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排序方式: 共有749条查询结果,搜索用时 15 毫秒
741.
Appels NM Tung KO Rosing H Schellens JH Beijnen JH 《Biomedical chromatography : BMC》2006,20(2):161-165
Ras proteins play an important role in the development of cancer. Farnesyl transferase inhibitors (FTIs) block the first obligatory post-translational step for activation, prenylation, of Ras proteins. To find new potent FTIs, rapid enzyme activity assays are required to reduce FTI development time. Most assays to date are based on radioactive labelled substrates. We developed a new, in vitro, farnesyl transferase assay based on gradient chromatography coupled to UV detection. Unfarnesylated and farnesylated H-Ras proteins were resolved on a C18 wide-pore HPLC column and their concentrations were determined with use of a calibration curve of unfarnesylated H-Ras. The assay was used to investigate inhibition characteristics of FTIs. The IC50 values of the FTIs L778,123 and SCH66336 were 4.2 nm and 78 microm, respectively. This assay could support the screening and development of FTIs to obtain rapid insights into their inhibitory properties. 相似文献
742.
Wang CF Wang YT Tung PH Kuo SW Lin CH Sheen YC Chang FC 《Langmuir : the ACS journal of surfaces and colloids》2006,22(20):8289-8292
In this study, we report on a simple two-step casting process designed to create a stable superhydrophobic surface. This method possesses the advantages of being both simple and inexpensive as well as utilizing non-fluorine-containing compounds. Most interestingly, we found that the as-prepared surface possesses superhydrophobic properties not only for pure water but also for corrosive water under both acidic and basic conditions. Furthermore, the superhydrophobic polybenzoxazine surfaces had excellent environmental stability with regard to both heating and organic solvent treatment in terms of the contact angle to water. 相似文献
743.
Photooxidation of olefins under oxygen in platinum(II) complex-loaded mesoporous molecular sieves 总被引:1,自引:0,他引:1
Feng K Zhang RY Wu LZ Tu B Peng ML Zhang LP Zhao D Tung CH 《Journal of the American Chemical Society》2006,128(45):14685-14690
Cyclometalated platinum(II) complex has been successfully incorporated into the (3-aminopropyl) triethoxysilane-modified channels of ordered mesoporous silica SBA-15 that has large pore hexagonal channels. Studies on the (1)O(2) generation conclusively demonstrates that the olefins in the nano-channels of SBA-15 can be enriched 8 times higher than those in the homogeneous solution as the diffusion quantum yield of singlet oxygen ((1)O(2)) is assumed to be unit. The platinum(II) complex loaded in the channel of SBA-15 is stable, and the photosensitized oxidation occurs efficiently. No obvious degradation and leaching of photosensitizers is observed even after 10 runs. Only a simple filtration is needed for the recycled use of the expensive noble metal catalysts. This versatile system is a good example of photochemical reactions occurring in the mesoporous silica molecular sieve. SBA-15 not only provides a support for the photosensitizer, but also acts as a nano-reactor to facilitate the photooxidation. 相似文献
744.
Zhao YP Zhao CC Wu LZ Zhang LP Tung CH Pan YJ 《The Journal of organic chemistry》2006,71(5):2143-2146
A simple, highly selective, neutral, fluorescent sensor for fluoride anions is reported. It is based on 2-ureido-4[1H]-pyrimidinone quadruple hydrogen-bonded AADD supramolecular assembly, and its assembling and disassembling processes are also able to respond to external stimuli reversibly. 相似文献
745.
Emilio Defez Antonio Hervás Javier Ibá?ez Michael M. Tung 《Mediterranean Journal of Mathematics》2012,9(4):865-882
This paper deals with the construction of approximate solution of first-order matrix linear differential equations using higher-order matrix splines. An estimation of the approximation error, an algorithm for its implementation and some illustrative examples are included. 相似文献
746.
Effects of Mn Doping on the Optical Properties of Zn2GeO4 Phosphor Prepared Through Co-Precipitation
Lan N. M. C. Hoang Phuong Thang C. X. Kien N. D. T. Pham V.-H. An T. T. Tung N. V. 《Journal of Applied Spectroscopy》2021,88(5):1048-1053
Journal of Applied Spectroscopy - Zn2GeO4 (ZGO) phosphor and Mn-doped ZGO (ZGO:Mn2+) phosphor were successfully synthesized through co-precipitation. Results indicated that Zn ions were... 相似文献
747.
A crystal plasticity model and a homogenization method are used to analyze the local and global mechanical behavior of a ferritic stainless steel. In the first step the material constants are determined based on tensile tests and used to simulate the local deformation behavior on the grain scale in the second step. For that 2D EBSD data are discretized by finite elements. The computed local grain reorientations of three different BCC slip systems are compared to experimental data at the state of 20% elongation. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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