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排序方式: 共有3237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.
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
3.
Tsukada T. Hashimoto Y. Sakata K. Okada H. Ishibashi K. 《Solid-State Circuits, IEEE Journal of》2005,40(1):67-79
A decoupling circuit using an operational amplifier is proposed to suppress substrate crosstalk in mixed-signal system-on-chip (SoC) devices. It overcomes the parasitic inductance problem of on-chip capacitor decoupling. The effect of the proposed decoupling circuit is not limited by parasitic fine impedance. A 0.13-/spl mu/m CMOS test chip showed that substrate noise at frequencies from 40 MHz to 1 GHz was incrementally suppressed by sequentially activating three of the proposed circuits in parallel. The power dissipation of each circuit was 3.3 mW at a 1.0-V power supply. The test chip measurement showed that the proposed decoupling reduced crosstalk by 31% at 200 MHz, whereas it was reduced by 4.4% with capacitor decoupling. This 7:1 ratio, or 17 dB, corresponds to the gain of the opamp. Design of the opamp and its feedback loop for active decoupling is simple, making the opamp useful for SoC applications. 相似文献
4.
The fracture behaviors of gellan hydrogels under compression remarkably depend on the strain rate as well as the boundary conditions for lateral expansion. In the geometry with no constraint for lateral expansion (conventional uniaxial compression), the gels rupture at relatively small strains independently of the compression rates. In contrast, when the gels are compressed extremely slowly (at a strain rate of ca. 10−5 s−1) in the geometry prohibiting the lateral expansion at their top and bottom surfaces, they are remarkably compressible down to 2% of the initial height without macroscopic fracture and they are accompanied by a large amount of water release. In such markedly compressed gels, many microscopic cracks are formed around the central layer, where strain concentration occurs due to the nonuniform deformation arising from the constrained geometry. In the highly compressible case, the formation of macroscopic cracks is prevented by the localization of microscopic cracks as well as the enhancement in mechanical toughness by a significant increase in polymer concentration due to water release. 相似文献
5.
M Ogihara K Aikawa K Ishibashi O Yamaguchi Y Shiraiwa K Koseki 《Canadian Metallurgical Quarterly》1997,43(8):555-560
We investigated the clinical usefulness of individualization of chemotherapeutic regimen in neoadjuvant intra-arterial chemotherapy for locally invasive bladder cancer. Anticancer drugs were selected according to the results of an in vitro chemosensitivity test (collagen matrix assay or succinic dehydrogenase inhibition test). Nine patients with locally invasive bladder cancer received 1 to 4 courses of neoadjuvant intra-arterial chemotherapy, followed by radical cystectomy. Histopathological responses in the cystectomized specimens were grade 3 in 3 cases, grade 2 in 2, grade 1b in 2 and no response in 2. Pathologically, a complete response and downstaging were observed in 3 and 4 cases, respectively. Seven of the 9 patients were alive no evidence of disease with a mean follow-up period of 38.9 months, whereas 2 patients died of metastasis within 2 years. Six of the 7 patients who showed a complete response or down staging have been free of recurrence. These findings suggest that our chemotherapeutic strategy may improve the prognosis for locally invasive bladder cancer. 相似文献
6.
7.
Motofumi Suzuki Kohei Kinoshita Shinji Jomori Hidehiko Harada Kaoru Nakajima Kenji Kimura 《Thin solid films》2007,515(22):8281-8284
The initial stage of iron silicide formation is investigated by high-resolution Rutherford backscattering spectroscopy. During the Fe deposition on Si(001) at 470 °C, the formation of FeSi2 is confirmed by the surface peak analysis. Initially, FeSi2 grows epitaxially so that one of the major crystallographic axes is parallel to the <111> axis of the Si substrate. With increasing Fe deposition, the deviation between the major crystallographic axis of the silicide region and Si<111> increases although the electron diffraction pattern is independent of the amount of Fe deposition. Therefore, the subsurface crystallographic structure of iron silicide is transformed from a cubic-like to a low-symmetry structure. 相似文献
8.
Toru Ikegami Hideyuki Negishi Dai Kitamoto Keiji Sakaki Tomohiro Imura Masayoshi Okamoto Yasushi Idemoto Nobuyuki Koura Tsuneji Sano Kenji Haraya Hiroshi Yanagishita 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(4):381-387
In order to produce highly concentrated bioethanol by pervaporation using an ethanol‐permselective silicalite membrane, techniques to suppress adsorption of succinic acid, which is a chief by‐product of ethanol fermentation and causes the deterioration in pervaporation performance, onto the silicalite crystals was investigated. The amount adsorbed increased as the pH of the aqueous succinic acid solution decreased. The pervaporation performance also decreased with decreasing pH when the ternary mixtures of ethanol/water/succinic acid were separated. Using silicalite membranes individually coated with two types of silicone rubber, pervaporation performance was significantly improved in the pH range of 5 to 7, when compared with that of non‐coated silicalite membranes in ternary mixtures of ethanol/water/succinic acid. Moreover, when using a silicalite membrane double‐coated with the two types of silicone rubber, pervaporation performance was stabilized at lower pH values. In the separation of bioethanol by pervaporation using the double‐coated silicalite membrane, removal of accumulated substances having an ultraviolet absorption maximum at approximately 260 nm from the fermentation broth proved to be vital for efficient pervaporation. Copyright © 2005 Society of Chemical Industry 相似文献
9.
Kenji Kumazaki 《Journal of Infrared, Millimeter and Terahertz Waves》1985,6(8):765-770
Far infrared reflection spectra of CdXHg1?X Se are measured in the region 20 to 600 cm?1 at temperatures between 5 and 77 K. Reflection spectra are explained well by the dynamic dielectric function which is constructed as a sum of Γ8?Γ8 interband, intraband and phonon contributions. The plasmon-LO phonon coupling effect is also discussed. 相似文献
10.
Kenji Nomura Hiromichi OhtaKazushige Ueda Toshio Kamiya Masahiro HiranoHideo Hosono 《Thin solid films》2003,445(2):322-326
We have investigated the characteristics of transparent metal-insulator-semiconductor field-effect transistors (MISFETs) fabricated using InGaO3(ZnO)m (m=integer) single-crystalline thin films as n-channel layers and amorphous alumina as gate insulator films. The MISFETs exhibit good characteristics such as insensitivity to visible light illumination, off-current as low as ∼1 nA with a positive threshold voltage of ∼3 V and on/off current ratio of 105. The field-effect mobility increased from ∼1 to ∼10 cm2 (V s)−1 as the m-value increased. Room temperature Hall mobility also increased. However, unexpectedly these values were lower than the field-effect mobility. It is explained by existence of shallow localized state in the homologous compounds. 相似文献