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31.
A validated LC‐MS/MS method for the determination of canagliflozin,a sodium–glucose co‐transporter 2 (SGLT‐2) inhibitor,in a lower volume of rat plasma: application to pharmacokinetic studies in rats
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Shinji Kobuchi Kyoka Yano Yukako Ito Toshiyuki Sakaeda 《Biomedical chromatography : BMC》2016,30(10):1549-1555
Canagliflozin is a novel, orally selective inhibitor of sodium‐dependent glucose co‐transporter‐2 (SGLT2) for the treatment of patients with type 2 diabetes mellitus. In this study, a validated liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method for the quantitative analysis of canagliflozin in a lower volume of rat plasma (0.1 mL) was established and applied to a pharmacokinetic study in rats. Following liquid–liquid extraction by tert‐butyl methyl ether, chromatographic separation of canagliflozin was performed on a Quicksorb ODS (2.1 mm i.d. × 150 mm, 5 µm size) using acetonitrile–0.1% formic acid (90:10, v/v) as the mobile phase at a flow rate of 0.2 mL/min. The detection was carried out using an API 3200 triple‐quadrupole mass spectrometer operating in the positive electrospray ionization mode. Selected ion monitoring transitions of m/z = 462.0 [M + NH4]+ → 191.0 for canagliflozin and m/z = 451.2 [M + H]+ → 71.0 for empagliflozin (internal standard) were obtained. The validation of the method was investigated, and it was found to be of sufficient specificity, accuracy and precision. Canagliflozin in rat plasma was stable under the analytical conditions used. This validated method was successfully applied to assess the pharmacokinetics of canagliflozin in rats using 0.1 mL rat plasma. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
32.
Laser-diode pumped heavy-doped Yb:YAG ceramic lasers 总被引:1,自引:0,他引:1
Laser performance of heavy-doped Yb:YAG ceramics was investigated using a two-pass pumping miniature laser configuration. Slope efficiency of 52% and optical-to-optical efficiency of 48% have been achieved for 1-mm-thick YAG ceramic doped with 20 at.% ytterbium ions. Laser spectra of Yb:YAG ceramic and single-crystal lasers were addressed under different intracavity laser intensities. Heavy-doped Yb:YAG ceramic is more suitable for a thin disk laser than a single-crystal with the same Yb(3+)-ion lasants. 相似文献
33.
We propose and demonstrate generation of an in-phase optical pulse train from an optical beat signal. The proposed method is based on four-wave mixing occurring between the two continuous waves of the beat signal and on spectral filtering to shape the spectrum to be symmetric about the carrier frequency. We perform an experiment to verify the proposed method and obtain a 1.5 ps width in-phase pulse train from a 160 GHz beat signal. Furthermore, we employ a pulse compression scheme to reshape and compress the obtained pulse train, and we show that a 160 GHz repeating, 0.7 ps FWHM, nearly transform-limited, in-phase sech pulse train is successfully generated. 相似文献
34.
35.
Toriya S Tamura Y Takei T Fuji M Watanabe T Chikazawa M 《Journal of colloid and interface science》2002,255(1):171-176
The silica-pillared derivatives from kanemite (NaHSi(2)O(5).3H(2)O) were prepared by intercalation of dialkyldimethylammonium (DADMA) ion and pillaring with tetraethylorthosilicate. The formation of silica pillars between the silicate sheets was demonstrated by X-ray diffraction, (29)Si CP/MAS NMR, and TEM observation. The basal spacing depended on the chain length of DADMA. Nitrogen adsorption study showed that the specific surface area was enlarged over 1000 m(2) g(-1) by the pillaring and that the pore size was in the micropore region. Water and benzene adsorption isotherms revealed that the surface properties of the pillared derivatives show hydrophobic character. 相似文献
36.
Yagi S Iwanaga T Kojima H Shoji Y Suzuki S Seno K Mori H Tokura Y Takigawa M Moriwaki S 《Photochemistry and photobiology》2002,76(6):669-671
We have developed a UV monitor with polycrystalline (poly-) gallium nitride (GaN) UV sensors and evaluated its performance from the viewpoint of its effectiveness for use with photosensitive dermatosis patients. The poly-GaN UV sensor is sensitive to UV light from 280 to 410 nm even without optical filters. The UV monitor is a portable self-data-acquisition instrument with a minimum detection level (defined as average UV intensity over 290 to 400 nm) of 2 microW/cm2 and can store UV dose data for 128 days. It allows easy measurement of four orders of magnitude of ambient UV intensity and dose from indoor light to direct solar radiation in summer. Trial use of the UV monitor by five xeroderma pigmentosum patients started in June 2000 and was carried out for 1 year. It was demonstrated that the UV monitor was useful in improving their quality of life. 相似文献
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38.
The reaction of silyldibromomethyllithium with aromatic imines provides alpha-amino acylsilanes via a bromo aziridine intermediate upon quenching the reaction with water. Alternatively, treatment of the bromo aziridine intermediate with various Grignard reagents or lithium aluminum hydride permits the nucleophilic displacement of the halogen to furnish substituted silyl aziridines. 相似文献
39.
The quasilinear degenerate evolution equation of parabolic type
0< t T considered in a Banach space X is written, putting Mv = u, in the from
0< t T, where A(u)=L(u)M–1 are multivalued linear operators in X for u K, K being a bounded ball ||u||Z<R in another Banach space Z continuously embedded in X. Existence and uniqueness of the local solution for the related Cauchy problem are given. The results are applied to quasilinear elliptic-parabolic equations and systems. 相似文献
40.
Nakano K Kawata S Yoneda K Fuyuhiro A Yagi T Nasu S Morimoto S Kaizaki S 《Chemical communications (Cambridge, England)》2004,(24):2892-2893
The variable temperature magnetic susceptibility, X-ray crystallography, and IR and Raman spectra of a new dinuclear complex [{Fe(II)(NCBH(3))(4-phpy)}(2) mu-bpypz)(2)] demonstrated the first two-step spin-crossover associated with a 1 : 1 mixture of high-spin pair [HS-HS] and low-spin pair [LS-LS] at the plateau. 相似文献