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排序方式: 共有697条查询结果,搜索用时 15 毫秒
91.
Murata H Futami J Kitazoe M Kosaka M Tada H Seno M Yamada H 《Journal of Bioscience and Bioengineering》2008,105(1):34-38
Polyethylenimine (PEI) cationization is a powerful strategy for protein transduction into cells. In this study, we attempted the artificial regulation of cell proliferation by protein transduction of the N-terminal domain (1-132 amino acids) of the simian virus 40 large T-antigen (SVLT-N), which inactivates retinoblastoma family proteins but not p53. To deliver SVLT-N into cells, we employed an indirect cationization method by forming a complex of biotynylated SVLT-N through disulfide bonds (biotin-SS-SVLT-N) and PEI-cationized avidin (PEI600-avidin). Using this complex, SVLT-N was transduced into the nucleus of confluent and quiescent Balb/c 3T3 cells and was found to be complexed with a cellular target protein, pRb. Furthermore, SVLT-N transduction induced cell proliferation in spite of confluent conditions. Because SVLT-N thus transduced into cells gradually degraded and was not detectable after a 4-d incubation, transiently transformed cells were obtained by this method. These results suggest that oncogene protein transduction technology has great potential for in vitro regulation of cell proliferation. 相似文献
92.
Watanabe S. Futami F. Okabe R. Ludwig R. Schmidt-Langhorst C. Huettl B. Schubert C. Weber H. 《IEEE journal of selected topics in quantum electronics》2008,14(3):674-680
An optical parametric amplified (OPA) fiber switch is described in this paper. This device switches input signals without shifting the wavelength by changing the polarization state of the signal using optical parametric amplification. The OPA fiber switch features ultra-broadband, highly efficient switching with a high contrast ratio. We experimentally test the prototype of the OPA fiber switch, which uses a highly nonlinear fiber. Optical demultiplexing of 160 Gb/s differential phase-shift keying (DPSK) signals is demonstrated in the whole C-band and shows that it provides almost penalty-free optical detection. The application of amplitude noise suppression with the OPA fiber switch by using parametric gain saturation is then proposed and demonstrated for a 160 Gb/s DPSK signal. When it is set to an amplitude-limiting condition, the OPA fiber switch successfully increases the optical signal-to-noise ratio by 4 dB and effectively suppresses the phase deterioration in 160 Gb/s DPSK transmission by increasing the system margin by more than 5 dB. 相似文献
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Hideo Yamauchi Junichi Ikejiri Fumio Sato Hiroyuki Oshita Tsuyoshi Honma Takayuki Komatsu 《Journal of the American Ceramic Society》2019,102(11):6658-6667
In recent years, the expansion of demand for lithium ion batteries has resulted in soaring prices of the constituent resources. From the viewpoint of safety, studies on all-solid-state batteries are actively being carried out. In this study, we succeeded in driving all-solid-state batteries derived from nontoxic oxide glasses at room temperature without requiring scarce resources such as lithium and cobalt. The main structure of the ceramic batteries with a simple structure in which Na2FeP2O7 crystallized glass and β″-alumina solid solution are joined by pressureless cofiring at 550°C. During the crystallization of Na2O-Fe2O3-P2O5 glass, fusion with the β″-alumina solid solution is achieved. Reversible charge and discharge of 80 mAh/g were achieved at room temperature. It is not necessary to apply pressure during cell preparation or the use of the batteries. Furthermore, the strong junction at the cathode and electrolyte interface does not peel off during charge and discharge over a long period of 623 cycles. Ex situ X-ray photoelectron spectroscopy revealed partial Fe4+ induction and a reversible charge and discharge reaction even after overcharging to 9 V. It was demonstrated that Na2FeP2O7 is very stable against overcharging to 9 V. 相似文献
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97.
Bernard W. Ikua Hisataka Tanaka Fumio Obata Satoshi Sakamoto Takeyasu Kishi Tatsuo Ishii 《Precision Engineering》2002,26(1):821
This paper presents the results of a series of experiments performed to examine the validity of a theoretical model for evaluation of cutting forces and machining error in ball end milling of curved surfaces. The experiments are carried out at various cutting conditions, for both contouring and ramping of convex and concave surfaces. A high precision machining center is used in the cutting tests. In contouring, the machining error is measured with an electric micrometer, while in ramping it is measured on a 3-coordinate measuring machine. The results show that in contouring, the cutting force component that influences the machining error decreases with an increase in milling position angle, while in ramping, the two force components that influence the machining error are hardly affected by the milling position angle. Moreover, in contouring, high machining accuracy is achieved in “Up cross-feed, Up cut” and “Down cross-feed, Down cut” modes, while in ramping, high machining accuracy is achieved in “Left cross-feed, Downward cut” and “Right cross-feed, Upward cut” modes. The theoretical and experimental results show reasonably good agreement. 相似文献
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99.
The pervaporation behaviors of methanol–water by poly(γ-methyl L -glutamate) (PMLG) membrane at non-steady- and steady-state permeation were investigated. The values of t1/2 (time required to reach a half value of steady-state permeation flux) for methanol and water changed and did not change with the component in feed, respectively. Both of the average diffusion coefficients for methanol–and water–PMLG from the mixture changed exponentially with the sorption amount of methanol by the synergetic effect on diffusion. The difference in behavior of non-steady and steady state diffusion was explained by whether Do (diffusion coefficient at zero penetrant concentration) was influenced by the concentration distribution of penetrant in PMLG membrane. 相似文献
100.
Ichikuni Nobuyuki Sato Fumio Shimazu Shogo Uematsu Takayoshi 《Topics in Catalysis》2002,18(1-2):101-104
SiO2-supported NbC catalysts were prepared by using temperature-programmed reactions (TPR). XAFS analysis confirmed that Nb2O5 was reduced to NbO2 in the first TPR stage and converted into NbC in the second TPR stage. Nb particles grew only in the second TPR stage. Formation of highly dispersed NbC particles on SiO2 surfaces was achieved. 相似文献