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This paper presents a novel microchip with nanoporous anodic alumina membrane for the study of anti-cancer drug effect of retinoic acid (RA) on human esophageal squamous epithelial KYSE30 cancer cells in vitro with impedance spectroscopy. The impedance experiments with 0.01 M retinoic acid (RA) were explored for the study of anti-cancer drug effects on KYSE30 cancer cells. The impedance was monitored in the time domain at 0.1 Hz. After addition of 0.01 M RA to the cell chip, the impedance magnitude decreased with time from the value with confluent cell layer and returned to the initial base line after around 12 h. The fluorescence experiments testified that this impedance decrease was due to the cell morphology change induced by RA. 相似文献
46.
S.Y. Frankie Mak Gary C.H. Chiang James E.P. Davidson John E. Davies Andrew Ayscough Gilles Pain Jonathan W. Burton Andrew B. Holmes 《Tetrahedron: Asymmetry》2009,20(6-8):921-944
The enantioselective synthesis of a number of simplified analogues of the cytotoxic natural product eleutherobin is reported. 相似文献
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An integral equation formulation for buoyancy-driven convection problems is developed and illustrated. Buoyancy-driven convection in a bounded cylindrical geometry with a free surface is studied for a range of aspect ratios and Nusselt numbers. The critical Rayleigh number, the nature of the cellular motion, and the heat transfer enhancement are computed using linear theory. Green's functions are used to convert the linear problem into linear Fredholm integral equations. Theorems are proved which establish the properties of the eigenvalues and eigenfunctions of the linear integral operator which appears in these equations. 相似文献
48.
K. L. Chow N. K. Mak M. H. Wong X. F. Zhou Y. Liang 《Journal of nanoparticle research》2011,13(3):1007-1017
The objective of this study was to investigate antimicrobial mechanisms of a new catalytic material (charge transfer auto
oxidation–reduction type catalyst, CT catalyst) that may have great potential for application in water/wastewater treatment.
Generation of reactive oxygen species (ROS) in bacteria-free solution, induction of ROS and oxidative damage in bacteria (including
E. coli and S. aureus) were examined for the CT catalyst. The results showed that significantly higher (p < 0.05, via t-test) amount of hydroxyl radicals was generated by the CT catalyst compared with the control, particularly after 6 h of contact
time that more than twice of the amount of the control was produced. The generation of ROS in the bacteria was greater under
higher pH and temperature levels, which closely related with the oxidative damage in cells. The results indicated that CT
catalyst induced oxidative damage in the bacteria might serve as an important mechanism interpreting the anti-microbial function
of the CT catalyst. 相似文献
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Attila Makó Zsolt Rapi György Keglevich Áron Szöllősy László Drahos László Hegedűs Péter Bakó 《Tetrahedron: Asymmetry》2010,21(8):919-925
The chiral monoaza-15-crown-5 lariat ethers annellated to methyl-4,6-O-benzylidene-α-d-glucopyranoside-1 or mannopyranoside 2 have been applied as phase-transfer catalysts in the epoxidation of substituted chalcones and chalcone analogues with tert-butylhydroperoxide resulting in significant asymmetric induction. It was found that the position of the substituents in the aromatic ring of the chalcone had an influence both on the chemical yields and enantiomeric excesses. The lowest enantioselectivities (62–83% ee) were found in the case of ortho-substituted model compounds. The highest ee values (ee of 83–97%) were obtained in the case of para-substituted models. From among the chalcone analogues, the maximum ee (90–92%) was detected for the model compound having α-tert-butyl- and β-aryl groups. Using glucose-based crown ether 1, formation of the (?)-enantiomer was preferred, while applying mannose-based 2 as the catalyst, the (+)-enantiomer was in excess. 相似文献