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71.
Takeda S Terazono B Mishima F Nakagami H Nishijima S Kaneda Y 《Journal of nanoscience and nanotechnology》2006,6(9-10):3269-3276
In the recent progress of gene and cell therapy, novel drug delivery system (DDS) has been required for efficient delivery of small molecules/drugs and also the safety for clinical usage. We have already developed the unique transfection technique by preparing magnetic vector and using permanent magnet. This technique can improve the transfection efficiency. In this study, we directly associated plasmid DNA with magnetic nanoparticles, which can potentially enhance their transfection efficiency by magnetic force. Magnetic nanoparticle, such as magnetite, its average size of 18.7 nm, can be navigated by magnetic force and is basically consisted with oxidized Fe that is commonly used as the supplement drug for anemia. The magnetite particles coated with protamine sulfate, which gives a cationic surface charge onto the magnetite particle, significantly enhanced the transfection efficiency in vitro cell culture system. The magnetite particles coated with protamine sulfate also easily associated with cell surface, leading to high magnetic seeding percentage. From these results, it was found that the size and surface chemistry of magnetic particles would be tailored to meet specific demands on physical and biological characteristics accordingly. Overall, magnetic nanoparticles with different surface modification enhance the association with plasmid DNA and cell surface as well as HVJ-E, which potentially help to improve the drug delivery system. 相似文献
72.
Tohmyoh H Saka M Hirayanma H 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(12):2481-2483
The potential of the water-immersion and dry-contact acoustic imaging techniques for detecting nanometer gaps embedded in silicon is studied. The sensitivity for detecting gaps of over 10 nm in height is governed only by the lateral resolution of the imaging and is independent of the height of the gap. 相似文献
73.
Takuma Uchiyama Hidetsugu Terada Hironori Mitsuya 《Journal of Mechanical Science and Technology》2010,24(1):47-50
Using the 5-degree of freedom parallel-serial hybrid robot, to realize the de-burring, new forward and inverse kinematic calculation
methods based on the “off-line teaching” method are proposed. This hybrid robot consists of a parallel stage section and a
serial stage section. Considering this point, each section is calculated individually. And the continuous path control algorithm
of this hybrid robot is proposed. To verify the usefulness, a prototype robot is tested which is controlled based on the proposed
methods. This verification includes a positioning test and a pose test. The positioning test evaluates the continuous path
of the tool center point. The pose test evaluates the pose on the tool center point. As the result, it is confirmed that this
hybrid robot moves correctly using the proposed methods. 相似文献
74.
Masahiro Shikano Hironori KobayashiShinji Koike Hikari SakaebeYoshiyasu Saito Hironobu HoriHiroyuki Kageyama Kuniaki Tatsumi 《Journal of power sources》2011,196(16):6881-6883
18650-type cylindrical cells using LiNi1/3Mn1/3Co1/3O2 (NMC) and hard carbon as positive and negative electrode material, respectively, were fabricated and degraded by cycle tests. The capacity of the cells remained more than 95% and 85% after cycle tests at 25 and 50 °C, respectively. After the cycle tests, Li-deficient cubic phase was observed on the surface of NMC. This phenomenon should be related to the degradation mechanism of this type of cell. 相似文献
75.
Shaun?D.?Gittard Daisuke?Hojo G.?Kevin?Hyde Giovanna?Scarel Roger?J.?NarayanEmail author Gregory?N.?Parsons 《Journal of Materials Engineering and Performance》2010,19(3):368-373
The antifungal properties of two silver-coated natural cotton fiber structures prepared using a supercritical carbon dioxide
(scCO2) solvent were examined. Scanning electron microscopy confirmed that the scCO2 process may be used to produce cotton fiber textiles with uniform silver nanoparticle coatings. A version of the Kirby-Bauer
disk diffusion test was used to assess the ability of these textiles to inhibit fungal growth. Cotton fabric samples modified
with Ag(hepta) and Ag(cod)(hfac) exhibited measurable zones of inhibition. On the other hand, the uncoated fabric had no zone
of inhibition. Possible applications of antifungal textiles prepared using scCO2 processing include use in hospital uniforms and wound dressings. 相似文献
76.
