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951.
Cooper N Hagan DR Tiberghien A Ademefun T Matthews CS Howard PW Thurston DE 《Chemical communications (Cambridge, England)》2002,(16):1764-1765
Three novel C2-aryl substituted pyrrolobenzodiazepines (PBDs) have been synthesised and evaluated in a number of cell lines revealing selective cytotoxicity at the sub-nanomolar level towards melanoma and ovarian cancer cell lines. 相似文献
952.
953.
J.A. Arnaud 《Optics Communications》1973,7(4):313-316
It is shown that the force exerted by plane electromagnetic waves on multilayer media can be evaluated in terms of the changes in momentum flow that take place at the planes of discontinuity. The expression obtained is relevant to radiation pressure experiments. 相似文献
954.
We extend operators from the Cameron-Martin space to Gaussian Lusinian locally convex space. We then are allowed to give sense to the Mehler formula for every such bounded operator. An application is made to Hilbert-Schmidt operators. Next we show that capacities asociated to second quantizations of operators are tight on compact sets, and this is a general result even if the underlying space is not a Banach space.
Le deuxième auteur a exposé ce travail au colloque d'Amersfoort, août 1991. 相似文献
955.
[reaction: see text] A novel class of chiral hemicryptophane hosts has been synthesized in diastereoisomerically pure form, namely, M-(R,R,R)-1a/P-(S,S,S)-1a and M-(S,S,S)-1b/P-(R,R,R)-1b. The C3-symmetrical precursor 9 was prepared, using either (R)- or (S)-glycidyl nosylate, repectively, as the chiral pool reactant and subsequently cyclized (trimerized) in the presence of Sc(OTf)3. The four stereoisomers were fully characterized and displayed two pairs of mirror-image CD spectra, which were used to determine their absolute configuration. The formation of the oxovanadium(V) complex of hemicryptophane 1a is also reported. 相似文献
956.
Jacquemard U Routier S Tatibouët A Kluza J Laine W Bal C Bailly C Mérour JY 《Organic & biomolecular chemistry》2004,2(10):1476-1483
We report the synthesis of a series of novel diphenylcarbazoles designed to interact with DNA. The compounds bearing two or three dimethylaminoalkyloxy side chains were found to bind much more tightly to DNA, preferentially at AT-rich sites, than the corresponding hydroxy compounds. The DNA binding compounds exhibit potent cytotoxic activity toward P388 leukemia cells. The 3,6-diphenylcarbazole thus represent an interesting scaffold to develop antitumor agents interacting with nucleic acids. 相似文献
957.
Arnaud Münch 《Comptes Rendus Mathematique》2004,339(10):733-738
We present a parameterized family of finite difference schemes for the exact controllability of the 1-D wave equation. These schemes differ from the usual centered ones by additional terms of order to , where h denotes the discretization step in space. Using a discrete version of Ingham's inequality for nonharmonic Fourier series, the spectral properties and dispersion diagrams of the schemes, we determine the parameters leading to a uniform controllability property with respect to h and an optimal stability CFL condition. To cite this article: A. Münch, C. R. Acad. Sci. Paris, Ser. I 339 (2004). 相似文献
958.
If is an irrational number, we let {pn/qn}n0, be the approximants given by its continued fraction expansion. The Bruno series B() is defined as
The quadratic polynomial P:ze2iz+z2 has an indifferent fixed point at the origin. If P is linearizable, we let r() be the conformal radius of the Siegel disk and we set r()=0 otherwise. Yoccoz proved that if B()=, then r()=0 and P is not linearizable. In this article, we present a different proof and we show that there exists a constant C such that for all irrational number with B()<, we have
Together with former results of Yoccoz (see [Y]), this proves the conjectured boundedness of B()+logr(). 相似文献
959.
960.
We consider a continuous family (fs), s[0,1] of complex polynomials in two variables with isolated singularities, that are Newton non-degenerate. We suppose that the Euler characteristic of a generic fiber is constant. We firstly prove that the set of critical values at infinity depends continuously on s, and secondly that the degree of the fs is constant (up to an algebraic automorphism of 2).Mathematics Subject Classification (2000): 32S20 (Primary); 14M25 (Secondary) 相似文献