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排序方式: 共有146条查询结果,搜索用时 31 毫秒
1.
A multipath structure of a ring resonator is proposed to expand the free spectral range. Simulation work indicates that the multipath ring resonator has 25 GHz-adjacent-channel crosstalk of -41 dB, maximum interchannel crosstalk of -18 dB, and -1 dB bandwidth of 4 GHz for a typical expansion factor of 10. The results show the advantages of characteristics compared with a double-cavity ring resonator and a triple-coupler ring resonator. 相似文献
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Y Tamura S Takashima JM Cho W Qi K Kamiguchi T Torigoe S Takahashi I Hirai N Sato K Kikuchi 《Canadian Metallurgical Quarterly》1996,87(6):623-630
Certain MHC class I molecules on target cells are known to inhibit the cytotoxic action of NK cells. By using monoclonal antibody (mAb) Cho-1, we have found inhibitory non-MHC class I cell surface molecules that are noncovalently-associated with 200 kDa and 40 kDa antigens. Poly I-C-induced rat NK cells were not cytotoxic to rat fetus-derived fibroblast WFB cell line. In contrast, NK cells were cytotoxic to H-ras oncogene-induced transformants of WFB, W14 and W31. FACS analysis indicated that mAb Cho-1 reacts with WFB, but not with W14 and W31 cells. Thus, this antigen may disappear concomitantly with cell growth and transformation. Cho-1 antigens were also expressed on other NK-resistant lines, such as mouse BALB3T3 fibroblast, EL-4 lymphoma and human fibroblast HEPM. However, they were not expressed on NK-sensitive mouse YAC-1 and H-ras transformant (Brash) of BALB3T3 cells. Furthermore, treatment of target cells with IFN-gamma clearly induced the cell surface expression of Cho-1 antigens, and conferred a resistance to NK cytolysis on target cells. These data strongly suggest that Cho-1 antigen expression may correlate with target cell susceptibility to NK cells. Indeed, treatment of NK-resistant WFB as well as HEPM cells with F(ab')2 fragments of mAb Cho-1 resulted in the acquisition of susceptibility to NK cytolysis. Cho-1 antigens may be novel molecules that regulate the NK resistance of cells. 相似文献
4.
The present study was carried out to examine if the positional distribution of medium-chain fatty acid (MCF) in dietary synthetic
fat influences lymphatic transport of dietary fat and the chemical composition of chylomicrons in rats with permanent cannulation
of thoracic duct. Four types of synthetic triacylglycerol were prepared: (i) sn-1(3) MCF-sn 2 linoleic acid, (ii) interesterified sn-1(3) MCF-sn 2 linoleic acid, (iii) sn-2 MCF-sn-1(3) linoleic acid, and (iv) interesterified sn-2 MCF-sn-1(3) linoleic acid. A purified diet composed of equal amounts of the synthetic fat and cocoa butter was given to rats with
permanent lymph duct cannulation. The positional distribution of MCF in the dietary fat had no significant effect on the lymph
flow, triacylglycerol output, phospholipid output, lipid composition of chylomicrons, or the particle size. The positional
distribution of MCF in the synthetic triacylglycerol was maintained in the chylomicron triacylglycerol. These results showed
that MCF in the dietary triacylglycerol is transported into lymphatics and the positional distribution is well preserved in
chylomicron triacylglycerol. 相似文献
5.
Imoto Taiji; Ueda Tadashi; Tamura Tomohiro; Isakari Yoshimasa; Abe Yoshito; Inoue Makoto; Miki Takeyoshi; Kawano Keiichi; Yamada Hidenori 《Protein engineering, design & selection : PEDS》1994,7(6):743-748
Mutations around His15 which lie far away from the active site,stimulated glycol chitin activity of lysozyme at physiologicaltemperature. Del-Argl4Hisl5 lysozyme, a mutant lysozyme whoseArgl4 and Hisl5 were deleted together, and has the highest activityamong these mutant lysozymes, had a similar binding abilityto a trimer of N-acetyl-glucosamine, a substrate analogue, relativeto native lysozyme. This suggests that the increased activitywas due to an increased kcat in the catalysis reaction. TheH-D exchange rate of the N-1 proton in the Trp63 which is locatedin the active site cleft, was enhanced in the Del-Argl4Hisl5lysozyme, while 2-D proton NMR analysis revealed no conformationalchange around Trp63. We conclude that some sort of fluctuationat the active site might be required for the manifestation ofactivity. This theory is supported by the finding that the Del-Argl4Hisl5lysozyme showed a shift in temperature dependency of activityto lower temperatures compared with that of native lysozyme. 相似文献
6.
