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排序方式: 共有281条查询结果,搜索用时 15 毫秒
71.
72.
E. Benesch P. P. Wiktorow R. Dubrisay M. A. Heath M. W. Bray C. E. Curran C. J. Hansen H. Werres G. Hiller K. Voituret D. Harris F. A. Eustis F. B. Downing L. S. Larsen A. K. Scribner G. Brédemann R. Radeloff A. Ponte A. Grounds W. I. Minajew S. S. Frolow und G. M. Majorow 《Fresenius' Journal of Analytical Chemistry》1935,101(7-8):290-294
Ohne Zusammenfassung 相似文献
73.
Reaction of 1-hydrazinophthalazine with chloroacetyl chloride yields 3-chloromethyl-1,2,4-triazolo-phthalazine. Reaction of this product with the tris tert-butyl ester of DO3A yields a triazolophthalazine appended macrocycle. Hydrolysis and complexation with lanthanide ions gives access to a series of lanthanide complexes (Ln = Nd, Eu, Yb, Er); these are all luminescent and exhibit sensitisation of the lanthanide centre by the chromophore. 相似文献
74.
The technique of ferromagnetic resonance at 23 GHz has been used to determine the first three anisotropy constants of pure Ni down to 4.2K. A temperature and orientation dependent linewidth has also been observed. 相似文献
75.
The orientation of the principal fine structure axes of the major X-trap in benzil neat crystals has been determined relative to the crystalline axes. The best fit of these data was obtained assuming near planarity of the dicarbonyl fragment in the triple state. 相似文献
76.
77.
Starched carbon nanotubes 总被引:9,自引:0,他引:9
Star A Steuerman DW Heath JR Stoddart JF 《Angewandte Chemie (International ed. in English)》2002,41(14):2508-2512
78.
Millward SW Henning RK Kwong GA Pitram S Agnew HD Deyle KM Nag A Hein J Lee SS Lim J Pfeilsticker JA Sharpless KB Heath JR 《Journal of the American Chemical Society》2011,133(45):18280-18288
We describe the use of iterative in situ click chemistry to design an Akt-specific branched peptide triligand that is a drop-in replacement for monoclonal antibodies in multiple biochemical assays. Each peptide module in the branched structure makes unique contributions to affinity and/or specificity resulting in a 200 nM affinity ligand that efficiently immunoprecipitates Akt from cancer cell lysates and labels Akt in fixed cells. Our use of a small molecule to preinhibit Akt prior to screening resulted in low micromolar inhibitory potency and an allosteric mode of inhibition, which is evidenced through a series of competitive enzyme kinetic assays. To demonstrate the efficiency and selectivity of the protein-templated in situ click reaction, we developed a novel QPCR-based methodology that enabled a quantitative assessment of its yield. These results point to the potential for iterative in situ click chemistry to generate potent, synthetically accessible antibody replacements with novel inhibitory properties. 相似文献
79.
Monitoring time‐dependent degradation of phospholipids in sectioned tissues by MALDI imaging mass spectrometry
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Nathan Heath Patterson Aurélien Thomas Pierre Chaurand 《Journal of mass spectrometry : JMS》2014,49(7):622-627
Imaging mass spectrometry (IMS) is useful for visualizing the localization of phospholipids on biological tissue surfaces creating great opportunities for IMS in lipidomic investigations. With advancements in IMS of lipids, there is a demand for large‐scale tissue studies necessitating stable, efficient and well‐defined sample handling procedures. Our work within this article shows the effects of different storage conditions on the phospholipid composition of sectioned tissues from mouse organs. We have taken serial sections from mouse brain, kidney and liver thaw mounted unto ITO‐coated glass slides and stored them under various conditions later analyzing them at fixed time points. A global decrease in phospholipid signal intensity is shown to occur and to be a function of time and temperature. Contrary to the global decrease, oxidized phospholipid and lysophospholipid species are found to increase within 2 h and 24 h, respectively, when mounted sections are kept at ambient room conditions. Imaging experiments reveal that degradation products increase globally across the tissue. Degradation is shown to be inhibited by cold temperatures, with sample integrity maintained up to a week after storage in ?80 °C freezer under N2 atmosphere. Overall, the results demonstrate a timeline of the effects of lipid degradation specific to sectioned tissues and provide several lipid species which can serve as markers of degradation. Importantly, the timeline demonstrates oxidative sample degradation begins appearing within the normal timescale of IMS sample preparation of lipids (i.e. 1–2 h) and that long‐term degradation is global. Taken together, these results strengthen the notion that standardized procedures are required for phospholipid IMS of large sample sets, or in studies where many serial sections are prepared together but analyzed over time such as in 3‐D IMS reconstruction experiments. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
80.
James D. Kubicki Heath D. Watts Zhen Zhao Linghao Zhong 《Cellulose (London, England)》2014,21(2):909-926
Periodic and molecular cluster density functional theory calculations were performed on the Iα (001), Iα (021), Iβ (100), and Iβ (110) surfaces of cellulose with and without explicit H2O molecules of hydration. The energy-minimized H-bonding structures, water adsorption energies, vibrational spectra, and 13C NMR chemical shifts are discussed. The H-bonded structures and water adsorption energies (ΔEads) are used to distinguish hydrophobic and hydrophilic cellulose–water interactions. O–H stretching vibrational modes are assigned for hydrated and dry cellulose surfaces. Calculations of the 13C NMR chemical shifts for the C4 and C6 surface atoms demonstrate that these δ13C4 and δ13C6 values can be upfield shifted from the bulk values as observed without rotation of the hydroxymethyl groups from the bulk tg conformation to the gt conformation as previously assumed. 相似文献