(a.) Shining with a phosphoric light; luminous without sensible heat.
(n.) A phosphorescent substance.
Example Sentences:
(1) Fluorescence and phosphorescence spectra and lifetime studies revealed that at least 75% of the porphyrins were bound to metal, probably Zn, while the rest was free.
(2) The inactivation of equine liver alcohol dehydrogenase by guanidine hydrochloride and urea has been studied by monitoring the intrinsic tryptophan fluorescence and phosphorescence emission.
(3) The constancy of the lifetime-normalized phosphorescence yield with apoazurin and with Trp-314 in alcohol dehydrogenase establishes that the intersystem crossing quantum yield is practically unaffected across the temperature range.
(4) The quantum yields for singlet oxygen formation via energy transfer from triplet alpha-terthienyl have been obtained from time-resolved measurements of its IR phosphorescence: these yields are in the 0.6-0.8 range in non-polar and polar (hydroxylic and non-hydroxylic) solvents.
(5) When pouring liquid nitrogen over the spots, a very intense bluish-white fluorescence followed by a long-lasting greenish phosphorescence is observed.
(6) Triphenylene was also extemporaneously determined by its phosphorescence spectrum at low temperature.
(7) 1O2 phosphorescence emission was enhanced in deuterated buffer and upon saturation of the sample with oxygen and could be quenched by the addition of sodium azide to the external medium.
(8) High-quality phosphorescence decay curves with a 10-microseconds time resolution were obtained at concentrations of the eosin probe down to 20 nM and in aqueous media at temperatures of 4-38 degrees C. A strong temperature dependence in the rotational behavior was observed for the band 3 anion transport protein, but the lectin receptors of the Friend erythroleukemia cells were found to be immobile on the time scale of 1-4000 microseconds at either 4 degrees C or 37 degrees C. The technique is applicable to other triplet probes and membrane components of living cells under conditions that do not destroy viability.
(9) Quantum yields, fluorescence decay times and phosphorescence of Yt base have been also determined.
(10) Samples of Precambrian rocks (1.7-2.6 billion years, U.S.S.R.) contain metalloporphyrins and linear tetrapyrrole pigment similar to phycobilin 655 from modern blue-green algae Microystis (according to data of phosphorescence spectroscopy).
(11) Barring major enzyme conformational changes in the vicinity of unmodified tryptophan residues when Trp-62 or Trp-108 are selectively modified, we find that Trp-108 dominates both the phosphorescence and the ODMR signals in native lysozyme.
(12) The second-order rate constants, k delta, for quenching of molecular singlet oxygen O2 (1 delta g) by nonsteroidal anti-inflammatory imidazole drugs have been determined using time-resolved phosphorescence detection of singlet oxygen.
(13) Images of the phosphorescence were collected using a series of different delay times after illumination with a light flash (less than 5-microseconds width at half-height), and the phosphorescence decay constants (lifetimes) and oxygen pressure were calculated for each pixel of the image arrays.
(14) Upon irradiation, a solution of porphyrins containing more than 0.1% HSA shows phosphorescence with a lifetime longer than 1 ms. With an increase in irradiation time, phosphorescence intensities and lifetimes of porphyrins increase, depending upon their concentrations and triplet lifetimes, and approach saturated values close to those under deaerated conditions.
(15) Changes in conformation of glutamate dehydrogenase from beef liver as a result of interactions with allosteric effectors have been demonstrated from the phosphorescence emission of tryptophan.
(16) In addition, at 77 K and 275 nm 4-fluorotryptophan displayed strong fluorescence and phosphorescence, with emission quantum yields comparable with those of tryptophan at 77 K and 275 nm.
(17) The phosphorescence spectra and phosphorescence excitation spectra as well as the ratio of fluorescence and phosphorescence yields and the triplet state lifetume have been measured.
(18) Its phosphorescence decay fits well to two exponential components of 1.02 and 0.12 s, with no contribution from long-lived Trp residues.
(19) The mammalian heterogeneous ribonucleoprotein (hnRNP) A1 and its constituent N-terminal domain, termed UP1, have been studied by steady-state and dynamic fluorimetry, as well as phosphorescence and optically detected magnetic resonance (ODMR) spectroscopy at cryogenic temperatures.
(20) The phosphorescence 0,0 band as well as the zero-field splittings of Trp-134 undergoes significant changes upon binding of oleic acid to BSA.
Phosphorus
Definition:
(n.) The morning star; Phosphor.
