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311.
A subset of nonsteroidal anti-inflammatory drugs (NSAIDs) has been shown to preferentially reduce the secretion of the highly amyloidogenic, 42-residue amyloid-beta peptide Abeta42. We found that Rho and its effector, Rho-associated kinase, preferentially regulated the amount of Abeta42 produced in vitro and that only those NSAIDs effective as Rho inhibitors lowered Abeta42. Administration of Y-27632, a selective Rock inhibitor, also preferentially lowered brain levels of Abeta42 in a transgenic mouse model of Alzheimer's disease. Thus, the Rho-Rock pathway may regulate amyloid precursor protein processing, and a subset of NSAIDs can reduce Abeta42 through inhibition of Rho activity.  相似文献   
312.
Analysis of the Doppler tracking data near encounter yields a value for the ratio of the mass of the sun to that of Venus of 408,523.9 +/- 1.2, which is in good agreement with prior determinations based on data from Mariner 2 and Mariner 5. Preliminary analysis indicates that the magnitudes of the fractional differences in the principal moments of inertia of Venus are no larger than 10(-4), given that the effects of gravity-field harmonics higher than the second are negligible. Additional analysis is needed to determine the influence of the higher order harmonics on this bound. Four distinct temperature inversions exist at altitudes of 56, 58, 61, and 63 kilometers. The X-band signal was much more rapidly attenuated than the S-band signal and disappeared completely at 52-kilometer altitude. The nightside ionosphere consists of two layers having a peak density of 10(4) electrons per cubic centimeter at altitudes of 140 and 120 kilometers. The dayside ionosphere has a peak density of 3 X 10(5) electrons per cubic centimeter at an altitude of 145 kilometers. The electron number density observed at higher altitudes was ten times less than that observed by Mariner 5, and no strong evidence for a well-defined plasmapause was found.  相似文献   
313.
Three dogs diagnosed with aspergillosis developed sinonasal tumors several months after successful treatment with topical clotrimazole solution. Chronic rhinosinusitis was also detected in all cases prior to diagnosis of sinonasal tumors. The inflammatory response to Aspergillus, clotrimazole treatment, and chronic inflammation after treatment are discussed as possible neoplastic promoting factors.  相似文献   
314.
In this study, a strain of Anabaena flos-aquae UTEX 1444 was cultivated in six different concentrations of iron (III). Cultures were extracted with organic solvents and analyzed using our dereplication strategy, based on the combined use of high-resolution tandem mass spectrometry and molecular networking. The analysis showed the presence of the siderophores’ family, named synechobactins, only in the zero iron (III) treatment culture. Seven unknown synechobactin variants were present in the extract, and their structures have been determined by a careful HRMS/MS analysis. This study unveils the capability of Anabaena flos-aquae UTEX 1444 to produce a large array of siderophores and may be a suitable model organism for a sustainable scale-up exploitation of such bioactive molecules, for the bioremediation of contaminated ecosystems, as well as in drug discovery.  相似文献   
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