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排序方式: 共有607条查询结果,搜索用时 15 毫秒
101.
Yoshitaka Morimoto Hironobu Hoshino Takashi Sakurai Susumu Terakawa Akira Nagano 《Microscopy research and technique》2009,72(4):317-322
Quantitative evaluation of the ability of bone resorption activity in live osteoclast‐like cells (OCLs) has not yet been reported on. In this study, we observed the sequential morphological change of OCLs and measured the resorbing calcium phosphate (CP) area made by OCLs alone and with the addition of elcatonin utilizing incubator facilitated video‐enhanced microscopy. OCLs, which were obtained from a coculture of ddy‐mouse osteoblastic cells and bone marrow cells, were cultured on CP‐coated quartz cover slips. The CP‐free area increased constantly in the OCLs alone, whereas it did not increase after the addition of elcatonin. This study showed that analysis of the resorbed areas under the OCL body using this method enables the sequential quantitative evaluation of the bone resorption activity and the effect of several therapeutic agents on bone resorption in vitro. Microsc. Res. Tech, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
102.
Kensuke Okuda Takashi Hirota Masaaki Hirobe Tetsuo Nagano Masataka Mochizuki Tadahiko Mashino 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(1-2):89-104
Abstract In order to examine the utility of fullerene as a medicinal application, we evaluated the reaction between fullerene derivatives and active oxygen species in vitro. This paper describes the synthesis of various water-soluble C60 derivatives (cationic and anionic) and evaluation of their superoxide (O2 ?) quenching activity. Cationic C60 derivatives showed fairly high efficiency. 相似文献
103.
Kensuke Okuda Takashi Hirota Masaaki Hirobe Tetsuo Nagano Masataka Mochizuki Tadahiko Mashino 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(3):127-142
Abstract In order to examine the utility of fullerene as a medicinal application, we evaluated the reaction between fullerene derivatives and active oxygen species in vitro. This paper describes the synthesis of various water-soluble C60 derivatives (cationic and anionic) and evaluation of their superoxide (O2 ?) quenching activity. Cationic C60 derivatives showed fairly high efficiency. 相似文献
104.
105.
Feng ZHANG Katsunori OKAWA Makoto KIMURA 《Frontiers of Architecture and Civil Engineering in China》2008,2(3):233-241
In this paper, dynamic behavior of a grouppile foundation with inclined piles in loose sand has been investigated with centrifuge
model tests. The test results are also simulated with elastoplastic dynamic finite element method, in which, not only sectional
force of piles, stress of ground, but also deformation of piles are calculated using a three-dimensional elastoplastic dynamic
finite element analysis (Code name: DGPILE-3D). The numerical analyses are conducted with a full system in which a superstructure,
a pile foundation and surrounding ground are considered together so that interaction between pile foundation and soils can
be properly simulated because the nonlinearities of both the pile and the ground are described with suitable constitutive
models. Different types of piles, vertical pile or inclined pile, are considered in order to verify the different characteristics
of a group pile foundation with inclined piles. The validity of the calculation is verified by the model tests. 相似文献
106.
This paper proposed an algorithm on simultaneous position estimation and calibration of omnidirectional camera parameters for a group of multiple mobile robots. It is aimed at developing of exploration and information gathering robotic system in unknown environment. Here, each mobile robot is not possible to know its own position. It can only estimate its own position by using the measurement value including white noise acquired by two omnidirectional cameras mounted on it. Each mobile robot is able to obtain the distance to those robots observed from the images of two omnidirectional cameras while making calibration during moving but not in advance. Simulation of three robots moving straightly shows the effectiveness of the proposed algorithm. 相似文献
107.
Tarui N Nagano Y Sakane T Matsumoto K Kawada M Uchikawa O Ohkawa S Nakahama K 《Journal of Bioscience and Bioengineering》2002,93(1):44-47
The chiral indan derivative (S)-2 (2-[(8S)-1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl]ethyl-amine) was synthesized by enzyme-catalyzed asymmetric hydrolysis of the racemic acetamide 1 (N-[2-(1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl)ethyl]acetamide). The reaction was carried out using Bacillus sp. SUI-12 screened for the ability to hydrolyze 1 to give (S)-2 with high enantioselectivity. In a scaled-up experiment, a low reaction rate was observed. However, by changing the culture medium and the reaction conditions, it became possible to run the reaction to 40% conversion on a 10-g or more scale, obtaining (S)-2 at >;99% enantiomeric excess (ee). The (S)-2 obtained was available for the synthesis of the melatonin receptor agonist TAK-375 (N-[2-[(8S)-1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl]ethyl]propanamide). 相似文献
108.
Nagano N Sakaguchi K Taoka Y Okita Y Honda D Ito M Hayashi M 《Journal of oleo science》2011,60(9):475-481
Heterotrophic marine protists known as thraustochytrids can synthesize polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA). The biosynthetic pathways of PUFAs in thraustochytrids are poorly understood, however. In this study, we attempted to reveal the enzymes involved in DHA synthesis in thraustochytrids. Nine thraustochytrid strains representing 3 genera (Aurantiochytrium, Schizochytrium, and Thraustochytrium) were used for PCR-based detection of the genes encoding Δ5-elongase and Δ4-desaturase and for fatty acid analysis. The degenerate primers were designed to amplify the Δ5-elongase and Δ4-desaturase genes, and the partial sequences of the enzymes were obtained from the genera Thraustochytrium and Schizochytrium. These fragments were identical to those of known Δ5-elongase and Δ4-desaturase. Neither Δ5-elongase nor Δ4-desaturase was detected in the strains belonging to the genus Aurantiochytrium, however, suggesting that this group likely synthesizes DHA not via the elongation/desaturation pathway but via an alternate pathway such as the polyketide synthase pathway. The fatty acid profiles of thraustochytrids were consistent with the presence of genes involved in PUFA biosynthesis in thraustochytrid genera. Thus, our findings suggest that two biosynthetic pathways for PUFAs exist in these organisms. 相似文献
109.
Hiromi Nabeshi Tomoaki Yoshikawa Akihiro Arimori Tokuyuki Yoshida Saeko Tochigi Toshiro Hirai Takanori Akase Kazuya Nagano Yasuhiro Abe Haruhiko Kamada Shin-ichi Tsunoda Norio Itoh Yasuo Yoshioka Yasuo Tsutsumi 《Nanoscale research letters》2011,6(1):1-6
In this study, complexes composed of poly-l-tyrosine (pLT) and single-walled carbon nanotubes (SWCNTs) were produced and the dispersibility of the pLT/SWCNT complexes in water by measuring the ζ potential of the complexes and the turbidity of the solution were investigated. It is found that the absolute value of the ζ potential of the pLT/SWCNT complexes is as high as that of SWCNTs modified with double-stranded DNA (dsDNA) and that the complexes remain stably dispersed in the water at least for two weeks. Thermogravimetry analysis (TGA) and visualization of the surface structures of pLT/SWCNT complexes using an atomic force microscope (AFM) were also carried out. 相似文献
110.