(a.) Having the same percentage composition; -- said of two or more different substances which contain the same ingredients in the same proportions by weight, often used with with. Specif.: (a) Polymeric; i. e., having the same elements united in the same proportion by weight, but with different molecular weights; as, acetylene and benzine are isomeric (polymeric) with each other in this sense. See Polymeric. (b) Metameric; i. e., having the same elements united in the same proportions by weight, and with the same molecular weight, but which a different structure or arrangement of the ultimate parts; as, ethyl alcohol and methyl ether are isomeric (metameric) with each other in this sense. See Metameric.
Example Sentences:
(1) Structure assignment of the isomeric immonium ions 5 and 6, generated via FAB from N-isobutyl glycine and N-methyl valine, can be achieved by their collision induced dissociation characteristics.
(2) This is interpreted to mean that the release of fructose from the central complex is faster than the isomerization of the E-NADH complex.
(3) The optical and oxygen binding properties of the reconstituted myoglobins containing two isomeric monoformyl-monovinylhemins were found to be different.
(4) Line broadening detected in several of the high-field nuclear magnetic resonance spectra was attributed to cis-trans isomerization.
(5) Two new isomeric delta-lactones 2 and 3 have been isolated from the marine fungus Helicascus kanaloanus (ATCC 18591).
(6) Two isomeric hydrolysis products of this compound with only three 3(R)-hydroxymyristic acid moieties attached to the disaccharide-1-phosphate were also identified.
(7) Studies on the metabolism of nicotine by rabbit liver microsomal fractions in the presence of 0.01 M sodium cyanide have led to the characterization of two isomeric cyanonicotine compounds.
(8) Kinetic methods are outlined for the distinction between two pathways of substrate binding, which include an isomerization either of the free enzyme or of the enzyme-substrate complex.
(9) In the case of H101S, a mutant protein with measurable isomerizing activity, substrate binding with novel fluorescent properties was observed, possibly the bound pyranose form of xylose under steady-state conditions.
(10) There were consistent isomeric preferences for the R(-) configuration of both DA analogs in stimulating adenylate cyclase (D-1 sites) and in competing for high affinity binding of 3H-spiroperidol (D-2 sites) and of 3H-ADTN (DA agonist binding sites) in striatal tissue, with lesser isomeric differences in the limbic tissue.
(11) Oligosaccharides 3 and 4 and oligosaccharides 5 and 6 were isolated as unresolved isomeric mixtures in fractions B3a and B4a, respectively.
(12) Subsequent fractionation of the original compound into its two isomeric forms resulted in the identification of the isomer primarily responsible for this convulsive activity.
(13) However, the 1500 K simulation produced higher energy structures, even after minimization; in addition, this highest temperature run had many cis-trans peptide isomerizations.
(14) From model compound data, it is shown that the expected rate for isomerism is in satisfactory agreement with the rates actually observed for protein folding.
(15) Re-analysis of PCP and PCP-Na samples with high PCDD contents on a high-resolution glass capillary column showed the presence of 3 hexa- and the 2 heptachlorodibenzo-p-dioxins with nearly constant isomeric ratios.
(16) Such a genomic structure does not appear to have been reported amongst the herpesviruses--all the genomes that do not isomerize either have repeat structures only at the termini, or if present internally, have only direct repeats.
(17) The isomeric N,N-dimethyl-4,5-diphenyl-1H-pyrazole-1-propanamine was completely inactive in the primary antidepressant screens.
(18) Correspondingly, in the case of the histidine-peptides examined only mixtures of the cyclic isomeric compounds were isolated and structurally characterized by 1H-NMR analysis.
(19) In contrast to the biphasic unfolding of the wild-type nuclease, the unfolding of the mutant is represented by a single-phase reaction, indicating that the biphasic unfolding for the wild-type protein is caused by cis-trans isomerization about the prolyl peptide bond in the native state.
(20) In order to prepare a completely light-stable rhodopsin, we have synthesized an analog, II, of 11-cis retinal in which isomerization at the C11-C12 cis-double bond is blocked by formation of a cyclohexene ring from the C10 to C13-methyl.
Pentene
Definition:
(n.) Same as Amylene.
Example Sentences:
(1) When treated with the carbonyl reagent 2,4-dinitrophenylhydrazine, the reactive fractions yielded derivatives, some of which were identified by mass spectrometry as hydrazones of nonenal, heptenal, pentenal, and crotonaldehyde.
(2) The lipophilic neutral complex [99mTc][TcO(MRP20)] [MRP20 is (N-(2(1H pyrolylmethyl]N'-(4-pentene-3-one-2)ethane-1,2-diamine)] is known to cross the blood-brain barrier in non-primate animals.
(3) The latex of (Euphorbia esula) has been found to contain highly skin irritant and inflammatory ingenol-3delta 2,4,6,8,10 pentene tetradecanoate and another factor, ingenol-3-dodecanoate, which is less irritating but which can be responsible for the cocarcinogenic activity exhibited by the latex preparation in the mice back skin experiment.
