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Improving salinity tolerance in the most widely cultivated cereal, bread wheat (Triticum aestivum L.), is essential to increase grain yields on saline agricultural lands. A Portuguese landrace, Mocho de Espiga Branca accumulates up to sixfold greater leaf and sheath sodium (Na+) than two Australian cultivars, Gladius and Scout, under salt stress in hydroponics. Despite high leaf and sheath Na+ concentrations, Mocho de Espiga Branca maintained similar salinity tolerance compared to Gladius and Scout. A naturally occurring single nucleotide substitution was identified in the gene encoding a major Na+ transporter TaHKT1;5-D in Mocho de Espiga Branca, which resulted in a L190P amino acid residue variation. This variant prevents Mocho de Espiga Branca from retrieving Na+ from the root xylem leading to a high shoot Na+ concentration. The identification of the tissue-tolerant Mocho de Espiga Branca will accelerate the development of more elite salt-tolerant bread wheat cultivars.  相似文献   
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The International Journal of Life Cycle Assessment - Scientific Life Cycle Assessment (LCA) literature provides some examples of LCA teaching in higher education, but not a structured overview of...  相似文献   
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Insulin-like growth factor receptor (IGF-1R) is a growth factor receptor tyrosine kinase that acts as a critical mediator of cell proliferation and survival. Inhibitors of this receptor are believed to provide a new target in cancer therapy. We previously reported an isoquinolinedione series of IGF-1R inhibitors. Now we have identified a series of 3-cyanoquinoline compounds that are low nanomolar inhibitors of IGF-1R. The strategies, synthesis, and SAR behind the cyanoquinoline scaffold will be discussed.  相似文献   
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As part of our research effort to discover B-Raf kinase inhibitors, we prepared a series of C-3 substituted N-(3-(pyrazolo[1,5-a]pyrimidin-7-yl)phenyl)-3-(trifluoromethyl)benzamides. X-ray crystallography studies revealed that one of the more potent inhibitors (10n) bound to B-Raf kinase without forming a hinge-binding hydrogen bond. With basic amine residues appended to C-3 aryl residues, cellular activity and solubility were enhanced over previously described compounds of this class.  相似文献   
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Spirocyclic secondary amine-derived trisubstituted ureas were identified as highly potent, bioavailable and selective soluble epoxide hydrolase (sEH) inhibitors. Despite good oral exposure and excellent ex vivo target engagement in blood, one such compound, rac-1a, failed to lower blood pressure acutely in spontaneously hypertensive rats (SHRs). This study posed the question as to whether sEH inhibition provides a robust mechanism leading to a significant antihypertensive effect.  相似文献   
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The stress hormone corticosterone acts via two receptor types in the brain: the mineralocorticoid (MR) and the glucocorticoid receptor (GR). Both receptors are involved in processing of stressful events. A disbalance of MR:GR functions is thought to promote stress-related disorders. Here we studied the effect of stress on emotional and cognitive behaviors in mice with forebrain-specific inactivation of the MR gene (MRCaMKCre, 4 months old; and control littermates). MRCaMKCre mice responded to prior stress (5 min of restraint) with higher arousal and less locomotor activity in an exploration task. A fear conditioning paradigm allowed assessing in one experimental procedure both context- and cue-related fear. During conditioning, MRCaMKCre mice expressed more cue-related freezing. During memory test, contextual freezing remained potentiated, while control mice distinguished between cue (more freezing) and context episodes (less freezing) in the second memory test. At this time, plasma corticosterone levels of MRCaMKCre mice were 40% higher than in controls. We conclude that control of emotional arousal and adaptive behaviors is lost in the absence of forebrain MR, and thus, anxiety-related responses are and remain augmented. We propose that such a disbalance in MR:GR functions in MRCaMKCre mice provides the conditions for an animal model for anxiety-related disorders.  相似文献   
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For the first time, we measured the home range size and activity pattern of a White-tailed Sea Eagle (WTSE) by GPS telemetry. Positions were recorded three times a day and the activity pattern were continuously recorded by two acceleration sensors. From July to January, we obtained 475 positions and calculated a 95% kernel home range of 4.53 km2 and a 95% minimum convex polygon of 8.22 km2, indicating a rather small area explained by an optimal habitat and by the much more precise location method used here compared to reports in the literature. Biorhythmic analysis of activity data revealed nearly no night-activity, high day-activity with no fixed daily pattern and a strong 24-h period of activity. The stability and synchronisation between the eagle's activity and the environmental 24-h period was evaluated by calculating the degrees of functional coupling (DFC) and the harmonic part (HP). Mostly, DFC was 100% (meaning that the different physiological and behavioural functions are completely synchronised to each other and to the environmental 24-h period) and the few incursions of the DFC we assumed to be caused by clinically relevant lead intoxications. The agonal stage of the WTSE was indicated by a daily decreasing activity level and HPs and highly modified day–night relationship, and decreasing DFCs at the beginning and at the end of dying process, representing changes in the activity structure. The underlying reason for the behavioural changes was found to be a lethal lead intoxication due to an oral ingestion of particles of rifle ammunition. The new technology of a combined GPS receiver and an acceleration sensor allows the automatic measuring of positions and activity of wild animals at a very precise level over prolonged periods which cannot be achieved by manpower.  相似文献   
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