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Staleva-Musto Hristina Kuznetsova Valentyna Bína David Litvín Radek Polívka Tomáš 《Photosynthesis research》2020,144(2):127-135
Photosynthesis Research - We used ultrafast transient absorption spectroscopy to study excited-state dynamics of two keto-carotenoids, siphonaxanthin and siphonein. These two carotenoids differ in... 相似文献
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The newly established ichnofossil Amanitichnus Omittus ichnogen. et ichnosp. nov. represents a complex burrow system consisting of upward convex conical structures with radiate sculpture, recurring in different stratification levels and connected by a subvertical shaft. The system is interpreted as an intrastratal fodinichnion with some resemblance to epistratal Oldhamia and Glockerichnus. The ichnofossil occurs in the silty Skryje Shale of Middle Cambrian age and is accompanied by common benthic body fossils and by ichnofossils of the Cruziana ichnofacies. 相似文献
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Karel Pomeisl Radek Pohl Robert Snoeck Graciela Andrei 《Nucleosides, nucleotides & nucleic acids》2019,38(2):119-156
Syntheses of α-branched alkyl and aryl substituted 9-[2-(phosphonomethoxy)ethyl]purines from substituted 1,3-dioxolanes have been developed. Key synthetic precursors, α-substituted dialkyl [(2-hydroxyethoxy)methyl]phosphonates were prepared via Lewis acid mediated cleavage of 1,3-dioxolanes followed by reaction with dialkyl or trialkyl phosphites. The best preparative yields were achieved under conditions utilizing tin tetrachloride as Lewis acid and triisopropyl phosphite. Attachment of purine bases to dialkyl [(2-hydroxyethoxy)methyl]phosphonates was performed by Mitsunobu reaction. Final α-branched 9-[2-(phosphonomethoxy)ethyl]purines were tested for antiviral, cytostatic and antiparasitic activity, the latter one determined as inhibitory activity towards Plasmodium falciparum enzyme hypoxanthine-guanine-xanthine phosphoribosyltransfesase. In most cases biological activity was only marginal. 相似文献
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Jindra Windrichova Pavel Broz Radka Fuchsova Ondrej Topolcan Ladislav Pecen Otto Mayer Radek Kucera 《Journal of Medical Biochemistry》2021,40(3):277
BackgroundTo compare four automated immunoassays for the measurement of 25(OH)-vitamin D (25-OHD) and to assess the impact on the results obtained from a healthy population.MethodsWe analysed 100 serum samples on Unicel DxI 800 (Beckman Coulter), Architect i1000 (Abbott), Cobas e411 (Roche) and Liaison XL (DiaSorin). Passing-Bablok regression and Bland-Altman plots were used for method comparison. In order to categorise the obtained values, results were categorised into the following groups: 0-25 nmol/L, 25-50 nmol/L, 50-75 nmol/L and above 75 nmol/L and compared. The percentage of samples below 75 nmol/L, and below 50 nmol/L was then calculated for every method.ResultsAccording to paired comparisons, each method differs from others (p<0.0001) except Cobas vs Architect, which do not show a statistically significant difference (p=0.39). The strongest correlation was found between Liaison and Architect (ρ=0.94, p<0.0001). The percentage of samples below the recommended value of 75 nmol/L were: 70% (Architect), 92% (Liaison), 71% (Cobas) and 89% (Unicel). The percentage of samples below the value of 50 nmol/L were: 17% (Architect), 55% (Liaison), 28% (Cobas) and 47% (Unicel).ConclusionsThe observed differences stem from the use of different analytical systems for 25-OHD concentration analysis and can result in different outcomes. The recommended values should be established for each assay in accordance with the data provided by the manufacturer or in the laboratory, in accordance with proper standardisation. 相似文献
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