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51.
K Higo Y Kubo Y Iwatani T Ono M Maeda H Hiai T Masuda K Kuribayashi F Zhang TY Lamin A Adachi A Ishimoto 《Canadian Metallurgical Quarterly》1997,71(1):750-754
Fv-4 is a mouse gene that dominantly confers resistance to infection with Friend murine leukemia virus (F-MuLV) (S. Suzuki, Jpn. J. Exp. Med. 45:473-478, 1975). Despite complete resistance to ecotropic MuLV infection in mice carrying the Fv-4 gene, it is known that cells carrying the resistance gene in tissue culture do not always show resistance as extensive as that in vivo (H. Yoshikura and T. Odaka, JNCI 61:461-463, 1978). To investigate the immunological effect on resistance in vivo, we introduced the Fv-4 gene into BALB/c nude mice (Fv-4-/- nude[nu/nu]) by mating them with Fv-4 congenic BALB/c mice (Fv-4r/r nude+/+) and examined the susceptibility of the F2 progeny to F-MuLV. All BALB/c nude mice without the Fv-4 gene (Fv-4-/- nude[nu/nu]) were permissive to F-MuLV and developed erythroleukemia within 2 weeks after virus inoculation. The BALB/c nude mice with the Fv-4 gene (Fv-4r/r nude[nu/nu]) did not develop leukemia, and no or little virus was detected in the spleen 7 weeks after virus inoculation. The resistance to F-MuLV was dominant in (Fv-4 congenic BALB/c x BALB/c nude) F1 mice with the Fv-4r/- nude(nu/+) genotype as strictly as in (Fv-4 congenic BALB/c x BALB/c) F1 mice with the Fv-4r/- nude+/+ genotype. However, almost all BALB/c nude mice with the Fv-4r/- nude(nu/nu) genotype developed the disease within 7 weeks, and the virus was detected in all of their spleens even in the mice without leukemia. These results show that the resistance caused by the Fv-4 gene is recessive in nude mice and dominant in BALB/c mice. Some immunological effects, perhaps cell-mediated immunity, may play important roles in the resistance to F-MuLV infection in vivo in addition to the dosage effect of the Fv-4 product. 相似文献
52.
J Alexander C Oseroff J Sidney P Wentworth E Keogh G Hermanson FV Chisari RT Kubo HM Grey A Sette 《Canadian Metallurgical Quarterly》1997,159(10):4753-4761
Transgenic mice expressing chimeric human (alpha1 and alpha2 HLA-A11 domains) and murine (alpha3, transmembrane, and cytoplasmic H-2Kb domains) class I molecules were derived. These mice were used as a model system to study the immunogenicity of human CTL epitopes and also to examine the aspects of Ag processing differences of mice vs man. Immunization of these mice with seven known HLA-A11-restricted CTL epitopes emulsified in IFA resulted in vigorous specific CTL responses. A larger panel of 45 A11-binding peptides was used to examine the relationship between immunogenicity in the HLA-A11/Kb transgenic mice and HLA-A11 binding capacity. Twenty-one of 28 (75%) peptides with high binding affinities (50% inhibitory concentration (IC50), 2-50 nM) and 7 of 13 (54%) intermediate binding peptides (IC50, 50-500 nM range) were immunogenic. In parallel, 19 of these peptides were used for in vitro primary immunizations of PBMC derived from HLA-A11 healthy human donors. It was found that 8 of 8 peptides that were able to elicit CTL in primary human in vitro cultures were also immunogenic in HLA-A11/Kb mice. Finally, HLA-A11/Kb transgenic mice were found to generate an A11/Kb restricted CTL response following immunization with influenza virus A/PR/8/34, suggesting that, at least to some extent, A11 epitopes are generated by transgenic mice as a result of natural in vivo processing and presentation. 相似文献
53.
54.
This short communication describes a simple inexpensive instrument employing optical coupling which eliminates electrical shock hazards to hospital patients during signal acquisition. 相似文献
55.
Kuge S. Kato T. Furutani K. Kikuda S. Mitsui K. Hamamoto T. Setogawa J. Hamade K. Komiya Y. Kawasaki S. Kono T. Amano T. Kubo T. Haraguchi M. Nakaoka Y. Akiyama M. Konishi Y. Ozaki H. Yoshihara T. 《Solid-State Circuits, IEEE Journal of》2000,35(11):1680-1689
A 200-MHz double-data-rate synchronous-DRAM (DDR-SDRAM) was developed. The chip contains a delay-locked loop (DLL) which performs over a wide range of operating conditions. Post-mold-tuning allows precise replica programming. A 200-MHz intra-chip data bus is suitable for DDR operation 相似文献
56.
57.
