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71.
72.
Anchusa strigosa is a widespread weed in Greece, Syria, Turkey, Lebanon, Israel, Jordan, and Iran. The purpose of this study was to identify the phytochemicals of Anchusa strigose and estimate the pro-wound healing (pro-WH) and antimicrobial activities of its active compounds. An identification of volatile compounds was performed by GC/MS analysis; HPLC, LC-ESI-MS, and MALDI-TOF-MS were also applied. Our results demonstrate that two specific combinations of compounds from A. strigosa extract significantly enhanced WH (p < 0.001). Several flavonoids of the plant extract, including quercetin 3-O-rutinoside, kaempferol, kaempferol 3-O-β-rhamnopyranosyl(1→6)-β-glucopyranoside, and kaempferol 3-O-α-rhamnopyranosyl(1→6)-β-galactopyranoside, were effective against drug-resistant microorganisms. In addition, all the above-mentioned compounds had antibiofilm activity against Escherichia coli and Salmonella enteritidis.  相似文献   
73.
74.
A rigorous examination of the various multiple-quantum magic angle spinning sequences is carried out with reference to sensitivity enhancement in the isotropic dimension and the lineshapes of the corresponding MAS peaks in the anisotropic dimension. An echo efficiency parameter is defined here, which is shown to be an indicator of the performance aspects of the various sequences. This can be used in the design of further new experiments in this field. A consequence of such a systematic analysis has been the combination of a spin-lock pulse for excitation of multiple-quantum coherences and an amplitude-modulated pulse for their conversion to observable single-quantum coherences. This approach has resulted in an improved performance over other sequences with respect to both the anisotropic lineshapes and the isotropic intensities.  相似文献   
75.
Tiltan     
We prove the consistency of ? with the negation of Galvin's property. On the other hand, we show that superclub implies Galvin's property. We also prove the consistency of ?κ+ with sκ>κ+ for a supercompact cardinal κ.  相似文献   
76.
We prove a formula conjectured by Ahrens, Gordon, and McMahon for the number of interior points for a point configuration in bf R d . Our method is to show that the formula can be interpreted as a sum of Euler characteristics of certain complexes associated with the point configuration, and then compute the homology of these complexes. This method extends to other examples of convex geometries. We sketch these applications, replicating an earlier result of Gordon, and proving a new result related to ordered sets. Received September 24, 1998, and in revised form July 6, 1999.  相似文献   
77.
We introduce a model-theoretic characterization of Magidor cardinals, from which we infer that Magidor filters are beyond ZFC-inconsistency.  相似文献   
78.
Periodica Mathematica Hungarica - We study the Galvin property. We show that various square principles imply that the cofinality of the Galvin number is uncountable (or even greater than $$aleph...  相似文献   
79.
Regev  Shimon  Shoshani  Oriel 《Nonlinear dynamics》2020,102(3):1197-1207
Nonlinear Dynamics - We formulate and experimentally validate a theoretical reduced-order model for the transverse galloping of nonlinear structures, namely a pair of identical, parallel-oriented...  相似文献   
80.
A homonuclear dipolar decoupling scheme based on windowed phase-modulated Lee-Goldburg (wPMLG) pulse sequences that causes a"z-rotation" of the spins for high-resolution proton NMR spectroscopy of solids is described and analyzed. This supercycled scheme suppresses the effect of pulse imperfections on the spectra and significantly relaxes the off-resonance dependence of the line-narrowing efficiency and scale factor. This leads to a broad spectral window that is free of artifacts such as zero lines, image peaks, and localized rotor-radio-frequency resonances. High-resolution (1)H spectra and two-dimensional homonuclear (1)H-(1)H correlation spectra of standard amino acids, obtained by a combination of this supercycled scheme with magic angle spinning frequencies up to 25 kHz, are demonstrated.  相似文献   
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