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排序方式: 共有117条查询结果,搜索用时 15 毫秒
101.
102.
Ito T Tanaka T Ido Y Nakaya KI Iinuma M Riswan S 《Chemical & pharmaceutical bulletin》2000,48(7):1001-1005
Two new stilbene glucosides [(+)-alpha-viniferin 13b-O-beta-glucopyranoside and resveratrol 12-C-beta-glucopyranoside] and two new resveratrol oligomers, hemsleyanols A and B, were isolated from the bark of Shorea hemsleyana along with four known resveratrol oligomers. The structures of the isolates, including the relative configurations, were established by spectroscopic data involving long-range coupling and nuclear Overhauser effect experiments. 相似文献
103.
Miyuki Furusawa Yoshimi Ido Toshiyuki Tanaka Tetsuro Ito Ken‐ichi Nakaya Iliya Ibrahim Masayoshi Ohyama Munekazu Iinuma Yoshiaki Shirataka Yoshikazu Takahashi 《Helvetica chimica acta》2005,88(5):1048-1058
One new flavanone, 4′‐hydroxyisorottlerin ( 2 ), and two new chalcone derivatives, kamalachalcones C ( 3 ) and D ( 4 ), were isolated from Mallotus philippensis (kamala tree). The largest compound ( 4 ; Mr 1098 g/mol) was shown to possess a unique, fused‐ring system made of two hydroxy‐chalcone units, giving rise to eight fused benzene/pyran units. From the same plant, the following six known compounds were also isolated: kamalachalcone A ( 5 ) and B ( 6 ), isoallorottlerin ( 7 ), isorottlerin ( 8 ), 5,7‐dihydroxy‐8‐methyl‐6‐prenylflavanone ( 9 ); 6,6‐dimethylpyrano(2″,3″: 7,6)‐5‐hydroxy‐8‐methylflavanone ( 10 ), and rottlerin ( 1 ). The structures of the new compounds were confirmed by in‐depth spectral analyses, including 2D‐NMR techniques, and the full 13C‐NMR assignments of the known flavanones 1 and 7 – 10 are published for the first time. 相似文献
104.
A thermodynamic model has been developed for the system As–Fe by combining the Calphad approach and the first-principles total energy calculations. Our first-principles calculations are based on the projector augmented wave method within the generalized gradient approximation. We performed these calculations because the experimental values for the enthalpy of formation of the compounds As2Fe, AsFe and AsFe2 may have a large uncertainty. Our results indicate significantly more negative values for the enthalpy of formation of these compounds relative to the experimentally established values. We demonstrate that applying our first-principles results in a thermodynamic analysis based on the Calphad approach leads to a calculated phase diagram and thermodynamic properties which are not significantly different from experimental data. 相似文献
105.
Nakanishi T Inatomi Y Murata H Shigeta K Iida N Inada A Murata J Farrera MA Iinuma M Tanaka T Tajima S Oku N 《Chemical & pharmaceutical bulletin》2005,53(2):229-231
A new 4alpha-aryltetralin-type lignan called burseranin (1) and a known analogous lignan picropolygamain (2) were isolated along with known triterpenes, lupeol and epi-lupeol from the methanol extract of stems of Bursera graveolens, which showed a remarkable inhibitory activity against human HT1080 fibrosarcoma cells. The whole structure of 1 was established based on combined spectral studies and the absolute structure for 2 was first confirmed by CD spectral evidence. In addition, cytotoxic activities of the stem (methanol) extract and its components are evaluated in this paper. 相似文献
106.
Hasegawa M Aliu E Andringa S Aoki S Argyriades J Asakura K Ashie R Berns H Bhang H Blondel A Borghi S Bouchez J Burguet-Castell J Casper D Cavata C Cervera A Chen SM Cho KO Choi JH Dore U Espinal X Fechner M Fernandez E Fukuda Y Gomez-Cadenas J Gran R Hara T Hasegawa T Hayashi K Hayato Y Helmer RL Hill J Hiraide K Hosaka J Ichikawa AK Iinuma M Ikeda A Inagaki T Ishida T Ishihara K Ishii T Ishitsuka M Itow Y Iwashita T Jang HI Jeon EJ Jeong IS Joo KK Jover G Jung CK Kajita T Kameda J Kaneyuki K 《Physical review letters》2005,95(25):252301
We report the result from a search for charged-current coherent pion production induced by muon neutrinos with a mean energy of 1.3 GeV. The data are collected with a fully active scintillator detector in the K2K long-baseline neutrino oscillation experiment. No evidence for coherent pion production is observed, and an upper limit of is set on the cross section ratio of coherent pion production to the total charged-current interaction at 90% confidence level. This is the first experimental limit for coherent charged pion production in the energy region of a few GeV. 相似文献
107.
Two new antineoplastic diterpenes from Taxus mairei 总被引:2,自引:0,他引:2
108.
Y Mori K Kawakami K Machida H Oyamada T Matsumoto T Iinuma K Makita Y Okada N Kosaka J Nishikawa 《Radioisotopes》1987,36(9):457-464
The purpose of this study is to evaluate the clinical efficacy of the liver SPECT about detectability of SOLs (space occupying lesion). The images were interpreted with the planar scintigram (PS) only and combination of PS and SPECT (single photon emission computed tomography) by 11 physicians. Changes of false positive and false negative rate were calculated to evaluate the influence of the diffuse parenchymal liver disease and the localization of the SOLs. Addition of SPECT to PS in the cases who are suspected SOLs is effective in right hepatic lobe (right anterior and posterior segment) to detect the SOLs, but not effective in left lateral segment. Addition of SPECT to PS in the cases with diffuse parenchymal liver disease and SOLs increases the false positive rate. 相似文献
109.
Tetsuro Ito Toshiyuki TanakaMunekazu Iinuma Ken-ichi NakayaYoshikazu Takahashi Ryuichi SawaHiroshi Naganawa Veliah Chelladurai 《Tetrahedron》2003,59(8):1255-1264
Two new stilbenoids, vateriaphenols A (1) and B (2), were isolated from the stem bark of Vateria indica along with known 10 stilbenoids (3-12) and bergenin (13). The structures of isolates were established based on spectroscopic analysis. The structures of vateriaphenols A and B were characterized as an octamer and a tetramer of resveratrol, respectively. The spectral properties of the highly condensed vateriaphenol A were also discussed. 相似文献
110.
N Yui Y Akiyama T Matsumoto T Iinuma T Ishikawa T Nakajima K Machida J Nishikawa M Iio K Uno 《Radioisotopes》1988,37(11):608-614
Prospective study of bone scintigraphy was performed on 414 patients with breast carcinoma and 88 patients with prostate carcinoma. In 468 of them, confirmative diagnoses of bone, whether metastasis was existent or not, were made after the observations over a year. Finally, the incidences of bone metastasis were 11 percent for breast carcinoma and 54 percent for prostate carcinoma respectively. The efficacy of preoperative bone scintigraphy in breast carcinoma was comparable to that in prostate carcinoma with regard to improvement of predictive probability of bone metastasis: raising up the probability in the positive cases and bringing down in the negative cases. 相似文献