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511.
Zhu Guorong Ebbing Alexander Bouma Tjeerd J. Timmermans Klaas R. 《Journal of applied phycology》2021,33(4):2471-2483
Journal of Applied Phycology - Morphology and physiology are two key aspects of the adaptation of kelp to varying environments. Some of these kelp responses to co-occurring highly hydrodynamic... 相似文献
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A facile method for the rapid synthesis of benzoacridines has been described. This protocol promoted by p-toluenesulfonic acid starts from aromatic aldehydes and N-phenyl naphthylamines, affording a variety of benzoacridines in 30–90 % yields under metal-free conditions. The present approach involves a cascade of condensation, Friedel-Crafts alkylation, annulation and dehydroaromatization in one pot. 相似文献
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The GAF domain of phytochrome is essential for photoconversion and signal transduction. In gymnosperms, it exists in all members of the phytochrome family that experience gene duplication. Maximum-likelihood models of codon substitution can provide a framework for constructing likelihood ratio tests of changes in selective pressure and make clear predictions about patterns of genetic change following gene duplication. In this study, 68 gymnosperm GAF sequences were analyzed to identify lineages and sites under positive selection. Our results indicate that (1) positive selection at a few sites (3.6%), rather than relaxation of selective constraints, has played a major role in the evolution of the gymnosperm GAF domain; (2) strong positive selective pressure tends to occur in the recent PHYP lineages of cogeneric species, but is absent in old lineages consisting of distantly related species; and (3) the selective pressure indicated by the ω ratio varies greatly among lineages and sites in the GAF domain. 相似文献
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Changqin Jing Xiaoyu Li Jihong Zhang Jianji Wang 《Journal of biochemical and molecular toxicology》2013,27(6):330-336
This study aims to evaluate the cytotoxicity and responses of the cellular antioxidant system of 1‐octyl‐3‐methylimidazolium chloride ([C8mim][Cl]) on human hepatocarcinoma QGY‐7701 cells. The results show that [C8mim][Cl] can inhibit QGY‐7701 cell growth and decrease their viabilities in a dose‐dependent manner. The results also reveal that [C8mim][Cl] exposure can induce apoptosis in the [C8mim][Cl]‐treated QGY‐7701 cells. In addition, the results of biochemical assays show that [C8mim][Cl] exposure causes overproduction of reactive oxygen species (ROS), inhibits superoxide dismutase (SOD) and catalase (CAT) activities, decreases reduced glutathione (GSH) content, and increases the cellular malondialdehyde (MDA) level. These results suggest that ROS‐mediated oxidative stress may be responsible for the apoptosis induced by [C8mim][Cl] in QGY‐7701 cells. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:330‐336, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21495 相似文献
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This work presents here a new fundamental strategy for bio-converting Kraft lignin (KL) into useful products. Cupriavidus basilensis B-8 (here after B-8) was able to use KL as the sole carbon source. Fully 41.5% of lignin, 37.7% of total carbon (TC) and 43.0% of color were removed after 7 days of incubation. At the same time, lignin was depolymerized into small fragments, which was confirmed by scanning electron microscopy (SEM) and gel permeation chromatography (GPC). Bacterial biomass accumulated to 735.6 mg/L at the initial KL concentration of 5 g L−1, and the corresponding volumetric productivity of polyhydroxyalkanoate (PHA) was 128 mg/L. PHA productivity was significantly improved through fed batch fermentation and reached to 319.4 mg/L. GC–MS analysis showed that PHA polymer was composed of three basic monomers: 98.3 mol% of (S)-3-hydroxy-butanoic acid (S3HB), 1.3 mol% of ®-3-hydroxybutyric acid (R3HB) and 0.4 mol% of 3-hydroxy-butanoic acid (3HB). 相似文献
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