(4) However, P-450SG1 showed no lanosterol 14 alpha-demethylase activity and its mode of interaction with diniconazole [(E)-1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-y1)-1- penten-3- o1], a specific inhibitor of P-450(14DM), was fundamentally different from that of P-450(14DM).
(5) Highly purified exonuclease I isolated from an over-producing stain contains high levels of dRpase activity; it catalyzes the release of deoxyribose-5-phosphate from an AP site incised with endonuclease IV of E. coli and the release of 4-hydroxy-2-pentenal-5-phosphate from an AP site incised by the AP lyase activity of endonuclease III of E. coli.
(6) The volatile fragments of air-aged cholesterol were analysed by means of gas chromatography-mass spectrometry; The following fourteen compounds were identified: ethanol, acetic acid, acetone, 2-methylpropene, 2-methyl-1-propanol, 2-methyl-2-propanol, 2-butanone, 2-methylpropionic acid, 2-methyl-2-butanol, 2-pentanone, 3-methyl-2-butanone, 2-methyl-1-pentene, 2-methyl-2-pentanol, and 2-methyl-4-penten-2-ol.
(7) 1-p-Chlorophenyl-4,4-dimethyl-5-diethylamino-1-penten-3-one hydrobromide (CDDP) has been shown to react selectively with small molecular weight and protein thiols.
(8) Six components, whose concentrations were depressed after adrenalectomy, were identified: 2-heptanone, trans-5-hepten-2-one, trans-4-hepten-2-one, n-pentyl acetate, cis-2-penten-1-yl acetate, and 2,5-dimethylpyrazine.
(9) Long-chain enals are very toxic to TA104, but addition of a reduced glutathione chase following an incubation period decreases this toxicity, thus enabling the detection of 4-hydroxy-pentenal, a homolog of the lipid peroxidation product, 4-hydroxy-nonenal, as a mutagen.
(10) The lactone is preceded in the pathway by 2-amino-2-penten-4-ynoate, a transient electron-rich species which binds tightly to D-amino-acid oxidase and induces a charge-transfer complex with the electron-deficient bound flavin coenzyme.
(11) The major components included acetic and hexanoic acids, trans 3-penten-1-ol, 2-heptanol, 3-methyl-2-buten-1-ol, benzyl alcohol and linalool.
(12) Five cytotoxic Mannich bases (5-dimethylamino-1-substituted phenyl-1-penten-3-ones), three having antineoplastic activity, were evaluated for respiratory-inhibiting properties in rat liver mitochondria in the presence of four substrates: succinate, glutamate, 3-hydroxybutyrate, and palmitylcarnitine.
(13) Malealdehyde (MLA) and 4-hydroxy-2,3-trans-penten-1-al (4-HPE) inhibit rat liver glucose-6-phosphatase activity in vitro.
(14) citral, ethly crotonate, mesityl oxide, acrylic acid) or form very labile adducts (crotonal, pentenal, hexenal, 3-methyl-butenone).
(15) All other compounds tested gave 1 crosslink per plasmid molecule in the mM concentration range as follows: acetaldehyde, 115 mM; propionaldehyde, 295 mM; butyraldehyde, 360 mM; crotonaldehyde, 8.5 mM; trans-2-pentenal, 6.3 mM.
(16) This 7-(2-oxopropyl)-substituted 1,N2-ethenodeoxyguanosine adduct was formed by reaction of 4-oxo-2-pentenal (3-acetylacrolein) with the 1 and N2 positions of deoxyguanosine.
(17) The beta-alkyl substituted acrolein congeners crotonaldehyde, trans-2-pentenal, trans-2-hexenal, 2,4-hexadienal, and trans-2-heptenal were clearly mutagenic in a slightly modified preincubation Ames test with Salmonella typhimurium TA100 with and without S9 mix using a threefold bacterial cell density and a 90-min preincubation time, whereas trans-cis-2,6-nonadienal did not show any mutagenic activity.
(18) Major products formed in incubations of alpha-acetoxyNPIP for 7-24 h in phosphate buffer (pH 7.0) at 37 degrees C included 4-oxo-2-pentenal (11-21% yield), 4-hydroxypentanal (18-22%), and 5-hydroxypentanal (27-29%).
(19) Histrionicotoxin is (2pR, 6S, 7pS, 8aS)-7-(cis-1-buten-3-ynyl)-8-hydroxy-2-(cis-2-penten-4- ynyl)-1-azaspiro[5.5] undecane, while in dihydro-isohistrionicotoxin the acetylenic 2-pentenynyl side chain is replaced by an allenic 2-(3,4 pentadienyl) substituent.
(20) The Km for the removal of trans-4-hydroxy-2-pentenal 5-phosphate is 0.06 microM; the Km for the removal of 2-deoxyribose 5-phosphate is 0.17 microM.