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991.
992.
Novel rapid liquid chromatography tandem masspectrometry method for vemurafenib and metabolites in human plasma,including metabolite concentrations at steady state 下载免费PDF全文
Svante Vikingsson Malin Strömqvist Anna Svedberg Johan Hansson Veronica Höiom Henrik Gréen 《Biomedical chromatography : BMC》2016,30(8):1234-1239
A novel, rapid and sensitive liquid chromatography tandem–mass spectrometry method for quantification of vemurafenib in human plasma, that also for the first time allows for metabolite semi‐quantification, was developed and validated to support clinical trials and therapeutic drug monitoring. Vemurafenib was analysed by precipitation with methanol followed by a 1.9 min isocratic liquid chromatography tandem masspectrometry analysis using an Acquity BEH C18 column with methanol and formic acid using isotope labelled internal standards. Analytes were detected in multireaction monitoring mode on a Xevo TQ. Semi‐quantification of vemurafenib metabolites was performed using the same analytical system and sample preparation with gradient elution. The vemurafenib method was successfully validated in the range 0.5–100 μg/mL according to international guidelines. The metabolite method was partially validated owing to the lack of commercially available reference materials. For the first time concentration levels at steady state for melanoma patients treated with vemurafenib is presented. The low abundance of vemurafenib metabolites suggests that they lack clinical significance. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
993.
994.
M. P.?Westig R.?Engels K.?Grigoryev M.?Mikirtytchiants F.?Rathmann H.?Paetz gen. Schieck G.?Schug A.?Vasilyev H.?Str?her 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,57(1):27-32
A Lamb-shift polarimeter, which has been built for a fast
determination of the polarization of protons and deuterons of an
atomic-beam source and which is frequently used in the ANKE
experiment at COSY-Jülich, is shown to be an excellent device for
atomic-spectroscopy measurements of metastable hydrogen isotopes. It
is demonstrated that magnetic and electric dipole transitions in
hydrogen can be measured as a function of the external magnetic
field, giving access to the full Breit-Rabi diagram for the
22S1/2 and the 22P1/2 states. This will allow the study
of hyperfine structure, g factors and the classical Lamb shift.
Although the data are not yet competitive with state-of-the-art
measurements, the potential of the method is enormous, including a
possible application to anti-hydrogen spectroscopy. 相似文献
995.
Novel intermediates based on the Corey skeleton for preparation of the ω-chain of non-halogenated unnatural prostaglandin analogues containing a triple bond at position 13–14 (PG numbering) were synthesized. The utilization of a novel synthetic approach towards a new tin intermediate, and subsequent Stille coupling opens up new possibilities for preparing these important pharmaceutical intermediates. 相似文献
996.
Karol Sza?owski Tadeusz BalcerzakAndrej Bobák 《Journal of magnetism and magnetic materials》2011,323(15):2095-2102
The thermodynamics of a site-diluted ferromagnetic Heisenberg model for spin S=1/2 with interaction anisotropy in spin space is investigated. The study is aimed at presenting the magnetocaloric properties of such a model, including the entropy and temperature changes in magnetization/demagnetization processes, generalized Grüneisen ratio as well as the quantities characterizing the efficiency of magnetic cooling cycles. The results are obtained using pair approximation (PA) method and extensively compared with the molecular field approximation (MFA) calculations. The importance of interaction anisotropy and site-dilution is discussed. The inadequacy of the MFA approach (even on the qualitative level) is found for selected quantities, while PA provides the results which are consistent with the experimentally observed behavior. 相似文献
997.
<正>SnO_2 nanorods were deposited on the Si substrates in an aqueous solution containing both SnCl_4 and CO(NH_2)_2.It is found that different self-assembled patterns of SnO_2 nanorods can be obtained by changing the deposition conditions such as the molar ratio of CO(NH_2)_2 to SnCl_4 and the pretreatment of the substrate.Scattered SnO_2 nanorods,for example,can be changed into flower-like patterns when the molar ratio of CO(NH_2)_2 to SnCl_4 is raised,and well-aligned nanorod arrays can be formed when the pretreatment of the substrate is changed.In addition,some interesting patterns,e.g.tree-like patterns,can also be observed. 相似文献
998.
999.
Dmitrij Bondarev Jiří Zedník Ivana Šloufová Ahmed Sharf Marek Procházka Jiří Pfleger Jiří Vohlídal 《Journal of polymer science. Part A, Polymer chemistry》2010,48(14):3073-3081
High‐regioregular poly{3‐[6‐(1‐methylimidazolium‐3‐yl)hexyl]thiophene‐2,5‐diyl bromide}, PMHT‐Br, has been prepared by reaction of high‐regioregular (above 92%) poly[3‐(6‐bromohexyl)thiophene‐2,5‐diyl] with 1‐methylimidazole. PMHT‐Br is soluble in water and water miscible solvents such as methanol, DMSO and shows solvatochromism; λmax (nm): 423 (H2O); 435 (MeOH); 452 (DMSO). Increased absorption band broadening observed for aqueous solution as well as NMR spectra in D2O suggests a micelle‐like structure of PMHT‐Br molecules in these solutions: poly(3‐hexylthiophene) core and 1‐methylimidazolium bromide shell. Despite the disturbing effect of ionic groups, the solid‐state PMHT‐Br shows absorption maximum at 520 nm, the band edge at 660 nm (ca. 1.9 eV), and fluorescence emission with maximum at 635 nm, in a good agreement with the polymer regioregularity. Fluorescence emission maxima: λem (nm): 598 (H2O); 562 (MeOH); 574 (DMSO), occur in a vicinity of corresponding adsorption band edges. Plot of electrical conductivity of PMHT‐Br (measured under the dynamic vacuum conditions, 5 × 10?5 Pa) versus 1/T shows a break at about 70 °C same as the temperature dependence of λmax of the solid PMHT‐Br. These breaks indicate an increase in the mobility of polymer segments and ions within PMHT‐Br; however, a thermal analysis did not provide solid evidence for it. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3073–3081, 2010 相似文献
1000.
Ravi P. Agarwal Donal O’Regan Svatoslav Staněk 《Central European Journal of Mathematics》2009,7(4):694-716
The paper is concerned with existence results for positive solutions and maximal positive solutions of singular mixed boundary
value problems. Nonlinearities h(t;x;y) in differential equations admit a time singularity at t=0 and/or at t=T and a strong singularity at x=0. 相似文献