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排序方式: 共有378条查询结果,搜索用时 15 毫秒
11.
Junya Kondoh Yoichi Tomii Katsuhiro Kawachi 《Journal of the American Ceramic Society》2003,86(12):2093-2102
Methods of suppressing decreased conductivity in 8 mol% Y2 O3 -stabilized–92 mol% ZrO2 (8YSZ) with aging were investigated. Different amounts of Sc2 O3 were doped into 8YSZ. The electrochemical properties of Sc2 O3 -doped 8YSZ were measured, and the microstructural and local structural changes were characterized. The present results indicate that an appropriate amount of Sc2 O3 doping, 3 or 4 mol%, effectively suppresses decreased conductivity with aging in 8YSZ. 相似文献
12.
Masahiko Hayashi Kazuya Yoshimoto Naohito Hirata Kiyoshi Tanaka Nobuki Oguni Katsumasa Harada Akio Matsushita Yasuhiro Kawachi Hiroshi Sasaki 《Israel journal of chemistry》2001,41(4):241-246
Highly enantioselective addition of diketene to aldehydes was achieved by using novel Schiff base—titanium alkoxide complexes. Up to 92% ee of 5-hydroxy-3-oxoesters was obtained. This procedure provides an efficient method for the asymmetric synthesis of potential inhibitors of HMG coenzyme reductase. 相似文献
13.
Haruhiko Ohya Svetlana I. Semenova Aya Sawada Shinichi Fukaya Yohei Suzuki Masahako Aihara Youichi Negishi 《Desalination》2001,140(3):42-245
A relation was obtained between electro-chemical properties of sodium salts (NaCl, NaBr, and Na2SO4), and the thermodynamic property of permeability in symmetrical cellulose acetate membranes, the distribution coefficient K and the kinetic property, the overall diffusion coefficients D. K and D were obtained by the method we proposed using measured unsteady- and steady-state dialysis data. The K values increase with the increase of water content and are in the range of 10−2 for sodium halides and 10−3 for Na2SO4. D is found to increase with the increase of the solute concentration, and the extrapolated values of D to zero concentration D(0) are obtained as 0.015–0.03 μm2/s and increase with the increase of water content in the membrane. D can be divided into the concentration independent diffusion coefficients in the dense part of the membrane Dd and in the porous Dp, applying a two-part (perfect or dense and imperfect or porous) model of the membrane. Contrary to Dd, Dp increases with the increase of Ww and can be correlated as Dp,c =
d exp (γ × Ww). It is shown that the averaged Dd,
D increases with the increase of the quantity of the ionic mobility u of the solutes at infinite dilution divided by valence, and that the parameter γ increases with the increase of the ionic mobility u. The value of K increases slightly with the increase of water content and decreases with the increase of the Flory—Huggins parameter χ. The Flory—Huggins parameter χ is calculated from the measured values of distribution coefficients and data obtained from the literature. And it was found that the gradient of linear decrease of χ (λcation) depends on equivalent ionic conductivity of anion of salt, λan. 相似文献
14.
MicroRNA-331-3p Suppresses Cervical Cancer Cell Proliferation and E6/E7 Expression by Targeting NRP2
Tomomi Fujii Keiji Shimada Aya Asano Yoshihiro Tatsumi Naoko Yamaguchi Masaharu Yamazaki Noboru Konishi 《International journal of molecular sciences》2016,17(8)
Aberrant expression of microRNAs (miRNAs) is involved in the development and progression of various types of cancers. In this study, we investigated the role of miR-331-3p in cell proliferation and the expression of keratinocyte differentiation markers of uterine cervical cancer cells. Moreover, we evaluated whether neuropilin 2 (NRP2) are putative target molecules that regulate the human papillomavirus (HPV) related oncoproteins E6 and E7. Cell proliferation in the human cervical cancer cell lines SKG-II, HCS-2, and HeLa was assessed using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. Cellular apoptosis was measured using the TdT-mediated dUTP nick end labeling (TUNEL) and Annexin V assays. Quantitative RT-PCR was used to measure the messenger RNA (mRNA) expression of the NRP2, E6, E7, p63, and involucrin (IVL) genes. A functional assay for cell growth was performed using cell cycle analyses. Overexpression of miR-331-3p inhibited cell proliferation, and induced G2/M phase arrest and apoptosis in SKG-II, HCS-2 and HeLa cells. The luciferase reporter assay of the NRP2 3′-untranslated region revealed the direct regulation of NRP2 by miR-331-3p. Gene expression analyses using quantitative RT-PCR in SKG-II, HCS-2, and HeLa cells overexpressing miR-331-3p or suppressing NRP2 revealed down-regulation of E6, E7, and p63 mRNA and up-regulation of IVL mRNA. Moreover, miR-331-3p overexpression was suppressed NRP2 expression in protein level. We showed that miR-331-3p and NRP2 were key effectors of cell proliferation by regulating the cell cycle, apoptosis. NRP-2 also regulates the expression of E6/E7 and keratinocyte differentiation markers. Our findings suggest that miR-331-3p has an important role in regulating cervical cancer cell proliferation, and that miR-331-3p may contribute to keratinocyte differentiation through NRP2 suppression. miR-331-3p and NRP2 may contribute to anti-cancer effects. 相似文献
15.
