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991.
M. Yosoi H. Akimune I. Daito H. Ejiri H. Fujimura M. Fujiwara K. Hara K. Y. Hara T. Ishikawa M. Itoh Y. Itow T. Kawabata K. Kobayashi M. Nakamura T. Noro E. Obayashi H. Sakaguchi Y. Sakemi M. Shiozawa H. Takeda T. Taki A. Tamii H. Toyokawa N. Tsukahara M. Uchida T. Yamada Y. Yasuda H. P. Yoshida R. G. T. Zegers 《Physics of Atomic Nuclei》2004,67(10):1810-1817
Decay particles from the s-hole states in 11B and 15N have been measured in coincidence with the quasifree 12C(p, 2p) and 16O(p, 2p) reactions at E p =392 MeV. Triton decay is found to be dominant for the 11B(s-hole) state and also found to be larger than α decay for the 15N(s-hole) state despite its smaller Q value compared to α decay. Measured decay branching ratios are discussed in comparison with the results of statistical-model, SU(3)-model, and shell-model calculations. The energy spectra around the s-hole states in both 11B and 15N exhibit some bumplike structures, which can be qualitatively explained by recent shell-model calculations for both nuclei. 相似文献
992.
993.
Kazuhiko Tonooka Norihiko Kamata Koji Yamada Koji Matsumoto Fumio Maruyama 《Journal of Non》1992,150(1-3):185-191
The distribution functions of doped Tb3+ and Nd3+ in silicate, germanate, borate and phosphate glasses, in which cross-relaxation among active ions plays an important role, have been estimated by fluorescence measurements. In order to analyze both the steady state and the transient fluorescence characteristics, a non-linear model for the resonant energy transfer has recently been developed. The experimental fluorescence intensity and decay curves, measured as a function of acceptor concentration, suggested a modified distribution function, which included the effect of the segregation of donors and acceptors. The number of segregated Tb3+ ions at the second nearest neighbor position around a Tb3+ ion was estimated to be 0.1–3.4, depending on the host glass. 相似文献
994.
K Torizumi R Yamada A Ueyoshi M Yasui E Shimizu Y Okamoto T Tuda K Ota S Ohori S Kanda 《Radioisotopes》1988,37(5):285-288
The amino sequence recognizable parathyroid hormones (PTH) in lower and non-lower magnesemic groups in randomized samples were measured by using various kinds of the well established PTH kits. The levels of carboxy terminal, mid-region and intact PTH in lower magnesemic group were more decreased than these in non-lower magnesemic group. It is likely that the shortage of magnesium in serum makes a suppression of PTH secretion. 相似文献
995.
Takeo Yamada 《Linear and Multilinear Algebra》1988,22(4):313-323
Given an n×(n+I) sign matrix (Ab). we are concerned with the condition that guarantees the solution to Ax=b be of a fixded sign pattern. It is shown that each factor of det (1) corresponds. in aone to one way to DM-component of the bipartite graph representation of A. This fact is used to supplement the proof of the graph-theoretic characterization of sign-solvability obtained by Bassett et al. [1] and subsequent authors. 相似文献
996.
Ken-ichi Yamada 《Tetrahedron letters》2004,45(35):6595-6597
Cycloalkyl radicals were directly generated from cycloalkanes via C-H bond cleavage by the action of dimethylzinc-air and underwent an addition reaction with N-tosylimines, giving aminoalkylation products in fair to high yields. 相似文献
997.
Yoichi Habata Sachiko Yamada 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(1-2):17-20
The structure of the silver(I) triflate complex with N,N′,N″,N?-tetrakis-(3′,5′-difluorobenzyl)-1,4,8,11-tetraazacyclotetradecane is reported. The Ag+–π interaction between the Ag+ ion incorporated in the cyclam moiety and the aromatic side-arm was observed in solid and solution by X-ray crystallography and UV–VIS titration experiments, respectively. It is also revealed that the Ag+ complex is stable in gas phase from the FAB-MS. The energy of the Ag+–π interaction was estimated as about 30 kJ/mol by Hartree–Fock/3-21G(*) and DFT (B3LYP/3-21G(*)) calculations. The NBO analysis indicated that s donation is the main contribution to the Ag+–aromatic ring interaction. 相似文献
998.
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
999.
Hirata KS Inoue K Ishida T Kajita T Kihara K Nakahata M Nakamura K Ohara S Sato N Suzuki Y Totsuka Y Yaginuma Y Mori M Oyama Y Suzuki A Takahashi K Yamada M Koshiba M Nishijima K Suda T Tajima T Miyano K Miyata H Takei H Fukuda Y Kodera E Nagashima Y Takita M Kaneyuki K Tanimori T Beier EW Feldscher LR Frank ED Frati W Kim SB Mann AK Newcomer FM Van Berg R Zhang W 《Physical review D: Particles and fields》1991,44(8):2241-2260
1000.