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1.
K Shibata S Takegawa N Koizumi N Yamakoshi E Shimazawa 《Chemical & pharmaceutical bulletin》1992,40(4):935-941
2-Azachlormadinone acetate (5a, 17-acetoxy-6-chloro-2-azapregna-4,6-diene- 3,20-dione), 2-oxachlormadinone acetate (6, 17-acetoxy-6-chloro-2-oxapregna-4,6-diene-3,20-dione) and the derivatives were prepared as potential antiandrogenic agents. Biological evaluation showed that 5a and 6 had a potent antiandrogenic activity when tested in the castrated male rat. 相似文献
2.
In this study, we achieved the first total synthesis of natural prunustatin A (1), a novel inhibitor of glucose-regulated protein 78 (GRP78) expression. A key feature included a 15-membered ring macrocyclization, which was successfully accomplished by employing Shiina macrolactonization using 2-methyl-6-nitrobenzoic anhydride (MNBA) and 4-dimethylaminopyridine (DMAP). 相似文献
3.
The coupled vibrations of a cylindrical shell were analysed by a new method that we called ‘the apparent-elasticity method’. Several types of radiators using cylindrical shells were designed on the basis of analytical results and several acoustical characteristics were measured. In consequence, the analytical results were in good agreement with the experimental data, and the practicability of high intensity ultrasonic radiators using cylindrical shells was demonstrated. 相似文献
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Saigusa D Shibuya M Jinno D Yamakoshi H Iwabuchi Y Yokosuka A Mimaki Y Naganuma A Ohizumi Y Tomioka Y Yamakuni T 《Analytical and bioanalytical chemistry》2011,400(10):3635-3641
We recently demonstrated that nobiletin, a citrus flavonoid, exhibits anti-dementia action in animals. However, no determination methods for the content of nobiletin with beneficial action in the brain of nobiletin-administered animals have been developed, nor has its pharmacokinetics been revealed completely. Here, we established the high-performance liquid chromatography/photodiode array detection method for nobiletin determination using Bond Elut C18 SPE cartridges for extraction, where the calibration curve was linear over 0.025-10 ng, with coefficient of variation of less than 6.76%. This method enabled us to determine pharmacokinetic parameters of nobiletin given intraperitoneally or per os in the brain of mice. 相似文献
6.
We have developed a fetal movement monitoring system based on small displacement measurement of internal tissues. When ultrasonic pulses are transmitted to the fetus, the reflected ultrasonic waves which have a Doppler frequency shift due to the fetal movements are detected by using an ultrasonic pulsed Doppler technique. In this paper, we propose a displacement measurement method for internal tissues which is based on the Doppler signal digital detection technique. In the method, the received ultrasonic RF signals are sampled with a sampling frequency of four times higher than the centre frequency of the ultrasonic waves; the Doppler frequency shift signals are derived using digital signal processing. From the detected signals, the internal displacements are estimated using the arc-tangent method. The basic algorithm of the detection method has already been used in the area of blood flow sensing, however, we apply the algorithm to the displacement measurement of internal tissues. The comparison between the proposed method and the conventional method is presented. The fetal movement quantitative monitoring system based on the method which has been constructed is shown. 相似文献
7.
Nobuhiko Mishima Tomio Yamakoshi Petrosky Miwae Yamazaki 《Journal of statistical physics》1976,14(4):359-380
An extension is given for the Fourier expansion method with the contraction technique, which was introduced by Balescu for quantum statistical systems. This is attained by introducing a diagrammatic method with a concept of moving contraction. Then the hierarchy equation for the Contracted Fourier coefficient of the Wigner distribution function is obtained. As an application, a generalized master equation involvingn-body collision effects and quantum statistical effects is also derived. 相似文献
8.
Nematic liquid crystalline elastomer (LCE) actuators possessing both photoluminescent (PL) and stimuli-responsive functions were fabricated and studied. PL-dyes (1-pyrenemethyl acrylate and 4-bromo-2,6-bis-(1?-methyl-benzimidazolyl) pyridine loaded with Eu(III) ion) were synthesised and characterised, and then the dyes were mixed with an acrylate side-on liquid crystalline monomer, a cross-linker and a photo-initiator. Through magnetic field alignment, well-defined LCE micropillar PL actuators were fabricated from the mixed samples by a method combining soft lithography and photo-polymerisation/photo-cross-linking. Microscopic observations indicated that the LCE micropillars showed reversible thermomechanical deformation at the nematic-to-isotropic transition temperature. During the reversible contraction and extension process, the LCE actuator containing 1-pyrenemethyl moieties showed stable photoluminescence, while for the LCE actuator doped with 4-bromo-2,6-bis-(1-methyl-benzimidazolyl)pyridine/Eu(III) complex, the PL emission was quenched at about 100°C, which was before the pillars contraction occurring at a higher temperature. When cooled down to room temperature, the contracted LCE micropillars recovered their original shape and the initial PL emission state. The micron-sized LCE actuators can be used for thermomechanical devices and machines with different PL functions at the same time. 相似文献
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A tripod molecule with an azobenzene arm was designed as a single molecular tip for noncontact atomic force microscopy (NC-AFM). The azobenzene moiety showed photoisomerization that enabled measurements of the same position of the sample by different tip apexes with different interactions. Photoswitching behavior of the molecule synthesized and adsorbed on Au surfaces was examined and reversible switching between the trans- and cis forms was successfully confirmed by NC-AFM measurements. 相似文献
10.
VladimirA. Azov PhilipJ. Skinner Yoko Yamakoshi Paul Seiler Volker Gramlich Franois Diederich 《Helvetica chimica acta》2003,86(11):3648-3670
We report the synthesis and structural characterization of modified Cram‐type, resorcin[4]arene‐based cavitands. Two main loci on the cavitand backbone were selected for structural modification: the upper part (wall domain) and the lower part (legs). Synthesis of unsymmetrically bridged cavitands with different wall components (i.e., 7, 8 , and 14 – 18 ) was performed by stepwise bridging of the four couples of neighboring, H‐bonded OH‐groups of octol 1a (Schemes 1, 2, 4, and 5). Cavitands with modified legs (i.e., 20, 24, 27 , and 28 ), targeted for surface immobilization, were synthesized by short routes starting from suitable aldehyde starting materials incorporating either the fully preformed leg moieties or functional precursors to the final legs (Schemes 7–10). The new cavitand substitution patterns described in this paper should enable the construction of a wide variety of functional architectures in the future. X‐Ray crystallography afforded the characterization of cavitands 2c (Fig. 3) and 24 (Fig. 7) in the vase conformation, with 2c featuring a well‐ordered CH2Cl2 guest molecule in its cavity. A particular highlight is the X‐ray crystal‐structure determination of octanitro derivative 19 (Scheme 6), which, for the first time, shows a cavitand, lacking substituents in the ortho‐position to the two O‐atoms of the four resorcinol moieties, in the kite‐conformation (Fig. 5). 相似文献