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排序方式: 共有491条查询结果,搜索用时 5 毫秒
1.
Mie Kurosawa Yosuke Shikama Masae Furukawa Rieko Arakaki Naozumi Ishimaru Kenji Matsushita 《International journal of molecular sciences》2021,22(5)
Immunosenescence is characterized by age-associated changes in immunological functions. Although age- and autoimmune-related sialadenitis cause dry mouth (xerostomia), the roles of immunosenescence and cellular senescence in the pathogenesis of sialadenitis remain unknown. We demonstrated that acquired immune cells rather than innate immune cells infiltrated the salivary glands (SG) of aged mice. An analysis of isolated epithelial cells from SG revealed that the expression levels of the chemokine CXCL13 were elevated in aged mice. Senescence-associated T cells (SA-Ts), which secrete large amounts of atypical pro-inflammatory cytokines, are involved in the pathogenesis of metabolic disorders and autoimmune diseases. The present results showed that SA-Ts and B cells, which express the CXCL13 receptor CXCR5, accumulated in the SG of aged mice, particularly females. CD4+ T cells derived from aged mice exhibited stronger in vitro migratory activity toward CXCL13 than those from young mice. In a mouse model of Sjögren’s syndrome (SS), SA-Ts also accumulated in SG, presumably via CXCL12-CXCR4 signaling. Collectively, the present results indicate that SA-Ts accumulate in SG, contribute to the pathogenesis of age- and SS-related sialadenitis by up-regulating chemokines in epithelial cells, and have potential as therapeutic targets for the treatment of xerostomia caused by these types of sialadenitis. 相似文献
2.
3.
H Asahara K Fujisawa T Kobata T Hasunuma T Maeda M Asanuma N Ogawa H Inoue T Sumida K Nishioka 《Canadian Metallurgical Quarterly》1997,40(5):912-918
Green fluorescent protein (GFP) is increasingly being used in plant biology from the cellular level to whole plant level. At the cellular level, GFP is being used as an in vivo reporter to assess frequency of transient and stable transformation. GFP has also proven to be an invaluable tool in monitoring trafficking and subcellular localization of protein. At the organ level and up, many exciting applications are rapidly emerging. The development of brighter GFP mutants with more robust folding properties has enabled better macroscopic visualization of GFP in whole leaves and plants. One interesting example has been the use of GFP to monitor virus movement in and among whole plants. GFP is also emerging as a powerful tool to monitor transgene movement and transgenic plants in the field. In a proof-of-concept study, tobacco was transformed with a modified version of the GFP gene controlled by a constitutive (35S) promoter. GFP expression in progeny plants ranged from 0% to 0.5%, and approximately 0.1% GFP was the minimal amount needed for unambiguous macroscopic detection. GFP is the first truly in vivo reporter system useful in whole plants, and we project its usefulness will increase even further as better forms of GFP genes become available. 相似文献
4.
The polarization properties of iodine complex layer deposited by oxidation of poly(vinyl alcohol) (PVA) containing metal iodide were investigated. Heat-resistant polarizing films with high polarization efficiency were produced by oxidizing and stretching the PVA containing metal iodide. The results indicate that i) the polarization efficiency of a polarizing film prepared by oxidation of a PVA film containing 1 mmol or more of potassium iodide (KI)/g PVA at 0°C for 120 s in a 10 wt.-% aqueous solution of H2O2 and a degree of stretching of 400% is high, ii) the heat resistance of the polarizing film in this experiment is higher than that of a filter prepared from a commercial PVA film. 相似文献
5.
T Ayabe H Takenaka O Takenaka A Takenaka H Nagahama H Maruyama A Yamamoto M Nagata Y Koga M Sumida M Hamada 《Canadian Metallurgical Quarterly》1996,38(2):373-381
The pMEX8-hAK1 vector was devised from the pAK plasmid (Kim J. H. et al., 1989, Protein Engineering 5, 379-386), which could directly express human adenylate kinase proteins without recombination and its single strand DNA could be withdrawn with helper phage for random site-directed mutagenesis. The conserved key residues at Lys21, Lys27, and Thr39 were engineered to obtain mutants for kinetic analysis. Three mutants were obtained as K21P, K27R, and T39S, their specific activities were strikingly reduced compared to those of wild type adenylate kinase. This pMEX8-hAK1 will be a powerful tool for site-directed mutagenesis to detect the substrate-enzyme interaction for human adenylate kinase including various other enzymes. 相似文献
6.
Keishi Sakamoto Atsushi Kasugai Masaki Tsuneoka Koji Takahashi Yukiharu Ikeda Tsuyoshi Imai Takashi Nagashima Mitsuru Ohta Tsuyoshi Kariya Kenichi Hayashi Yoshika Mitsunaka Yosuke Hirata Yasuyuki Itoh Yukio Okazaki 《Journal of Infrared, Millimeter and Terahertz Waves》1997,18(9):1637-1654
A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at PRF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at PRF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window. 相似文献
7.
