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991.
H Akari Y Yamamoto H Hiwada Y Saito N Takayanagi AH Koyama A Adachi 《Canadian Metallurgical Quarterly》1998,44(3-4):211-214
Fasudil is a potent inhibitor for various protein kinases such as myosin light chain kinase and protein kinase C. It has been used as a drug for improvement of intracranial vasospasm and following ischaemic diseases. In this report, we demonstrate that fasudil suppressed the replication of human immunodeficiency virus type 1 (HIV-1) in mitogen-activated peripheral blood mononuclear cells. Our finding shows that fasudil may be useful as a new and distinct chemotherapeutic agent against HIV-1 infection. 相似文献
992.
Thomas W. Sederberg Takafumi Saito Dongxu Qi Krzysztof S. Klimaszewski 《Computer Aided Geometric Design》1994,11(6):687-706
It is a classical result that two corresponding pencils of lines intersect in a conic section, and likewise any conic section can be expressed as the intersection of two pencils of lines. We here extend the idea of pencils to higher degree families lines, and show that any planar rational curve can be expressed as the intersection of two families of lines. This extension leads to a more efficient implicitization algorithm for curves, in which, for example, the implicit equation of a degree four rational curve can generally be expressed as the determinant of a 2 × 2 matrix (Bezout's resultant produces a 4 × 4 matrix and Sylvester's resultant an 8 × 8 matrix). 相似文献
993.
Y Kametani H Goto A Kobori T Sato K Ando K Hozumi T Nishimura T Saito T Yamamoto S Habu 《Canadian Metallurgical Quarterly》1998,10(8):1203-1210
Antigen stimulation via TCR in mature T cells provides rapid induction of tyrosine phosphorylation of intracellular substrates including ZAP-70. To study the potential involvement of tyrosine phosphorylation in CD4+CD8+ [double-positive (DP)] thymocytes in the positive selection process in vivo, we isolated and analyzed them in the presence of phosphatase inhibitor. DP thymocytes were obtained from TCR transgenic mice (TCR-Tg) expressing MHC class I- or class II-restricted TCR in selecting and non-selecting MHC backgrounds respectively. The phosphorylation of ZAP-70 in DP thymocytes of class I-restricted TCR-Tg was significantly higher in the positively selecting background than in the non-selecting one. However, such a phosphorylation difference between selecting and non-selecting TCR-Tg was found to be considerably less in class II-restricted TCR-Tg. A similar bias for ZAP-70 phosphorylation was also observed on selecting DP thymocytes when I-A(beta) deficient- and beta2-microglobulin-deficient mice were compared. These ex vivo studies suggest that TCR-mediated signaling on DP thymocytes induces ZAP-70 phosphorylation under a different manner of engagement of TCR to class I and class II molecules in the positive selection process. 相似文献
994.
995.
996.
997.
Hajime Arai Masayuki TsudaKeiichi Saito Masahiko HayashiYoji Sakurai 《Electrochimica acta》2002,47(17):2697-2705
Five kinds of nickel dioxide polymorphs, LixNiO2 with x≈0, were prepared by treating LiNiO2 with sulfuric acid solutions, occasionally followed by low-temperature heating. Here we report their structure and properties as lithium insertion electrodes. Acid-treated Li0.10NiO2 with two layered phases turned into a single-layered compound at 160 °C and then to a spinel-related compound at 170 °C. Acid-treated Li0.04NiO2 contained a phase with a cadmium iodide structure, which was not observed with Li0.10NiO2. Heating this Li0.04NiO2 yielded a spinel-related compound on heating. The NiO distances in these compounds suggested that the nickel oxidation state was kept approximately +4. These ‘nickel dioxide’ polymorphs exhibited varied characteristics as lithium insertion electrodes. We discuss the electrode behavior together with the structural changes that occur during lithium insertion. We also examined the effect of the electrode drying condition on the cycling performance. 相似文献
998.
999.
In this paper, we report development of a new process for lead-free solder bumping with no flux residues, using stencil printing and hydrogen radicals, which can lessen both the environmental load and the manufacturing cost of solder bumping. In this process the reduction of the hydrogen radicals, instead of the flux, will eliminate the surface oxides of the stencil printed lead-free solder paste. Sn-3.0Ag-0.5Cu lead-free solder paste, which contains no residue flux was printed on an 8-in wafer. Hydrogen plasma was radiated for a minute during the reflow process, and the printed paste formed a bump. Reflow experiments without hydrogen radicals treatment were also carried out for comparison, where no successful reflow could be observed. 相似文献
1000.
T Osada R Yagi A Kawasumi S Kagoshima N Miura M Oshima G Saito 《Canadian Metallurgical Quarterly》1990,41(8):5428-5431