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121.
122.
Y Kohno Y Hiraki Y Takeda S Awai K Murakami T Noriyasu M Yamamoto K Aono Y Nakata 《Radioisotopes》1988,37(6):325-329
Xenon-133 ventilation study were used to measure regional ventilation in seven patients with pulmonary sarcoidosis and in four normal subjects. For the purpose of analyzing the washout curves on the whole lungs, two ventilation indexes were calculated, which were TA/H and T1/2. TA/H is that the area under the curve divided by the difference in mean count rate during equilibrium and at 120 s after washout started. T1/2 value represents the time required to 50% of the mean count rate during equilibrium. The average time of TA/H on the whole lung was 13.5 +/- 1.1 s in normal subjects (n = 4), 13.0 +/- 4.3 s in stage I (bilateral hilar lymphadenopathy without lung involvement on chest X-ray) sarcoidosis (n = 3), 21.3 +/- 1.8 s in stages I, II (lung involvement) sarcoidosis (n = 4). The average time of T1/2 on the whole lung was 43.7 +/- 4.7 s in normal subjects, 42.3 +/- 16.0 s in stagel sarcoidosis, 72.5 +/- 28.6 s stages II, III sarcoidosis. The ventilation indexes on the regional lungs showed almost a similar tendency to that on the whole lung. The ventilation indexes in patients with stage II, III sarcoidosis were significantly longer than in normal subjects and in patients with stage I sarcoidosis. It was suggested that 133Xe washout test might detect regional ventilation abnormalities which were not recognized on chest X-ray in pulmonary sarcoidosis. 相似文献
123.
S. Suzuki M. Kohno H. Shiromaru Y. Achiba H. Kietzmann B. Kessler G. Ganteför W. Eberhardt 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):407-409
Mass spectra of LaC n - were taken by using a laser-vaporization source (LVS) and pulsed arc cluster ion source (PACIS) applied to La-carbon composite rods (1:130 atomic ratio). The mass spectrum using the LVS with annealing procedure has shown several magic numbers for LaC n - (n = 44, 50, 60, and 70), whereas only small LaC n - (up to n = 14) have been observed in the mass spectrum using the PACIS. Photoelectron spectra of some of these have been measured using a magnetic-bottle type time-of-flight electron spectrometer. These results indicate the exsistence of a few conformational isomers for small La-containing carbon cluster negative ions LaC n - (n = 5–8). 相似文献
124.
Cell electrophoretic mobility (EPM) can be used to characterize individual cells. The purpose of this study is to establish reproducible and reliable cell EPM values obtained using microcapillary electrophoresis (microCE) chips. We studied cell electrophoresis on microCE chips through the comprehensive measurement of EPM and zeta potential. The inner wall of microchannels in microCE chips was coated with three kinds of reagents, namely bovine serum albumin (BSA), gelatin, and 2-methacryloyloxyethylphosphorylcholine (MPC) polymer to prevent nonspecific adhesion and interaction between cells and the inner wall. Electrophoresis was conducted in phosphate-buffered saline (pH 4-9) using erythrocytes extracted from sheep whole blood. Electroosmotic flow (EOF) mobility was measured using noncharged particles, and then the true EPM was calculated by subtracting the EOF mobility from the electromigration. MPC polymer coatings in microCE chips reduced the zeta potential of the inner wall and fully prevented nonspecific adhesion. EPM data obtained using microCE chips were almost the same and reproducible over a wide range of pH irrespective of the coating reagent used. In conclusion, reliability in the measurement of cell EPM using microCE chips was realized. 相似文献
125.
126.
Hamashima Y Suzuki T Takano H Shimura Y Sodeoka M 《Journal of the American Chemical Society》2005,127(29):10164-10165
We have developed a highly efficient catalytic enantioselective fluorination of oxindole derivatives. In the presence of a catalytic amount of chiral Pd complex 2 (2.5 mol %), various substrates, including aryl- and alkyl-substituted oxindoles, were fluorinated in a highly enantioselective manner (up to 96% ee). In addition, when R was a hydrogen atom, enantioselective fluorination followed by solvolysis gave a monofluorinated ester with up to 93% ee. To our knowledge, this is the first example of catalytic enantioselective fluorination of oxindoles. 相似文献
127.
Masao Onda Motoo Asai Toshiya Kohno Yasuhiro Kikuchi Ichiro Yamaguchi 《Journal of Molecular Structure》1987,162(3-4):183-189
The microwave spectrum of benzoyl chloride was observed in the frequency range 12–18.6 GHz. Rotational constants have been obtained for the ground vibrational state, the first three excited torsional states of the COCl group, and one of the out-of-plane bending states. The residual inertial defect obtained from the ground and the torsional excited states indicates that the equilibrium conformation is planar. Ab initio MO calculations (STO-3G) showed the potential energy curve as a function of the COCl torsional angle to be rather flat around zero degrees. 相似文献
128.
129.
130.
Yuta Yokoyama Tsuyoshi Hori Ryuta Okada Daiki Harimoto Chihiro Sugawara Yoichi Yamada Masahiro Sasaki 《Surface science》2009,603(18):2845-2848
Effects of the translational energy of incident oxygen molecules on surface processes from dissociative adsorption to subsequent associative desorption on Pt(1 1 1) have been investigated by means of supersonic molecular beam scattering. The reaction rate of associative desorption increases with the incident translational energy. The enhanced associative desorption can be attributed to nonthermal diffusion of dissociated oxygen, promoted by the translational energy of incoming molecules. 相似文献