Ultrathin metallic wires having defects may show much lower strength compared to the strength of the wire material. To characterize ultrathin Pt wires having the nominal diameter of 625 nm, tensile test of the wires was performed by developing a testing platform and a gripping technology. Fracture stress determined by the tensile test showed much higher value compared with that of bulk Pt. However, the fracture stress of some of the wires was lower than the yield stress of the wire determined by the bending test. From the observation of the fracture surfaces, it was found that the lower fracture stress of the wires was due to the defects in the wires and such wires showed brittle fracture behavior. 相似文献
77.
The effects of matrix types on Charpy impact properties were investigated in Fe–0.2%C–1.5%Si–1.5%Mn (mass%) transformation-induced plasticity steels. The steels with annealed martensite and bainitic ferrite matrix possessed higher upper shelf Charpy impact absorbed energy than the steel with polygonal ferrite and martensitic matrix. In addition, the low ductile–brittle fracture appearance transition temperatures were achieved in annealed martensite and martensite types in comparison with those of other steels. 相似文献
78.
An inhibitor of human tyrosinase activity in rum distillate wastewater was isolated and identified as (S)-(+)-imperanene (1). (S)-(+)-Imperanene significantly inhibited tyrosinase isolated from HMV-II cells (IC(50) 1.85 mM). Inhibition kinetics studies revealed that imperanene is a competitive inhibitor of tyrosinase when L-3,4-dihydroxyphenylalanine is used as the substrate. The inhibitory activities of 1, O-beta-D-glucopyranosyl imperanene (2) and O-beta-D-glucopyranosyl-3-methoxyl imperanene (3) were 1>2>3. 相似文献
79.
Koichiro Oishi Genki Saito Kiyoshi Ebina Masanori Nagahashi Kazuo Jimbo Win Shwe Maw Hironori Katagiri Makoto Yamazaki Hideaki Araki Akiko Takeuchi 《Thin solid films》2008,517(4):1449-1452
Cu2ZnSnS4 films were grown on Si (100) by vacuum evaporation using elemental Cu, Sn, S and binary ZnS as sources. X-ray diffraction patterns of films grown at different substrate temperatures indicated that polycrystalline growth was suppressed and the orientational growths were relatively induced in a film grown at higher temperatures. Tetragonal structure of Cu2ZnSnS4 films was confirmed by studying RHEED patterns. The existence of c-axis ([001] direction) growth, two kinds of a-axis (〈100〉 direction) growth and four kinds of {112} twins which can be classified as two symmetrical pairs is proposed. Broad emissions at around 1.45 eV and 1.31 eV were observed in the photoluminescence spectrum measured at 13 K. 相似文献
80.
T Takahashi H Suzuki T Inuzuka H Shibata M Maki 《International journal of molecular sciences》2012,13(6):7532-7549
ALG-2 is a penta-EF-hand Ca(2+)-binding protein and interacts with a variety of intracellular proteins. Two types of ALG-2-binding motifs have been determined: type 1, PXYPXnYP (X, variable; n = 4), in ALIX and PLSCR3; type 2, PXPGF, in Sec31A and PLSCR3. The previously solved X-ray crystal structure of the complex between ALG-2 and an ALIX peptide containing type 1 motif showed that the peptide binds to Pocket 1 and Pocket 2. Co-crystallization of ALG-2 and type 2 motif-containing peptides has not been successful. To gain insights into the molecular basis of type 2 motif recognition, we searched for a new hydrophobic cavity by computational algorithms using MetaPocket 2.0 based on 3D structures of ALG-2. The predicted hydrophobic pocket designated Pocket 3 fits with N-acetyl-ProAlaProGlyPhe-amide, a virtual penta-peptide derived from one of the two types of ALG-2-binding sites in PLSCR3 (type 2 motif), using the molecular docking software AutoDock Vina. We investigated effects of amino acid substitutions of the predicted binding sites on binding abilities by pulldown assays using glutathione-S-transferase -fused ALG-2 of wild-type and mutant proteins and lysates of cells expressing green fluorescent protein -fused PLSCR3 of wild-type and mutants. Substitution of either L52 with Ala or F148 with Ser of ALG-2 caused loss of binding abilities to PLSCR3 lacking type 1 motif but retained those to PLSCR3 lacking type 2 motif, strongly supporting the hypothesis that Pocket 3 is the binding site for type 2 motif. 相似文献