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211.
Meerovich IG Jerdeva V Derkacheva VM Meerovich GA Lukyanets EA Kogan EA Savitsky AP 《Journal of photochemistry and photobiology. B, Biology》2005,80(1):57-64
The photodynamic activity of dibiotinylated aluminum sulfophthalocyanine was studied in vitro and in vivo. Dibiotinylated aluminum sulfophthalocyanine provided enhanced phototoxic action on OAT-75 cell monolayers as compared with the parent drug. Photodynamic therapy of mice with Ehrlich carcinoma using dibiotinylated aluminum sulfophthalocyanine (0.25 mg/kg) resulted in enhanced inhibition of tumor growth, pronounced vascular damage (thrombosis and destruction of vascular walls) and eventual tumor necrosis. 相似文献
212.
Sergii Afonin Alexander Frey Sybille Bayerl Dahlia Fischer Parvesh Wadhwani Sevil Weinkauf Anne S Ulrich 《Chemphyschem》2006,7(10):2134-2142
Cell-penetrating peptides (CPPs) are short polycationic sequences that can translocate into cells without disintegrating the plasma membrane. CPPs are useful tools for delivering cargo, but their molecular mechanism of crossing the lipid bilayer remains unclear. Here we study the interaction of the HIV-derived CPP TAT (48-60) with model membranes by solid-state NMR spectroscopy and electron microscopy. The peptide induces a pronounced isotropic (31)P NMR signal in zwitterionic DMPC, but not in anionic DMPG bilayers. Octaarginine and to a lesser extent octalysine have the same effect, in contrast to other cationic amphiphilic membrane-active peptides. The observed non-lamellar lipid morphology is attributed to specific interactions of polycationic peptides with phosphocholine head groups, rather than to electrostatic interactions. Freeze-fracture electron microscopy indicates that TAT(48-60) induces the formation of rodlike, presumably inverted micelles in DMPC, which may represent intermediates during the translocation across eukaryotic membranes. 相似文献
213.
Alexander V. Stepakov Jörg Magull Galina L. Starova Rafael R. Kostikov 《Tetrahedron》2006,62(15):3610-3618
Treatment of substituted 1,3-dithiolanes and 1,3-oxathiolanes with methyl diazoacetate in the presence of Rh2(OAc)4 effects ring expansion to the corresponding substituted 1,4-dithiane-2-carboxylates and 1,4-oxathiane-3-carboxylates. The sulfur ylides initially generated in these reactions undergo Stevens rearrangement in competition with both [2,3]-C-C-sigmatropic rearrangement and intramolecular fragmentation. In the case of 2-styryl-substituted 1,3-oxathiolane and 1,3-dithiolane, ring expansion on one-, three- and four-carbons subsequently takes place. 相似文献
214.
Haran TE Cohen I Spasic A Yang K Mohanty U 《Journal of the American Chemical Society》2003,125(37):11160-11161
We have developed a quantitative predictive model capable of describing the dynamics of migration of intrinsically curved DNA fragments on polyacrylamide gels. The model takes into account structural features of DNA, end-to-end distance, screening of hydrodynamic interactions, ionic strength of buffer, electrostatic persistence length, structural fluctuations of the macromolecule, counter condensation, and variation of dielectric constant and viscosity of water with MPD. In doing so, we have also addressed a decade old issue on the effect of the organic solvent 2-methyl-2,4-pentanediol on gel migration of phased A-tracts. We show here that A-tract-solvent interactions are less favored compared with A-tract-A-tract and solvent-solvent interactions. 相似文献
215.
Turan Ozturk Andrey S. Klymchenko Sule Oncul Sule Taskiran F. Betul Kaynak Alexander P. Demchenko 《Tetrahedron》2007,63(41):10290-10299
Nine new 3-hydroxyflavone derivatives as fluorescent molecular sensors having two well-separated emission bands were synthesized. These sensors can occupy well-determined locations and orientations in macromolecular ensembles, such as micelles due to their finely-tuned designs. These polarity-sensitive dyes can incorporate into the anhydrous hydrophobic core of aqueous micelles. 相似文献
216.
Lytchak Alexander Petrunin Anton 《Journal of Optimization Theory and Applications》2022,194(2):636-642
Journal of Optimization Theory and Applications - We show that cyclic products of projections onto convex subsets of Hadamard spaces can behave in a more complicated way than in Hilbert spaces,... 相似文献
217.
Let (E, (ie63-01),) be a halfordered plane and call
convex if M contains for any two points a,bM all pointsx between a and b. It is shown that segments [a,b] are convex if and only if (E, (ie63-02)) is the affine plane of order 3, (E, (ie63-03),) is an ordered plane or is near-trivial.
Herrn Professor Johannes Böhm zum 70. Geburtstag gewidmet 相似文献
Herrn Professor Johannes Böhm zum 70. Geburtstag gewidmet 相似文献
218.
We prove two new upper bounds on the size of binary codes with a minimum distance of three, namelyA(10, 3)76 andA(11, 3)152. 相似文献
219.
Balest R Cho K Ford WT Lohner M Park H Rankin P Smith JG Alexander JP Bebek C Berger BE Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Dickson M Drell PS Dumas DJ Ehrlich R Elia R Gaidarev P Garcia-Sciveres M Gittelman B Gray SW Hartill DL Heltsley BK Henderson S Jones CD Jones SL Kandaswamy J Katayama N Kim PC Kreinick DL Lee T Liu Y Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E Patterson JR Peterson D Riley D Soffer A Avery P Freyberger A Lingel K Prescott C 《Physical review letters》1995,75(21):3809-3813
220.
Artuso M Gao M Goldberg M He D Horwitz N Moneti GC Mountain R Muheim F Mukhin Y Playfer S Rozen Y Stone S Xing X Zhu G Bartelt J Csorna SE Egyed Z Jain V Gibaut D Kinoshita K Pomianowski P Barish B Chadha M Chan S Cowen DF Eigen G Miller JS O'Grady C Urheim J Weinstein AJ Würthwein F Asner DM Athanas M Bliss DW Brower WS Masek G Paar HP Gronberg J Korte CM Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Qiao C Richman JD Roberts D Ryd A Tajima H Witherell MS Balest R Cho K 《Physical review letters》1995,75(5):785-789