Athermal silica-based arrayed-waveguide grating multiplexer 总被引:4,自引:0,他引:4
Inoue Y. Kaneko A. Hanawa F. Takahashi H. Hattori K. Sumida S. 《Electronics letters》1997,33(23):1945-1947
A temperature dependent channel wavelength shift in a silica-based arrayed-waveguide grating multiplexer is successfully suppressed from 0.95 to 0.05 nm in the 0-85°C temperature range, which means that it can be used in practical WDM systems without the need for temperature control 相似文献
8.
Shinsuke Nagamine Yosuke Mizuno Yuta Hikima Kiyomi Okada Long Wang Masahiro Ohshima 《应用聚合物科学杂志》2021,138(7):49851
Cellulose microfibers (CMFs) having surfaces modified with polydopamine (PDPA) and octadecylamine (ODA) were prepared, and their reinforcing abilities for polypropylene (PP) were investigated. The PDPA coating was made via self-polymerization of dopamine (P-CMF), and subsequent alkylation was conducted by the reaction with ODA (OP-CMF). The modified CMFs exhibited improved dispersibility in the PP matrix due to the reduced hydrophilicity. The OP-CMF/PP composite prepared by batch mixing had a higher tensile modulus compared to that for the pure PP and composites with unmodified CMFs. However, excess alkylation lowered the tensile modulus, and the presence of an optimal degree of alkylation was demonstrated. The CMF/PP-IM composites fabricated by injection molding exhibited improved tensile properties compared to those prepared by batch mixing. Both the tensile modulus and yield stress were increased by increasing the CMF content and improved by the surface modification of the CMFs. 相似文献
9.
Mitsuhiro Shikida Yosuke Niimi Tatsuya Hasegawa Tomoaki Sugino Satoshi Hamaoka Kenji Fukuzawa 《Microsystem Technologies》2015,21(3):661-668
Mechanical strengthening of a Si cantilever by applying KOH wet etching was investigated. Two kinds of Si cantilever specimens having the different crystallographic orientations of the sidewall surfaces, i.e., Si{100} and Si{110}, were fabricated from the same SOI wafer by a Bosch process. The typical height and pitch of the scalloping formed on the sidewall were 248 and 917 nm, respectively. A 50 % KOH (40 °C) chemical wet etching was applied to increase the fracture stress of the Si cantilever. The fracture stress in the both of Si{100} and Si{110} cantilevers increased with the advance of the etching. The obtained maximum fracture stress in Si{100} and Si{110} were 4.2 and 3.7 GPa, respectively. Sidewall surface of the cantilever was analyzed to investigate the mechanical strengthening of Si cantilever by wet etching. The etched surface crystalline was analyzed by the transmission electron microscope (TEM), and confirmed that the thickness of the affected flow layer was less than 10 nm from the obtained TEM image. Then the change of the surface roughness by the KOH etching was analyzed by the atomic force microscope. The surface was smoothened with the advance of the KOH etching. The roughness value of Ra in Si{100} and Si{110} decreased to 12.1 and 37.7 nm, respectively. 相似文献
10.
A wide view auto‐stereoscopic 3D display with an eye‐tracking system for enhanced horizontal viewing position and viewing distance
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Daichi Suzuki Shuji Hayashi Yosuke Hyodo Shinichiro Oka Takeo Koito Hiroki Sugiyama 《Journal of the Society for Information Display》2016,24(11):657-668
This paper describes the development of auto‐stereoscopic three‐dimensional (3D) display with an eye‐tracking system for not only the X‐axis (right–left) and Y‐axis (up–down) plane directions but also the Z‐axis (forward–backward) direction. In the past, the eye‐tracking 3D system for the XY‐axes plane directions that we had developed had a narrow 3D viewing space in the Z‐axis direction because of occurrence of 3D crosstalk variation on screen. The 3D crosstalk variation on screen was occurred when the viewer's eye position moved back and forth along the Z‐axis direction. The reason was that the liquid crystal (LC) barrier pitch was fixed and the LC barrier was able to control the only barrier aperture position. To solve this problem, we developed the LC barrier that is able to control the barrier pitch as well as the barrier aperture position in real time, corresponding to the viewer's eye position. As a result, the 3D viewing space has achieved to expand up to 320–1016 mm from the display surface in the Z‐axis direction and within a range of ±267 mm in the X‐axis direction. In terms of the Y‐axis direction, the viewing space is not necessary to be considered, because of a stripe‐shaped parallax barrier. 相似文献