(n.) A colorless, tasteless, odorless, gaseous element occurring in the free state in the atmosphere, of which it forms about 23 per cent by weight and about 21 per cent by volume, being slightly heavier than nitrogen. Symbol O. Atomic weight 15.96.
(n.) Chlorine used in bleaching.
Example Sentences:
(1) Steady-state values of cell, glucose, and cellulase concentration oxygen tension, and outlet gas oxygen partial pressure were recorded.
(2) It is concluded that amlodipine reduces myocardial ischemic injury by mechanism(s) that may involve a reduction in myocardial oxygen demand as well as by positively influencing transmembrane Ca2+ fluxes during ischemia and reperfusion.
(3) Heart rate (HR), pulmonary ventilation (V), oxygen consumption (VO2), carbon dioxide production (VCO2), and respiratory quotient (RQ) were measured.
(4) Manometric studies with resting cells obtained by growth on each of these sulfur sources yielded net oxygen uptake for all substrates except sulfite and dithionate.
(5) The data indicate that ebselen is likely to be useful in the therapy of inflammatory conditions in which reactive oxygen species, such as peroxides, play an aetiological role.
(6) These membrane perturbation effects not observed with bleomycin-iron in the presence of a hydroxyl radical scavenger, dimethyl thiourea, or a chelating agent, desferrioxamine, were correlated with the ability of the complex to generate highly reactive oxygen species.
(7) Microelectrodes were used to measure the oxygen tension (PO2) profile within individual spheroids at different stages of growth.
(8) However, time in greater than 21% oxygen was significantly longer in infants less than 1000 g (median 30 days, 8.5 days in patients greater than 1000 g, p less than 0.01).
(9) Previous studies have not evaluated the potential for oxygen toxicity at 9.5 psia.
(10) The pH of ST solutions varied with the mode of oxygenation as follows: 7.9-8.2 in Groups I and IV; 8.7-8.9 in Groups II and V; 7.1-7.4 in Groups III and VI.
(11) The aim of this study was to plot the course of the transcutaneously measured PCO2 (tcPCO2) in the fetus during oxygenation of the mother.
(12) Blood gas variables produced from a computed in vivo oxygen dissociation curve, PaeO2, P95 and C(a-x)O2, were introduced in the University Hospital of Wales in 1986.
(13) Also for bronchogenic carcinoma with that a dependence could be shown between haemoglobin concentration--and by this the oxygen supply of the tumor--and the reaction of the primary tumor after radiotherapy.
(14) The present results using approximately 12% hemoglobin concentration in 0.1 M Bistris buffer at pD 7 and 27 degrees C with and without organic phosphate show that there is no significant line broadening on oxygenation (from 0 to 50% saturation) to affect the determination of the intensities or areas of these resonances.
(15) There was good agreement between the survival of normally oxygenated cells in culture and bright cells from tumors and between hypoxic cells in culture and dim cells from tumors over a radiation dosage range of 2-5 Gray.
(16) In presence of oxygen (air) the phototactic reaction values are somewhat lower than in its absence.
(17) A fiberoptic flow-directed catheter inserted into the hepatic vein continuously measures hepatic venous oxygen hemoglobin saturation (ShvO2).
(18) Anaesthesia was achieved by a mixture of oxygen, nitrous oxide and fluothane without use of muscle relaxants.
(19) The use of 100% oxygen to calculate intrapulmonary shunting in patients on PEEP is misleading in both physiological and methodological terms.
(20) Tachycardia, pulmonary hypertension, increased venous oxygen desaturation, and increasing core temperature develop as the syndrome progresses.
Superoxide
Definition:
(n.) See Peroxide.
Example Sentences:
(1) Preincubation of human neutrophils with recombinant tumor necrosis factor alpha has previously been shown by us to enhance superoxide production of neutrophils in response to the chemotactic peptide formyl-methionyl-leucyl-phenylalanine, and the phorbol ester, phorbol myristate acetate.
(2) Cell viability, ability to generate superoxide anion, and chemotaxis were found to be unaltered both before and after labeling.
(3) Superoxide dismutase (SOD) activity and its concentration were measured in thyroid tissues obtained from patients with Graves' disease, Hashimoto's thyroiditis, differentiated thyroid cancer, and endemic goiter (before and after iodine supplementation) as well as in normal thyroid tissue (paranodular tissue) from patients with follicular adenomas.
(4) Superoxide anion (O2.-) was photogenerated upon illumination of riboflavin in fluorescent light.
(5) The stimulation of superoxide generation by DBS was also inactivated by dodecylamine (DA) but was restored by the subsequent addition of DBS.
(6) Depletion of extracellular Ca2+ by EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N'N'-tetraacetic acid] attenuated both [Ca2+]i increase and superoxide production induced by particles.
(7) At hypothyroid patients there is an ADP excess which is degenerated to xanthine, the substrate of xanthine oxidase resulting in toxic anion superoxide and UA.
(8) This work undertakes the study of changes in urinary, plasmatic and tissue levels of Thromboxane B2 (TXB2) as well as in tissue Prostaglandin E2 (PGE2) after pancreas transplantation and the effect of superoxide dismutase (SOD) on these changes.
(9) After 6 weeks irradiation, the insoluble collagen and elastin were both substantially elevated, as were the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD).
(10) This localization of superoxide in EAU is further evidence of the generation of oxygen reactive species in uveal inflammation.
(11) The erythrocytes of subjects with moderate and severe alcoholic liver cirrhosis had an unbalanced antioxidant system (normal superoxide dismutase, low catalase and glutathione peroxidase activities, and low glutathione content).
(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) The reduction of cytochrome c was found to be sensitive to both anaerobiosis and superoxide dismutase, suggesting the involvement of superoxide anions with this electron acceptor.
(14) The former proved to be a weak superoxide radical generating compound being partially sensitive to the ionic strength.
(15) However, two observations suggested that surface epithelial loss alone was not sufficient to trigger the proliferative response to DOC: intracolonic instillation of DOC followed by removal of the DOC solution at 1 h, at which time surface epithelial loss was maximal, did not result in an increase in ornithine decarboxylase activity or [3H]dThd incorporation into DNA when these parameters were assessed at 4 h or 12 to 48 h, respectively; phenidone, an antioxidant and radical scavenger, and bis[(3,5-diisopropyl-salicylato) (O,O) copper(II), a lipophilic agent with superoxide dismutase activity, abolished the DOC mediated proliferative response but did not prevent the early loss of surface cells.
(16) An automated enzymatic method is described for the determination of Cu,Zn-superoxide dismutase (SOD) in plasma or erythrocytes using the xanthine-xanthine oxidase and cytochrome C coupled assay.
(17) Here we report that phenol hydroxylation to hydroquinone is also catalyzed by human myeloperoxidase in the presence of a superoxide anion radical generating system, hypoxanthine and xanthine oxidase.
(18) Antioxidant status was assessed by measurement of blood glutathione peroxidase, glucose-6-phosphate dehydrogenase, and superoxide dismutase activities and plasma concentrations of vitamin E. Significant differences in these values were not apparent between halothane-reacting pigs and nonreactors.
(19) Indomethacin or superoxide dismutase plus catalase prevented dilation by 5,6-EET and AA, indicating that both produce dilation via cyclooxygenase-dependent oxygen radicals.
(20) The structure of Mn(III) superoxide dismutase (Mn(III)SOD) from Thermus thermophilus, a tetramer of chains 203 residues in length, has been refined by restrained least-squares methods.