(n.) A poisonous nonmetallic element of the nitrogen group, obtained as a white, or yellowish, translucent waxy substance, having a characteristic disagreeable smell. It is very active chemically, must be preserved under water, and unites with oxygen even at ordinary temperatures, giving a faint glow, -- whence its name. It always occurs compined, usually in phosphates, as in the mineral apatite, in bones, etc. It is used in the composition on the tips of friction matches, and for many other purposes. The molecule contains four atoms. Symbol P. Atomic weight 31.0.
(n.) Hence, any substance which shines in the dark like phosphorus, as certain phosphorescent bodies.
Example Sentences:
(1) In the liver of albino rats with experimental thyrotoxicosis a study was made of nucleic acids and some indices of phosphorus metabolism: total and inorganic phosphorus, total and acid-soluble phosphorus, phosphorus of RNA, DNA and phosphoproteins.
(2) Hypertonic saline infusion induced significant (P less than 0.05) increases in serum Na and Cl concentrations and osmolality, whereas ISS induced a significant increase in serum Cl concentration and a significant decrease in serum phosphorus concentration.
(3) A low-protein, low-phosphorus diet supplemented with essential amino acids and keto analogues was given to 12 rats, starting from the 90th day after subtotal nephrectomy.
(4) In comparison with native counterparts, the in vitro-formed LDL2 and HDL + VHDL were characterized by lower levels of triglyceride and cholesterol ester and higher levels of free cholesterol and lipid phosphorus.
(5) Unsupplemented human breast milk may not provide sufficient calcium and phosphorus for the rapidly growing preterm infant to match the accumulation that should have taken place in utero and to permit normal bone mineralization.
(6) In 9 other patients studied 2-7 years after transplantation the mean level of parathormone was lower than in the previous group but levels above normal were noted in half of the patients, some of which had perfect renal function and normal serum phosphorus.
(7) The treatment regimens used were chemotherapy in 9 patients, antiaggregating agents in 7, radioactive phosphorus in 1, the newer platelet-lowering agent anagrelide in 10, and only observation in 29.
(8) Phosphorus in fibrinogen did not correlate with fibrinogen degradation products or fibrinogen levels and became normal on adequate anticoagulation.
(9) The effect of age of the ewe and pregnancy on concentrations of plasma calcium, phosphorus and magnesium and its relationship to the bent-leg syndrome in lambs, were investigated.
(10) Reports in the past two years have appeared evaluating the clinical use of phosphorus spectroscopy to detect ischemic heart disease, cardiomyopathy, and cardiac transplant rejection.
(11) Blood calcium and phosphorus, parathyroid hormone, urinary excretion of calcium were determined.
(12) The raw data are obtained by capillary gas chromatography using a nitrogen-phosphorus detector.
(13) In order to examine the mechanisms underlying radiation-induced changes in phosphorus metabolite levels observed in RIF-1 tumors in vivo, RIF-1 cells in culture were perfused for up to 70 h following gamma-irradiation with 0-25 Gy and monitored continuously by 31P NMR spectroscopy at 8.5 T. Cells immobilized in the sample volume by incorporation into calcium alginate beads were bioenergetically stable, but did not replicate at the cell density used.
(14) With increasing H2O2 concentration in the perfusion media there was a corresponding decrease in the observed phosphorus metabolites, phosphorylcholine and ATP.
(15) All calcium, magnesium, and zinc contents per bone decreased in the 1- and 2-mg caffeine groups as compared to either controls or 0.5-mg caffeine group, whereas phosphorus stayed relatively constant regardless of the different levels of caffeine intake.
(16) 77 p. 100 of those fluids present an antibacterial activity, but no correlation has been found with their concentration in zinc and phosphorus.
(17) The basal diet which contained .30% phosphorus and .21% calcium was adjusted to contain added phosphorus levels of 0, .05, .10, or .15%, with calcium levels of .49, .47, .57 and .61%, respectively.
(18) In 50% of the animals lactate increased prior to any change in the phosphorus metabolites or intracellular pH, suggesting that 1H NMR may be more sensitive than 31P NMR at detecting hypoxic or ischaemic changes.
(19) Ferrihydrite was the predominant form of iron present in both ferritin and haemosiderin, while haemosiderin contained higher amounts of phosphorus, magnesium, calcium and barium, then either normal or ferrocene-loaded ferritin.
(20) Plasma levels of both phosphorus and urate fell during this time.