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排序方式: 共有1735条查询结果,搜索用时 15 毫秒
151.
Yukiko Yasuoka Yuichiro Izumi Takashi Fukuyama Haruki Omiya Truyen D. Pham Hideki Inoue Tomomi Oshima Taiga Yamazaki Takayuki Uematsu Noritada Kobayashi Yoshitaka Shimada Yasushi Nagaba Tetsuro Yamashita Masashi Mukoyama Yuichi Sato Susan M. Wall Jeff M. Sands Noriko Takahashi Katsumasa Kawahara Hiroshi Nonoguchi 《Molecules (Basel, Switzerland)》2022,27(3)
Anemia is a major complication of chronic renal failure. To treat this anemia, prolylhydroxylase domain enzyme (PHD) inhibitors as well as erythropoiesis-stimulating agents (ESAs) have been used. Although PHD inhibitors rapidly stimulate erythropoietin (Epo) production, the precise sites of Epo production following the administration of these drugs have not been identified. We developed a novel method for the detection of the Epo protein that employs deglycosylation-coupled Western blotting. With protein deglycosylation, tissue Epo contents can be quantified over an extremely wide range. Using this method, we examined the effects of the PHD inhibitor, Roxadustat (ROX), and severe hypoxia on Epo production in various tissues in rats. We observed that ROX increased Epo mRNA expression in both the kidneys and liver. However, Epo protein was detected in the kidneys but not in the liver. Epo protein was also detected in the salivary glands, spleen, epididymis and ovaries. However, both PHD inhibitors (ROX) and severe hypoxia increased the Epo protein abundance only in the kidneys. These data show that, while Epo is produced in many tissues, PHD inhibitors as well as severe hypoxia regulate Epo production only in the kidneys. 相似文献
152.
Hirao Shigekazu Kakiuchi Hideki Akata Naofumi Tamari Toshiya Sugihara Shinji Shima Nagayoshi Yokoyama Sumi Tanaka Masahiro 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(7):3077-3083
Journal of Radioanalytical and Nuclear Chemistry - This paper discusses the spatiotemporal variation in atmospheric tritiated water (HTO) concentration near the Fukushima Daiichi Nuclear Power... 相似文献
153.
Araki H Inoue M Suzuki T Yamori T Kohno M Watanabe K Abe H Katoh T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(35):9866-9881
Enantioselective total synthesis of (+)-ottelione A (1) and (-)-ottelione B (2), novel and potent antitumor agents from a freshwater plant, and (+)-3-epi-ottelione A (3), the earlier proposed stereostructure of 1, was efficiently achieved starting from the known tricyclic compound 10. The synthesis involved the following key steps: i) coupling reactions of aldehydes 8 and 9 with the aromatic portion 7 (8+7-->15 and 9+7-->27), ii) base-induced hemiacetal-opening/epimerization reactions of the cyclic hemiacetals 6 and 27 (6-->17 and 27 a-->26 a), and iii) Corey-Winter's reductive olefination of the cyclic thiocarbonates 21 and 36 (21-->22 and 36-->37). The present total synthesis fully established the absolute configuration of these natural products. The cell growth inhibition profile, COMPARE analysis, and tubulin inhibitory assay of (+)-3-epi-ottelione A (3) and its O-acetyl derivative 24 demonstrated that these unnatural substances could be prominent lead compounds for the development of anticancer agents with a novel mode of action. 相似文献
154.
Ali Z. Al-Rubaie Sakae Uemura Hideki Masuda 《Journal of organometallic chemistry》1991,410(3):309-320
A new tellurium-containing heterocyclic compound, 2,2,6,6-tetramethyl-1-oxa-4-tellura-2,6-disilacyclohexane (C6H16OSi2Te) (1), has been prepared by treatment of 1,3-bis(chloromethyl)-1,1,3,3-tetramethyldisiloxane with sodium telluride. Mononuclear and dinuclear palladium complexes of this telluride have been prepared by the reaction of 1 with PdCl2(PhCN)2 and Na2PdCl4, respectively. The following new derivatives of 1 have also been produced: C6H16OSi2TeI2 (2), C6H16OSi2TeBr2, C6H16OSi2TeCl2, C6H16OSi2Te(CH3)I, and C6H16OSi2Te(CH2Ph)Br. IR, 1H and 13C NMR and mass spectral data of these new compounds are reported and discussed. 1H NMR studies revealed that in CDCl3 solution both telluronium salts reductively eliminate alkyl halide. The crystal structure of compound 2 has been determined by X-ray diffraction. The compound crystallizes in the monoclinic space group, P21/c, with four molecules in a unit cell of dimension a 12.960(3), b 8.846(2), c 13.754(4) Å, β 92.44(2)°, R = 0.049, and Rw = 0.067 for 3599 unique reflections with |F0| > 3σ(F0). The compound forms a six-membered ring of a slightly displaced boat type. The geometry about the Te atom is pseudo-octahedral, with two carbon atoms (Te-C = 2.156(7) and 2.137(6) Å) and two iodine atoms of the neighbouring molecules (weak intermolecular bonds, Te · I = 3.769 and 3.806 Å) in the equatorial positions and two iodine atoms (Te-I = 2.909(1) and 2.913(1) Å) in the axial positions. 相似文献
155.
