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511.
Cinta Llibre Elisabet Zamora Àngel Caballero Josep Lupón Alba Ros Nuria Benito 《Biomarkers》2016,21(3):225-232
Context: Prognostic value of ST2 levels and dynamics has not been investigated in acute heart failure (AHF) using prospective real-life measurements.Objective: The objective of this study is to investigate the prognostic value of ST2 in AHF.Methods: ST2 levels were determined at admission (n?=?182) and discharge (n?=?85). Primary endpoint was the composite of all-cause death and HF rehospitalisation at one year.Results: Discharge ST2 (HR 2.42 [95% CI 1.46–4], p?=?0.001) and ΔST2 (HR 2.32 [95% CI 1.21–4.57], p?=?0.01) but not admission ST2, remained independently prognostic for the primary endpoint after comprehensive multivariable adjustment. ST2 significantly improved prognosis stratification on top of clinical variables and NTproBNP.Conclusions: Routine clinical use of discharge ST2 and ST2 dynamics provide independent prognostic information. 相似文献
512.
A filter hybridization method employing bacterial samples and [125I]labeled chromosomal DNA as a probe was used for DNA-DNA hybridization. It was found that the hybrids had a thermal melting temperature very similar to that of duplexes formed by purified filterbound DNA. The difference in thermal denaturation midpoint between homologous and heterologous duplexes was determined for a number of strains ofAcinetobacter spp. andEnterobacter agglomerans. A comparison with the corresponding data obtained by the hydroxyapatite method showed good correlation between the two methods. The use of bacterial samples in filter hybridization omits the time-consuming DNA preparation procedure necessary for traditional DNA-DNA hybridization procedures. A simplified, two-step elution procedure is suggested for processing large numbers of strains. 相似文献
513.
Elisabet Boija 《生物化学与生物物理学报:生物膜》2006,1758(5):620-626
In order to elucidate the modes of interaction between lignin precursors and membranes, we have studied the influence of temperature, lipid composition and buffer composition on the partitioning of monolignol and dilignol model substances into phospholipid bilayers. The partitioning was determined by immobilized liposome chromatography, which is an established method for studies of pharmaceutical drugs but a new approach in studies of lignin synthesis. The temperature dependence of the retention and the effect of a high ammonium sulfate concentration in the mobile phase demonstrated that the interaction involved both hydrophobic effects and polar interactions. There was also a good correlation between the partitioning and the estimated hydrophobicity, in terms of octanol/water partitioning. The partitioning behavior of the model substances suggests that passive diffusion over the cell membrane is a possible transport route for lignin precursors. This conclusion is strengthened by comparison of the present results with the partitioning of pharmaceutical drugs that are known to pass cell membranes by diffusion. 相似文献
514.
515.
Rakel Gudmundsdottir Gisli Mar Gislason Snaebjorn Palsson Jon S. Olafsson Anders Schomacker Nikolai Friberg Guy Woodward Elisabet R. Hannesdottir Brian Moss 《Aquatic Botany》2011,95(4):278-286
Eight adjacent sub-arctic streams with consistently different temperatures but broadly similar chemistry, other than some differences in conductivity and linked pH, were used to investigate effects of temperature regime on the structure of primary producer communities. Grazing by invertebrates was also taken into account to detect possible effects on the primary producers.The moss species Fontinalis antipyretica Hedw. (Bryophyta) was only observed in the warmer streams and its cover was positively linked with temperature. The liverwort Jungermannia exsertifolia (Steph.) was absent from the warmer streams and scarce in the colder streams. The biomass of F. antipyretica was inversely correlated with concentration of epilithic chlorophyll a, possibly due to shading from the bryophyte and/or competition between algae and bryophytes for nutrients. Epilithic algae and bryophyte biomass were not related to density of the main grazer, Radix peregra Müller (Gastropoda).A high biovolume of green algae (Chlorophyta) occurred in all streams. The biovolume Cyanobacteria was greatest in the coldest stream and in the two intermediately warm streams. Diatom biovolume was low compared with the biovolumes of Cyanobacteria and green algae in all streams, except in the two warmest streams, where the highest biovolume of diatom occurred.Regularized Canonical Correlation Analysis (RCCA) classification based on all primary producer assemblages and invertebrates indicated that warm streams (16.7–22.2 °C) were similar to each other. It also showed that the colder streams (6.6–13.2 °C) were different from the warmer streams and from each other because of differences in conductivity. Temperature and conductivity were the most influential variables in determining overall stream diversity. 相似文献