Kinetic Study of the Prooxidant Effect of α-Tocopherol. Hydrogen Abstraction from Lipids by α-Tocopheroxyl Radical 总被引:1,自引:0,他引:1
Aya Ouchi Masaharu Ishikura Kensuke Konishi Shin-ichi Nagaoka Kazuo Mukai 《Lipids》2009,44(10):935-943
A kinetic study of the prooxidant effect of α-tocopherol was performed. The rates of allylic hydrogen abstraction from various
unsaturated fatty acid esters (ethyl stearate 1, ethyl oleate 2, ethyl linoleate 3, ethyl linolenate 4, and ethyl arachidonate 5) by α-tocopheroxyl radical in toluene were determined, using a double-mixing stopped-flow spectrophotometer. The second-order
rate constants (k
p) obtained are <1 × 10−2 M−1 s−1 for 1, 1.90 × 10−2 M−1 s−1 for 2, 8.33 × 10−2 M−1 s−1 for 3, 1.92 × 10−1 M−1 s−1 for 4, and 2.43 × 10−1 M−1 s−1 for 5 at 25.0 °C. Fatty acid esters 3, 4, and 5 contain two, four, and six –CH2– hydrogen atoms activated by two π-electron systems (–C=C–CH2–C=C–). On the other hand, fatty acid ester 2 has four –CH2– hydrogen atoms activated by a single π-electron system (–CH2–C=C–CH2–). Thus, the rate constants, k
abstr/H, given on an available hydrogen basis are k
p/4 = 4.75 × 10−3 M−1 s−1 for 2, k
p/2 = 4.16 × 10−2 M−1 s−1 for 3, k
p/4 = 4.79 × 10−2 M−1 s−1 for 4, and k
p/6 = 4.05 × 10−2 M−1 s−1 for 5. The k
abstr/H values obtained for 3, 4, and 5 are similar to each other, and are by about one order of magnitude higher than that for 2. From these results, it is suggested that the prooxidant effect of α-tocopherol in edible oils, fats, and low-density lipoproteins
may be induced by the above hydrogen abstraction reaction. 相似文献
16.
Kazumitsu Nawata Masako Ii Aya Ishiguro Koichi Kawabuchi 《Mathematics and computers in simulation》2009
We analyze the length of hospital stays of patients hospitalized for cataract and related diseases (Diagnosis Related Groups (DRG) 2041) in Japan, utilizing the data pertaining to 3436 patients on whom one-eye lens operations are performed. We use the discrete-type proportional hazard model to analyze variables that may affect the length of stay. 相似文献
17.
S Tokunaga S Morita Y Tomita Y Toshima M Masuda Y Imoto F Fukumura T Nakano R Tominaga R Kawachi H Yasui 《Canadian Metallurgical Quarterly》1996,49(13):1063-1068
Japanese Society of Cryopreserved Thoracic Tissue Implantation was recently set up. Cryopreserved allograft valves are about to pervade in Japan. To clarify the interest, demands and supply of cryopreserved allograft valve in the area of Kyushu and Yamaguchi, we performed questionnaire investigation regarding this issue. Collection rate of this questionnaire was 87.5% (35/40 hospitals). Ninety-seven percent of the hospitals answered that they were interested in cryopreserved allograft. Ninety-four percent of the hospitals answered that they did not ethically hesitate to use cryopreserved allograft. Ninety-one percent of the hospitals hoped to perform cardiac surgery using allograft aortic valve if allograft is available. With respect to securing donors of allograft, two-third of the hospitals did not decide whether they could be involved in obtaining donors of allograft. As the number of the cadaver kidney donors is about 20 per year in the area of Kyushu and Yamaguchi, shortage of donors of allograft valve is anticipated. 相似文献
18.
The first trial on the fabrication of completely synthesised VAD single-mode fibre is reported. Successful formation of a large deposited cladding-to-core diameter ratio of 10 leads to redundancy of silica jacketing tubes. 相似文献
19.
Low-loss single-mode fibres with GeO2-doped SiO2 cores have been made by the c.v.d. method and the loss spectrum from 0.6 to 1.8 ?m measured. The minimum loss of the fibre with suitably designed parameters, characterised by the refractive-index difference and the core diameter, was 0.75 dB/km at 1.05 ?m. 相似文献
20.
As a first step in developing a new psychophysiological technique to assess mental workload in human-computer interaction (HCI), we recorded event-related brain potentials for visual stimuli triggered by voluntary mouse clicks. Twelve university students clicked a mouse button at their own pace. Each click triggered 1 of 3 alphabetic letters assigned to frequent standard, rare target, and rare nontarget stimuli. Counting target stimuli was required. Both rare stimuli elicited a P3 (P300) wave, the amplitude of which was larger when the stimuli were triggered by mouse clicks than when the same stimuli were presented automatically without mouse clicks. Postmotor potentials associated with clicking were small in amplitude (<2 microV) and did not temporally overlap with the P3. The findings suggest that the P3 can be recorded for a computer's response to the user's intentional action and may be used as a measure of perceptual-central processing resources allocated to the HCI task. Actual or potential applications of this research include the evaluation of the user's attentional state during HCI byrecording brain potentials in the "mouse click" or action-perception paradigm. 相似文献