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排序方式: 共有316条查询结果,搜索用时 31 毫秒
91.
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93.
Kim H Arakawa H Hatae N Sugimoto Y Matsumoto O Osada T Ichikawa A Ikai A 《Ultramicroscopy》2006,106(8-9):652-662
The distribution of EP3 receptors on a living cell surface was quantitatively studied by atomic force microscopy (AFM). Green fluorescent protein (GFP) was introduced to the extracellular region of the EP3 receptor on a CHO cell. A microbead was used as a probe to ensure certain contact area, whose surface was coated with anti-GFP antibody. The interactions between the antibodies and GFP molecules on the cell surface were recorded to observe the distribution of the receptors. The result indicated that EP3 receptors were distributed on the CHO cell surface not uniformly but in small patches coincident with immunohistochemical observation. Repeated measurements on the same area of cell surface gave confirmation that it was unlikely that the receptors were extracted from the cell membrane during the experiments. The measurement of single molecular interaction between GFP and the anti-GFP antibody was succeeded on the cell surface using compression-free force spectroscopy. The value of separation work required to break a single molecular pair was estimated to be about 1.5 x 10(-18)J. The number of EP3 receptor on the CHO cell surface was estimated using this value to be about 1 x 10(4) under the assumption that the area of the cell surface was about 5,000 microm(2). These results indicated that the number of receptors on a living cell surface could be quantified through the force measurement by the AFM. 相似文献
94.
Power converters have been widely used in many industrial applications. On the ac side of such converters, the current is distorted because of nonlinearity of the power devices even when the source voltage is sinusoidal. This implies that the power converter is regarded as a harmonic-current source. The harmonic current is one of the most important factors in the analysis of converters. This paper analyzes power flow of a power converter that behaves synchronously with the line frequency. Power-flow analysis in a three-phase diode converter with a resistance on the ac side is presented. The analysis is compared with conventional analysis with the assumption that the ratio of the resistance on the ac side to that on the dc side is very small. The proposed power flow concept enables electrical engineers and students to discuss rationally the power flow of a converter. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(1): 70–76, 1997 相似文献
95.
The total lipid and fatty acid compositions of tissues and the stomach contents of three subtropical marine fish species,
subfamily Caesioninae, Caesio diagramma and C. tile, and family Siganidae Siganus canaliculatus, were investigated to clarify the differences between these species. Triacylglycerols (TAG) were the dominant depot lipids
of the three species, whereas wax esters were found as a minor component. In particular, muscle lipids were found to contain
mainly glycerol derivatives such as TAG and phospholipids. The major fatty acids identified in the three species were 16∶0,
18∶0, 18∶1n−9, and 22∶6n−3 (docosahexaenoic acid, DHA). In addition, noticeable levels of 16∶1n−7, 18∶1n−7, 20∶4n−6 (arachidonic
acid, AA), and 20∶5n−3 (eicosapentaenoic acid) were found. DHA was the most abundant polyunsaturated fatty acid (PUFA) in
the muscle and viscera lipids of the three species. The high DHA levels in the lipids of all the organs were found to be higher
than those of the lipid extracted from the stomach contents of the three fishes. In addition, the specimens of S. canaliculatus contained significantly higher levels of AA in its tissues than did the other two species. A high AA content is unusual since
such high levels of n−6 PUFA are rarely found in higher marine organisms. These levels may be due to its characteristic feeding
pattern, because S. canaliculatus prefer and mainly feed on seaweed, which often contains high amounts of n−6 PUFA, such as linoleic acid (18∶2n−6) and AA. 相似文献
96.
Hideaki Itoh Toshiya Uemura Hirofumi Yamaguchi Shigeharu Naka 《Journal of Materials Science》1989,24(10):3549-3552
Epitaxial (Ni, Zn)Fe2O4 films were prepared on (100) MgO single crystal substrate by lowpressure chemical vapour deposition using a thermal decomposition
of acetylacetonatocomplexes, Ni(acac)2, Zn(acac)2 and Fe(acac)3. These complexes were evaporated at 157, 79 and 146° C, respectively, and transported with nitrogen carrier gas (flow rate
100 ml min−1) to the deposition furnace. Polycrystalline and epitaxial films were grown at 500 to 600 and 600 to 650° C, respectively,
under a pressure of 12 torr. The epitaxial film of Ni1−xZnxFe2O4 (x⋍0.4) treated at 600° C for 60 min, showed the saturation magnetization of 67 e.m.u. g−1 and the coercive force of 20 to 30 Oe. 相似文献
97.
98.
Spinal NMDA receptors are involved in hyperalgesia and chronic pain. The activation of spinal NMDA receptor results in the production of nitric oxide in the second order neurons in the spinal cord dorsal horn. We investigated the effects of intrathecally administered nitroglycerin (NTG) which releases nitric oxide in the cell. Formalin test which reflects phasic and tonic nociception was used as a nociceptive measure in rats with chronically implanted intrathecal catheters. Intrathecal injection of NTG resulted in the increase of flinching behavior induced by formalin injection to one paw in phase 1 (phasic) and phase 2 (tonic) responses in a dose-dependent manner. Intrathecally administered NMDA antagonist, MK-801 (MK) dose-dependently inhibited the effect of NTG but the effect was significant only in the phase 2 of the formalin test. MK given after formalin injection had significantly less effect on the phase 2 response. L-NAME (NOS inhibitor), MB (guanylate cyclase inhibitor) and HB (nitric oxide scavenger) significantly antagonized the hyperalgesic effect of NTG in the phase 2 of the formalin test. These results show that nitric oxide plays an important role in producing hyperalgesia in the spinal cord acting postsynaptically as well as pre-synaptically. 相似文献
99.
Mike Burmester Yvo G. Desmedt Toshiya Itoh Kouichi Sakurai Hiroki Shizuya 《Journal of Cryptology》1999,12(3):197-223
Divertible proofs are extensions of interactive proofs in which an active eavesdropper, the warden, makes the prover and
the verifier untraceable. The warden is transparent to both the prover and the verifier. With subliminal-free proofs the warden
controls subliminal messages. In this paper we present divertible and subliminal-free zero-knowledge proofs for various languages.
We consider both graph isomorphism and
Received September 1992 and revised September 1995 and May 1997 相似文献
100.
Takao Makino Koichi Takase Norimichi Tsumura Toshiya Nakaguchi Yoichi Miyake 《Color research and application》2008,33(6):477-484
In this article, a video‐based analysis for facial skin appearance with an automatic face tracking technique is proposed. The change of skin appearance under various illuminations is observed by illuminating the face from various light source positions, and the changes in facial appearance are recorded as a video stream during this measurement. The recorded video stream is then analyzed to obtain the bidirectional reflectance distribution function (BRDF) at each position of the facial skin. Automatic face tracking is necessary to compensate the facial movement in order to obtain an accurate BRDF measurement at each position. Since conventional face tracking techniques cannot be used for a face illuminated from various light source positions, a new face tracking technique that is robust to the various face shadings has been developed. Experimental studies show the effectiveness of both the proposed video‐based analysis technique and the automatic face tracking technique. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 477–484, 2008 相似文献