(n.) A rare metallic element, of uncertain identification, supposed to exist in certain minerals, as gadolinite and samarskite, with other rare ytterbium earth. Symbol Tr or Tb. Atomic weight 150.
Example Sentences:
(1) Three classes of Tb3+-binding sites have been found: a first class of low-affinity (Kd = 10 microM) corresponds to magnesium binding sites, located near a tryptophan residue of the protein; a second class of much higher affinity (less than 0.1 microM) corresponds to the calcium transport sites, their occupancy by terbium induces the E1 to E2 conformational change of the Ca2+-ATPase; a third class of sites is revealed by following the fluorescence transfer from formycin triphosphate (FTP) to terbium, evidencing that terbium ions can also bind into the nucleotide binding site at the same time as FTP.
(2) The interaction of three second-generation anthracycline derivatives with polynucleotides, supercoiled DNA, and calf thymus nucleosomes has been studied by terbium fluorescence measurements and agarose gel electrophoresis.
(3) On treatment of the axon with certain agents that include tetrodotoxin, high calcium and terbium, the rebound disappears and the fast phase slows down, increases in size, and has a new slow component added to it.
(4) We have taken continuous thin serial sections through patches of terbium trapped between pericytes and the endothelial cells of continuous capillaries in the rete mirabile of the eel.
(5) Two terbium ions, at least, bind to the Ca2+-ATPase in the close vicinity of FTP when this nucleotide is bound to the ATPase nucleotide site.
(6) The soluble analogue, N-trifluoroacetyladriamycin-14-O-hemiadipate, did show marked effects on terbium fluorescence with all nucleic acids and nucleosomes, but the effects were generally not as striking as were those observed with the epimer, 4'-epi-Adriamycin, which tended to produce a similar effect to its parent drug, Adriamycin, showing that a marked change in the hexose ring did not appreciably affect the interaction of the drug with DNA.
(7) It was concluded that tryptophan in loop position 7 gave optimal luminescence enhancement, and that the additional inclusion of a tyrosine in the loop at positions 2 or 4 could further boost emission from the bound terbium.
(8) Terbium ions and terbium formycin triphosphate have been used to investigate the interactions between the cation and nucleotide binding sites of the sarcoplasmic reticulum Ca2+-ATPase.
(9) We report here on the effects of S-100b on cardiolipin vesicles as investigated by turbidity, terbium-dipicolinate fluorescence and freeze-fracture.
(10) The suitability of the intense Kalpha x rays of terbium emitted in the electron-capture decay of 159Dy for use in transmission imaging and bone mineral analysis is investigated.
(11) Resonance energy transfer from tryptophan residues to terbium occurred only with site A.
(12) The fluorescence excitation and emission spectra of the RNA-terbium(III) complex is reported.
(13) In order to assess their physiological effects, we have examined the action of free terbium ions on the membrane potential and light-evoked responses of horizontal cells, and on the massed light evoked response (ERG) of the neural retina.
(14) Spectroscopically active terbium ions have been used to probe the Ca2+ ion-binding sites on human plasma gelsolin.
(15) The terbium chelate was found to bind tightly (Ka approximately 10(5) M-1) to the protein with a stoichiometry of 1 chelate molecule per protein dimer.
(16) Terbium (Tb3+) competitively inhibited 45Ca2+ binding to fibrinogen during equilibrium dialysis, accelerated fibrin polymerization, and limited fibrinogen fragment D digestion by plasmin.
(17) Calcium concentration dependence shows that this effect is associated with the replacement of terbium by calcium in the transport sites, inducing the E2----E1 transconformation when calcium is bound.
(18) For two different murine monoclonal antibodies, the average chelator content obtained by terbium fluorescence titration correlated closely with that measured by the cobalt-57 binding assay.
(19) We describe an ultrasensitive, enzymatically amplified time-resolved fluorescence immunoassay of thyrotropin (thyroid-stimulating hormone) in serum with use of a terbium chelate as the detectable moiety.
