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951.
952.
Brown CN Cooper WE Finley D Hsiung YB Jonckheere AM Jostlein H Kaplan DM Lederman LM Moreno G Hemmi Y Imai K Miyake K Nakamura T Sasao N Tamura N Yoshida T Maki A Sakai Y Gray R Luk KB Rutherfoord JP Straub PB Williams RW Young KK Adams MR Glass H Jaffe D McCarthy RL Crittenden JA Smith SR 《Physical review letters》1989,63(24):2637-2640
953.
K. Tanaka T. Takeda M. Nakamura S. Yamamura K. Miyajima 《Colloid and polymer science》1989,267(6):520-524
Interactions of the mixed surfactant solution of dodecylamido propyl dimethyl aminoacetate and sodium dodecyl sulfate with the liposomal membrane were studied. Lytic activities of the surfactants were measured as a function of the concentrations of surfactant and phospholipid and the composition of mixed surfactants. The solubilization limits of phospholipid by surfactants were determined from the change of their aggregation behavior in suspensions at equilibrium by means of quasi-elastic light scattering. The mixed surfactant solutions showed lower lytic activity than single component surfactant solution in spite of the strong adsorption onto the liposome surface. This was attributed to low solubilization power of binary mixture for phospholipid. 相似文献
954.
Junji Furukawa Eiichi Kobayashi Takahiro Kawagoe 《Journal of polymer science. Part A, Polymer chemistry》1978,16(7):1609-1625
Copolymerization of acetylenic monomers and 1,3-dienes was carried out by use of nickel naphthenate–diethylaluminum chloride catalyst. The molecular weight of the copolymers is rather low, and the copolymers are suitable as prepared for direct use as coating vehicles. In the system of acetylene and 1,3-dienes, the order of the copolymerization rate decreases in the following order: butadiene > isoprene > 2,3-dimethylbutadiene > chloroprene. 1,3-Dienes substituted at 1-and/or 4-position were scarcely copolymerized with acetylene. Methylacetylene and dienes tend to form cyclized copolymers. In the system of phenylacetylene and dienes, polyphenylacetylene was the main product; the copolymer was not obtained. The copolymer composition and the sequence distribution of linear copolymers were evaluated by 1H-NMR spectra. Comparison of dyad fractions of copolymers evaluated from NMR spectra and those calculated by assuming random polymerization indicated that the copolymers of acetylene and dienes were random, and that the copolymers of methylacetylene and dienes were somewhat blocky. The coordination of monomers on the catalyst may play an important role in controlling the copolymerizability. 相似文献
955.
The pH response of a pH-sensitive field-effect transistor (FET) is not affected by a ca. 1-μm thick membrane formed from λ-aminopropyltriethoxysilane and glutaraldehyde over the gate insular by a vapor deposition method. The response between pH 5.5 and 8.5 is ca. 61 mV pH?1 at 37°C in 5 mM Tris-HCl buffer. When urease is immobilized on the membrane, the sensor gives a linear relationship between the initial rate of the output gate voltage change and the logarithmic value of urea concentration between 16.7 and 167 mM. Determination of urea is possible within 30 s. The optimum pH is 6.0–6.5, at 37°C. The system can be used for 20 days with only slight loss of enzymatic activity. 相似文献
956.
Kamiya S Shirahase H Yoshimi A Nakamura S Kanda M Matsui H Kasai M Takahashi K Kurahashi K 《Chemical & pharmaceutical bulletin》2000,48(6):817-827
We synthesized a series of indoline derivatives with an amide or urea moiety and examined their inhibitory effects on acyl-CoA:cholesterol acyltransferase (ACAT) activity, lipid-peroxidation and serum cholesterol levels in experimental animals. Among the derivatives synthesized, a series of N-(1-alkyl-4,6-dimethylindolin-7-yl)-2,2-dimethylpropanamides++ + potently inhibited rabbit intestinal ACAT activity and lipid-peroxidation of rat brain homogenate. The effect on ACAT activity was related to the length of the alkyl chain at the 1-position of indoline. N-(4,6-Dimethyl-1-octylindolindolin-7-yl)-2,2-dimethylpropanami de hydrochloride (55) showed inhibitory effects on intestinal and hepatic ACAT activity slightly weaker than those of YM-750, and an inhibitory effect on low density lipoprotein (LDL)-peroxidation similar to that of probucol. Compound 55 also reduced serum cholesterol at 10 mg/kg/d in hyperlipidemic rats and 20 mg/kg/d in normolipidemic hamsters. The plasma concentration of 55 reached 716 ng/ml in dogs (10 mg/kg, p.o.), which is an effective concentration against hepatic ACAT activity and LDL-peroxidation. In conclusion, compound 55 is a novel bioavailable ACAT inhibitor with anti-peroxidative activity and is thus a promising anti-atherosclerotic and anti-hyperlipidemic drug. Indoline proved to be a useful pharmacophore for molecular design of new anti-peroxidative drugs. 相似文献
957.
