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11.
Marcia I. Dawson Rebecca L.-S. Chan Ian S. Cloudsdale Wesley R. Harris 《Tetrahedron letters》1981,22(29):2739-2742
Tris(catecholcarboxamide) ligands were covalently linked to poly(vinyl amine—vinyl sulfonate sodium salt), and the iron binding capacity of the resultant polymers was found to exceed that of transferrin. 相似文献
12.
Reipa V Mayhew MP Holden MJ Vilker VL 《Chemical communications (Cambridge, England)》2002,(4):318-319
Spectroelectrochemistry measurements are used to demonstrate that active site mutation and binding of an non-natural substrate to P450cam (CYP101) reduces the shift in the redox potential caused by substrate-binding, and thereby results in slower catalytic turnover rate relative to wild-type enzyme with the natural camphor substrate. 相似文献
13.
Marcia Araque-Marin Fabio Bellot Noronha Mickel Capron Franck Dumeignil Michle Friend Egon Heuson Ivaldo Itabaiana Jr. Louise Jalowiecki-Duhamel Benjamin Katryniok Axel Lfberg Sbastien Paul Robert Wojcieszak 《Molecules (Basel, Switzerland)》2022,27(12)
The development of the future French and European bioeconomies will involve developing new green chemical processes in which catalytic transformations are key. The VAALBIO team (valorization of alkanes and biomass) of the UCCS laboratory (Unité de Catalyse et Chimie du Solide) are working on various catalytic processes, either developing new catalysts and/or designing the whole catalytic processes. Our research is focused on both the fundamental and applied aspects of the processes. Through this review paper, we demonstrate the main topics developed by our team focusing mostly on oxygen- and hydrogen-related processes as well as on green hydrogen production and hybrid catalysis. The social impacts of the bioeconomy are also discussed applying the concept of the institutional compass. 相似文献
14.
Fernanda R. Santana Liany Luna-Dulcey Víctor U. Antunes Claudio F. Tormena Marcia R. Cominetti Marcelo C. Duarte 《Natural product research》2020,34(1):102-109
AbstractHyptis pectinata is a herb popularly used in Brazil for the treatment of inflammations, pain, bacterial infections and cancer. In the present study, inflorescences (MPIn), leaves (MPL), branches (MPB), root (MPR) extracts and three compounds isolated from MPIn were assayed against breast tumor cell lines. The structures of the three compounds (pectinolide J, hyptolide and pectinolide E) were determined by means of spectroscopic analysis. Pectinolide J was isolated for the first time. The MPIn, MPL and MPR exhibited specific antiproliferative activity on tumor cell lines when compared to normal cell lines with IC50 of 52.01?±?0.64, 45.91?±?0.02?μg/mL and 82.84?±?0.03?μg/mL, respectively. Although the isolated substances did not present good antiproliferative activity, when the three were associated, a greater biological effect was observed, suggesting a synergistic effect. Hyptolide (5.6?±?0.4?μg/mL) showed IC50 sufficiently low to be considered as a drug prototype. 相似文献
15.
Pedro L. R. Guedes Carolina P. F. Carvalho Adriana A. F. Carbonel Manuel J. Simes Marcelo Y. Icimoto Jair A. K. Aguiar Maria Kouyoumdjian Marcos L. Gazarini Marcia R. Nagaoka 《Molecules (Basel, Switzerland)》2022,27(3)
During liver fibrogenesis, there is an imbalance between regeneration and wound healing. The current treatment is the withdrawal of the causing agent; thus, investigation of new and effective treatments is important. Studies have highlighted the action of chondroitin sulfate (CS) in different cells; thus, our aim was to analyze its effect on an experimental model of bile duct ligation (BDL). Adult Wistar rats were subjected to BDL and treated with CS for 7, 14, 21, or 28 days intraperitoneally. We performed histomorphometric analyses on Picrosirius-stained liver sections. Cell death was analyzed according to caspase-3 and cathepsin B activity and using a TUNEL assay. Regeneration was evaluated using PCNA immunohistochemistry. BDL led to increased collagen content with corresponding decreased liver parenchyma. CS treatment reduced total collagen and increased parenchyma content after 21 and 28 days. The treatment also promoted changes in the hepatic collagen type III/I ratio. Furthermore, it was observed that CS treatment reduced caspase-3 activity and the percentage of TUNEL-positive cells after 14 days and cathepsin B activity only after 28 days. The regeneration increased after 14, 21, and 28 days of CS treatment. In conclusion, our study showed a promising hepatoprotective action of CS in fibrogenesis induced by BDL. 相似文献
16.
Anniversary Dates
75th anniversary of Vladimir K. Baev 相似文献17.
18.
ZDM – Mathematics Education - The focus of this article is the well documented association between low working memory capacity and difficulty with mathematical word-problem solving. We begin... 相似文献
19.
In several applications, underestimation of functions has proven to be a helpful tool for global optimization. In protein–ligand
docking problems as well as in protein structure prediction, single convex quadratic underestimators have been used to approximate
the location of the global minimum point. While this approach has been successful for basin-shaped functions, it is not suitable
for energy functions with more than one distinct local minimum with a large magnitude. Such functions may contain several
basin-shaped components and, thus, cannot be underfitted by a single convex underestimator. In this paper, we propose using
an underestimator composed of several negative Gaussian functions. Such an underestimator can be computed by solving a nonlinear
programming problem, which minimizes the error between the data points and the underestimator in the L
1 norm. Numerical results for simulated and actual docking energy functions are presented. 相似文献
20.