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81.
Nobuo Inagaki Pranab Kumar Sen 《Annals of the Institute of Statistical Mathematics》1985,37(1):251-269
Summary The basic regularity conditions pertaining to the asymptotic theory of progressively truncated likelihood functions and maximum
likelihood estimators are considered, and the uniform strong consistency and weak convergence of progressively truncated maximum
likelihood estimators are studied systematically.
Work done during the first author's visit (as a visiting scholar) to the University of North Carolina at Chapel Hill, supported
by the Ministry of Education of the Japanese Government.
Work supported by the (U.S.) National Heart, Lung and Blood Institute, Contact NIH-NHLBI-F1-2243-L. 相似文献
82.
Fumiaki Watanabe Mitsuko Masutani Nobuo Kamada Hiroshi Suzuki Hitoshi Nakagama Takashi Sugimura Hirobumi Teraoka 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2004,80(6):248
One immediate cellular response to DNA damage is the polyADP-ribosylation reaction by poly(ADP-ribose) polymerase-1 (Parp-1). The importance of Parp-1 has been established in many cellular processes, such as the maintenance of genomic stability, DNA repair and cell-death induction. Here, we established Parp-1−/− mice of C57BL/6J congenic strain and characterized the role of Parp-1 in cell-cycle progression. In this study, we also improved a method to observe G0/G1 to S-phase transition of splenocytes and bone marrow cells prepared from mice. The cells were cultured and stimulated with mitogens (50 μM ionomycin/1 μM phorbol 12, 13-dibutyrate). We found that addition of a commercially available growth supportive reagent, BM Condimed RH1, greatly enhanced the transition of G0/G1 to the S-phase, which was determined by bromodeoxyuridine (BrdU) incorporation to DNA. Using this method, G0/G1 to the S-phase entry was measured using splenocytes derived from Parp-1−/−, Parp-1+/− and wild-type (Parp-1+/+) mice. DNA synthesis in Parp-1+/+ and Parp-1+/− splenocytes started from day 1 after addition of mitogens, whereas that in Parp-1−/− cells started from day 2. The peak of the S-phase was at day 2 in all genotypes and notably DNA synthesis in Parp-1−/− cells was approximately halved compared to Parp-1+/+ cells on day 2, 3 and 4. These results suggested that Parp-1 is involved in positive regulation of S-phase entry in quiescent mouse splenocytes. 相似文献
83.
84.
Hexafluoroacetone reacted with diphenylketene in the presence of potassium fluoride to give a 1:1 cycloadduct of β-lactone structure. On the other hand, hexafluorothioacetone, liberated from 2,2,4,4-tetrakis(trifluoromethyl)-1,3-dithietane by potassium fluoride, reacted with diphenylketene to give a “reverse” cycloadduct, a 3-thietanone derivative. Several reactions ofthe above product, including a reductive desulfuration of the 3-thietanone derivative were carried out. 相似文献
85.
86.
A laser Doppler imaging system with a TV camera has been constructed and velocity distributions of fluid flow in cross sections of a rectangular channel have been measured. Consequently, it has been found that the system has some advantages in comparison with usual laser Doppler velocimeters, for example, the visualization of flow can be easily achieved. 相似文献
87.
Xestospongin A,B,C and D represent a new class of macrocyclic 1-oxaquinolizidines, have been isolated from Australian sponge . The structure of xestospongin C has been determined by X-ray analysis. 相似文献
88.
Yoshinori Fujimoto Miki Kimura Akihiro Takasu Fathy A.M. Khalifa Masuo Morisaki Nobuo Ikekawa 《Tetrahedron letters》1984,25(14):1501-1504
Deuterated stigmasterols (10, 11 and 12) were chemically synthesized and fed to silk-worm larvae. GC-MS analysis of the metabolites, cholesterol (4) and desmosterol (6), indicates the migration of 25-hydrogen to C-24 position during stigmasterol dealkylation. 22,24(28)-Dienes(8a and 8b) were shown to be converted to 22,24-diene (5), desmosterol and cholesterol. 相似文献
89.
90.
Nobuhiro Kodama Kiyoaki Tanaka Taizo Utsunomiya Yoshio Hoshino Fumiyuki Marumo Nobuo Ishizawa Masanori Kato 《Solid State Ionics》1984,14(1):17-24
Integrated intensities of X-ray reflections from a barium chloride fluoride single crystal were measured at 24, 180, 289, 402, 467 and 610°C. The intensities were used for the determination of the anharmonic potential parameters up to the third order. Harmonic potential parameters for each ion were obtained from the temperature dependence of thermal parameters, and anharmonic potential parameters were determined by the least-squares procedures, utilizing the temperature factor formalism based on the cumulant expansion. As a result, it has been found that the Ba2+ and Cl? ions show an anharmonicity, while no significant anharmonic effect was detected for the F? ion. From the potential calculated around the Cl? and F? ions, it was found that both Cl? and F? ions diffuse more easily within the (001) plane than along the c axis. 相似文献