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891.
Okada T Tanaka K Shiro M Shionoya M 《Chemical communications (Cambridge, England)》2005,(11):1484-1486
Heterogeneous assembly of three Ag+ and one Ca2+ ion has been accomplished in a dimeric structure of cyclic hexapeptides, cyclo(l-Ala-l-Met)3. 相似文献
892.
893.
Novel molecular drug carrier: encapsulation of oxaliplatin in cucurbit[7]uril and its effects on stability and reactivity of the drug 总被引:1,自引:0,他引:1
Jeon YJ Kim SY Ko YH Sakamoto S Yamaguchi K Kim K 《Organic & biomolecular chemistry》2005,3(11):2122-2125
Oxaliplatin forms a stable 1:1 inclusion complex with cucurbit[7]uril as indicated by NMR, mass spectrometry, isothermal titration calorimetry and X-ray crystallography. The encapsulation of the drug results in a large enhancement in stability, a moderate decrease in reactivity toward guanosine but a much larger decrease in reactivity toward L-methionine, which suggests the encapsulation not only increases the stability of the drug but also may reduce unwanted side effects caused by protein binding of the platinum drug. A preliminary in vitro assay using various tumor cell lines reveals that the encapsulation results in a decrease in the antitumor activity of oxaliplatin. 相似文献
894.
Hashimoto K Kataoka M Tatsuta M Yasoshima K Yamamoto M Yura T Yamamoto N Urbahns K Gupta JB Li Y 《Chemical & pharmaceutical bulletin》2005,53(10):1314-1317
Herein we report the development of novel, potent and non-peptide luteinizing hormone releasing hormone (LHRH) antagonists. The optimization towards derivatives free from mechanism-based CYP3A4 inhibition is described. The identification of a main metabolite guided us towards structural modifications of the benzyl moiety, which resulted in significant improvements of the CYP3A4 profile, while maintaining potent LHRH antagonist activity. 相似文献
895.
Kentaro Nomakuchi 《Annals of the Institute of Statistical Mathematics》2002,54(3):621-625
In the order restricted statistical inference problem, moments of the distance between a true parameter and the least square estimate are non-decreasing when the true parameter moves along a half line from an initial point in the null space. This follows from stochastically larger property of the distance. 相似文献
896.
Lee JW Kim K Choi S Ko YH Sakamoto S Yamaguchi K Kim K 《Chemical communications (Cambridge, England)》2002,(22):2692-2693
For the first time, host-induced intramolecular charge-transfer complex formation in a guest containing both an electron donor and an electron acceptor is demonstrated in the cucurbit[8]uril cavity, leading to unusual back-folding of the guest molecule. 相似文献
897.
898.
In this paper, a hybrid transducer ultrasonic motor is numerically analyzed by using two equivalent electrical circuit models. A transmission-line model for the torsional vibration in the stator, which can model any torsional vibration mode and their combinations, was introduced and compared with a lumped-element model, which modeled the fundamental torsional resonance mode in the stator. The calculation result by using the transmission-line model demonstrated that the second harmonic torsional vibration increased either with the static spring force by which the rotor was pressed to the stator or with the load torque placed on the rotor. The difference in the calculated motor performance between the two models appeared when the second harmonic torsional vibration became large at a sufficient static spring force. 相似文献
899.
D-branes from matrix factorizations 总被引:1,自引:0,他引:1
B-type D-branes can be obtained from matrix factorizations of the Landau–Ginzburg superpotential. We here review this promising approach to learning about the spacetime superpotential of Calabi–Yau compactifications. We discuss the grading of the D-branes, and present applications in two examples: the two-dimensional torus, and the quintic. To cite this article: K. Hori, J. Walcher, C. R. Physique 5 (2004).
Résumé
Les D-branes de type B peuvent être décrites à partir de factorisations matricielles du super-potentiel de Landau–Ginzburg. On revoit ici cette approche prometteuse pour étudier le super-potentiel en espace-temps de compactifications de Calabi–Yau. On discute la graduation des D-branes, et présente deux exemples : le tore en deux dimensions, ainsi que la quintique. Pour citer cet article : K. Hori, J. Walcher, C. R. Physique 5 (2004). 相似文献900.
Shikii K Seki H Yamaguchi K Disadee W Watanabe T Ishikawa T 《Chemical & pharmaceutical bulletin》2004,52(7):864-865
Polymer-supported (PS) reagents can be easily characterized using a cross polarization magic angle spinning method in solid state (13)C-NMR. The technique was applied to the characterization of PS-dimethylimidazolidinone, analogue to potential heterogeneous dehydrating agent. 相似文献