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951.
Thin and transparant single crystalline plates of calcium tungstate have been grown by using the method of isothermal flux evaporation at 840°C. The floating plates exhibited spiral depression on their top as-grown surfaces as revealed by high resolution (20 A°) electron-optical plant. It is believed that the spiral pattern results from thermal etching at the sites of helical dislocations.  相似文献   
952.
Specific sensing and functional tuning of nucleic acid secondary structures remain less explored to date. Herein, we report a thiazole polyamide TPW that binds specifically to c-KIT1 G-quadruplex (G4) with sub-micromolar affinity and ∼1 : 1 stoichiometry and represses c-KIT proto-oncogene expression. TPW shows up to 10-fold increase in fluorescence upon binding with c-KIT1 G4, but shows weak or no quantifiable binding to other G4s and ds26 DNA. TPW can increase the number of G4-specific antibody (BG4) foci and mark G4 structures in cancer cells. Cell-based assays reveal that TPW can efficiently repress c-KIT expression in leukemia cells via a G4-dependent process. Thus, the polyamide can serve as a promising probe for G-quadruplex recognition with the ability to specifically alter c-KIT oncogene expression.  相似文献   
953.
In the past decade, innovative protein therapies and bio-similar industries have grown rapidly. Additionally, ionic liquids (ILs) have been an area of great interest and rapid development in industrial processes over a similar timeline. Therefore, there is a pressing need to understand the structure and function of proteins in novel environments with ILs. Understanding the short-term and long-term stability of protein molecules in IL formulations will be key to using ILs for protein technologies. Similarly, ILs have been investigated as part of therapeutic delivery systems and implicated in numerous studies in which ILs impact the activity and/or stability of protein molecules. Notably, many of the proteins used in industrial applications are involved in redox chemistry, and thus often contain metal ions or metal-associated cofactors. In this review article, we focus on the current understanding of protein structure-function relationship in the presence of ILs, specifically focusing on the effect of ILs on metal containing proteins.  相似文献   
954.
Chromatographia - A novel, dual gradient LC method for quantification of vardenafil (VR) and its degradant products was developed with a multivariate approach. In the QbD approach, primary...  相似文献   
955.
JPC – Journal of Planar Chromatography – Modern TLC - A precise, robust and accurate high-performance thin-layer chromatography (HPTLC) method has been developed for the simultaneous...  相似文献   
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958.
Previously we demonstrated a method, Quantized Surface Complementarity Diversity (QSCD), of defining molecular diversity by measuring shape and functional complementarity of molecules to a basis set of theoretical target surfaces [Wintner E.A. and Moallemi C.C., J. Med. Chem., 43 (2000) 1993]. In this paper we demonstrate a method of mapping actual protein pockets to the same basis set of theoretical target surfaces, thereby allowing categorization of protein pockets by their properties of shape and functionality. The key step in the mapping is a `dissection' algorithm that breaks any protein pocket into a set of potential small molecule binding volumes. It is these binding volumes that are mapped to the basis set of theoretical target surfaces, thus measuring a protein pocket not as a single surface but as a collection of molecular recognition environments.  相似文献   
959.
A synthesis of terfenadine carboxylate, 1, a metabolite of terfenadine 2, is described. In the key step, the sodium salt of 2-(4-bromophenyl)-2-methylpropionic acid, 7, was lithiated via a metal-halogen exchange using t-BuLi and subsequently condensed with 4-[4-(hydroxydiphenylmethylpiperidin-1-yl]butyraldehyde, 5, to afford terfenadine carboxylate, 1.  相似文献   
960.
Yatin  N.Patel  Manish  P.Patel 《中国化学快报》2013,24(11):1005-1007
The objective of this research is to utilize a new poly[N,N-diallyl pyrrolidinium bromide-co-N,Ndimethyl acrylamide-co-acrylic acid sodium salt]superabsorbent hydrogel(SAH)for the removal of two anionic dyes,e.g.,Reactive Red 5B(RR5B)and Reactive Orange M2R(ROM2R),from water.The SAH was characterized by swelling in water,FTIR,TGA and SEM.The SAH DDA6showed good swelling property and thermal stability.We have also investigated the parameters affecting dye adsorption such as pH,adsorbent dose,adsorption rate and initial dye concentration.The experimental data were also analyzed by applying the well known Langmuir and Freundlich isotherm models.  相似文献   
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