(n.) That property which some transparent bodies have of producing at their surface, or within their substance, light different in color from the mass of the material, as when green crystals of fluor spar afford blue reflections. It is due not to the difference in the color of a distinct surface layer, but to the power which the substance has of modifying the light incident upon it. The light emitted by fluorescent substances is in general of lower refrangibility than the incident light.
Example Sentences:
(1) The assembly reaction is accompanied by characteristic changes in fluorescence emission and dichroic absorption.
(2) Such an increase in antibody binding occurred simultaneously with an increase in the fluidity of surface lipid regions, as monitored by fluorescence depolarization of 1-(trimethylammoniophenyl)-6-phenyl-1,3,5-hexatriene.
(3) The dependence of fluorescence polarization of stained nerve fibres on the angle between the fibre axis and electrical vector of exciting light (azimuth characteristics) has been considered.
(4) The sensitivity of an indirect fluorescent antibody (IFA) test (screening test) for the detection of antibodies to cytomegalovirus (CMV) was examined by using 128 serum specimens and quaternary aminoethyl (QAE)-Sephadex A50 column chromatography to separate IgM from IgG class antibodies.
(5) Absorbance or fluorescence measurements may be used for detection.
(6) In the present study, 125 oesophageal biopsies obtained under direct vision at endoscopy from 22 patients with Barrett's oesophagus were systematically studied using fluorescence and peroxidase antiperoxidase single and double-staining immunocytochemical methods employing highly specific antibodies to localize the following peptide-containing cell types in Barrett's mucosa: gastrin, somatostatin, gastric inhibitory polypeptide, motilin, neurotensin and pancreatic glucagon.
(7) Likewise, they had little or no effects on the fluorescence anisotropy of TMA-DPH, which is also thought to be located in the interfacial region of the lipid bilayer, either when the probe was located in the outer layer of the plasma membrane or when the probe was located in the inner membrane compartment.
(8) Furthermore, experiments with the fluorescence-activated cell sorter revealed increased forward light scatter from resting exudate PMN compared to blood PMN.
(9) Sulphuric acid fluorescence is used for quantitation and specificity is achieved by the addition of tritiated oestrone to the urine hydrolysate.
(10) At the light-microscopic level, adrenergic fibres were identified due to their formaldehyde-induced fluorescence.
(11) Equilibrium and kinetic studies of the interaction of gene 32 protein of T4 phage with single-stranded fd DNA were performed monitoring the changes in protein fluorescence.
(12) The drug is extracted from serum or urine with ethyl acetate, separated by TLC, and determined by fluorescence quenching densitometry.
(13) In all these subjects, fluorescent staining and G-banding on chromosomes from cultured leukocytes confirmed their karyotype.
(14) Vital staining of neuroblastoma cells with acridine orange produces a bright intracellular red-orange fluorescence most probably due to the occurrence of RNA.
(15) Time-resolved tyrosine fluorescence anisotropy shows global correlation times broadly in agreement with the NMR results, but with an additional faster correlation time [approximately 600 ps].
(16) The specific fluorescence was affected following reserpine or 6-hydroxydopamine treatment; however, the rewarming process restored fluorescence only in the reserpine-treated tissue.
(17) I evaluated use of the fluorescence polarization technique to measure neocarzinostatin, a proteinaceous antitumor antibiotic, and its antibody, in serum.
(18) In the analysis of background fluorescence, the principal components were, as for the two-step technique, autofluorescence and propidium spectral overlap.
(19) Luminal and myoepithelial cells have been separated from normal adult human breast epithelium using fluorescence activated cell sorting.
(20) The influence of exogenous gangliosides on the structure of the viral envelope was studied using fluorescent and photoactivatable phospholipids incorporated into the viral membrane.
Phosphorescence
Definition:
(n.) The quality or state of being phosphorescent; or the act of phosphorescing.
(n.) A phosphoric light.
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.