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71.
Robert Marc 《Colloid and polymer science》1912,11(4):195-199
Ohne Zusammenfassung 相似文献
72.
Robert Jentzsch 《Acta Mathematica》1916,41(1):219-251
Ohne Zusammenfassung 相似文献
73.
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75.
Robert Fricke 《Mathematische Annalen》1896,47(4):557-563
Ohne Zusammenfassung 相似文献
76.
Robert Fricke 《Mathematische Annalen》1891,38(4):461-476
Ohne Zusammenfassung 相似文献
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79.
Martin L. Kaplan Robert C. Haddon Krishnan Raghavachari Shalini Menezes Frederic C. Schilling Jacques J. Hauser 《Molecular Crystals and Liquid Crystals》2013,570(1):51-66
Four compounds, N,N,N',N'-tetramethyl-p-phenylene diamine, N,N,N',N'-tetramethyl-benzidine, 4,4'-bis(dimethylamino)azobenzene and bis(4-dimethylaminophenylimino)sulfur (BAPIS) were examined electrochemically and spectroscopically. Each was shown to be a fairly good donor forming in its first oxidation state a radical-cation. The latter two materials surprisingly exhibited only single one-electron oxidations. Conformational flexibility about the -NSN- unit was studied by NMR spectroscopy and ab initio molecular orbital theory. The experimental ΔG* for a cis-trans to trans-cis interconversion in BAPIS was found to be 11.9 kcal/mole. The four donors all form 1:1 adducts with TCNQ. The compaction resistances of the complexes have been measured as a function of temperature. Of the four, (BAPIS)(TCNQ) appears to be a one-dimensional material. The other three complexes behave as typical mixed stack organic semiconductors. 相似文献
80.
Natalia Pachura Robert Kupczyski Kamila Lewandowska Maciej Wodarczyk Marta Klemens Piotr Kuropka Renata Nowaczyk Magorzata Krzystek-Korpacka Iwona Bednarz-Misa Tomasz Sozaski Krystyna Pogoda-Sewerniak Antoni Szumny 《Molecules (Basel, Switzerland)》2022,27(11)
Ilex paraguariensis, the holly tree, is a plant with recognized biological properties, whose aqueous infusions are known as “Yerba mate”, that regulate lipid metabolism, reduce obesity, and improve brain stimulation. In the present study, the effect of standardized saponin and terpenoid fractions of a European taxon, Ilex aquifolium, on blood biochemical parameters in a rat model of metabolic disorder, (fa/fa) Zucker, are presented. The profiles of the volatile fractions of two species and six European varieties of Ilex were investigated. After selecting the best variety, the saponin and terpenoid fractions were isolated and standardized, and animals were fed 10 mg kg−1 b.w. for 8 weeks. A statistically significant decrease in liver adiposity was observed, confirmed by histology and quantitative identification (gas chromatography–mass spectrometry analyses of hepatic lipids. RT-qPCR analysis of gene expression in the aorta revealed that the administration of the terpenoid fraction downregulated LOX-1, suggesting a reduction in atherosclerotic stimuli. In addition, a statistically significant reduction (p < 0.05) in PPARγ for the saponin fraction was observed in the liver. The expression of the ACAT-1 gene in the liver, responsible for the formation of cholesterol esters, increased significantly in the group receiving the terpenoid fraction compared to the control, which was also confirmed by the analysis of individual blood biochemical parameters. The opposite effect was observed for saponins. Taking the above into account, it is shown for the first time that Ilex aquifolium can be a source of compounds that positively influence lipid metabolism. 相似文献