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101.
Within the framework of Bishop's constructive mathematics, we give conditions under which a bounded convex subset of a uniformly smooth normed space over is located, extending results presented recently by F. Richman and H. Ishihara for subsets of a Hilbert space.

  相似文献   

102.
A new polyketide peumusolide A was disclosed as an unprecedented NES non-antagonistic inhibitor for nuclear export of MEK, a promising scaffold for antitumor agents with novel mechanism of action, from Peumus boldus Molina. The absolute stereostructure as well as optical purity was established by use of the two synthesized enantiomeric model lactones. In addition, the Δε values in their CD spectra were demonstrated to be the conclusive index for determination of not only configuration at C-3 but also optical purity of natural congeneric polyketides. Peumusolide A was revealed to show NES non-antagonistic action by the biotinylated probe and to inhibit proliferation of MEK-activated tumor cells selectively.  相似文献   
103.
104.
We study a C -Liouville-integrable and analytic non-integrable Hamiltonian system. We will show that an irregular singular character plays a crucial role in the analytic non-integrability of the system. Partially supported by Grant-in-Aid for Scientific Research (No. 11640183), Ministry of Education, Science and Culture, Japan.  相似文献   
105.
Magnetic response of stratified metal dielectric metamaterial (SMDM) is demonstrated numerically and experimentally. One unit cell of SMDM has a sandwich unit cell consisting of alumina (60 nm)/silver (30 nm)/alumina (60 nm). A Mach–Zehnder interferometer is used to obtain phase information of transmittance and reflectance from which effective permeability is determined. The maximum permeability amounts to 20 and 17 for calculation and experiment, respectively. This huge resonance occurs when the magnetic field is concentrated at the metal layer, while the electric field has a node at the center.  相似文献   
106.
Ryanodine is a potent calcium channel modulator. In this Letter, we report the 10-step synthesis of the highly substituted tricyclic ring system of ryanodine. Diels-Alder reaction via dearomatization of 2,5-dimethylbenzene-1,4-diol and subsequent SmI2-mediated reductive coupling of eight-membered 1,5-diketone efficiently introduced the four consecutive fully substituted carbons of the tricyclo[3.3.2.02,6]decane system.  相似文献   
107.
Experimental observation of current drive by asymmetrical heating of ions in the Texas Tech Tokamak suggests that penetration of the fast Alfven wave near the fundamental ion-cyclotron resonance is restricted. A numerical study of the warm plasma dispersion relation near the ion-cyclotron resonance does indeed show this effect. The data reveal that, as the wave approaches the resonant layer from the high or low field side of the torus, it first passes through a region where asymmetrical heating takes place and the wave energy is absorbed by ions moving with high velocity parallel to the magnetic field  相似文献   
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109.
An acetylcholine sensor was constructed with acetylcholinesterase which was immobilized on a hydrogen ion-selective coated-wire electrode and fundamental properties of this sensor were investigated. Acetylcholine could be determined in the range 0.1–10 rum with response times of 3–10 min. The effects of pH and concentration of buffer solution on the determination and fluctuations in the data obtained with this sensor were also investigated. Possibilities for the practical use of this acetylcholine micro-sensor are suggested.  相似文献   
110.
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