Masayuki Kuzuya Akihiro Noguchi Hideki Ito Shin-Ichi Kondo Nahoko Noda 《Journal of polymer science. Part A, Polymer chemistry》1991,29(1):1-7
Plasma-induced polystyrene radicals were first studied by electron spin resonance (ESR). The room temperature ESR spectrum was compared with those obtained by γ-irradiation, UV-irradiation, and mechanical fracture. It was found that even less than a few seconds of plasma-irradiation gave rise to a large amount of polystyrene radicals and the ESR spectrum consisted of two types of spectra, a triplet and a single broad line. The spectral feature of the triplet was nearly identical with that of γ-irradiated polystyrene. Thus, it was assigned to the structure of a cyclohexadienyl-type radical formed by a nearly random addition of a hydrogen atom to the aromatic ring. The single broad line, thought to be an outline of multicomponent spectrum, was assigned to an immobilized dangling-bond sites at the plasma-induced crosslinked portion of the polystyrene surface. 相似文献
156.
We present an automated conformational analysis program, CAMDAS (Conformational Analyzer with Molecular Dynamics And Sampling). CAMDAS performs molecular dynamics (MD) calculations for a target molecule and samples conformers from the trajectory of the MD. The program then evaluates the similarities between each of the sampled conformers in terms of the root- mean-square deviations of the atomic positions, clusters similar conformers, and finally prints out the clustered conformers. This MD-based conformational analysis is a broadly used method, and CAMDAS is intended to provide a convenient framework for the method. CAMDAS has the ability to find the representative conformers automatically from an arbitrarily given structure of the molecule. The accuracy of the program was examined using N- acetylalanine-N-methylamide, and the obtained result was consistent with that of the systematic search method. In the test calculation of cyclodecane, CAMDAS could identify most of the known conformers and their conformational enantiomers by examining only 5000 conformers. In addition, the potential-scaled method, which we have developed previously as an accelerating technique for MD, could find two additional conformers of cyclodecane that have not been reported. CAMDAS presents a convenient way to find the energetically possible conformers of a molecule, which is needed especially in the early stage of drug design. 相似文献
157.
Hideki Nishimori Masahiro Tatsumisago Tsutomu Minami 《Journal of Sol-Gel Science and Technology》1997,9(1):25-31
Monodispersed silica particles up to ca. 1.2 μm in diameter were prepared by hydrolysis of tetraethoxysilane in the presence
of sodium dodecyl sulfate (SDS). The particle size was increased with an increase of SDS added. The geometrical standard deviation
of the particles was decreased with an increase of SDS. In the earlier reaction stage, double spherical particles by the coalescence
of the particles were frequently observed when large amounts of SDS were added. Particle size was gradually increased after
the coalescence occurred and spherical particles were finally obtained. The results of Nielsen’s chronomal analysis suggest
that the polynuclear layer growth took place after the coalescence of the particles in the presence of larger amount of SDS. 相似文献
158.
Yui Hayashi Noriharu Takada Wahyudiono Hideki Kanda Motonobu Goto 《Plasma Chemistry and Plasma Processing》2017,37(1):125-135
Pulsed discharge plasma is typical oxidation technology for disposing organic compounds in aqueous solutions. When this electrical discharge plasma was applied in water, it may produce hydrogen peroxide (H2O2) without any catalyst or chemical agent. In order to increase H2O2 production by electrical discharge plasma in water, fine bubbles were introduced into the electrical discharge plasma in this experiment. Bipolar pulsed voltages were applied to cylindrical electrodes in the water while Ar or O2 bubbles were introduced, generating a pulsed discharge plasma. The introduction of the bubbles seemed to enhance the dissociation of water molecules and increased H2O2 formation, especially with O2 bubbling. Dissolved oxygen in the water contributed to H2O2 formation by pulsed discharge plasma with the bubbles, while dissociation of water molecules was the cause of H2O2 formation by pulsed discharge plasma without bubbles. More H2O2 was formed by pulsed discharge plasma with O2 bubbles, because the amount of dissolved oxygen in the water increased upon bubbling with O2. 相似文献
159.
Toyoharu Kobayashi Masako Ishida Kazuhiro Imaida Hideki Abe Hisanaka Ito 《Tetrahedron letters》2017,58(33):3294-3295
The stereoselective total synthesis of pleurolactone has been accomplished in 7 steps. The key synthetic features were the construction of four contiguous stereocenters using an endo-selective Diels-Alder reaction and high diastereoselective dihydroxylation. 相似文献
160.
Reaction of 2-propargylphenylcarbamates with diphenyliodonium salts via Meyer-Schuster rearrangement
Hideki Minami Noriko Okamoto Takuya Sueda Takatsugu Sakaguchi Minoru Ishikura Reiko Yanada 《Tetrahedron letters》2017,58(45):4277-4280
The syntheses of 2,3-dihydro-4-quinolones from 2-propargylphenylcarbamates by one-pot tandem process that involves Meyer-Schuster rearrangement or arylative Meyer-Schuster rearrangement/Michael addition of carbamate nitrogen to the resulting vinyl ketones have been developed. Phenylcarbamates tethering tertiary propargyl alcohols underwent arylative Meyer-Schuster rearrangement/Friedel-Crafts alkylation to produce 2,3-dihydroindenones. 相似文献