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H Shibayama S Tagawa H Hattori R Inoue S Katagiri T Kitani 《Canadian Metallurgical Quarterly》1995,86(2):719-725
We examined chemotaxis of human plasma cells (PCs) in response to extracellular matrix proteins (ECMs) in the human PC cell lines FR4ds and OPM-1ds. The FR4ds cells expressed beta 1+, beta 3-, alpha 2-, alpha 3-, alpha 4+, alpha 5+, alpha 6+, and alpha v+ integrins, whereas the OPM-1ds cells expressed beta 1+, beta 3-, alpha 2-, alpha 3+, alpha 4+, alpha 5-, alpha 6+, and alpha v+. Fibronectin (FN) and laminin (LN) promoted the chemotaxis of the PCs. An inhibitory assay with anti-integrin monoclonal antibodies (MoAbs) showed that anti-alpha 4 MoAb partially inhibited the chemotaxis of FR4ds and completely inhibited the chemotaxis of OPM-1ds. Anti-alpha 5 MoAb alone had no effect on either of these two lines. Nevertheless, anti-alpha 5 MoAb completely inhibited chemotaxis when it was added with anti-alpha 4 in FR4ds, demonstrating a novel complementary role of VLA-5 toward VLA-4 in the chemotaxis induced by FN. LN facilitated chemotaxis both in OPM-1ds expressing alpha 3 and alpha 6 integrins and in FR4ds expressing alpha 6 integrin alone. Anti-alpha 6 MoAb completely inhibited FR4ds chemotaxis, whereas anti-alpha 3 and -alpha 6 MoAb had synergistic inhibitory effects on the chemotaxis of OPM-1ds. These results indicated that the distribution of PCs in human tissue are determined by at least two factors: the concentration of the ECM proteins FN and LN and the expression of integrins. 相似文献
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Mitsuru Funato Hiroaki Kitani Shizuo Fujita Shigeo Fujita 《Journal of Electronic Materials》1996,25(2):217-222
The effects of GaAs buffer layer and lattice-matching on the nature of deep levels involved in Zn(S)Se/GaAs heterostructures
are investigated by means of deeplevel transient spectroscopy (DLTS). The heterojunction diodes (HDs) where nZn(S)Se is grown
on p+-GaAs by metalorganic vapor phase epitaxy are used as a test structure. The DLTS measurement reveals that when ZnSe is directly
grown on a GaAs substrate, there exist five electron traps A-E at activation energies of 0.20, 0.23, 0.25, 0.37, and 0.53
eV, respectively. Either GaAs buffer layer and lattice-matching may reduce the incorporation of traps C, D, and E, implying
that these traps are ascribed to surface treatment of GaAs substrate and to lattice relaxation. Concentration of trap B, which
is the most dominant level, is proportional to the donor concentration. However, in the ZnSSe/GaAs sub. HD, another trap level,
instead of trap B, locates at the almost same position as that of trap B, and it shows anomalous behavior that the DLTS peak
amplitude changes drastically as changing the rate windows. This is explained by the defect generation through the interaction
between sulfide and a GaAs substrate surface. For the trap A, the concentration is a function of donor concentration and lattice
mismatch, and the origin is attributed to a complex of donor induced defects and dislocations. 相似文献
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Qian Yang Hai Jun Cho Zhiping Bian Mitsuki Yoshimura Joonhyuk Lee Hyoungjeen Jeen Jinghuang Lin Jiake Wei Bin Feng Yuichi Ikuhara Hiromichi Ohta 《Advanced functional materials》2023,33(19):2214939
Thermal transistors that electrically control heat flow have attracted growing attention as thermal management devices and phonon logic circuits. Although several thermal transistors are demonstrated, the use of liquid electrolytes may limit the application from the viewpoint of reliability or liquid leakage. Herein, a solid-state thermal transistor that can electrochemically control the heat flow with an on-to-off ratio of the thermal conductivity (κ) of ≈4 without using any liquid is demonstrated. The thermal transistor is a multilayer film composed of an upper electrode, strontium cobaltite (SrCoOx), solid electrolyte, and bottom electrode. An electrochemical redox treatment at 280 °C in air repeatedly modulates the crystal structure and κ of the SrCoOx layer. The fully oxidized perovskite-structured SrCoO3 layer shows a high κ ≈3 .8 W m−1 K−1, whereas the fully reduced defect perovskite-structured SrCoO2 layer shows a low κ ≈ 0.95 W m−1 K−1. The present solid-state electrochemical thermal transistor may become next-generation devices toward future thermal management technology. 相似文献
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Xinyi He Seiya Nomoto Takehito Komatsu Takayoshi Katase Terumasa Tadano Suguru Kitani Hideto Yoshida Takafumi Yamamoto Hiroshi Mizoguchi Keisuke Ide Hidenori Hiramatsu Hitoshi Kawaji Hideo Hosono Toshio Kamiya 《Advanced functional materials》2023,33(28):2213144