Tadashi Hasegawa Fuki Nakamura Jun-Ichi Moribe Michikazu Yoshioka 《Journal of heterocyclic chemistry》1987,24(3):829-831
3-Phenylpyrroles 2 were easily prepared in good yields by hydride reduction of 4-hydroxypyrrolidin-2-ones 1 , which have been prepared in high yields from the photoreaction of N,N-dialkylbenzoylacetamides, with lithium aluminum hydride. 相似文献
958.
Akutagawa T Takeda S Hasegawa T Nakamura T 《Journal of the American Chemical Society》2004,126(1):291-294
One-dimensional dielectric (N.H.N)( infinity ) hydrogen-bonding chains of monoprotonated 1,4-diazabicyclo[2.2.2]octane (HDABCO(+)) were introduced into an electrically conducting 7,7,8,8-tetracyano-p-quinodimethane (TCNQ) salt as the countercation structure. Room-temperature electrical conductivity was approximately 10(-)(3) S cm(-)(1), with a semiconductive behavior. The temperature-dependent dielectric constants of (HDABCO(+))(2)(TCNQ)(3) indicated a dielectric transition at 306 K. A large deuterium isotope effect for the dielectric transition (DeltaT = 70 K) was observed for the deuterated salt, (DDABCO(+))(2)(TCNQ)(3). Thermally activated order/disorder of the protons or deuteriums within the one-dimensional hydrogen-bonding chains of (HDABCO(+))( infinity ) and (DDABCO(+))( infinity ) affected the dielectric responses in the TCNQ-based semiconductors. 相似文献
959.
Toshinobu Yogo Koichi Kikuta Kazuo Niwa Masao Ichida Arao Nakamura Shin-ichi Hirano 《Journal of Sol-Gel Science and Technology》1997,9(2):201-209
β-BaB2O4 (β-BBO) thin films were successfully synthesized by the sol-gel method using metallo-organic compounds. A stable BBO precursor
solution was prepared from barium metal and boron triethoxide or 2,4,6-triethoxycyclotriboroxane in a mixture solvent of ethanol
and 2-ethoxyethanol. As-precipitated powder formed by hydrolysis of the precursor solutions crystallized to ψ phase, which
was transformed to β phase at higher temperatures. The transformation temperatures of powders from ψ to β phase of the ethoxide
system and the boroxane system were 600 and 680°C, respectively. The calcination of precursor films in a mixture gas of water
and oxygen was found to decrease the crystallization temperature of β-BBO films on Pt sheet substrates. The precursor films
prepared from the ethoxide system and the boroxane system crystallized to β-BBO on Pt (111)/glass substrates at 500 and 550°C,
respectively. The BBO films on Pt(111)/glass substrates showed the strong (006) preferred orientation. The β-BBO films on
Pt(111)/glass substrates showed the second harmonic generation (SHG) of the 532 nm light on irradiation with 1064 nm light.
The SH power from the BBO films was correlated with the fundamental power through the square-law proportionality based on
the theory. The SHG efficiency of the BBO films was dependent upon the film thickness. 相似文献
960.
Kaoru Nakamura Masayuki Fujii Atsuyoshi Ohno Shinzaburo Oka 《Tetrahedron letters》1984,25(36):3983-3986
Olefinic double bonds in α,β-unsaturated carbonyl or nitro compounds are reduced chemoselectively by Hantzsch ester on silica gel in excellent yields. 相似文献