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461.
Based on the Regge pole fit to the high energy data on the e-p structure functions the q2-dependence of the Pomeranchuk and A2 residues is determined in the non-scaling region. A FESR for vW2 together with knowledge of these Regge residues is employed to confirm the existence of the J = 0 fixed pole in the virtual Compton amplitude. 相似文献
462.
[reaction: see text] Reversible metathesis reactions of pyrazolotriazinones and aliphatic aldehydes or ketones proceed in aqueous, phosphate-buffered media at pH 4 and 40-60 degrees C to generate thermodynamically controlled mixtures of heterocycles. 相似文献
463.
Hasegawa T Fujisawa T Numata M Matsumoto T Umeda M Karinaga R Mizu M Koumoto K Kimura T Okumura S Sakurai K Shinkai S 《Organic & biomolecular chemistry》2004,2(21):3091-3098
Schizophyllans carrying beta-lactoside and alpha-mannoside appendages were prepared from native schizophyllan through NaIO4 oxidation followed by reductive amination using aminoethyl-beta-lactoside and alpha-mannoside, respectively. The resulting schizophyllans form stable macromolecular complexes with polynucleotides, such as poly(C) and poly(dA). Specific affinity between these macromolecular complexes and saccharide-binding proteins was demonstrated by surface plasmon resonance and agarose gel staining assays. beta-lactoside-appended schizophyllan enhanced an antisense activity in hepatocytes which express lactoside-binding proteins on their cell surfaces. 相似文献
464.
465.
We examine the process B-->X(s)gamma in minimal supersymmetry (SUSY) with general squark flavor mix-ings. We include all relevant next-to-leading order (NLO) QCD corrections and dominant NLO SUSY effects from the gluino. We find that gluino-squark corrections to down-type quark masses induce large NLO corrections to the dominant Wilson coefficients whose size is often similar to those at LO, es-pecially at large tan(beta. For micro>0, destructive interference and suppression by the renormalization group running lead to a "focusing effect" of reducing the size of gluino corrections to the branching ratio, and also of reducing the LO sensitivity to flavor mixings among squarks. Constraints from B(B-->X(s)gamma) on the SUSY-breaking scale can become significantly weakened relative to the minimal flavor violation case, even, at large tan(beta, for small flavor mixings. The case of micro<0 also becomes allowed. 相似文献
466.
To clarify the mechanism by which basic drugs accumulate in the lung mitochondria, the binding selectivity of drugs to different submitochondrial components of the perfused rat lung was examined. The accumulation of basic drugs was the highest in the mitochondrial outer membrane fraction. The drug accumulation in this fraction increased with lipid solubility and was dose-dependent. It appears then that selective binding sites for basic drugs are present in the mitochondrial outer membrane. 相似文献
467.
468.
469.
Hisayoshi Itoh Akira Uedono Takeshi Ohshima Yasushi Aoki Masahito Yoshikawa Isamu Nashiyama Shoichiro Tanigawa Hajime Okumura Sadafumi Yoshida 《Applied Physics A: Materials Science & Processing》1997,65(3):315-323
2
+ and Al+ at temperatures from room temperature (RT) to 1200 °C at doses of 1013 and 1015/cm2. It is found from Doppler broadening spectra of annihilation gamma-rays obtained by varying the incident positron energy
that hot-implantation gives rise to clustering of vacancies, whereas it suppresses amorphization and diminishes the thickness
of damaged layers. The average size of such clusters increases with increasing implantation dose and temperature. Vacancy
clustering by hot-implantation can be interpreted by the combination of vacancies during implantation. Vacancy type defects
in the low-dose (1013/cm2) implanted samples are found to be removed by annealing at 1400 °C, whereas large vacancy clusters still remain after 1400 °C
annealing in the high-dose (1
015/cm2) implanted samples. It is also derived from the depth profile of positron diffusion length that positron scattering centers
are produced after annealing at 1400 °C in all implanted samples.
Received: 7 March 1997/Accepted: 6 May 1997 相似文献
470.
Mitsutaka Natsume Yasuo Sekine Masashi Ogawa Hiroe Soyagimi Yoshinori Kitagawa 《Tetrahedron letters》1979,20(36):3473-3476
A novel type of a nucleophilic substitution on the piperidine ring was achieved by a stannous chloride-effected reaction of endoperoxides of N-alkoxycarbonyl-1,2-dihydropyridines with various kinds of carbon nucleophiles. 相似文献