(a.) Of or pertaining to selenium; derived from, or containing, selenium; specifically, designating those compounds in which the element has a higher valence as contrasted with selenious compounds.
Example Sentences:
(1) This inhibition was partially reversed on addition of the translocated substrates sulphate or selenate to the external medium: selenite which is not translocated does not protect against DIDS inhibition.
(2) Pregnant hamsters were treated with selenite, selenate, and selenomethionine during the critical stages of embryogenesis.
(3) Since selenate was not reduced by GSH, this reaction proved that ATP sulphurylase had formed an active selenate.
(4) The Food and Drug Administration gave approval in 1974 for the oral administration of supplemental selenium as either sodium selenite or sodium selenate to certain classes of swine and poultry.
(5) The absence of undersulfated chains in preparations from cultures exposed to selenate supports the concept that, in the intact cell, the polymerization of heparan sulfate might be dependent on the sulfation of the saccharide units added to the growing glycosaminoglycan chain.
(6) Selenate reduction was rapid, with turnover rate constants ranging from 0.04 to 1.8 h-1 at total Se concentrations in pore water of 13 to 455 nM.
(7) Three groups of 5 pigs each were fed a high selenium (Se) diet by mixing either Astragalus praelongus (31.6 ppm Se in feed), A bisulcatus (31.7 ppm Se in feed), or sodium selenate (26.6 ppm Se in feed) with commercial hog feed.
(8) However, we showed ATP-, Mg2+- and ATP sulphurylase-dependent, and inorganic pyrophosphatase-stimulated, production of elemental selenium from selenate in the presence of GSH (reduced glutathione).
(9) In the presence of ATP and Mg2+, ATP sulphurylase from Saccharomyces cerevisiae catalysed the conversion of selenate into a compound with the electrophoretic and acid-lability properties of adenosine 5'-sulphatophosphate.
(10) Selenite (Se4+) was more toxic than selenate (Se6+) in the in vitro system, in which embryonic mesenchymal limb bud cells differentiated into chondrocytes, as well as in the blastocyst culture system.
(11) These results probably explain the ability of mammals, lacking a sulphate reductase system, to incorporate selenium from selenate into seleno-amino acids.
(12) Neither selenate nor selenomethionine produced changes in concentrations of intracellular glutathione.
(13) Sodium selenate alone and combined with vitamin E significantly increased the serum selenium levels, but the activity of serum glutathione peroxidase (GSH-Px) increased significantly only in the selenium- and vitamin E-treated patients with low initial GSH-Px activity.
(14) Neither selenate nor molybdate inhibited sulphate-dependent P(i)-ADP exchange and crude spinach extracts did not catalyse selenate-dependent P(i)-ADP exchange.
(15) It is concluded from these results that selenate is transported actively by the ileal mucosa and that a common transport mechanism for selenate and sulfate exists.
(16) Chromatographic parameters were optimized to determine selenate (SeO4(2-)) by single-column ion chromatography with the simultaneous detection of Cl-, NO2-, NO3- and SO4(2-).
(17) The other, a Pseudomonas species, was shown to respire selenate to selenite.
(18) Young striped bass (Morone saxatilis) with uninflated gas bladders were less sensitive to selenate and more sensitive to selenite exposure than normally developing striped bass in 96-hour acute toxicity tests.
(19) The D-glucose uptake was also stimulated by metavanadate, but not by selenite, selenate, or molybdate.
(20) Selenium transport across the ileum did not occur against a concentration gradient when selenite instead of selenate was present in the incubation medium.
Selenium
Definition:
(n.) A nonmetallic element of the sulphur group, and analogous to sulphur in its compounds. It is found in small quantities with sulphur and some sulphur ores, and obtained in the free state as a dark reddish powder or crystalline mass, or as a dark metallic-looking substance. It exhibits under the action of light a remarkable variation in electric conductivity, and is used in certain electric apparatus. Symbol Se. Atomic weight 78.9.
Example Sentences:
(1) It was tested for recovery and separation from other selenium moieties present in urine using both in vivo-labeled rat urine and human urine spiked with unlabeled TMSe.
(2) Dietary factors affect intestinal P450s markedly--iron restriction rapidly decreased intestinal P450 to beneath detectable values; selenium deficiency acted similarly but was less effective; Brussels sprouts increased intestinal AHH activity 9.8-fold, ECOD activity 3.2-fold, and P450 1.9-fold; fried meat and dietary fat significantly increased intestinal EROD activity; a vitamin A-deficient diet increased, and a vitamin A-rich diet decreased intestinal P450 activities; and excess cholesterol in the diet increased intestinal P450 activity.
(3) Mice exhibiting this suppression of immunity had levels of blood glutathione peroxidase, serum selenium, and liver DNA, RNA and protein similar to mice receiving selenium only.
(4) Excess levels of selenium (2.5 and 5 ppm) in the vitamin E-deficient diet had little or no effect on spleen size or hematocrit of rats not receiving lead, but partially prevented the splenomegaly and anemia of red cells from either non-poisoned or lead-oisoned vitamin E-deficient rats, but not as effectively as vitamin E. These results show that vitamin E status of rats is more important that selenium status in determining response to toxic levels of lead.
(5) Plasma selenium concentration and glutathione peroxidase activity in the subjects who died within 1 year of screening were 89% and 88%, respectively, of the values among survivors (p less than 0.01).
(6) Although selenium deficiency in livestock is consequently now rare in Oregon, selenium-deficient soils and attendant selenium deficiency conditions have been reported near the Kesterson Wildlife Refuge in the Northern part of the San Joaquin Valley, California, where, paradoxically, selenium toxicity in wildfowl, nesting near evaporation ponds, occurred and attracted wide attention.
(7) The synthetic "C" nucleoside, tiazofurin (2-beta-D-ribofuranosylthiazole-4-carboxamide), its selenium analogue selenazofurin, and the related inhibitor of inosine 5'-phosphate (IMP) dehydrogenase, mycophenolic acid, are effective inducers of the terminal differentiation of HL-60 promyelocytic leukemia cells.
(8) Thus, in this population with intermediate selenium intake, low serum selenium is not associated with an excess risk of myocardial infarction.
(9) Liver, blood, kidney and lungs were found to contain most of the selenium, here also a two-phased elimination was observed.
(10) These findings suggest that neither serum levels of selenium nor those of retinol have an appreciable effect on the risk of cancer.
(11) The incidences of esophageal tumors were statistically not significant among rats on normal, high and low selenium intake (P greater than 0.05).
(12) Alteration of guinea pig erythrocyte superoxide dismutase activity by the dietary antioxidants ascorbic acid and selenium was investigated.
(13) The more severe was the PIH the lower was the selenium level.
(14) Significantly lower selenium values were observed in blood from colorectal cancer patients than from normal individuals (0.1349 ppm vs. 0.1502 ppm.
(15) Selenium-deficient rats were used to examine the nature of the oxidant stress.
(16) Although treatment with beta-carotene tended to decrease the incidence and number of large intestinal carcinomas, beta-carotene, selenium, esculin and eugenol all decreased the incidence of kidney nephroblastomas, the differences were not statistically significant.
(17) These studies were designed to measure leukotriene B4 (LTB4) production by polymorphonuclear leukocytes (PMN) from selenium (Se)-deficient and Se-adequate goats.
(18) Copper deficiency impairs cell-mediated immunity, as does selenium deficiency when it is associated with vitamin E lack.
(19) Many forms of selenium supplement are commercialized.
(20) The possibility that a sub-clinical deficiency of the trace element selenium might exist in a sample of the British population was examined by giving a selenium supplemented for 5 weeks.