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161.
In our investigation of a cell proliferation-based screening assay using human ligand-dependent cell lines for medicinal herbal extracts, the acetone extract of the whole plants of Euphorbia lunulata (EL) was observed for its proliferation activity for insulin- and interleukin-10 (IL-10)-dependent cell lines. Fractionation of the active extract led to the isolation of one new flavonoid galactoside, quercetin 3-O-(2',3'-digalloyl)-beta-D-galactopyranoside (1), and four known ones, quercetin 3-O-(2'-galloyl)-beta-D-galactopyranoside (2), hyperin (3), quercetin (4), and gallic acid (5). Compounds 1 and 2 showed insulin-like activity. Compounds 4 and 5 showed IL-10-like activity. This is the first report of these activities of EL, and 1 and 2 will become the seed compounds for the development of a nonpeptidyl insulin substitutional medicine. Compounds 4 and 5 support the pharmacological use of EL, which has been employed as an herbal medicine for the treatment of bronchial asthma. 相似文献
162.
Tadahiro Oh 《Communications in Mathematical Physics》2009,292(1):217-236
We prove the invariance of the mean 0 white noise for the periodic KdV. First, we show that the Besov-type space [^(b)]sp,¥{\widehat{b}^s_{p,\infty}} , sp < −1, contains the support of the white noise. Then, we prove local well-posedness in [^(b)]sp, ¥{\widehat{b}^s_{p, \infty}} for p = 2 + ,
s = -\frac12+{s = -\frac{1}{2}+} such that sp < −1. In establishing the local well-posedness, we use a variant of the Bourgain spaces with a weight. This provides an analytical
proof of the invariance of the white noise under the flow of KdV obtained in Quastel-Valko [21]. 相似文献
163.
164.
165.
Beddo M Burleson G Faucett JA Gardiner S Kyle G Garnett R Grosnick D Hill D Johnson K Lopiano D Ohashi Y Shima T Spinka H Stanek R Underwood D Yokosawa A Glass G Kenefick R Nath S Northcliffe L Jarmer JJ Penttilä S Jeppesen R Tripard G Devereux M Kroll P 《Physical review D: Particles and fields》1994,50(1):104-123
166.
Structures of excited states in 11B are investigated with a method of β – γ constraint antisymmetrized molecular dynamics in combination with the generator coordinate method. Various cluster structures are suggested in excited states. For negative-parity states, we suggest a band with a 2α + t cluster structure. This band starts from the ${3/2^{-}_{3}}$ state and can correspond to the experimental band observed recently. We find that the feature of the ${3/2^{-}_{3}}$ is quite similar to the ${0^{+}_{2}}$ state in 12C. 相似文献
167.
Takeshi Takeda Yasuo Horikawa Tadahiro Nomura Mikako Watanabe Ichiro Miura Tooru Fujiwara 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):391-392
Desulfurizative titanation of allylic sulfides and thioacetals, and the subsequent reactions of resulting organotitanium species were studied. 相似文献
168.
Zymolyase (lyticase) is used for cell wall digestion in yeast experiments and is needed for incubation processes under moderate experimental conditions. This has been thought to cause unfavorable effects, and many researchers are aware that the enzyme method is unsuitable for RNA preparation following several reports of stress responses to the enzyme process. However, RNA preparation with enzyme digestion continues to be used. This may be because there have been insufficient data directly comparing RNA preparation conditions with previous studies. We investigated the influence of enzyme processes in RNA preparation using a DNA microarray, and compared superoxide dismutase (SOD) activities with a non-treated control and the results of previous research. Gene expressions were commonly changed by enzyme processes, and SOD activities increased only during short-term incubation. Meanwhile, both SOD gene expressions and SOD activity during RNA preparation indicated different results than gained under conditions of long-term incubation. These results suggest that zymolyase treatment surely influences gene expressions and enzyme activity, although the effect assumed by previous studies is not necessarily in agreement with that of RNA preparation. 相似文献
169.
Cover Picture: Enantioselective Addition of a 2‐Alkoxycarbonyl‐1,3‐dithiane to Imines Catalyzed by a Bis(guanidino)iminophosphorane Organosuperbase (Angew. Chem. Int. Ed. 52/2015) 下载免费PDF全文
170.
Tadahiro Kato Toshifumi Hirukawa Takaaki Suzuki Masaharu Tanaka Masahiro Hoshikawa Makoto Yagi Motoyuki Tanaka Shin‐suke Takagi Naoko Saito 《Helvetica chimica acta》2001,84(1):47-68
Based on the putative biogenesis of trinervitane‐ and kempane‐type diterpenes (Scheme 1), a biogenetic‐type transformation was simulated by cyclization of 7,16‐secotrinervita‐7,11,15‐triene‐2α,3α,17‐triol ( 23 ) and of its 17‐chloro derivative 30 . The requisite substrates were prepared from geranylgeranoic acid chloride 6 (Schemes 2, 4, and 5). Treatment of 30 with AgClO4 at −20° provided the trinervitantrienediols 32 and 33 in 68 and 5% yields, while kempadienediol 35 was obtained in 50% yield by the same reagent at +20° (Scheme 7). The structures of the cyclization products were elaborated from detailed inspection of NMR spectra including H,H COSY, C,H COSY, and NOESY (Tables 1 and 2). The conformation of 30 and its plausible cyclization intermediate was discussed with the help of physical evidence, including X‐ray crystallographic analysis. 相似文献