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排序方式: 共有262条查询结果,搜索用时 47 毫秒
111.
112.
Deep Prakash Akhil MS Buddidhathi Radhika Radhika Venkatesan Sreekanth H Chalasani Varsha Singh 《The EMBO journal》2021,40(13)
Animals possess conserved mechanisms to detect pathogens and to improve survival in their presence by altering their own behavior and physiology. Here, we utilize Caenorhabditis elegans as a model host to ask whether bacterial volatiles constitute microbe‐associated molecular patterns. Using gas chromatography–mass spectrometry, we identify six prominent volatiles released by the bacterium Pseudomonas aeruginosa. We show that a specific volatile, 1‐undecene, activates nematode odor sensory neurons inducing both flight and fight responses in worms. Using behavioral assays, we show that worms are repelled by 1‐undecene and that this aversion response is driven by the detection of this volatile through AWB odor sensory neurons. Furthermore, we find that 1‐undecene odor can induce immune effectors specific to P. aeruginosa via AWB neurons and that brief pre‐exposure of worms to the odor enhances their survival upon subsequent bacterial infection. These results show that 1‐undecene derived from P. aeruginosa serves as a pathogen‐associated molecular pattern for the induction of protective responses in C. elegans. 相似文献
113.
Single visit endodontics offers many advantages over multi visit treatment. Therefore, it is of interest to assess the preference of single visit over multiple visit root canals. We used 86,000 patient records and selected 9017 records matching the inclusion criteria for the analysis using statistical tools (Chi square test at p value <0.05). Data shows that people between 26 to 45 years are often affected with dental caries. Available data is biased towards multi visits rather than single visit regardless number of canals. 相似文献
114.
Elizabeth R. Selig Catherine Longo Benjamin S. Halpern Benjamin D. Best Darren Hardy Cristiane T. Elfes Courtney Scarborough Kristin M. Kleisner Steven K. Katona 《PloS one》2013,8(4)
People value the existence of a variety of marine species and habitats, many of which are negatively impacted by human activities. The Convention on Biological Diversity and other international and national policy agreements have set broad goals for reducing the rate of biodiversity loss. However, efforts to conserve biodiversity cannot be effective without comprehensive metrics both to assess progress towards meeting conservation goals and to account for measures that reduce pressures so that positive actions are encouraged. We developed an index based on a global assessment of the condition of marine biodiversity using publically available data to estimate the condition of species and habitats within 151 coastal countries. Our assessment also included data on social and ecological pressures on biodiversity as well as variables that indicate whether good governance is in place to reduce them. Thus, our index is a social as well as ecological measure of the current and likely future status of biodiversity. As part of our analyses, we set explicit reference points or targets that provide benchmarks for success and allow for comparative assessment of current conditions. Overall country-level scores ranged from 43 to 95 on a scale of 1 to 100, but countries that scored high for species did not necessarily score high for habitats. Although most current status scores were relatively high, likely future status scores for biodiversity were much lower in most countries due to negative trends for both species and habitats. We also found a strong positive relationship between the Human Development Index and resilience measures that could promote greater sustainability by reducing pressures. This relationship suggests that many developing countries lack effective governance, further jeopardizing their ability to maintain species and habitats in the future. 相似文献
115.
An optimally functional brain requires both excitatory and inhibitory inputs that are regulated and balanced. A perturbation in the excitatory/inhibitory balance—as is the case in some neurological disorders/diseases (e.g. traumatic brain injury Alzheimer’s disease, stroke, epilepsy and substance abuse) and disorders of development (e.g. schizophrenia, Rhett syndrome and autism spectrum disorder)—leads to dysfunctional signaling, which can result in impaired cognitive and motor function, if not frank neuronal injury. At the cellular level, transmission of glutamate and GABA, the principle excitatory and inhibitory neurotransmitters in the central nervous system control excitatory/inhibitory balance. Herein, we review the synthesis, release, and signaling of GABA and glutamate followed by a focused discussion on the importance of their transport systems to the maintenance of excitatory/inhibitory balance. 相似文献
116.
