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排序方式: 共有768条查询结果,搜索用时 31 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.
Kenji Tsutsui Takami Tohyama Sadamichi Maekawa 《Journal of Low Temperature Physics》2003,131(3-4):257-261
We examine theoretically the phonon dynamics in the electron-phonon-coupled systems. The model Hamiltonian is a one-dimensional Hubbard model where the hopping of electrons induces the electron-phonon coupling. The numerically exact diagonalization of the Hamiltonian with truncation of the total number of phonons is performed. We calculate the phonon excitation spectra and find that the softening of phonons occurs in insulating case, and a diffusive character appears in the metallic case. We also calculate the charge and spin excitation spectra and find that the dynamics of the phonon coupled with the hopping of electrons is affected by the low energy charge and spin excitations. 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.
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
6.
The three-dimensional dynamics of two interacting quantized vortex filaments is studied. The equations of motion and the method of numerical calculation follow Schwarz. Whether two approaching filaments reconnect or not depends on their arrangement before approach. When a ring moves toward a line from a distance, only within a critical initial distance they can reconnect. The critical distance is minimized when their circulations are parallel at the closest place, while it increases as their circulations begin to deviate from being parallel. Hence the reconnection probability can be less than unity. 相似文献
7.
Tohru Morii Hiroyuki Hamada Muriel Desaeger Akihiko Gotoh Atsushi Yokoyama Ignaas Verpoest Zen-ichiro Maekawa 《Composite Structures》1995,32(1-4):133-139
This study deals with the impact property and damage tolerance of matrix hybrid composite laminates with different laminate constitution. The matrix hybrid composite laminates consisted of the laminae with a conventional epoxy resin and the laminae with a flexible epoxy resin modified from the conventional resin to avoid the interlaminar delamination. The impact energy absorption ratio greatly depended on the matrix resin placed at the impact face. The energy absorption was almost constant if the conventional resin was placed at the impact surface layer, while it increased exponentially with the increasing fraction of the flexible resin if the flexible resin was placed at the impact face. The impact energy was absorbed by the damage development and propagation in the laminate with conventional resin laminae as the impacted face, while it was absorbed by both the recoverable deformation of the flexible resin and the damage propagation in the laminate with flexible resin laminae as the impacted face. 相似文献
8.
Hideo Sawada Sachiko HataNobuhito Kawasaki Jun-ichi IidzukaKentaro Tokugi Jun KyokaneTomomi Maekawa Tokuzo Kawase 《Polymer》2002,43(3):1035-1038
New fluoroalkyl end-capped fullerene cooligomers were prepared by the reactions of fluoroalkanoyl peroxides with fullerene and comonomers such as acryloylmorpholine, N,N-dimethylacrylamide and acrylic acid. These fluorinated fullerene cooligomers were easily soluble in water and common organic solvents, and were able to reduce the surface tensions of both water and benzene, quite effectively. Additionally, these fullerene cooligomers were found to form a stable monomolecular film at the air-water interface, and the modified polystyrene surface treated with these cooligomers was shown to have a strong hydrophilicity with good oil repellency. 相似文献
9.
10.
Natsuhiko Kuratomi Shinichi Takano Mitsuharu Fukasawa Shinya Maekawa Makoto Kadokura Hiroko Shindo Ei Takahashi Sumio Hirose Yoshimitsu Fukasawa Satoshi Kawakami Hiroshi Hayakawa Hitomi Takada Natsuko Nakakuki Ryoh Kato Tatsuya Yamaguchi Yasuhiro Nakayama Hiromichi Kawaida Hiroshi Kono Taisuke Inoue Tetsuo Kondo Daisuke Ichikawa Nobuyuki Enomoto 《International journal of molecular sciences》2021,22(6)
New biomarkers are needed to further stratify the risk of malignancy in intraductal papillary mucinous neoplasm (IPMN). Although microRNAs (miRNAs) are expected to be stable biomarkers, they can vary owing to a lack of definite internal controls. To identify universal biomarkers for invasive IPMN, we performed miRNA sequencing using tumor-normal paired samples. A total of 19 resected tissues and 13 pancreatic juice samples from 32 IPMN patients were analyzed for miRNA expression by next-generation sequencing with a two-step normalization of miRNA sequence data. The miRNAs involved in IPMN associated with invasive carcinoma were identified from this tissue analysis and further verified with the pancreatic juice samples. From the tumor-normal paired tissue analysis of the expression levels of 2792 miRNAs, 20 upregulated and 17 downregulated miRNAs were identified. In IPMN associated with invasive carcinoma (INV), miR-10a-5p and miR-221-3p were upregulated and miR-148a-3p was downregulated when compared with noninvasive IPMN. When these findings were further validated with pancreatic juice samples, miR-10a-5p was found to be elevated in INV (p = 0.002). Therefore, three differentially expressed miRNAs were identified in tissues with INV, and the expression of miR-10a-5p was also elevated in pancreatic juice samples with INV. MiR-10a-5p is a promising additional biomarker for invasive IPMN. 相似文献