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71.
Yoshimatsu K Kiuchi F Shimomura K Makino Y 《Chemical & pharmaceutical bulletin》2005,53(11):1446-1450
A rapid and reliable solid-phase extraction method for HPLC analysis of opium alkaloids from Papaver plants was established. Fifty mg of dried and powdered plant sample was extracted with 5 ml of 5% acetic acid for 30 min under sonication. After centrifugation, 3 ml of the supernatant was loaded on a reversed-phase cation-exchange solid-phase extraction cartridge. After seriate washings with 0.1 M hydrochloric acid and methanol, alkaloids were eluted with a mixture of 28% ammonia and methanol (1:19). The eluate was concentrated under nitrogen stream at 40 degrees C and the residue was dissolved in 50% aqueous methanol for high performance liquid chromatographic analysis. With this solid-phase extraction method, the recovery of morphine, codeine, oripavine, thebaine, papaverine, noscapine and sanguinarine was from 99.94 to 112.18% when the standard alkaloids were added to the plant samples. Opium alkaloids of a variety of genus Papaver plants cultivated in a field and phytotron were analyzed by this method. 相似文献
72.
Quantitative determination of the fatty acid composition of human serum lipids by high-performance liquid chromatography 总被引:2,自引:0,他引:2
A high-performance liquid chromatographic method for the analysis of the fatty acid composition of human serum lipids with fluorescence detection was examined. Both free and total fatty acids extracted from serum were derivatized with 9-anthryldiazomethane and were analysed using methanol-water (94.7:5.3) as mobile phase. Twelve kinds of fatty acid were detected, both in the free and total fatty acids, and were well separated. Concentrations of individual fatty acids of serum lipids were estimated from an internal standard, heptadecanoic acid. The results correlated well with those from two other quantitative analyses. These results indicate that the high-performance liquid chromatographic analysis of fatty acids is a reliable method for determining individual fatty acids of human serum lipids. The compositions of free fatty acids and total fatty acids of serum lipids were analysed and compared in 27 normal subjects, 27 diabetics, and 20 angina pectoris patients by this method. 相似文献
73.
Mechanisms in the quantum yield of Cypridina bioluminescence 总被引:4,自引:1,他引:4
Abstract— –The influence of temperature, pH, salts, and reactant concentrations on the biolumin-escent oxidation of Cypridina luciferin catalyzed by Cypridina luciferase indicates a highest quantum yield φ (einsteins per mole of luciferin oxidized) of 0.31 in H2O, or 0.33 in 99% D2O. With the aid of data on fluorescence of the light-emitting oxyluciferin-luciferase complex, and of oxyluciferin in diglyme, partial explanations are suggested for the observed variations in φ, including the relatively low φ, of 0.03 for chemiluminescence of luciferin in organic solvents, wherein a different pathway of luciferin degradation, as indicated by chromatographic evidence, results in much less population of the excited state. 相似文献
74.
In this paper we are concerned with Trudinger’s inequality and continuity for general potentials of functions in Musielak–Orlicz–Morrey spaces. 相似文献
75.
Color contrast in a nematic liquid crystal display is defined experimentally. Liquid crystal cell shows a positive dielectric anisotropy and is operated in a tunable birefringence mode. Munsell color chips used as background color. Colorimetric data are shown in the 1976 CIE (L*, a*, b*) color scale. First, a predict equation of color shift induced by background color is derived and shows a good agreement with the result of experiment. Second, criterial of color contrast is established by taking into account the color shift. The values of criteria nearly coincide with that of psychophysical experiment by single-stimulur method, and the validity of criteria is confirmed. 相似文献
76.
77.
Hiromitsu Kiriyama Michiaki Mori Yoshiki Nakai Takuya Shimomura Manabu Tanoue Atushi Akutsu Hajime Okada Tomohiro Motomura Shuji Kondo Shuhei Kanazawa Akito Sagisaka Jinglong Ma Izuru Daito Hideyuki Kotaki Hiroyuki Daido Sergei Bulanov Toyoaki Kimura Toshiki Tajima 《Optics Communications》2009,282(4):625-2346
We demonstrate a high-contrast, high-intensity double chirped-pulse amplification (CPA) Ti:sapphire laser system using an optical parametric chirped-pulse (OPCPA) pre- amplifier. By injecting cleaned microjoule seed pulses into the OPCPA, a temporal contrast greater than 1010 within picosecond times before the main femtosecond pulse is demonstrated with an output pulse energy of 1.7 J and a pulse duration of 30 fs, corresponding to a peak power of 60 TW at a 10 Hz repetition rate. This system uses a cryogenically-cooled Ti:sapphire final amplifier and generates focused peak intensities in excess of 1020 W/cm2. 相似文献
78.
This Letter describes an efficient method—one that takes advantage of hydrogen bond-guided self-assembly and ruthenium-catalysed propargylic substitution—for the preparation of rotaxanes. The substitution reactions of a pseudorotaxane with a diverse range of heteroatom- and carbon-atom-centred nucleophiles were catalysed by the [(Cp∗)RuCl(SMe)]2 complex to furnish rotaxanes in good yields. 相似文献
79.
In the framework of quantum field theory, we consider the way to construct the one-particle state (with definite 3-momentum)
when particle mixing exists, such as in the case of flavor-neutrino mixing. In the preceding report (Prog. Theor. Phys. 112, 901 (2004)), we have examined the structure of expectation values of the flavor neutrino charges (at time t) with respect to a neutrino-source state prepared at time t′ (earlier than t). When there is no mixing, each of various contributions to the expectation value is equal, in its dominant part, to the
transition probability corresponding to the respective neutrino-production process. On the basis of the assumption that such
an equality holds also in the mixing case, we can find an appropriate form of one-flavor-neutrino state with 3-momentum and
helicity. Along the same way, we examine the boson case when flavor mixing exists. We give remarks on the relation and difference
between the ordinary and the present approaches to flavor oscillation.
The text was submitted by the authors in English. 相似文献
80.
Sadaaki Yamamoto Masaru Tanaka Hiroshi Sunami Keiko Arai Shigeko Yamashita Masatsugu Shimomura 《Surface science》2006,600(18):3785-3791
Substratum surface morphology plays a vital roles in cellular behavior. Here, we characterized adsorption of fibronectin (Fn) as a typical cell adhesion protein onto honeycomb-patterned films made of poly(ε-caprolactone) (PCL) by using atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). In order to determine how cells adhere to a honeycomb-patterned film, focal adhesion of cardiac myocytes (CMYs) and endothelial cells (ECs) on the films were studied by using fluorescence labeling of vinculin. Fn adsorbs around the pore edges to form ring-shaped structures. CMYs and ECs adhere onto the honeycomb-patterned films at focal contact points localized around pore edges distributed over the entire cellular surface. The focal contact points on the honeycomb-patterned films correspond well with the adsorption sites of Fn. We suggest that the cell response to honeycomb-patterned films is associated with the adsorption pattern of Fn on the film. 相似文献