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101.
H Li T Miyahara Y Tezuka T Namba N Nemoto S Tonami H Seto T Tada S Kadota 《Canadian Metallurgical Quarterly》1998,21(12):1322-1326
Four water extracts of Kampo formulae (Yi-kkan-sen, Dai-ho-in-gan, Ni-chi-gan, Tsu-kan-gan) were screened for their inhibitory activities on bone resorption induced by parathyroid hormone (PTH) in organ culture using neonatal mouse parietal bones. Among the Kampo formulae, Tsu-kan-gan (TKG) showed the most potent inhibitory activity. We further fractionated the TKG water extract by monitoring the inhibitory activity on bone resorption stimulated by PTH in vitro. The MeOH fraction of the water extract inhibited PTH-stimulated bone resorption, and its inhibitory activity was more potent than those of other fractions. The MeOH fraction was then subjected to Sephadex LH-20 column chromatography to give fractions I, II and III, which were examined for bone resorption activity. Fraction I inhibited PTH-stimulated bone resorption, and its inhibitory activity was more potent than those of the other fractions. Upon oral administration of the three fractions (100 mg/kg/d) to ovariectomized (OVX) mice, fractions I and III prevented the decrease of bone mineral density (BMD) of the lumbar vertebra. Eleven compounds isolated from the MeOH fraction were examined for their inhibitory effect on PTH-stimulated bone resorption. Among them, berberine (1), syringin (3), limonin (4) and mangiferin (10) showed a significant inhibitory effect on bone resorption. In the formation assay of osteoclast-like cells, these compounds decreased the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNCs). The inhibitory effect of TKG on bone resorption may be at least partly due to the inhibitory action of these compounds. 相似文献
102.
H Nakajima I Yoshiuchi T Hamaguchi K Tomita T Yamasaki K Iizuka K Okita M Moriwaki A Ono T Oue Y Horikawa R Shingu J Miyagawa M Namba T Hanafusa Y Matsuzawa 《Canadian Metallurgical Quarterly》1996,94(3):327-330
OBJECTIVE: To assess the effect of pregnancy, maternal position, and cardiac output on intrapulmonary shunting (Qs/Qt) in normotensive nulliparous women near term. METHODS: Ten normotensive nulliparas between 36 and 38 weeks' gestation underwent pulmonary artery catheterization (via the subclavian route) and radial artery canalization. Baseline assessments were made with subjects in the left lateral recumbent position after a 30-minute stabilization period. Measurements were obtained sequentially in the left lateral, right lateral, supine, knee-chest, sitting, and standing positions. Each position change was followed by a 10-minute pre-measurement stabilization period. Cardiac output was measured via the thermodilution technique. Blood samples were obtained simultaneously from the pulmonary and radial arteries and analyzed in duplicate for oxygen content with a blood gas analyzer. Qs/Qt was calculated using the classic shunt equation. Statistical analysis was performed by analysis of variance of repeated measures of Qs/Qt and maternal position. The relationship of Qs/Qt to maternal cardiac output was evaluated by the correlation coefficient. Significance was defined as P < .05. RESULTS: Directly measured Qs/Qt averaged 15.3% in left lateral, 15.2% in right lateral, 13.9% in supine, 12.8% in knee-chest, 13.8% in sitting, and 13.0% in standing positions. There was no statistically significant correlation between Qs/Qt and cardiac output (R2 = 0.11, not significant). CONCLUSION: This is the first report of directly measured Qs/Qt in normal pregnant women in the third trimester. Qs/Qt values reported in pregnancy are higher than those reported in nonpregnant individuals. 相似文献
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106.
Detection of microbial cells by cyclic voltammetry 总被引:4,自引:0,他引:4
107.
Okajima T Tamura K Ogasaka Y Haga K Takahashi S Ichimaru S Kito H Fukuda S Goto A Nomoto K Satake H Kato S Kamata Y Furuzawa A Akimoto F Yoshioka T Kondo K Haba Y Tanaka T Wada K Hamada N Hudaverdi M Tawara Y Yamashita K Serlemitsos PJ Soong Y Chan KW Owens SM Berendse FB Tueller J Misaki K Shibata R Mori H Itoh K Kunieda H Namba Y 《Applied optics》2002,41(25):5417-5426
A hard-x-ray telescope is successfully produced for balloon observations by making use of depth-graded multilayers, or so-called supermirrors, with platinum-carbon (Pt/C) layer pairs. It consists of four quadrant units assembled in an optical configuration with a diameter of 40 cm and a focal length of 8 m. Each quadrant is made of 510 pieces of coaxially and confocally aligned supermirrors that significantly enhance the sensitivity in an energy range of 20-40 keV. The configuration of the telescope is similar to the x-ray telescope onboard Astro-E, but with a longer focal length. The reflectivity of supermirrors is of the order of 40% in the energy range concerned at a grazing angle of 0.2 deg. The effective area of a fully assembled telescope is 50 cm2 at 30 keV. The angular resolution is 2.37 arc min at half-power diameter 8.0 keV. The field of view is 12.6 arc min in the hard-x-ray region, depending somewhat on x-ray energies. We discuss these characteristics, taking into account the figure errors of reflectors and their optical alignment in the telescope assembly. This hard-x-ray telescope is unanimously afforded in the International Focusing Optics Collaboration for muCrab Sensitivity balloon experiment. 相似文献
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109.
Kawachi T Kado M Tanaka M Hasegawa N Nagashima K Sukegawa K Lu P Takahashi K Namba S Koike M Nagashima A Kato Y 《Applied optics》2003,42(12):2198-2205
A two-beam chirped-pulse-amplification Nd:glass laser system dedicated to x-ray laser research is described. Each beam provides an output energy of 20 J with a typical pulse duration of 1.3 ps. A prepulse of variable duration is generated by use of a novel, to our knowledge, optical system. A reflection optical system, comprised of an off-axis parabolic mirror and a spherical mirror, produces a line focus with 6-mm length and 165-microm width without chromatic aberration. By use of this pumping laser system, the nickel-like silver x-ray laser at a wavelength of 13.9 nm has been demonstrated. 相似文献
110.
Time duration of the output pulse of electron-beam-pumped CdS laser was investigated. It increased with increase of the excitation current density and was of the order of 100 ns at the beam voltage of 25 kV. It was shown experimentally that the quenching of the laser oscillation is due to the rise of the threshold current density as the result of the temperature rise in the active region of the crystal. The expression for the duration of laser oscillation based on this model was derived and compared with the experimental results. The dependence of the duration on the excitation current density was explained by this model. 相似文献