The development of environmentally benign thermoelectric materials with high energy conversion efficiency (ZT) continues to be a long-standing challenge. So far, high ZT has been achieved using heavy elements to reduce lattice thermal conductivity (κlat). However, it is not preferred to use such elements because of their environmental load and high material cost. Here a new approach utilizing hydride anion (H−) substitution to oxide ion is proposed for ZT enhancement in thermoelectric oxide SrTiO3 bulk polycrystals. Light element H− substitution largely reduces κlat from 8.2 W/(mK) of SrTiO3 to 3.5 W/(mK) for SrTiO3−xHx with x = 0.216. The mass difference effect on phonon scattering is small in the SrTiO3−xHx, while local structure distortion arising from the distributed Ti−(O,H) bond lengths strongly enhances phonon scattering. The polycrystalline SrTiO3−xHx shows high electronic conductivity comparable to La-doped SrTiO3 single crystal because the H− substitution does not form a grain boundary potential barrier and thus suppresses electron scattering. As a consequence, SrTiO3−xHx bulk exhibits maximum ZT = 0.11 at room temperature and the ZT value increases continuously up to 0.22 at T = 657 K. The H− substitution idea offers a new approach for ZT enhancement in thermoelectric materials without utilizing heavy elements. 相似文献
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M Mizuki S Tagawa T Machii M Shibano E Tatsumi K Tsubaki H Tako A Yokohama S Satou J Nojima T Hirota T Kitani 《Canadian Metallurgical Quarterly》1998,12(4):499-504
BACKGROUND: One of the most controversial areas in patient selection and donor allocation is the high-risk patient. Risk factors for mortality and major infectious morbidity were prospectively analyzed in consecutive United States veterans undergoing liver transplantation under primary tacrolimus-based immunosuppression. METHODS: Twenty-eight pre-liver transplant, operative, and posttransplant risk factors were examined univariately and multivariately in 140 consecutive liver transplants in 130 veterans (98% male; mean age, 47.3 years). RESULTS: Eighty-two percent of the patients had postnecrotic cirrhosis due to viral hepatitis or ethanol (20% ethanol alone), and only 12% had cholestatic liver disease. Ninety-eight percent of the patients were hospitalized at the time of transplantation (66% United Network for Organ Sharing [UNOS] 2, 32% UNOS 1). Major bacterial infection, posttransplant dialysis, additional immunosuppression, readmission to intensive care unit (P=0.0001 for all), major fungal infection, posttransplant abdominal surgery, posttransplant intensive care unit stay length of stay (P<0.005 for all), donor age, pretransplant dialysis, and creatinine (P<0.05 for all) were significantly associated with mortality by univariate analysis. Underlying liver disease, cytomegalovirus infection and disease, portal vein thrombosis, UNOS status, Childs-Pugh score, patient age, pretransplant bilirubin, ischemia time, and operative blood loss were not significant predictors of mortality. Patients with hepatitis C (HCV) and recurrent HCV had a trend towards higher mortality (P=0.18). By multivariate analysis, donor age, any major infection, additional immunosuppression, posttransplant dialysis, and subsequent transplantation were significant independent predictors of mortality (P<0.05). Major infectious morbidity was associated with HCV recurrence (P=0.003), posttransplant dialysis (P=0.0001), pretransplant creatinine, donor age, median blood loss, intensive care unit length of stay, additional immunosuppression, and biopsy-proven rejection (P<0.05 for all). By multivariate analysis, intensive care unit length of stay and additional immunosuppression were significant independent predictors of infectious morbidity (P<0.03). HCV recurrence was of borderline significance (P=0.07). CONCLUSIONS: Biologic and physiologic parameters appear to be more powerful predictors of mortality and morbidity after liver transplantation. Both donor and recipient variables need to be considered for early and late outcome analysis and risk assessment modeling. 相似文献
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Nerve growth factor (NGF) suppressed the decrease in number of viable PC12 cells after serum withdrawal from culture medium. Accordingly, the amount of bcl-2, a suppressive effector of apoptosis, increased in these cells. Bcl-2 antisense oligonucleotide suppressed not only the NGF-induced increase in bcl-2 but also NGF-induced neuronal differentiation. Results of fluorescent DNA staining indicated that NGF inhibited the chromatin condensation of PC12 cells resulting from serum withdrawal and further that the bcl-2 antisense oligonucleotide canceled this effect of NGF. The present results suggest that NGF rescues PC12 cells from apoptosis induced by serum withdrawal via up-regulation of bcl-2. 相似文献