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81.
Zhao C Nagatsu A Hatano K Shirai N Kato S Ogihara Y 《Chemical & pharmaceutical bulletin》2003,51(3):255-261
Two new podophillotoxin glucosides, L-picropodophillotpxin 7'-O-(beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside) (2) and L-picropodophillotpxin 7'-O-beta-D-glucopyranoside (3), were isolated from Chinese medicinal plant, Sinopodophillum emodi, together with 4 known compounds, podophillotoxin (1), podorhizol 4'-O-beta-D-glucopyranoside (4), deoxypodophillotoxin (5), and dehydropodophillotoxin (6). The structures of 2 and 3 were finally determined by the extensive decouping and nuclear Overhauser effect (NOE) experiments in NMR spectra and circular dichroism (CD) spectra. Compound 2 is the second example of podophillotoxin diglucoside, and both the first one and 2 were isolated from S. emodi. X-ray crystal structure analysis of 1, 5, and 6 was carried out. Compounds 1 and 5 showed the different conformations from those reported. 相似文献
82.
Michinori Akaiwa Hiroki Fukumoto Takakazu Yamamoto 《Journal of organometallic chemistry》2005,690(18):4192-4196
Thioamide-based tridentate ligands, 1,3-benzenedicarbothioamides (1a-c), were used to afford pincer palladium(II) complexes (Pd(1-H)Cl, 2a-c) with η3-S,C,S type coordination. The complexes exhibit strong emission in a glassy frozen state as well as in the solid state. The decay lifetime of the emission from the complexes is in a range of 8-9 × 10−5 s, which is indicative of phosphorescent emission. 相似文献
83.
Takiguchi Yu Seo Min-Woong Kagawa Keiichiro Takamoto Hisayoshi Inoue Takashi Kawahito Shoji Terakawa Susumu 《Optical Review》2016,23(2):364-368
Optical Review - We propose a novel full-electronically controlled laser confocal microscope in which a liquid-crystal-on-silicon spatial light modulator and a custom CMOS imaging sensor are... 相似文献
84.
Katsuhiro Shirono Kosei Iwase Hiroshi Okazaki Masaru Yamazawa Kazuhiro Shikakume Natsuo Fukumoto Masashi Murakami Masaaki Yanagisawa Takahisa Tsugoshi 《Accreditation and quality assurance》2013,18(3):161-174
Methods of utilizing the Youden plot obtained from interlaboratory comparison tests are proposed. The Youden plot is a powerful tool for visually evaluating between- or within-laboratory errors. However, there are no generally applicable methods to indicate the anomalies in the between- and the within-laboratory errors in qualitative terms. An evaluation frame was therefore developed in this study as an indication method. Moreover, the Youden plot is considered to be useful for visually assessing the comprehensive performance of laboratories using two types of results. Although the confidence ellipse has been proposed in ISO 13528:2005 for this purpose, robust determination of the parameters has not yet been implemented. In the present study, robust determination of one of the parameters, the correlation coefficient, was developed. Our proposals were analytically validated using two types of statistical models. In addition, the properties were evaluated through computational simulations. From the results obtained, it can be concluded that our proposals are practically applicable to actual interlaboratory comparison tests. 相似文献
85.
86.
Masaru Tomita Yusuke Fukumoto Kenji Suzuki Yukikazu Iwasa 《Physica C: Superconductivity and its Applications》2010
Large single-grain bulk RE–Ba–Cu–O (RE: rare earth elements) superconductors can trap large fields exceeding several teslas and thus can function as very strong quasi-permanent magnets. We have found that the resin can penetrate into a bulk superconductor, when the sample was immersed in molten resin. Hence, resin impregnation was effective in improving mechanical properties. Three bulk superconductors‘ annuli with resin impregnation, each 50-mm i.d. and 80-mm o.d. was built and energized, by a field-cool method, to generate, in a bath of liquid nitrogen, a persistent trapped field of 1.62 T. 相似文献
87.
The reaction of internal alkynes 1 with CO and pyridin-2-ylmethanol (2) in the presence of Rh(4)(CO)(12) results in a double-hydroesterification leading to 1,4-dicarboxylate esters 3. The reaction does not proceed via two consecutive hydroesterifications of alkynes, but the intermediacy of ketene intermediates is proposed. The coordination of the pyridine nitrogen in 2 to rhodium is essential for the reaction to proceed. [reaction: see text] 相似文献
88.
Ueshima K Takahashi KA Fujioka M Arai Y Horii M Asano T Hirata T Suehara H Tanaka T Kubo T 《Magnetic resonance imaging》2006,24(5):645-650
OBJECTIVE: The aim of this study was to investigate the relationship between abnormal acetabular labrum depicted by radial magnetic resonance and progressive joint space narrowing (JSN) of hip dysplasia. METHODS: Subjects were 23 joints [21 patients; mean age: 35.1 years (16-53 years)] that had acetabular dysplasia with lateral center-edge angle of Wiberg (CE angle) greater than 5 degrees and smaller than 25 degrees (mean, 16.4 degrees ), which did not show any arthrotic changes on plain radiograms and were followed up for 3 years or longer. Radial images of acetabular labrum were classified into three stages. RESULTS: Progression of JSN was not significantly related to CE angle but to progression of MRI stage (P=.006). In multivariate analysis, one rank progression of MRI stage was significantly associated with progression of JSN (adjusted OR=11.41, 95% CI: 1.51-86.24, P=.018). CONCLUSION: Our findings showed that in patients whose acetabular dysplasia has 5-25 degrees CE angle, MRI staging based on radial MRI is a better factor for prediction of progression of JSN than CE angle. 相似文献
89.
Horiuchi M Tokuda H Ohnishi K Yamashita M Nishino H Maoka T 《Natural product research》2006,20(2):161-166
To search for possible cancer chemopreventive agents from natural sources, we performed primary screening of metabolites of Alternaria porri by examining their possible inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. The ethyl acetate extract of A. porri showed the inhibitory effect on EBV-EA activation. Three porritoxins (1-3) were obtained as inhibitory active compounds for EBV-EA from ethyl acetate extract. 6-(3',3'-Dimethylallyloxy)-4-methoxy-5-methylphthalide (2) showed the strongest activity among them. Inhibitory effect of porritoxin (1) and (2) was superior to that of beta-carotene, a well-known anti-tumor promoter. Furthermore, the structure-activity correlation of porritoxins and their related compounds were discussed. 相似文献
90.
Keiichiro Hozumi Keisuke Kitamura Tatsuya Kitade Shozo Iwagami 《Microchemical Journal》1983,28(2):215-226
Glass particles derived from the cutting of glass ampoules and suspended in parenteral solutions were introduced into mouse organs by intravenous injections in the tail vein. Organs were removed, thin sectioned, and plasma ashed on glass slides by means of glow-discharged oxygen to remove organic matrices which interfered with microscopic observation of glass particles. The ashed specimens were subsequently coated with a thin film of plasma-polymerized tetrafluoroethylene which suppressed the hygroscopicity of the specimens so that they became hydrophobic and at the same time permanently preserved the microstructures of the ashed specimens. Microscopic investigation of the glass particles retained in the ashed specimens supported size-dependent localization of the glass particles in different organs; i.e., large particles over 20 μm in diameter were mostly retained in the lung, while smaller particles around 5–10 μm in diameter were found in the liver and spleen, and occasionally in the kidney. A mesh-screen effect was therefore supposed along the route of blood circulation. No glass particle was found in the brain. Large numbers of extremely small glass particles less than 5 μm in diameter were not accounted for in all the organs investigated, but a wide diffusion in the whole body at very low density was presumed. 相似文献