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61.
Ia specificities 22 and 23 were found to be determinants on hybrid Ia molecules, formed by the noncovalent binding of a 26,000--28,000 dalton beta polypeptide chain (Ae) coded by the I-A subregion and a 32,000--35,000 dalton alpha chain (E alpha) coded by the I-E subregion. For expression of Ia.23 the Ae chain, coded by the I-A subregion, must be derived from the H-2d haplotype, while Ab, As, or Ak can provide the complementing beta chain for the expression of Ia.22. For expression of Ia.22 and Ia.23, most Ia.7 positive strains can provide the complementing alpha chain (E alpha), with the one exception of B10.PL (Eu), which is Ia.7 positive but will not complement with Ad to express Ia.23. Antisera were also produced against hybrid Ia antigens by immunizing with F1 cells expressing Ia.22 or Ia.23 generated by generated by trans-complementation. These antisera detect the same specificities as conventional anti-Ia.22 and anti-Ia.23 sera produced against cis-complementing Ia antigens. It is postulated that hybrid Ia determinants are involved in recognition and generation of immune response to antigens under dual Ir gene control. It is also suggested that there are 2 types of Ia specificities: 1) allotypic Ia specificities expressed on the alpha or beta chains (for example, Ia.7 on the E alpha chain) and 2) hybrid Ia specificities, which are unique interaction determinants formed by the association of alpha and beta chains (for example, Ia.22 and Ia.23). These interaction gene products may be involved in antigen recognition and presentation. 相似文献
62.
Ueno K Juodkazis S Shibuya T Yokota Y Mizeikis V Sasaki K Misawa H 《Journal of the American Chemical Society》2008,130(22):6928-6929
We demonstrate the possibility to achieve optical triggering of photochemical reactions via two-photon absorption using incoherent light sources. This is accomplished by the use of arrays of gold nanoparticles, specially tailored with high precision to obtain high near-field intensity enhancement. 相似文献
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Andrei V. Nikitin Semen Mikhailenko Tatsuya Yokota Takeshi Watanabe 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(12):964-973
The absorption spectra of the 12CH4 and 13CH4 molecules have been recorded and assigned in the 5560-6200 cm−1 region. The effects of isotopic substitution for 12C by 13C on the methane vibrational energy levels have been calculated from an ab initio potential energy surface and compared with experiment. Comparison of the results obtained for two isotopic species allows us to confirm the vibrational assignment for the strongest bands of 12CH4 in this region. Good agreement of ab initio calculations with observed energy levels has been demonstrated. A list of the assigned 13CH4 lines valuable in atmospheric applications is reported. 相似文献
65.
Tadamichi Hirabayashi Yoshikazu Nishikawa Kenji Yokota 《Journal of polymer science. Part A, Polymer chemistry》1979,17(12):3823-3833
The alternating copolymerization of 1- and 2-vinylnaphthalene (1-VNap and 2-VNap) with methyl methacrylate (MMA) by using diethylaluminum chloride (Et2AlCl) in toluene at 0°C has been studied. No polymerization could occur without Et2AlCl, and alternating copolymers were obtained only when an equimolar amount of Et2AlCl with MMA was supplied. Through 1H-NMR analyses on both dyad and triad of alternating deuterated 1- and 2-α-d-VNap–MMA copolymers, each configuration could be described successfully by a single parameter, coisotacticity σ, whose value was estimated as 0.41 for the former and 0.56 for the latter copolymer, respectively. A rather low coisotacticity of copoly(1-VNap–MMA) was explained in the terms of steric effect (peri effect) of 1-VNap monomer. 相似文献
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67.
H. Ikezoe N. Shikazono Y. Tomita Y. Sugiyama K. Ideno W. Yokota Y. Nagame S. M. Lee M. Ogihara S. C. Jeong H. Fujiwara D. J. Hinde 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(3):289-293
Mass distributions of fission fragments have been measured for the reaction of19F on197Au as a function of scattering angle. The mean fragment mass is dependent on the scattering angle, the asymmetry increasing with increasing projectile energy. 相似文献
68.
Mitsuko Masutani Tadashige Nozaki Hiroki Sasaki Tesshi Yamada Takashi Kohno Kimiko Shimizu Masahiro Gotoh Masahiko Shiraishi Jun Yokota Setsuo Hirohashi Hitoshi Nakagama Takashi Sugimura 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2004,80(2):114
Poly(ADP-ribose) polymerase-1 (Parp-1) is involved in DNA repair and cell-death induction after DNA damage. Parp-1−/− mice show higher susceptibility to the carcinogenic effects of nitrosamine and azoxymethane. To elucidate the role of alterations of the PARP-1 gene in human carcinogenesis, we examined the expression level of PARP-1 gene in various human tumor cell lines. The presence of gross rearrangement of PARP-1 gene in these cell lines was also examined by Southern blot hybridization analysis. The expression levels of PARP-1 gene in several cell lines, including T-cell leukemia cell lines (Molt-4 and CCRF-CEM), colon cancer cell line (WiDr), and gastric cancer cell lines (KATOIII, OKAJIMA, and MKN45) was substantially lower than in other cancer cell lines. Among the 85 analyzed cell lines, structural alteration of PARP-1 gene was detected in a gastric cancer cell line, MKN28. A low level of PARP-1 expression in human cancer could potentially influence cancer cell growth, differentiation and cancer development by affecting genomic instability, as well as the response of tumors to chemo- and radiotherapy. 相似文献
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