-2004) proved to be a new sedative-hypnotic drug which did not produce any toxic effects when administered orally to mice even at a very high dosage.
(15) Infrared and NMR measurements on solutions of lithium and cesium dinonylnaphtalene sulfonates (DNNS-salts) in heptane show that the state of water in these systems is in several respects similar to its state in solid ion exchange resins and in some respects also similar to that in ordinary water.
(16) Radioligand binding affinities of four new muscarinic antagonists and six potential muscarinic agonists which possess the 2-alkyl-2-azabicyclo[2.2.1]heptane ring system have been determined in rat heart, rat brain, and m1- or m3-transfected CHO cell membrane preparations to examine the selectivity for subtypes of muscarinic receptor.
(17) A simple and convenient chromatographic method is described for the simultaneous and complete separation of the unconjugated steroids progesterone, deoxycorticosterone and 17 alpha-hydroxyprogesterone on 40-cm columns of Sephadex LH-20 using a water-saturated solvent system containing n-heptane-chloroform (1:1) plus 0.25% of ethanol.
(18) alpha Terpineol was recovered from equine tissues by extraction into heptane and detected by gas chromatography, using either flame ionization detection or pentafluoropropionic anhydride derivatization and electron capture detection.
(19) DU-6859, (-)-7-[(7S)-amino-5-azaspiro(2,4)heptan-5-yl]-8-chloro-6- fluoro-1-[(1R,2R)-cis-2-fluoro-1-cyclopropyl]-1,4-dihydro-4-oxoquinol one-3- carboxylic acid, is a new fluoroquinolone with antibacterial activity which is significantly better than those of currently available quinolones.
(20) Stomach and intestine contents and blood samples from guinea-pigs were cleaned up by use of a kieselguhr column followed by heptane-water partition.
Hydrocarbon
Definition:
(n.) A compound containing only hydrogen and carbon, as methane, benzene, etc.; also, by extension, any of their derivatives.
Example Sentences:
(1) The high transition enthalpy for kerasin is ascribed to a lesser accommodation of gauche conformers in the hydrocarbon chains just below the transition temperature.
(2) 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.
(3) The length of the hydrocarbon chains of the surface-modified silica supports had no significant influence on the selectivity.
(4) The specificity of binding to microsomal proteins of metabolically activated hydrocarbons has been studied.
(5) Aryl hydrocarbon (benzo(a)pyrene) hydroxylase is present and inducible in Buffalo rat liver cells in culture.
(6) The possible occupational cause of the disease, as more solvents in the mud have the structure of aromatic hydrocarbons is discussed.
(7) Experiments with a series of adsorbents homologous with CPAD-Sepharose, in which the length of the hydrocarbon chain was varied, provided strong evidence of hydrophobic interactions, in addition to ionic interactions, in the binding of these proteins to CPAD-Sepharose.
(8) In the hydrocarbon promotion study, dose related increases were observed in the incidence of ACF in male rats promoted with UG or 50 ppm TMP for 24 or 60 weeks.
(9) The results also demonstrated that there was not any apparent correlation between the receptor-binding avidities and in vitro monooxygenase enzyme-induction potencies for the most active polynuclear aromatic hydrocarbons.
(10) Both main-stream and side-stream cigarette smoke condensates and some fractions, containing water-soluble bases, water-insoluble bases, and polycyclic aromatic hydrocarbons, were found to induce AHH activity in lung and liver, the lung being induced to the greatest extent.
(11) Pancreas transplantation offers the possibility of preventing the development and progression of diabetic lesions by adequate control of hydrocarbon metabolism.
(12) A comparison of the relative cytosolic Ah (9S) receptor binding affinities and aryl hydrocarbon hydroxylase (AHH) induction potencies of these hydrocarbons with their 4S protein binding affinities demonstrated the following: five compounds, namely 1,2,5,6-dibenz[a]-anthracene, 1,2,3,4-dibenz[a]anthracene, picene, benzo[a]pyrene and 3-methylcholanthrene exhibited high to moderate binding affinities for the 4S and 9S cytosolic proteins (EC50 values less than 10(-6) M) and induced AHH in rat hepatoma cells; three compounds, namely perylene, benzo[e]pyrene and benzo[g,h,i]perylene exhibited high affinities for the 4S binding protein (1.25 X 10(-7), 4.4 X 10(-8) and 2.9 X 10(-8) M, respectively) and low affinities (EC50 values greater than 10(-5) M) for the Ah receptor protein; moreover these three compounds did not induce AHH in rat hepatoma H-4-II E cells in culture.
(13) It was found that HBSAg was strongly bound to straight hydrocarbon chains with more than seven carbon atoms.
(14) The parent hydrocarbons and the related K-region dihydrodiols induced some sister-chromatid exchanges but they were considerably less active than these two non-K-region diols.
(15) The effect of various fuel additives on the ability of platinum-palladium catalytic converters to remove the carbon monoxide and hydrocarbon components of automotive exhaust has been examined.
(16) Other chlorinated hydrocarbons as decachlorobiphenyl, pentachloronaphthalene, hexachloronaphthalene and hexachlorostyrene were identified, but not quantified.
(17) It has been estimated that natural oil seeps may also contribute as much as 10% of the hydrocarbons in the global marine environment.
(18) The metabolic fate of the carcinogenic aza-aromatic hydrocarbon 7-methyl[7-(14)C]benz[c]acridine (14C-7MBAC) was studied in hepatocytes freshly isolated from untreated, phenobarbital-pretreated and 3-methylcholanthrene-pretreated rats.
(19) Renal cytochrome P450, aryl hydrocarbon hydroxylase, 7-ethoxycoumarin-O-deethylase, and benzphetamine N-demethylase were increased after partial hepatectomy by 84%, 360%, 165% and 406%, respectively.
(20) Antioxidants devoid of hydrocarbon tails, are 10-20 fold more potent LPO inhibitors than the corresponding AOs with hydrocarbon tails.