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51.
Chad?A?Dickey Marcia?N?Gordon Donna?M?Wilcock Donna?L?Herber Melissa?J?Freeman Dave?MorganEmail author 《BMC neuroscience》2005,6(1):7
Background
The pathology of Alzheimer's disease (AD) is comprised of extracellular amyloid plaques, intracellular tau tangles, dystrophic neurites and neurodegeneration. The mechanisms by which these various pathological features arise are under intense investigation. Here, expanding upon pilot gene expression studies, we have further analyzed the relationship between Na+/K+ ATPase and amyloid using APP+PS1 transgenic mice, a model that develops amyloid plaques and memory deficits in the absence of tangle formation and neuronal or synaptic loss. 相似文献52.
[reaction: see text] Nucleophile-loaded peptides have been evaluated as catalysts for the desymmetrization of glycerol derivatives through an enantioselective acylation process. Enantiomeric excesses of up to 97% have been obtained for the monoacylated products. A range of other substrates have been examined that shed light on the mechanistic basis of the desymmetrizations. 相似文献
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Brown AM Ovchinnikov MV Stern CL Mirkin CA 《Journal of the American Chemical Society》2004,126(44):14316-14317
A novel reaction involving the halide-induced rearrangement of ligands within supramolecular Rh(I) complexes containing hemilabile ligands is presented. Three analogous bis- and trishemilabile ligands have been synthesized to construct bi- and trimetallic Rh(I) macrocyclic complexes. An intentionally added halide source results in the formal rotation of only one hemilabile ligand along the axis that is perpendicular to the plane defined by the aryl backbone of the hemilabile ligands. X-ray structures, as determined by X-ray crystallography, of key intermediates and products are presented. 相似文献
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Trifluoroacetic acid efficiently catalyzes Prins cyclizations of enol ethers 8 to provide tetrahydropyrans 9 and 10. These tetrahydropyrans are isolated with combined yields of 42-85% and stereoselectivities at C(4) ranging from 95:5 to 50:50 depending on the nature of the substituent R. Unique byproducts of these cyclizations that reveal the presence of underlying equilibria have been isolated and identified. [reaction: see text] 相似文献
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Nichole Cates Miller Roman Gysel Chad E. Miller Eric Verploegen Zach Beiley Martin Heeney Iain McCulloch Zhenan Bao Michael F. Toney Michael D. McGehee 《Journal of Polymer Science.Polymer Physics》2011,49(7):499-503
Polymer:fullerene blends have been widely studied as an inexpensive alternative to traditional silicon solar cells. Some polymer:fullerene blends, such as blends of poly(2,5‐bis(3‐tetradecylthiophen‐2‐yl)thieno[3,2‐b]thiophene (pBTTT) with phenyl‐c71‐butyric acid methyl ester (PC71BM), form bimolecular crystals due to fullerene intercalation between the polymer side chains. Here we present the determination of the eutectic pBTTT:PC71BM phase diagram using differential scanning calorimetry (DSC) and two‐dimensional grazing incidence X‐ray scattering (2D GIXS) with in‐situ thermal annealing. The phase diagram explains why the most efficient pBTTT:PC71BM solar cells have 75–80 wt % PC71BM since these blends lie in the center of the only room‐temperature phase region containing both electron‐conducting (PC71BM) and hole‐conducting (bimolecular crystal) phases. We show that intercalation can be suppressed in 50:50 pBTTT:PC71BM blends by using rapid thermal annealing to heat the blends above the eutectic temperature, which forces PC71BM out of the bimolecular crystal, followed by quick cooling to kinetically trap the pure PC71BM phase. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
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