(1) Apparently, the irradiation with visible light of a low intensity creates an additional proton gradient and thus stimulates a new replication and division cycle in the population of cells whose membranes do not have delta pH necessary for the initiation of these processes.
(2) Plasma membranes were isolated from rat kidney and their transport properties for sodium, calcium, protons, phosphate, glucose, lactate, and phenylalanine were investigated.
(3) Hydrogen isotope effects on these mutants indicate that MotA catalyzes proton transfer.
(4) It was concluded that the detachment of the oxaloyl residue from oxaloacetate and its replacement by a proton proceed with inversion of configuration at the methylene group which becomes methyl during the hydrolysis.
(5) There was also a significant increase in the mitochondrial proton conductance pathway of brown adipose tissue, assessed from the binding of guanosine diphosphate (GDP) to mitochondria isolated from the interscapular (89% above control) and perirenal and para-aortic depots (130%).
(6) We propose that, for a GC base pair in B conformation, there are two amino proton exchangeable states--a cytosine amino proton exchangeable state and a guanine amino proton exchangeable state; both require the disruption of only the corresponding interbase H bond.
(7) The rhodamine 123-induced growth inhibition was partially reversed by treating the dye-pre-exposed infected erythrocytes with the proton ionophore carbonyl-cyanide m-chlorophenylhydrazone, which dissipates transmembrane proton gradients.
(8) The detergent lauryl maltoside abolishes respiratory control and proton ejection by cytochrome c oxidase-containing proteoliposomes over a narrow concentration range.
(9) These data are discussed in relationship to the chemical mechanism of GSSG reduction and the identity of the proton-transfer step whose rate is sensitive to solvent isotopic composition.
(10) The chromophore of octopus rhodopsin is 11-cis retinal, linked via a protonated Schiff base to the protein backbone.
(11) Some additional amino proton resonances have also been assigned.
(12) Binding to HSA occurs primarily with the imidazolidine and thiazolidine groups of levamisole as it has been demonstrated by selective changes in the relaxation times and the chemical shifts of the protons attached to the carbon atoms.
(13) Diffusional anisotropy of water protons, induced by nonrandom, directional barriers which hinder or retard water motion, is measurable by MRI.
(14) The present studies examined the effect of cytosolic protons on electrotonic spread and conduction velocity in cardiac Purkinje fibers.
(15) The Pr(III)-induced shifts for several resolved nonexchangeable backbone proton resonances were compared with calculated shifts using the known x-ray structure.
(16) The present analysis concentrates on the utilization of low-energy proton accelerators of several hundred kilovolts for particle-induced X-ray emission microanalysis.
(17) The amount of protons released is in excess with respect to the amount of ubiquinol oxidized.
(18) The ATPase inhibitor dicyclohexylcarbodiimide, which collapsed the chemical and electrical components of the proton motive force, caused rapid cell swelling in the presence of glucose (and high intracellular ATP levels).
(19) In a direct test of the hypothesis that the M2 coat protein of influenza A can function as a proton translocator, we incorporated a synthetic peptide containing its putative transmembrane domain into voltage-clamped planar lipid bilayers.
(20) The pH dependence of this spectral change gave a sigmoidal curve fitted well to a theoretical curve of a cooperative release of two protons with a pK value of 7.5, indicating the existence of the acidic and alkaline forms of the ferrous CO enzyme.
Tritium
Definition:
Example Sentences:
(1) Biliary and urinary excretion of five tritium-labelled cardiac glycosides, i.e.
(2) Tritium-labeled ribonucleic acid precursors, including cytidine, uridine, and orotic acid, were injected into rats with dated pregnancies (14 to 21 days) and virgin rats.
(3) Ovarian aromatase activity, assessed by incubating the homogenised ovaries of treated rats with tritium-labelled androstenedione (0.2 microM) or testosterone (1 microM), indicated that residual enzyme activity was reduced compared with controls.
(4) The adenylate cyclase activator forskolin as well as 8-bromo-cyclic AMP enhanced the electrically evoked release of 3H-noradrenaline and 3H-5-hydroxytryptamine from superfused rat neocortical slices and that of 3H-dopamine from neostriatal slices with comparable EC50's of about 0.5 and 50 microM, respectively, without affecting spontaneous tritium efflux.
(5) It was also found that tritium release also occurred, although to a lesser extent, when tissues were fixed in glutaraldehyde or osmium tetroxide using collidine as a buffer, and this release was not significant when collidine was applied to previously fixed tissues.
(6) The standardised mortality ratios were 889 (six deaths) in employees monitored for contamination by tritium, 254 (nine deaths) in those monitored for contamination by other radionuclides, and 385 (nine deaths) in those with dosimeter readings totalling more than 50 mSv (5 rem); but the same nine subjects tended to account for each of these significantly raised ratios.
(7) 3T3 cells were also used for the incorporation of tritium-thymidine.
(8) Isolated hepatocytes carry out the N-demethylation of dansylamide at near linear rates for up to 8 h. This reaction was measured by following the release of tritium into water on hydroxylation of 3H-labeled methyl groups.
(9) Similar low deuterium and tritium isotope effects were measured with a purified rat liver cytochrome P-450 preparation and horseradish peroxidase.
(10) The effects of alpha-adrenoceptor agonists and antagonists on the electrically (slices) or potassium-evoked (synaptosomes) tritium overflow were studied.
(11) During the monodirectional conversion of D-[2-3H]mannose 6-phosphate to D-fructose 6-phosphate and D-fructose 1,6-bisphosphate, the reaction velocity is one order of magnitude lower than with D-[U-14C]mannose 6-phosphate and little tritium (less than 6%) is transferred intramolecularly.
(12) The 72-hour cumulative urinary excretion of total tritium was 28.2% of the administered dose and only 38.3% of this resided in unchanged HHT.
(13) However, higher doses of diltiazem (60 microM) reduced the tritium overflow elicited by RNS or Vt but enhanced that caused by KCl.
(14) The substrate was labelled by the catalytic addition of tritium to cerebroside sulphate.
(15) In contrast, in synaptosomes superfused with Ca(2+)-free Krebs-Henseleit solution containing 15 mM K+ throughout, ethanol did not affect the tritium overflow evoked by 2 min introduction of 75 microM Ca2+ into the superfusion fluid.
(16) We have assessed a multiwire camera for the high speed, quantitative autoradiography of tritium-labelled substances in two-dimensional systems.
(17) Dipyridamole (5 x 10(-5) M) and erythro-9-2-hydroxy-3 nonyl adenosine (EHNA) (10(-4) M) also reduced tritium release.
(18) Tritium thymidine incorporation rates inform about DNA-synthesis.
(19) GR43175 (1 x 10(-8) to 1 x 10(-5) M) inhibited the electrically evoked release of tritium from renal noradrenergic nerves but did not affect the basal (non-stimulated) release of tritium or perfusion pressure.
(20) The activity of aromatase in microsomal preparations was assayed by determining the rate of incorporation of tritium from 1-[3H]androstenedione into [3H]water.