(20) While the rates of activation of calpain I by terbium and calcium are comparable, the rate of activation of calpain II was much greater in the presence of terbium than in the presence of calcium.
Yttrium
Definition:
(n.) A rare metallic element of the boron-aluminium group, found in gadolinite and other rare minerals, and extracted as a dark gray powder. Symbol Y. Atomic weight, 89.
Example Sentences:
(1) These data indicate that 1) the equilibrium stability constant is not a good indicator of the in vivo stability of metal-labeled proteins and 2) it is possible to manipulate the ion distribution and therefore the dose from scandium-47 and yttrium-90 after injection of the labeled proteins.
(2) Both abscesses were drained transendoscopically by use of a contact neodymium:yttrium aluminum garnet laser.
(3) A neodymium:yttrium aluminum garnet (Nd:YAG) laser was used to study effects of applying laser irradiation transendoscopically to the corniculate process of the arytenoid cartilage in horses.
(4) It decomposes to Yttrium 90 which has a half life of 62 hours.
(5) Differences in the degree of chromosomal damage have been shown with various colloidal forms of yttrium 90, and the severity of these changes has been shown to correlate with the degree of leakage of radio-isotope to the draining lymph node rather than with whole-body irradiation.
(6) A neodymium:yttrium-aluminum-garnet (Nd:YAG) laser was used to induce highly reproducible focal cortical lesions in anesthetized rats.
(7) An elderly male patient with advanced prostatic adenocarcinoma, requiring increasing analgesia, underwent interstitial pituitary irradiation by implantation of yttrium-90.
(8) To measure the concentrations of yttrium-oxide-coated small-dispersed silicon nitride plasma powder, the air was aspirated at the amount of 10-15 litres per min through the AFA-XP filter.
(9) These data indicate that the human liver may tolerate relatively large radiation doses when delivered by Yttrium-90 microspheres embedded in the liver parenchyma as a number of discrete point sources.
(10) This article reviews holmium:YAG (yttrium-aluminum-garnet) laser physics, its tissue effects, and reports initial experience with its use in TMJ arthroscopy.
(11) Based upon the assumption that oxygen may be a key to superconductivity properties, we have also investigated the visibility of the oxygen sites as well as the heavier yttrium and barium ion positions and the lighter Cu atom positions.
(12) Removal of the lipoma was achieved with the Neodymium-Yttrium-Aluminum-Garnet (Nd:YAG) laser through a fiberoptic bronchoscope.
(13) Five patients with severe fibrous subglottic and tracheal stenosis were treated by endoscopic radial laser incision and dilation using both carbon dioxide and neodymium:yttrium aluminum garnet lasers.
(14) A technique is described using a neodymium:yttrium-aluminium-garnet (Nd:YAG) laser in combination with a special tracheoscope and high frequency jet ventilation (HFJV).
(15) Furthermore, high rates of yttrium-88 elution correlated with deposition in bone.
(16) Nine patients were treated with preoperative endobronchial neodymium:yttrium-aluminum-garnet laser resection to facilitate a lung-preserving surgical resection.
(17) We conclude that this newly devised technique for transurethral prostatectomy in the canine model can be performed safely and effectively using a Neodymium:Yttrium Aluminum Garnet laser (Neodymium:YAG).
(18) Successful imaging with this system has been performed with beta-emitters 14C, sulfur-35 (35S), iodine-131 (131I), yttrium-90 (90Y), and positron emitters gallium-68 (68Ga), and fluorine-18 (18F).
(19) In an attempt to ablate the laryngeal saccule as an alternative method of sacculectomy (conventially done through a laryngotomy incision for laryngeal hemiplegia) a neodymium:yttrium aluminum garnet laser was used transendoscopically in noncontact fashion in 6 horses.
(20) A 22-micron glass microsphere called TheraSphere (Theragenics Corp., Atlanta, GA) has been developed in which yttrium 89 oxide is incorporated into the glass matrix and is activated by neutron bombardment to form the beta-emitting isotope yttrium 90 (Y 90) before using the spheres as radiotherapeutic vehicles.