We revisit the Anisotropic Kepler Problem (AKP), which concerns with trajectories of an electron with anisotropic mass term
in a Coulomb field. This is one of the most fundamental fields in Quantum Chaos. Nowadays various quantum systems are challenging
us. Classical theories of these may have chaos. Quantum mechanics have developed from integrable cases and may have to be
reformulated for such cases. AKP then serves as a suitable testing ground for quantum chaos. We first review a pioneering
work by Martin Gutzwiller (J Math Phys (1977) 18:106). We shall show the systematics of the trajectories using ample figures
from an extensive numerical analysis. Then we focus on the rolê of hyperbolic singularities and we comment on the approximations
in an analytic formulation.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
58.
Satoshi Kubo Koh Hashida Shojiro Hishiyama Tatsuhiko Yamada Shuji Hosoya 《木材化学与工艺学杂志》2015,35(1):62-72
In the alkaline decomposition of a β-O-4 type lignin model compound (erythro-guaiacylglycerol-β-guaiacyl ether, compound 1), an isomeric pair of C6C2 enol-ether (2-methoxy-4-[2-(2-methoxyphenoxy)-vinyl]-phenol, compound 2) was detected as the main decomposition product with no trace of C6C3 enol-ether (4-[3-hydroxy-1-(2-methoxyphenoxy)-propenyl]-2-methoxy-phenol, compound 3) or other dimers. In contrast, compound 2 was not detected in the alkaline decomposition products of compound 3. Under alkaline conditions, the γ-hydroxymethyl group of compound 3 was reduced to form 2-methoxy-4-[1-(2-methoxyphenoxy)-propenyl]-phenol (compound 4). In the HSQC analysis of soda lignin, the formation of substructures of C6C2 type enol-ether (related to compound 2) was confirmed. However, no substructures related to compound 4, which could be formed if a substructure of C6C3 type enol-ether was formed under alkaline conditions, were detected. Therefore, it could be concluded that C6C3 type enol-ethers could not be intermediates of alkaline decomposition products of lignin. 相似文献
59.
Hiroaki Inoue Yuji Arai Tsunao Kishida Ryu Terauchi Kuniaki Honjo Shuji Nakagawa Shinji Tsuchida Tomohiro Matsuki Keiichirou Ueshima Hiroyoshi Fujiwara Osam Mazda Toshikazu Kubo 《International journal of molecular sciences》2015,16(1):1043-1050
Hypoxia-inducible factor (HIF)-2α is considered to play a major role in the progression of osteoarthritis. Recently, it was reported that pressure amplitude influences HIF-2α expression in murine endothelial cells. We examined whether hydrostatic pressure is involved in expression of HIF-2α in articular chondrocytes. Chondrocytes were cultured and stimulated by inflammation or hydrostatic pressure of 0, 5, 10, or 50 MPa. After stimulation, heat shock protein (HSP) 70, HIF-2α, nuclear factor kappa B (NF-κB), matrix metalloproteinase (MMP)-13, MMP-3, and vascular endothelial growth factor (VEGF) gene expression were evaluated. The levels of all gene expression were increased by inflammatory stress. When chondrocytes were exposed to a hydrostatic pressure of 5 MPa, HIF-2α, MMP-13, and MMP-3 gene expression increased significantly although those of HSP70 and NF-κB were not significantly different from the control group. In contrast, HIF-2α gene expression did not increase under a hydrostatic pressure of 50 MPa although HSP70 and NF-κB expression increased significantly compared to control. We considered that hydrostatic pressure of 5 MPa could regulate HIF-2α independent of NF-κB, because the level of HIF-2α gene expression increased significantly without upregulation of NF-κB expression at 5 MPa. Hydrostatic pressure may influence cartilage degeneration, inducing MMP-13 and MMP-3 expression through HIF-2α. 相似文献
60.
Takahito Itoh Takahiro Sakakibara Masashi Tamura Masataka Kubo 《Electrochimica acta》2010,55(4):1419-1424
The hyperbranched polymers (HBP-SA-Acs) with both a sulfonic acid group as a functional group and an acryloyl group as a cross-linker at terminals in different ratios of sulfonic acid group/acryloyl group (SO3H/Ac) were successfully synthesized as a new thermally stable proton-conducting electrolyte. The cross-linked hyperbranched polymer electrolyte membranes (CL-HBP-SAs) were prepared by thermal polymerizations of the HBP-SA-Acs using benzoyl peroxide, and their ionic conductivities under dry condition and thermal properties were investigated. The ionic conductivities of the CL-HBP-SAs were found to be in the range of 2.2 × 10−4 to 3.3 × 10−6 S/cm, depending upon the SO3H unit contents, at 150 °C under dry condition, and showed the Vogel-Tamman-Fulcher (VTF) type temperature dependence, indicating that proton transfer is cooperated by local polymer chain motion. All CL-HBP-SAs were thermally stable up to 260 °C, and they had suitable thermal stability as electrolyte membranes for the high-temperature fuel cells under dry condition. Fuel cell measurement using a single membrane electrode assembly cell with a cross-linked electrolyte membrane was successfully performed under non-humidified condition. It was demonstrated that applying the concept of dry polymer system to proton conduction is one possible approach toward high-temperature fuel cells. 相似文献