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41.
Sato S Komoto T Kanamaru Y Kawamoto N Okada T Kaiho T Mogi K Morimoto S Umehara N Koda T Miyashita A Sakamoto T Niino Y Oka T 《Chemical & pharmaceutical bulletin》2002,50(2):292-297
New muq-opioid receptor (MOR) agonists containing 4-hydroxypiperidine, piperidine and piperazine moieties were synthesized and evaluated to find a peripheral opioid analgesic. Among the synthesized compounds, 12-[1-[3-(N,N-dimethylcarbamoyl)-3,3-diphenylpropyl]-4-hydroxypiperidin-4-yl]phenoxy]acetic acid (8: SS620) having phenoxyacetic acid and 4-hydroxypiperidine moieties showed the highest agonist potency on the MOR in an isolated guinea-pig ileum preparation, and it also had selectivity to the human MOR expressed in Chinese hamster ovary (CHO)-K1 cells compared with the same types of delta- and kappa-opioid receptors (DOR and KOR). In addition, compound 8 showed a 10 times more potent MOR agonist activity than loperamide. Furthermore, compound 8 showed a peripheral analgesic activity in vivo screening on rat. 相似文献
42.
43.
Photolysis of tris(trimethylsilyl)phenylsilane, in alcohols yielded 1-aikoxy-1-phenyl-2, 2,2-trimethyldisilane, dialkoxyphenylsilane, hexamethyldistlane, and trimethylstlane as major products. The formation of the products was explained by a mechanssm which included the consecutive generatinn of phenyltrimethylsilylsilyleses and alkoxyphenylsilylenes. 相似文献
44.
45.
H.?IidaEmail author M.?Oka H.?Suganuma 《The European Physical Journal A - Hadrons and Nuclei》2005,23(2):305-315
Dynamical chiral-symmetry breaking (DCSB) in QCD is investigated in the Schwinger-Dyson (SD) formalism based on lattice QCD data. From the quenched lattice data for the quark propagator in the Landau gauge, we extract the SD integral kernel function, the product of the quark-gluon vertex and the polarization factor in the gluon propagator, in an Ansatz-independent manner. We find that the SD kernel function exhibits the characteristic behavior of nonperturbative physics, such as infrared vanishing and strong enhancement at the intermediate-energy region around p 0.6GeV. The infrared and intermediate energy region (0.4GeV < p < 1.5GeV) is found to be most relevant for DCSB from analysis on the relation between the SD kernel and the quark mass function. We apply the lattice-QCD-based SD equation to thermal QCD, and calculate the quark mass function at the finite temperature. Spontaneously broken chiral symmetry is found to be restored at high temperature above 110 MeV. 相似文献
46.
Mott's metal-insulator transition at an interface due to band bending is studied by the density matrix renormalization group approach. We show that the result can be recovered by a simple modification of the conventional Poisson's equation approach used in semiconductor heterojunctions. A novel mechanism of colossal electroresistance is proposed, which incorporates the hysteretic behavior of the transition in higher dimensions. 相似文献
47.
Oka H Ito Y Ikai Y Matsumoto H Kato K Yamamoto I Shimizu M Kawamura N Miyazaki Y Nojiri T Okumura M Ohmi S Sato T Mori G 《Journal of AOAC International》2001,84(2):350-353
A survey was conducted to determine the incidence of tetracycline antibiotic (TCAs) residues in the kidneys of slaughtered animals that did not pass inspection for human consumption by the Japanese Food Sanitation Law and the Meat Inspection Law at the slaughterhouses in Aichi Prefecture, Japan, from April 1985 to March 1998. The kidneys were analyzed by the AOAC Official Method 995.09. Among 424 animals (147 cattle and 277 pigs), 131 (30.9%) were contaminated with TCAs, including 69 (16.3%) with chlortetracycline (CTC), 61 (14.4%) with oxytetracycline (OTC), 3 (0.7%) with tetracycline (TC), and 1 (0.2%) with doxycycline (DC). One sample (cattle kidney) was contaminated with both OTC and DC. The frequencies of OTC and TC residues were significantly higher (p < 0.05) in cattle than in pigs, whereas, the frequency of CTC was significantly higher (p < 0.01) in pigs. Pig kidney samples collected in 1991-1997 had significantly higher incidences of TCAs and CTC (p < 0.01) residues than those in 1985-1986. 相似文献
48.