Time‐resolved fluorescence properties of 9‐methylanthracene (9MAn) dispersed in film of polyvinylchloride (PVC) containing carbon black were studied under tensile loadings. The fluorescence lifetime of 9MAn decreased from 5.70 to 5.55 ns, whereas the stresses acting on the films increased from 0 to 3 MPa. The change in fluorescence lifetimes of 9MAn during the stress relaxation process showed that the fluorescence lifetimes were correlated with the stresses, not with the strains. The results suggest that 9MAn is a useful probe for monitoring stresses acting on the matrix. With the use of the fluorescence properties of 9MAn, the residual tensile stresses on the skin‐layer of PVC injection‐molded test pieces were estimated. The estimated residual stresses were about ~ 1 MPa. The residual stresses were relaxed to 0 MPa with annealing at 100°C. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2600–2603, 2002 相似文献
7.
Maeda Yoshitake; Koga Hiroshi; Yamada Hidenori; Ueda Tadashi; Imoto Taiji 《Protein engineering, design & selection : PEDS》1995,8(2):201-205
To increase the folding yield of concentrated reduced lysozyme,we developed a renaturation method by means of dialysis fromconcentrated urea with redox agents. After lysozyme was incubatedin the reducing buffer (8 M urea solution) with oxidized glutathione,renaturation of reduced lysozyme was started by dialysis againstthe dialyzing buffer containing 8 M urea with redox agents.The urea concentration of the dialyzing bottle was graduallydiluted with dialyzing buffer without urea at a flow rate of0.1 ml/min by high pressure pump. Using this systematic dialysis,a concentration as high as 5 mg/ml of reduced lysozyme couldbe renaturated in 80% yield, while the folding yield was <5%even at a concentration of 1 mg/ml using a conventional rapiddilution method [Goldberg et al. (1991) Biochemistry, 30, 27902797].Therefore, it was concluded that gentle removal of urea fromdenatured proteins, dissolved in concentrated urea solution,by means of dialysis should be useful to renature denaturedproteins effectively. 相似文献
8.
Akihiro Nagase Eiji Niikura Masaru Shinozaki Tetsuya Nagayasu Taiji Kondo Gosuke Ohashi 《Journal of the Society for Information Display》2013,21(7):295-304
The color gamut is one of the critical parameters that dictate the image quality of displays. The liquid crystal displays using white color light‐emitting diodes (LEDs) as the backlight, though having been widely employed recently, are not very satisfactory in terms of their color gamut because of the broad spectrum inherent to white LEDs. This prompted the authors to develop improved liquid crystal displays using an edge‐lit wide color gamut backlight that used red laser diodes and cyan LEDs. Generating laser beams with high color purity, the laser diodes are light sources with a significant effect on expanding the color gamut. However, laser diodes, red ones in particular, have unfavorable thermal characteristics. To cope with this shortcoming, the authors clearly defined the restrictive criteria for laying out two kinds of light source on the edge‐lit backlight and made a prototype 55‐type laser backlight for performance evaluation. 相似文献
9.
Aiming at the approximate measurement of magnetic rotation angle in optical current sensor based on light intensity detection mode, this paper proposes a current measurement method based on triangular constant transformation to reconstruct magnetic rotation angle, so as to avoid the large current measurement error caused by the approximate measurement of the magnetic rotation angle. By extracting the direct current (DC) component and the alternating current (AC) component of the light intensity signal detected by the photoelectric detector (PD), the sine signal containing the magnetic rotation angle is directly obtained by dividing the two components, and then the triangular identity transformation method is used to linearly demodulate the magnetic rotation angle and reconstruct the current waveform. The experimental results show that the relative error of current measurement does not exceed 1.40% in the current range of 0.05—0.50 A, which is less than the approximate linear measurement (ALM) method, and the magnetic rotation angle and the current have a good linear relationship. 相似文献
10.