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排序方式: 共有2160条查询结果,搜索用时 10 毫秒
991.
Kosuke Imamura Yusuke Tomita Ryo Sato Tokunori Ikeda Shinji Iyama Takayuki Jodai Misako Takahashi Akira Takaki Kimitaka Akaike Shohei Hamada Shinya Sakata Koichi Saruwatari Sho Saeki Koei Ikeda Makoto Suzuki Takuro Sakagami 《International journal of molecular sciences》2022,23(22)
T cells express an actin-binding protein, drebrin, which is recruited to the contact site between the T cells and antigen-presenting cells during the formation of immunological synapses. However, little is known about the clinical implications of drebrin-expressing, tumor-infiltrating lymphocytes (TILs). To address this issue, we evaluated 34 surgical specimens of pathological stage I–IIIA squamous cell lung cancer. The immune context of primary tumors was investigated using fluorescent multiplex immunohistochemistry. The high-speed scanning of whole-slide images was performed, and the tissue localization of TILs in the tumor cell nest and surrounding stroma was automatically profiled and quantified. Drebrin-expressing T cells were characterized using drebrin+ T cells induced in vitro and publicly available single-cell RNA sequence (scRNA-seq) database. Survival analysis using the propensity scores revealed that a high infiltration of drebrin+ TILs within the tumor cell nest was independently associated with short relapse-free survival and overall survival. Drebrin+ T cells induced in vitro co-expressed multiple exhaustion-associated molecules. The scRNA-seq analyses confirmed that the exhausted tumor-infiltrating CD8+ T cells specifically expressed drebrin. Our study suggests that drebrin-expressing T cells present an exhausted phenotype and that tumor-infiltrating drebrin+ T cells affect clinical outcomes in patients with resectable squamous cell lung cancer. 相似文献
992.
Yusuke Motoji Ryuji Fukazawa Ryosuke Matsui Yoshinori Abe Ikuno Uehara Makoto Watanabe Yoshiaki Hashimoto Yasuo Miyagi Noriko Nagi-Miura Nobuyuki Tanaka Yosuke Ishii 《International journal of molecular sciences》2022,23(24)
Kawasaki disease (KD) is an acute inflammatory syndrome of unknown etiology that is complicated by cardiovascular sequelae. Chronic inflammation (vasculitis) due to KD might cause vascular cellular senescence and vascular endothelial cell damage, and is a potential cause of atherosclerosis in young adults. This study examined the effect of KD and HMG-CoA inhibitors (statins) on vascular cellular senescence and vascular endothelial cells. Candida albicans water-soluble fraction (CAWS) was administered intraperitoneally to 5-week-old male apolipoprotein E-deficient (ApoE−) mice to induce KD-like vasculitis. The mice were then divided into three groups: control, CAWS, and CAWS+statin groups. Ten weeks after injection, the mice were sacrificed and whole aortic tissue specimens were collected. Endothelial nitric oxide synthase (eNOS) expression in the ascending aortic intima epithelium was evaluated using immunostaining. In addition, eNOS expression and levels of cellular senescence markers were measured in RNA and proteins extracted from whole aortic tissue. KD-like vasculitis impaired vascular endothelial cells that produce eNOS, which maintains vascular homeostasis, and promoted macrophage infiltration into the tissue. Statins also restored vascular endothelial cell function by promoting eNOS expression. Statins may be used to prevent secondary cardiovascular events during the chronic phase of KD. 相似文献
993.
To establish hydrophilic/hydrophobic effects on polymer‐complexation kinetics, chitosan resins were prepared by radical copolymerization of methacryloyl‐modified chitosans with 2‐hydroxyethyl methacrylate and/or styrene monomers. The primary particles of the gelled copolymers in the suspensions were nicely solidified by basic coagulation bath to form globular beads. Degree of the hydrophilic/hydrophobic properties was controlled by the copolymerization ratio, and each ion‐adsorption kinetics was evaluated by batch method. The initial rate of adsorption in hydrophilic chitosans was higher than that in hydrophobic chitosans, which was attributed to less thickness of the boundary film. We quantitatively evaluated the rate‐determining steps by the initial‐rate analysis, in which the viscosity of the suspension contributes to the film‐diffusion kinetic resistance. The role of hydrophilic/hydrophobic properties of the resins is reasonably rationalized to the length of the boundary films by considering long‐range interactions between the ion and surface. Our results are robust evidence for the ion‐surface interactions. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46493. 相似文献
994.
Mika Yoneda Kuniaki Gotoh Makoto Nakanishi Tatsuo Fujii Yasuhiro Konishi Toshiyuki Nomura 《Journal of the American Ceramic Society》2019,102(6):3468-3476
Cobalt blue is one of the most chemically and thermally stable blue pigments. However, cobalt is scarce and expensive. To minimize the use of cobalt and reduce production costs and toxicity, cobalt blue core-shell pigments were synthesized by a solid-state method, which is cheaper than a liquid-phase reaction. Small cobalt hydroxide particles and large α-alumina particles, in various ratios, were used as the starting materials. The dry mixed powders were calcined at 1200°C for 2 hours. Elemental mappings of the surfaces and cross sections of the synthesized particles showed that the cobalt blue had a core-shell structure. X-ray diffraction patterns showed that the synthesized cobalt blue consisted of an α-alumina core and a cobalt aluminate shell. The color tone of the synthesized cobalt blue was evaluated from the lightness (L*) and chroma (C*) values. The color tone of the cobalt blue synthesized in this study was almost same as those of commercially available samples although the cobalt molar fraction was lower than the stoichiometric ratio (Co/(Co + Al) = 0.33, Co/Al = 0.5) which was calculated from the chemical reaction formula. 相似文献
995.
In this paper, we detect “innovative topics”, those that are new and hopefully interesting to the user. We try to expand user interests significantly by letting the user browse those topics.We first generate user-interest ontologies that allow user profiles to be constructed as a hierarchy of classes where a user interest weight is assigned to each class and instance. Next, we measure the similarity between user interests by using interest weights on their user-interest ontologies and generate user group GU that has high similarity to user u. The innovative topics for u are then detected by determining a suitable size of GU and analyzing the ontologies in GU. 相似文献
996.
An elastic polymer with hydroxymethyl side chains, which contains some crosslinked structure, has been prepared by treating its prepolymer with maleic anhydride and styrene in the presence of an initiator. Its mechanical properties were varied largely by the molar ratio of the hydroxyl group:maleic anhydride:styrene. A typical example of the polymer showed elongation 69%, tensile strength 0.85 kgf/mm2, and Young's modulus 9.4 kgf/mm2. Some other modifications are also examined. 相似文献
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1000.
Makoto Iwata Kohei Katsuraya Ikuo Suzuki Masaki Maeda Naohiko Yasuda Yoshihiro Ishibashi 《Materials Science and Engineering: B》2005,120(1-3):88-90
The voltage drops on the surfaces in PZN–20% PT and PZN–30% PT were investigated using the electrostatic force microscopy (EFM). It was found that the voltage drop per unit length in the a-domain is larger than the one in the c-domains on the sample surface with the ferroelastic domain wall structure, implying that the dielectric constant perpendicular to the spontaneous polarization is larger than the one parallel to the spontaneous polarization in the vicinity of the morphotropic phase boundary (MPB). Dielectric anisotropy in the vicinity of the MPB was discussed. 相似文献