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991.
Guo Qiang Hu Xiao Kui Wu Guo Qiang Wang Nan Nan Duan Xiao Yi Wen Tie Yao Cao Yin Jun Wang Wei Song Qiang Xie Wen Long Huang 《中国化学快报》2012,23(5):515-517
To further explore an efficient modified route for the shift from an antibacterial fluoroquinolone to an antitumor one,mono-Schiff bases 6a-6h related to ciprofloxacin C3 carbonylhydrazone and bis-Schiff bases 4a-4h corresponding to C3/C7 carbonylhydrazone/hydrazone attached on a skeleton of ciprofloquinolone were designed and synthesized,and their in vitro antitumor activity against CHO,HL60,L1210 cells and antibacterial activity against Staphylococcus aureus and Escherichia coli were also reported. 相似文献
992.
993.
Tino Zaehle Pascale Sandmann Jeremy D Thorne Lutz Jäncke Christoph S Herrmann 《BMC neuroscience》2011,12(1):2
Background
Transcranial direct current stimulation (tDCS) is a technique that can systematically modify behaviour by inducing changes in the underlying brain function. In order to better understand the neuromodulatory effect of tDCS, the present study examined the impact of tDCS on performance in a working memory (WM) task and its underlying neural activity. In two experimental sessions, participants performed a letter two-back WM task after sham and either anodal or cathodal tDCS over the left dorsolateral prefrontal cortex (DLPFC). 相似文献994.
Four symmetrical α,α′,δ,δ′-tetramethyl-cucurbit[6]uril-based compounds have been prepared and characterised by X-ray crystallography. Their crystal structures displayed the acetate anion-selective encapsulating capability of symmetrical α,α′,δ,δ′-tetramethyl-cucurbit[6]uril. The host–guest interaction between the symmetrical α,α′,δ,δ′-tetramethyl-cucurbit[6]uril and the acetate anion in aqueous solution has also been observed by variable temperature 1H NMR spectroscopy. 相似文献
995.
Xiaolei Zhang G. P. Petrova Yu. M. Petrusevich I. A. Sergeeva 《Moscow University Physics Bulletin》2012,67(1):66-70
The pH dependence of the intermolecular interaction coefficient of pepsin in an aqueous solution is obtained by using photon-correlation
spectroscopy. The dependence shows a minimum near the isoelectric point (pH 1.6). The dynamic parameters of pepsin macromolecules
in solutions containing various metal ions, including potassium, cobalt, lead, cesium, and rubidium are studied. It is shown
that the addition of these ions causes a decrease of the translational diffusion coefficients. It is found that an increase
in temperature leads to the structural transition of a pure solution of pepsin in water. The activation energy of this transition
is calculated using the Arrhenius law. 相似文献
996.
Besides dispersion engineering, idler-band distributed fiber loss provides a new synthesis freedom to flatten and broaden the gain spectrum for a fiber-optic parametric amplifier. This interesting phenomenon is based on the fact that the power balance between signal and idler is broken by idler loss, which changes the power conversion process in four-wave-mixing. The pump-to-signal conversion efficiency is kept unchanged in spite of the loss. 相似文献
997.
998.
Perfect State Distinguishability and Computational Speedups with Postselected Closed Timelike Curves
Bennett and Schumacher’s postselected quantum teleportation is a model of closed timelike curves (CTCs) that leads to results
physically different from Deutsch’s model. We show that even a single qubit passing through a postselected CTC (P-CTC) is
sufficient to do any postselected quantum measurement with certainty, and we discuss an important difference between “Deutschian”
CTCs (D-CTCs) and P-CTCs in which the future existence of a P-CTC might affect the present outcome of an experiment. Then,
based on a suggestion of Bennett and Smith, we explicitly show how a party assisted by P-CTCs can distinguish a set of linearly
independent quantum states, and we prove that it is not possible for such a party to distinguish a set of linearly dependent
states. The power of P-CTCs is thus weaker than that of D-CTCs because the Holevo bound still applies to circuits using them,
regardless of their ability to conspire in violating the uncertainty principle. We then discuss how different notions of a
quantum mixture that are indistinguishable in linear quantum mechanics lead to dramatically differing conclusions in a nonlinear
quantum mechanics involving P-CTCs. Finally, we give explicit circuit constructions that can efficiently factor integers,
efficiently solve any decision problem in the intersection of NP and coNP, and probabilistically solve any decision problem
in NP. These circuits accomplish these tasks with just one qubit traveling back in time, and they exploit the ability of postselected
closed timelike curves to create grandfather paradoxes for invalid answers. 相似文献
999.
We consider the flow of a viscous incompressible fluid in a pipe when the boundary is a deformable shell of Naghdi type. We
prove that the corresponding system of partial differential equations has a solution when the deformation of the shell is
smooth and small enough. We propose an algorithm that uncouples the unknowns and prove its convergence. 相似文献
1000.
Algirdas Matijoška Tatjana Charkova Zenonas Kuodis Vladislava Voiciuk Olegas Eicher-Lorka 《Central European Journal of Chemistry》2012,10(1):113-120
The synthesis of a new halogenide containing hexyltriethylene glycol chain functionalized with biotin is reported. The general
possibility of this linker to use as the building block for biotinylated compounds syntheses is demonstrated. Two biotinylated
esters with different properties for useful surface modification and as fluorescence probes for proteins marking were synthesized.
The properties of mentioned compounds were investigated by using surface plazmon resonance ellypsometry and fluorescence spectroscopy. 相似文献