巻号一覧
78 巻, 4 号
選択された号の論文の3件中1～3を表示しています
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A superb glycosyl donor in glycosylationTeruaki MUKAIYAMA, Hideki JONA2002 年 78 巻 4 号 p. 73-83
発行日: 2002年
公開日: 2006/10/17
ジャーナル フリーCatalytic and stereoselective glycosylations using glycosyl fluorides are described: 1) activation of armed glycosyl fluorides by trityl tetrakis(pentafluorophenyl)borate [TrB(C6F5)4] catalyst in trifluoromethylbenzene (BTF)-pivalonitrile ('BuCN)(5:1) to afford the corresponding disaccharides in high yields with good to high β-stereoselectivity; 2) activation of disarmed glycosyl fluorides by the combined use of silver tetrakis(pentafluorophenyl)borate [AgB(C6F5)4] and stannous chloride (SnCl2) or stannic chloride
(SnCl4); and 3) selective α or β glycosylation using glycosyl fluoride by an appropriate choice of erotic acid catalysts and solvents. Also, the effect of counter anions of erotic acid catalysts on controlling the stereo-selectivities of glycosylation is newly noted. Finally, efficient one-pot sequential syntheses of trisaccharide, F1α antigen, and branched heptasaccharide are demonstrated.抄録全体を表示PDF形式でダウンロード (1606K) -
Yoshihide KOZAI2002 年 78 巻 4 号 p. 84-90
発行日: 2002年
公開日: 2006/10/17
ジャーナル フリーAn analytical expression for the orbit of a dust particle ejected from a comet is derived as the two-body problem by including solar radiation pressure effects. Then deviations of the semi-major axis, the eccentricity and the epoch of the perihelion passage of the particle from those of the comet are expressed as functions of a parameter depending on the ejection velocity, the size of the particle and the true anomaly at the ejection point. Furthermore, numerical values are computed for comet 55P/Tempel-Tuttle which has produced Leonid meteor showers. Finally, perturbations due to Jupiter, Saturn and Uranus are roughly computed and an idea to predict meteor showers is proposed.抄録全体を表示PDF形式でダウンロード (937K) -
Yoshinori IKARASHI, Kazunori KATO, Mitsuzi YOSHIDA, Hiro WAKASUGI2002 年 78 巻 4 号 p. 91-95
発行日: 2002年
公開日: 2006/10/17
ジャーナル フリーU1B3.3 monoclonal antibody (mAb) was established by immunizing a rat with the tMK-2U lymphoma cell line, derived from athymic nude mice. U1B3.3 mAb recognizes some T cell populations, B cells and natural killer (NK) cells. U1B3.3+ T cells express CD3/T cell receptor (TCR) complex at a unique intensity: between that of TCR-intermediate cells (TCRint cells) and TCRbright cells. TCRint cells strongly express the interleukin-2 receptor β chain (IL-2Rβ), but almost all U1B3.3+ T cells express high or low levels of IL-2Rβ. When purified U1B3.3+ NK1.1-T cells were cultured with IL-2, approximately 14% of the cells acquired expression of NK1.1 molecules, which are expressed on NK cells and natural killer T (NKT) cells. Furthermore, U1B3.3+ NK1.1-T cells killed tumor cells after culture with IL-2. These results indicate that U1B3.3 mAb recognizes a precursor of NK1.1+ cytotoxic T cells generated by IL-2.抄録全体を表示PDF形式でダウンロード (713K)
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