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81.
Kawase M Kurikawa N Higashiyama S Miura N Shiomi T Ozawa C Mizoguchi T Yagi K 《Journal of Bioscience and Bioengineering》1999,88(4):433-437
Cationic polyamidoamine dendrimers are known to be highly branched cascade polymers. Tripeptide growth factor, glycyl-L-histidyl-L-lysine (GHK), was employed as a ligand for activation or attachment of cells from a rat hepatoma cell line, H4-H-E-C3, and immobilized at the terminus of the dendrimer (GHK-dendrimer) to develop a suitable surface for use as a culture substratum in the bioartificial liver support system (BAL). The growth of cells was inhibited by increasing the number of generations of GHK-dendrimers. On the other hand, urea synthesis and lidocaine clearance of the cells adhered on fifth generation GHK-dendrimers were enhanced much more than on first generation GHK-dendrimers. GHK was shown to act as a growth inhibitor and an activator of hepatoma cells. These properties of GHK are advantageous for the utilization of hepatoma cells in BAL. Ligand-modified dendrimers are very promising for the creation of a high-performance substratum for cell culture and high performance bioartificial organs, as well as for high-performance bioartificial liver systems. GHK may have the potential to be a highly useful ligand. 相似文献
82.
83.
Shin-ichi Hirano Takashi Hayashi Masashi Miura 《Journal of the American Ceramic Society》1990,73(4):885-888
Superconducting Ba2 YCu3 O7-δ thin films were prepared through an organometallic route. Single-phase Ba2 YCu3 O7-δ thin films with preferred orientation were successfully prepared on SrTiO3 (100) single-crystal substrates at 800°C by a dip coating method using partially hydrolyzed Ba-Y-Cu organometallic solutions. Preferentially oriented Ba2 YCu3 -O7-δ thin films were also prepared on MgO (100) substrates. By controlling the partial hydrolysis conditions, a coating solution for precursor thin films was kept accurately at the stoichiometric composition. The use of ozone gas during the pyrolysis of the precursor thin films was found to suppress the formation of BaCO3 . Ba2 YCu3 O7-δ thin films with c -axis orientation perpendicular to a SrTiO3 (100) substrate, which were heat-treated at 900°C for 15 min, exhibited a superconductivity transition with an onset of 90 K and an end of 75 K. 相似文献
84.
Masahiko Nakase Tohru Kobayashi Hideaki Shiwaku Shinichi Suzuki Travis S. Grimes Bruce J. Mincher 《溶剂提取与离子交换》2013,31(7):633-646
ABSTRACTTo effectively separate lanthanides (Ln(III)) from actinides (An(III)), symmetrical 2,2′-bipyridyl (Bpy), 1,10-phenanthroline (Phen), and unsymmetrical N-methyl-N-tolyl-1,10-phenanthroline-2-carboxamide (MeTol-PTA) were investigated. According to the crystal structures and EXAFS experiments, the decreasing ionic radius from light to heavy Ln led to decreases in the Ln–N (Bpy) and Ln–N (Phen) distances, while log β simply increased due to the electrostatic interaction and the order of Ln–O (MeTol-PTA) < Ln–N (Bpy, Phen) < Ln–N (MeTol-PTA) was obtained. This indicated that the bulky phenanthroline moiety of MeTol-PTA may not allow N (MeTol-PTA) to come close to Ln. Consequently, the log β of MeTol-PTA exhibited a local maximum (around Nd). 相似文献
85.
86.
Guanghui Cui Masamichi Fujikawa Shusaku Nagano Masami Sano Hiroshi Takase Tsukasa Miyazaki Shinichi Sakurai Katsuhiro Yamamoto 《Polymer》2014
Polystyrene-b-poly(methyl acrylate) (PS-b-PMA) block copolymer with PS volume fraction of 25.2 vol% was synthesized by atom transfer radical polymerization. Non-pretreated silicon wafers were used as the substrates to prepare perpendicular oriented PS cylinders in PMA matrix via solvent annealing which could induce the transformation of spheres to vertically oriented and hexagonally packed cylinders. The spherical microdomains were formed after the evaporation of solvents from the solutions of the block copolymer in selective solvents mixed from methanol, acetone and dichloromethane. The thickness of films could be as thick as 1000 nm, which were much thicker than usual cases and the cylinders came from the directional coalescence of the spheres, thus any pre-treatments of the substrates were not required for perpendicular orientation. The structures were characterized by small angle X-ray scattering (SAXS), transmission electron microscope (TEM), atom force microscopy (AFM) and grazing incidence small angle X-ray scattering (GISAXS). 相似文献
87.
We studied the use of poly(ethylene glycol) (PEG)-modified dendrimers as a nanocapsule with a biocompatible surface. We designed PEG-modified dendrimers having a shell of hydrophobic amino acid residues in the peripheral moiety of the dendrimer to increase their encapsulation ability. Subsequently, l-phenylalanine or γ-benzyl-l-glutamate residues were introduced to all chain ends of the poly(amidoamine) G4 dendrimers. Furthermore, PEG (MW 2000) chains were attached to the amino acid residues. These hydrophobic amino acid residues rendered the PEG-modified dendrimers as more compact. After binding of Rose Bengal (RB) guest molecules to dendrimers, an assay using the Klotz plot showed that the hydrophobic amino acid layer slightly affected the guest site number, but significantly increased intrinsic binding of the dendrimers to guest molecules. The PEG-modified dendrimers with the hydrophobic amino acid layer were better able to retain guest molecules than the dendrimer without the layer: they are therefore useful for drug delivery. 相似文献
88.
The evolution mechanisms of new high-angle boundaries as well as ultrafine grains at large strains were studied by means of multidirectional forging (MDF) of pure copper at low temperature and aluminum alloy at high temperature, where dynamic recovery operates as a main restoration process. The structural changes can be characterized by the evolution of deformation bands such as microshear or kink bands at moderate strains. Multidirectional forging accelerates the evolution of many mutually crossing microshear or kink bands developed in various directions. The misorientations between (sub)grains increased gradually with increasing cumulative strain, finally leading to the development of a new fine-grained structure. The dynamic grain formation can be resulted from in situ or continuous dynamic recrystallization which is discussed in detail. 相似文献
89.
Nakasone A. Miura K. Prendinger H. Hut P. Holland S. Makino J. 《Computer Graphics and Applications, IEEE》2009,29(5):69-81
Developed in the Second Life 3D online multiuser environment, AstroSim (astrophysics simulation) provides synchronous collaborative visualization for astronomers. Users can play, halt, and rewind simulations and annotate stars interactively to track individual stars and gain a better understanding of stellar dynamics and astrophysics phenomena. This article is part of a special issue on collaborative visualization. 相似文献
90.
Katsunori Takeda Tetsuo Hattori Tetsuya Izumi Hiromichi Kawano Shinichi Masuda 《Artificial Life and Robotics》2010,15(4):421-424
Recently, remote monitoring camera systems have been widely used for security. In such systems, one important function is
that the system automatically detects any change in the scenes from the monitoring cameras. In wireless remote monitoring
camera systems, the images of the scenes are generally transmitted as compressed data (e.g., JPEG file), because of the capacity
of the wireless channel. This article shows the automated detection of the change point in time-series data of compressed
JPEG file quantity (Kbytes) from the monitoring camera by applying the sequential probabilistic ratio test (SPRT) and the
Chow test, which is well known as a standard method for detecting structural change in time-series data. 相似文献