Ida K Funaba H Kado S Narihara K Tanaka K Takeiri Y Nakamura Y Ohyabu N Yamazaki K Yokoyama M Murakami S Ashikawa N deVries PC Emoto M Goto M Idei H Ikeda K Inagaki S Inoue N Isobe M Itoh K Kaneko O Kawahata K Khlopenkov K Komori A Kubo S Kumazawa R Liang Y Masuzaki S Minami T Miyazawa J Morisaki T Morita S Mutoh T Muto S Nagayama Y Nakanishi H Nishimura K Noda N Notake T Kobuchi T Ohdachi S Ohkubo K Oka Y Osakabe M Ozaki T Pavlichenko RO Peterson BJ Sagara A Saito K Sakakibara S Sakamoto R 《Physical review letters》2001,86(23):5297-5300
Recent large helical device experiments revealed that the transition from ion root to electron root occurred for the first time in neutral-beam-heated discharges, where no nonthermal electrons exist. The measured values of the radial electric field were found to be in qualitative agreement with those estimated by neoclassical theory. A clear reduction of ion thermal diffusivity was observed after the mode transition from ion root to electron root as predicted by neoclassical theory when the neoclassical ion loss is more dominant than the anomalous ion loss. 相似文献
49.
Narihara K Watanabe KY Yamada I Morisaki T Tanaka K Sakakibara S Ida K Sakamoto R Ohyabu N Ashikawa N Emoto M Funaba H Goto M Hayashi H Idei H Ikeda K Inagaki S Inoue N Kaneko O Kawahata K Kobuchi T Komori A Kubo S Kumazawa R Masuzaki S Miyazawa J Morita S Motojima O Murakami S Muto S Mutoh T Nagayama Y Nakamura Y Nakanishi H Nishimura K Noda N Notake T Ohdachi S Oka Y Ohkubo K Osakabe M Ozaki S Peterson BJ Sagara A Saito K Sasao H Sasao M Sato K Sato M Seki T Shimozuma T Shoji C Sudo S 《Physical review letters》2001,87(13):135002
It was observed that the vacuum magnetic island produced by an external error magnetic field in the large helical device shrank in the presence of plasma. This was evidenced by the disappearance of flat regions in the electron temperature profile obtained by Thomson scattering. This island behavior depended on the magnetic configuration in which the plasmas were produced. 相似文献
50.
Toshinobu Kanai Hiroki Ishibashi. Yoshikazu Hayashi Kunio Oka Takaaki Dohmaru Tatsuo Ogawa Shoji Furukawa Robert West 《Journal of Polymer Science.Polymer Physics》2001,39(11):1085-1092
The thermochromic behavior of poly(di‐n‐octylsilane) {[Si(C8H17)2]n; PDOS} was studied by ultraviolet (UV) absorption, differential scanning calorimetry, and X‐ray diffraction measurements. The structure of PDOS in the low‐temperature phase strongly depended on not only the temperature but also the rate of cooling, that is, the thermal history. Temperature‐dependent UV absorption spectra were highly dependent on thermal hysteresis. Cooled rapidly (10 K/min), PDOS showed two absorption peaks at 3.32 and 3.51 eV in low‐temperature‐ordered phases, whereas a single absorption peak at 3.32 eV became predominant with slow cooling (0.3 K/min). The appearance of the two peaks at low temperatures suggested that a mixture of different conformations was introduced by rapid cooling. A fiber diffraction pattern measured at 240 K after rapid cooling also showed evidence of the existence of novel conformation. A temperature‐dependent powder X‐ray diffraction pattern changed significantly between 270 and 280 K. Rapid cooling reduced the intensity of the X‐ray diffraction peak in this temperature region. This intensity change was explained by the conformational mixture in the polymer. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 1085–1092, 2001 相似文献