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81.
A simple high‐performance liquid chromatography for the determination of linezolid in human plasma and saliva 下载免费PDF全文
Shuuji Hara Masanobu Uchiyama Masami Yoshinari Taichi Matsumoto Shiro Jimi Atsushi Togawa Tohru Takata Yasushi Takamatsu 《Biomedical chromatography : BMC》2015,29(9):1428-1431
Linezolid is an antimicrobial agent for the treatment of multiresistant Gram‐positive infections. A practical high‐performance liquid chromatography method was developed for the determination of linezolid in human plasma and saliva. Linezolid and an internal standard (o‐ethoxybenzamide) were extracted from plasma and saliva with ethyl acetate and analyzed on a Capcell Pak C18 MG column with UV detection at 254 nm. The calibration curve was linear through the range 0.5–50 µg/mL using a 200 μL sample volume. The intra‐ and interday precisions were all <6.44% for plasma and 5.60% for saliva. The accuracies ranged from 98.8 to 110% for both matrices. The mean recoveries of linezolid were 80.8% for plasma and 79.0% for saliva. This method was used to determine the plasma and saliva concentrations of linezolid in healthy volunteers who were orally administered a 600 mg dose of linezolid. Our liquid–liquid extraction procedure is easy and requires a small volume of plasma or saliva (200 μL). This small volume can be advantageous in clinical pharmacokinetic studies, especially if children participate. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
82.
Shigeyoshi Fujiwara Ken-Ichi Imadome Masami Takei 《Experimental & molecular medicine》2015,47(1):e135
The development of highly immunodeficient mouse strains has allowed the reconstitution of functional human immune system components in mice. New-generation humanized mice generated in this manner have been extensively used for modeling viral infections that are exclusively human tropic. Epstein–Barr virus (EBV)-infected humanized mice reproduce cardinal features of EBV-associated B-cell lymphoproliferative disease and EBV-associated hemophagocytic lymphohistiocytosis (HLH). Erosive arthritis morphologically resembling rheumatoid arthritis (RA) has also been recapitulated in these mice. Low-dose EBV infection of humanized mice results in asymptomatic, persistent infection. Innate immune responses involving natural killer cells, EBV-specific adaptive T-cell responses restricted by human major histocompatibility and EBV-specific antibody responses are also elicited in humanized mice. EBV-associated T-/natural killer cell lymphoproliferative disease, by contrast, can be reproduced in a distinct mouse xenograft model. In this review, recent findings on the recapitulation of human EBV infection and pathogenesis in these mouse models, as well as their application to preclinical studies of experimental anti-EBV therapies, are described. 相似文献
83.
Kotaro Satoh Yuya Mori Masami Kamigaito 《Journal of polymer science. Part A, Polymer chemistry》2019,57(3):465-473
In this work, we examined the synthesis of novel block (co)polymers by mechanistic transformation through anionic, cationic, and radical living polymerizations using terminal carbon–halogen bond as the dormant species. First, the direct halogenation of growing species in the living anionic polymerization of styrene was examined with CCl4 to form a carbon–halogen terminal, which can be employed as the dormant species for either living cationic or radical polymerization. The mechanistic transformation was then performed from living anionic polymerization into living cationic or radical polymerization using the obtained polymers as the macroinitiator with the SnCl4/n‐Bu4NCl or RuCp*Cl(PPh3)/Et3N initiating system, respectively. Finally, the combination of all the polymerizations allowed the synthesis block copolymers including unprecedented gradient block copolymers composed of styrene and p‐methylstyrene. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 465–473 相似文献
84.
Takashi Mino Kohei Watanabe Takumu Akiyama Yuki Mizutani Kazuki Miura Masatoshi Hashimoto Yasushi Yoshida Masami Sakamoto 《Tetrahedron》2018,74(28):3871-3878
We previously reported the synthesis of BICMAP (1a) via 6-diphenylphosphino-2,3-dihydrobenzofuran as a key intermediate. However, we did not successfully synthesize BICMAP analogues via a similar synthetic route. Herein we report the second-generation synthesis of BICMAP and its derivatives via diethylphosphonate as a key intermediate. 相似文献
85.
In this paper we shall make a further study on the the equivalence problem, i.e., equivalent conditions to the Riemann hypothesis in terms of Farey series by developing a rather analytical (-arithmetical) method to establish unexpected short interval results, namely
results, therewith simultaneously clarifying the underlying reasons for
results obtained in Part I. 相似文献
86.
Resistivity and thermoelectric power were measured as a function of temperature and composition for Ge20BixSe70?xTe10 glasses (x = 0–11). The results were compared with the case of of Ge20BixSe80?x glasses to see on the electrical properties the influence of the substitution of Te for a part of Se. The glasses show n-type conduction for x ? 9, which was not affected by the substitution of Te. The resistivity was about three orders of magnitude lower for the glasses with x < 10, and remained almost the same for x ? 10, compared with the glasses not containing Te. From the composition dependence of the calculated concentration of covalent bonds in the glasses, it was proposed that the appearance of n-type conduction was closely related to the formation of a sufficient number of BiSe bonds and the disappearance of the bonds between two chalcogen atoms such as TeSe or SeSe bonds, and that the remarkably low resistivity in the present glasses with x < 10 was likely to be attributed to the formation of TeSe bonds. 相似文献
87.
Complanine, an inflammation-inducing substance isolated from the marine fireworm Eurythoe complanata
Nakamura K Tachikawa Y Kitamura M Ohno O Suganuma M Uemura D 《Organic & biomolecular chemistry》2008,6(12):2058-2060
The marine fireworm, Eurythoe complanata, is known as a dangerous animal for humans because it induces skin inflammation through its small setae. Here, the inflammation-inducing substance was successfully isolated from the whole body using a methanolic extraction, and the inflammatory activity was determined using a bioassay. The structure was spectroscopically revealed to be a trimethylammonium with an unsaturated carbon chain and was named complanine. Complanine enhanced PKC activity in combination with TPA in vitro. This may explain the molecular mechanism behind its inflammation-inducing activity. 相似文献
88.
89.
Masami Kuriyama 《Tetrahedron》2007,63(38):9393-9400
The catalyst composed of 0.25-0.025 mol % of [Pd(allyl)Cl]2 and 0.5-0.05 mol % of the thioether-imidazolium chloride 3c was proven to be efficient in the Suzuki-Miyaura cross-coupling reactions of aryl bromides with arylboronic acids. 相似文献
90.
Sakamoto M Unosawa A Kobaru S Fujita K Mino T Fujita T 《Chemical communications (Cambridge, England)》2007,(34):3586-3588
An asymmetric S(N)Ar reaction was performed by using molecular chirality generated and amplified by the spontaneous crystallization of achiral naphthamides; the chirality was retained in a cold solution, caused by slow racemization, and was transferred to stable axially chiral materials with high enantiomeric excesses. 相似文献