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991.
Tomoko Matsuda Kazuro Ikawa Kayo Ikeda Norifumi Morikawa Ryu Tsumura Masaaki Shibukawa Koji Iida Kaoru Kurisu 《Chromatographia》2009,69(9-10):1031-1034
A simple, rapid and accurate liquid chromatography method using ultrafiltration to pretreat cerebrospinal fluid (CSF) samples was developed to determine meropenem concentrations in human CSF in clinical settings. Meropenem in CSF samples was stabilized by mixing with 1 mol L?1 3-morpholinopropanesulfonic acid buffer (pH 7.0) (1:1). The mixture was transferred to a Nanosep 10 K centrifugal filter device; after centrifugation, the filtrate was subjected to reversed-phase LC and the eluate was monitored at 300 nm. The retention time for meropenem was 5.8 min. The calibration curve of meropenem in human CSF was linear over 0.05–50 μg mL?1. The intra-day and inter-day precision was 0.27–5.66 % and accuracy was 99.0–109.5 %. The limit of detection was 0.01 μg mL?1. This method was successfully applied to neurosurgical patients, showing that it is applicable for therapeutic drug monitoring in patients receiving meropenem. 相似文献
992.
Treatment of 1-chlorovinyl p-tolyl sulfoxides, derived from cyclobutanones and chloromethyl p-tolyl sulfoxide, with lithium enolate of carboxylic acid tert-butyl esters, lithium enolate of carboxylic acid N,N-dimethylamides, or lithium α-carbanion of alkyl phenyl sulfones gave adducts in high yields. The adducts were treated with isopropylmagnesium chloride or ethylmagnesium chloride in dry toluene to give esters, amides, and sulfones bearing a 1-cyclopentenyl group at the α-position in moderate to good yields with one-carbon ring-expansion via magnesium carbenoid 1,2-CC insertion reaction. The magnesium carbenoid 1,2-CC insertion reaction proved to be highly stereospecific. The reaction mechanism and origin of the specificity are described. 相似文献
993.
994.
Synthesis and photovoltaic properties of thieno[3,4‐b]pyrazine or dithieno[3′,2′:3,4;2″,3″:5,6]benzo[1,2‐d]imidazole‐containing conjugated polymers 下载免费PDF全文
Mukhamed L. Keshtov Dmitri Yu. Godovsky Alexei R. Khokhlov Tetsunari Mizobe Hiroyuki Fujita Eisuke Goto Junya Hiyoshi Saki Nakamura Susumu Kawauchi Tomoya Higashihara Tsuyoshi Michinobu 《Journal of polymer science. Part A, Polymer chemistry》2015,53(9):1067-1075
Novel conjugated polymers composed of benzo[1,2‐b:4,5‐b′]dithiophene and thieno[3,4‐b]pyrazine or dithieno[3′,2′:3,4;2″,3″:5,6]benzo[1,2‐d]imidazole units are synthesized by Stille polycondensation. The resulting polymers display a longer wavelength absorption and well‐defined redox activities. The effective intramolecular charge‐transfer and energy levels of all polymers are elucidated by computational calculations. Bulk‐heterojunction solar cells based on these polymers as p‐type semiconductors and [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) as an n‐type semiconductor are fabricated, and their photovoltaic performances are for the first time evaluated. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1067–1075 相似文献
995.
Tsuyoshi Oshima Iori Yamanaka Anupriya Kumar Junichiro Yamaguchi Taeko Nishiwaki‐Ohkawa Kei Muto Rika Kawamura Tsuyoshi Hirota Kazuhiro Yagita Stephan Irle Steve A. Kay Takashi Yoshimura Kenichiro Itami 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(24):7299-7303
The synthesis and functional analysis of KL001 derivatives, which are modulators of the mammalian circadian clock, are described. By using cutting‐edge C H activation chemistry, a focused library of KL001 derivatives was rapidly constructed, which enabled the identification of the critical sites on KL001 derivatives that induce a rhythm‐changing activity along with the components that trigger opposite modes of action. The first period‐shortening molecules that target the cryptochrome (CRY) were thus discovered. Detailed studies on the effects of these compounds on CRY stability implicate the existence of an as yet undiscovered regulatory mechanism. 相似文献
996.
Magnesium carbenoids were generated from aryl 1-chloroalkyl sulfoxides with i-PrMgCl in THF at low temperature in quantitative yields. The magnesium carbenoids were found to be reactive with N-lithio alkylamines to afford an olefin, which was derived from dimerization of the magnesium carbenoid, in moderate yield. On the other hand, reaction of the magnesium carbenoids with N-substituted N-lithio arylamines gave non-stabilized α-amino-substituted carbanions in good yields. Reactivity of the α-amino-substituted carbanions with some electrophiles was investigated and it was found that ethyl chloroformate reacted to give α-amino acid derivatives in good yields. As a whole, a new method for one-pot, three-component combined synthesis of α-amino acid derivatives from aryl 1-chloroalkyl sulfoxides was realized. 相似文献
997.
Tsuyoshi Kato 《Geometric And Functional Analysis》2009,19(3):883-901
In this paper we study analytic properties of orbits given by real rational functions. We introduce some comparison methods
which allow us to compare the real rational dynamics with automata given by (max, +) functions, passing through a kind of
scale transform in tropical geometry. Such a scale transform gives a one-to-one correspondence of presentations between automata
and real rational functions. We study invariant properties of the real rational dynamics under change of presentations of
automata. 相似文献
998.
Yuji Ikeda Masashi Nishigaki Masamichi Ippommatsu Tsuyoshi Nakajima 《Particle & Particle Systems Characterization》1994,11(2):127-132
Seeding particles for laser Doppler velocimeter (LDV) measurement have been developed which are of uniform diameter, spherical shape, low loose weight and high melting temperature. Evaluation test results show that the use of the particles can increase the signal quality substantially and extend the measurable field of the LDV, which can hardly be accessed by conventional measurement methods. 相似文献
999.
1000.
Kazunori Tanimura Tsuyoshi Konishi Yoshinori Oshita Wanji Yu Kazuyoshi Itoh 《Optical Review》2004,11(1):12-18
In measurement of ultrafast phenomena caused by several photochemical reactions, multiple transitional spectral patterns contained in a signal pulse are directly associated with different interactions, allowing us to identify individual interactions from these patterns. We propose a new method by which we can detect multiple transitional spectral patterns contained in a signal pulse in parallel using optical spectrogram scope (OSS). In the experimental demonstration, we used an arrayed filter composed of matched filters recording three kinds of transitional spectral patterns in the OSS system, and we directly detected two different patterns contained in a signal pulse in parallel. 相似文献