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991.
Galina A. Bikzhanova Irina S. Toulokhonova Stephen Gately Robert West 《Silicon Chemistry》2007,3(3-4):209-217
Synthesis, spectroscopic characterization and in vitro pharmacological and cancer cell growth inhibitory activity studies of new silicon-containing compounds based on the indomethacin
scaffold are now reported. Amidation of the indomethacin carboxylate group using amino-functional silanes generated a series
of novel lipophilic derivatives of indomethacin. The pharmacological activity of these derivatives tested against human recombinant
cyclooxygenase-1 and 2 demonstrated that the silicon-containing derivatives are cyclooxygenase-2 (COX-2) selective. The silicon-containing
amides of indomethacin demonstrated in vitro growth inhibitory activity against human MiaPaCa-2 pancreatic carcinoma cells at low μM concentrations. The 3a and 3c derivatives exhibited the most potent in vitro antiproliferative activity, with IC50 <6.0 μM, compared to unmodified indomethacin having an IC50100 μM.
We dedicate this paper to Prof. Mitsuo Kira, outstanding organosilicon chemist and valued friend. 相似文献
992.
《Surface and interface analysis : SIA》2005,37(1):90-91
This International Standard specifies a secondary ion mass spectrometric method using magnetic‐sector or quadrupole mass spectrometers for depth profiling of boron in silicon, and using stylus profilometry or optical interferometry for depth calibration. This method is applicable to single‐crystal, polycrystal or amorphous silicon specimens with boron atomic concentrations between 1 × 1016 and 1 × 1020 atoms cm?3, and to the crater depth of 50 nm or deeper. Optical interferometry is generally applicable to crater depths in the range 0.5–5 µm. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Luminescent Thermometers: A New Generation of Primary Luminescent Thermometers Based on Silicon Nanoparticles and Operating in Different Media (Part. Part. Syst. Charact. 10/2016)
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995.
Frontispiece: Cationic Five‐Coordinate Bis(guanidinato)silicon(IV) Complexes with SiN4El Skeletons (El=S,Se): “Heterolytic Activation” of S−S and Se−Se Bonds
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996.
Anchoring transitions were observed of nematic liquid crystal (LC) mixtures on obliquely evaporated SiO x by varying the relative abundance of two components in the mixture. Of these two components, one has a longitudinal cyano group and another has lateral cyano groups. It was also found that both temperature and SiO x thickness variations are able to shift the anchoring transitions. The anchoring on SiO x has two origins: long‐range van der Waals potential and short‐range surface interactions. Since the two origins have opposite preference in LC director orientation the observed transition is caused by the change of their relative strength. Thermal absorption–desorption of molecules on SiO x surface is important in determining the strength of short‐range interactions, whereas the layer thickness and optical properties of SiO x are dependent on the van der Waals potential. Based on previous work by de Gennes we propose a model to describe the observed phenomenon. 相似文献
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