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排序方式: 共有2995条查询结果,搜索用时 15 毫秒
991.
Lan Zhang Yuanhui Song Atsushi Hosoi Yasuyuki Morita Yang Ju 《Microsystem Technologies》2016,22(3):603-608
In this paper, we report a non-invasive and non-destructive probing method for analyzing the MG63 osteoblast-like cells. High frequency microwave atomic force microscope (M-AFM) can be used to measure the surface topography and microwave image of MG63 cells simultaneously in one scanning process. Under the frequency modulation AFM mode, the M-AFM probe tip can scan above the cell surface, maintaining a constant stand-off distance and the created lateral forces were small enough as not to sweep away or deform the fragile biomolecules. By analyzing the results, quantification such as, the number and distribution of organelles and proteins of MG63 cells as well as their dimension and electrical property information can be characterized. The unique potentials of that M-AFM imaging biological substrates with no damaging manner and nanometer scale resolution, while the original structure and function of the biomolecules during the investigation are preserved, make this technique very attractive to biologists. 相似文献
992.
Keiji Komatsu Takaaki Tsuchiya Yasuhiro Hasebe Tetsuo Sekiya Ayumu Toyama Atsushi Nakamura Hiroki Akasaka Hidetoshi Saitoh 《Journal of Thermal Spray Technology》2014,23(5):885-889
Highly dense, spherical yttria (Y2O3) and erbia (Er2O3) particles were synthesized from their corresponding metal-ethylenediaminetetraacetic (EDTA) complexes. The EDTA·Y·H and EDTA·Er·H complexes were prepared in powdered form. These complexes were used as the staring materials for synthesis of the Y2O3 and Er2O3 particles. The particles were synthesized using an H2-O2 flame produced with a commercial flame spray apparatus. Crystalline structure, surface and cross-sectional morphologies, and elemental distribution of the synthesized particles were investigated. It was confirmed that the crystalline phases of the Y2O3 and Er2O3 particles were homogeneous. In addition, the elemental distribution of the particles was uniform. These results indicate that dense, spherical particles of Y2O3 and Er2O3 have been synthesized with EDTA·Y·H and EDTA·Er·H complexes, respectively. 相似文献
993.
This paper presents the vibration suppression of a boring bar using piezoelectric actuators installed in the boring bar, and an inductor-resister (LR) circuit, which acts as a mechanical dynamic absorber. The frequency response function of the compliance was designed so that its real part is constrained to suppress regenerative chatter. The designed boring bar with an optimally tuned LR circuit was set on a lathe to evaluate its dynamic characteristic, and it was found that the chatter vibration was successfully suppressed in the cutting test. 相似文献
994.
Masaru Yao Shin-ichi Yamazaki Hiroshi Senoh Tetsuo Sakai Tetsu Kiyobayashi 《Materials Science and Engineering: B》2012,177(6):483-487
The performance of 9,10-anthraquinone (AQ), and 5,7,12,14-pentacenetetrone (PT) as active materials for rechargeable lithium batteries was investigated. Positive-electrodes in which AQ and PT were incorporated showed initial discharge capacities of greater than 200 mAh/g(AQ or PT). The obtained discharge capacities suggest that a multi-electron redox reaction takes place in each derivative. The discharge capacity of the positive-electrode with AQ rapidly decreased during the charge/discharge cycles; however, the positive-electrode with PT showed a relatively good cycle-life performance; it maintained about 80% of the initial capacity even after 100 cycles. 相似文献
995.
996.
997.
Matsuura Shinya Hashimoto Tadanori Ishihara Atsushi 《Journal of Porous Materials》2021,28(6):1935-1944
Journal of Porous Materials - In order to crack hydrocarbons with a large molecular weight, it is necessary to diffuse those substrates deeply into the inside of a catalyst. Catalysts having the... 相似文献
998.
Yingxia Song Atsushi Kurose Renshi Li Tomoki Takeda Yuko Onomura Takayuki Koga Junpei Mutoh Takumi Ishida Yoshitaka Tanaka Yuji Ishii 《International journal of molecular sciences》2021,22(10)
Selenium-binding protein 1 (Selenbp1) is a 2,3,7,8-tetrechlorodibenzo-p-dioxin inducible protein whose function is yet to be comprehensively elucidated. As the highly homologous isoform, Selenbp2, is expressed at low levels in the kidney, it is worthwhile comparing wild-type C57BL mice and Selenbp1-deficient mice under dioxin-free conditions. Accordingly, we conducted a mouse metabolomics analysis under non-dioxin-treated conditions. DNA microarray analysis was performed based on observed changes in lipid metabolism-related factors. The results showed fluctuations in the expression of numerous genes. Real-time RT-PCR confirmed the decreased expression levels of the cytochrome P450 4a (Cyp4a) subfamily, known to be involved in fatty acid ω- and ω-1 hydroxylation. Furthermore, peroxisome proliferator-activated receptor-α (Pparα) and retinoid-X-receptor-α (Rxrα), which form a heterodimer with Pparα to promote gene expression, were simultaneously reduced. This indicated that reduced Cyp4a expression was mediated via decreased Pparα and Rxrα. In line with this finding, increased levels of leukotrienes and prostaglandins were detected. Conversely, decreased hydrogen peroxide levels and reduced superoxide dismutase (SOD) activity supported the suppression of the renal expression of Sod1 and Sod2 in Selenbp1-deficient mice. Therefore, we infer that ablation of Selenbp1 elicits oxidative stress caused by increased levels of superoxide anions, which alters lipid metabolism via the Pparα pathway. 相似文献
999.
Ryota Uchida Kosuke Iwamoto Suetada Nagayama Atsushi Miyajima Hinako Okamoto Naoko Ikuta Hiroshi Fukumi Keiji Terao Takashi Hirota 《International journal of molecular sciences》2015,16(5):10105-10120
R-α-lipoic acid (RLA) is an endogenous organic acid, and works as a cofactor for mitochondrial enzymes and as a kind of antioxidant. Inclusion complexes of RLA with α-, β- or γ-cyclodextrins (CD) were prepared and orally administered as a suspension to rats. Among them, RLA/γ-CD showed the highest plasma exposure, and its area under the plasma concentration-time curve (AUC) of RLA was 2.2 times higher than that after oral administration of non-inclusion RLA. On the other hand, the AUC after oral administration of non-inclusion RLA and RLA/γ-CD to pylorus-ligated rats did not differ. However, the AUC after intraduodenal administration of RLA/γ-CD was 5.1 times higher than that of non-inclusion RLA, and was almost comparable to the AUC after intraduodenal administration of RLA-Na solution. Furthermore, the AUC after intraduodenal administration of RLA/γ-CD was not affected by biliary ligation or co-administration of an amylase inhibitor. These findings demonstrated that RLA was absorbed from the small intestine effectively when orally administered as a γ-CD inclusion complex, which could be easily dissolved in the lumen of the intestine. In conclusion, γ-CD inclusion complex is an appropriate formulation for supplying RLA as a drug or nutritional supplement with respect to absorption. 相似文献
1000.
A spherical code is a set of many points arranged at more or less uniform intervals on a hypersphere. Here, we present a spherical code comprising 60,000 points in five-dimensional space and the list of the uniformly distributed reduced stress tensors corresponding to the points. This code benefits tectonic studies. By the way of example, it is demonstrated how the code improves the resolution of stress tensor inversion. 相似文献