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61.
Suzuki S Tanaka R Takada K Inoue N Yashima Y Honda A Honda S 《Journal of chromatography. A》2001,910(2):319-329
A method for the analysis of the sialo-N-glycans in glycoproteins was established by the electrokinetic chromatography mode of capillary electrophoresis (CE) in sodium dodecyl sulfate (SDS) micelles as 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatives, using sialo-N-glycans in fetuin as a model. Six major and some minor peaks were observed for the N-glycans in fetuin, which were well separated from each other using 50 mM phosphate buffer, pH 6.0, containing SDS to a concentration of 30 mM in an uncoated fused-silica capillary, and these peaks were assigned to sialo-N-glycans having either of the biantennary or β1-3/β1-4 linked galactose-containing complex type triantennary N-glycans as the basic structures, by an indirect method based on the assignment of the peaks in high-performance liquid chromatography separated in parallel with CE and peak collation between these two separation methods. The attaching position of the sialic acid residue was determined using the linkage preference of neuraminidase isozymes. The established system is considered to be useful for routine analysis of microheterogeneity of the carbohydrate moiety of this model glycoprotein from the following reasons: (1) the derivatization with PMP proceeds quantitatively under mild conditions without causing release of the sialic acid residue, (2) the derivatives can be sensitively detected by UV absorption, (3) the procedure is simple, rapid and reproducible. Preliminary results of N-glycan analysis for several other glycoproteins under these conditions are also presented. 相似文献
62.
Chikako Mese 《Transactions of the American Mathematical Society》2000,352(9):3957-3969
This paper involves the generalization of minimal surface theory to spaces with singularities. Let be an NPC space, i.e. a metric space of non-positive curvature. We define a (parametric) minimal surface in as a conformal energy minimizing map. Using this definition, many properties of classical minimal surfaces can also be observed for minimal surfaces in this general setting. In particular, we will prove the boundary monotonicity property and the isoperimetric inequality for minimal surfaces in .
63.
T. Honda T. Oi T. Ossaka T. Nozaki H. Kakihana 《Journal of Radioanalytical and Nuclear Chemistry》1989,130(1):81-97
Hot spring water and crater lake water samples were analyzed for their rare earth elements: (REE's) by neutron activation method, which, in the irradiation, sample preparation, incorporated a coprecipitation process in which aluminium was used as a collector. Ten REE's, La, Ce, Sm, Eu, Gd, Tb, Dy, Tm, Yb and Lu, were consequently detected and determined at the ppb level with satisfactory precision. It was shown that the aluminium coprecipitation is effective in enhancing concentrations of the REE's and reducing the amounts of interfering nuclides before neutron irradiation. 相似文献
64.
Mutsumi Tashiro Pradeep K. Pujari Shu Seki Yoshihide Honda Shigehiro Nishijima Seiichi Tagawa 《Radiation Physics and Chemistry》2000,58(5-6):587-592
Temperature dependence of positron annihilation lifetime spectra of polysilanes such as, poly(methyl-n-propylsilane) (PMPrS) and poly(di-n-hexylsilane) (PDHS) has been investigated. The τ3 in PMPrS is seen to increase monotonically around the solid–liquid transition temperature. The transition temperature and free volume are observed to depend on the molecular weight and/or packing of the backbones. For PDHS, a sharp change in τ3 and I3 is seen at the solid–solid transition temperature. Free volume radius probability density functions, above and below the transition temperature, are presented in PMPrS and PDHS. Positron studies are complimented by conventional thermal analysis studies. 相似文献
65.
M. Yamaga T. Inoue S. Yabashi M. Honda J.-P. R. Wells K. Shimamura 《辐射效应与固体损伤》2013,168(6-12):977-982
Electron paramagnetic resonance (EPR) spectra of Ce 3+ in LiLuF 4 (LLF) and LiSr 0.8 Ca 0.2 AlF 6 (LSCAF) observed at low temperatures (<20 v K) show that the Ce 3+ centers have tetragonal and pseudo-trigonal symmetry with ( g , g )=(2.751, 1.467) and (2.14, 0.80), respectively. The EPR lines of Ce 3+ in LSCAF are inhomogeneously broadened by different Ce 3+ configurations which correspond to the random occupation of the second nearest neighbor cation sites by Ca 2+ and Sr 2+ and/or charge compensators. These EPR results indicate that the Ce 3+ centers in LLF and LSCAF are associated with substitution of Ce 3+ for Lu 3+ with eight-fold coordination and Sr 2+ /Ca 2+ with six-fold coordination, respectively. Fourier transform infrared absorption has been used to measure transitions between the 2 F 5/2 ground state and the 2 F 7/2 multiplet of Ce 3+ in LLF at 10 v K. The optical absorption and luminescence of Ce 3+ :LLF and Ce 3+ :LSCAF in the UV range are strongly polarized. The energy levels and polarization dependence of the optical transitions can be accounted for in terms of the crystal field potential experienced by the Ce 3+ ions under the action of the different point group symmetries. 相似文献
66.
We prove that any mapping class on a compact oriented surface with non-empty boundary can be made pseudo-Anosov and right-veering
after a sequence of positive stabilizations.
相似文献
67.
68.
69.
Kentaro Okuma Jun-ichi Sakata Yuji Tachibana Takumi Honda Hiroshi Ohta 《Tetrahedron letters》1987,28(52):6649-6652
Wittig reagents were successfully changed to symmetrical olefins when treated with elemental selenium. The reaction proceeds through a selenocarbonyl intermediate, which existence was confirmed by Diels-Alder reaction. 相似文献
70.