Marc B. Rietberg Erwin E. H. van Wegen Isaline C. J. M. Eyssen Gert Kwakkel the MS study group 《PloS one》2014,9(9)
Background
Several rehabilitation programmes aim at reducing the impact of fatigue in MS patients. Acute and chronic fatigue should require different management.Objectives
To assess the effects of individually tailored, multidisciplinary outpatient rehabilitation (MDR) on chronic fatigue.Methods
Forty-eight ambulatory MS patients with chronic fatigue were randomized to MDR or to MS–nurse consultation. Fatigue was assessed by the Checklist Individual Strength (CIS-20R). Secondary outcomes included the Modified Fatigue Impact Scale, Fatigue Severity Scale, Functional Independence Measure, Disability and Impact Profile (DIP), Multiple Sclerosis Impact Scale and the Impact on Participation and Autonomy (IPA).Results
The primary outcome measure CIS-20R overall score showed no significant differences between groups at 12 weeks (P = 0.39) and 24 weeks follow-up (P = 0.14), nor for subscales (t = 12 and t = 24, 0.19≤P≤0.88). No significant within-group effects were found for both groups with respect to the primary (0.57≤p≤0.97) and secondary (0.11≤p≤0.92) outcome measures from baseline to 12 or 24 weeks.Conclusion
Multidisciplinary rehabilitation was not more effective in terms of reducing self-reported fatigue in MS patients compared to MS-nurse consultation. Our results suggest that chronic fatigue in patients with MS may be highly invariant over time, irrespective of interventions.Trial Registration
controlled-trials.com ISRCTN05017507 相似文献117.
Levinger I Selig S Goodman C Jerums G Stewart A Hare DL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(8):2328-2333
Depression is more prevalent in obese individuals and those with diabetes, compared to the general population. This study examined the effect of resistance training on depressed mood in individuals with high (HiMF, n ≥ 2) and low (LoMF, n ≤ 1) numbers of risk factors for metabolic syndrome and type 2 diabetes. The primary hypothesis was that resistance training would significantly reduce depressed mood, as measured by the Cardiac Depression Scale (CDS), in individuals with HiMF. Fifty-five middle-aged volunteers (50.8 ± 0.9 years, mean ± SEM) from the general community participated in the study. After initial allocation to HiMF or LoMF, participants were randomly allocated to 4 groups, HiMF training (HiMFT), HiMF control (HiMFC), LoMF training (LoMFT), and LoMF control (LoMFC). Participants underwent resistance training involving major muscle groups on 3 d·wk(-1) for 10 weeks. Before and after interventions (training or control), participants completed the CDS to assess change in the level of depressed mood. Following resistance training, the CDS score of the HiMFT group was reduced by -14.8 ± 4.9 points on the CDS, a significant improvement in comparison to both baseline (p = 0.01) and HiMFC (p = 0.049) values. No significant change was observed for LoMFT. In the HiMF group only, the percent change in relative muscle strength was correlated with the Δ change in CDS; r = -0.46, p = 0.008. Resistance exercise training programs that consist 7 exercises for the major muscle groups at both low-moderate and moderate-high intensities appear to alleviate depressed mood in individuals with clusters of metabolic risk factors. 相似文献
118.
119.
Brunecky R Selig MJ Vinzant TB Himmel ME Lee D Blaylock MJ Decker SR 《Biotechnology for biofuels》2011,4(1):1
The glycoside hydrolase family 5 endocellulase, E1 (Cel5A), from Acidothermus cellulolyticus was transformed into both Nicotiana tabacum and Zea mays with expression targeted to the cell wall under a constitutive promoter. Here we explore the possibility that in planta expression of endocellulases will allow these enzymes to access their substrates during cell wall construction, rendering
cellulose more amenable to pretreatment and enzyme digestion. Tobacco and maize plants were healthy and developed normally
compared with the wild type (WT). After thermochemical pretreatment and enzyme digestion, transformed plants were clearly
more digestible than WT, requiring lower pretreatment severity to achieve comparable conversion levels. Furthermore, the decreased
recalcitrance was not due to post-pretreatment residual E1 activity and could not be reproduced by the addition of exogenous E1 to the biomass prior to pretreatment, indicating that the expression of E1 during cell wall construction altered the inherent recalcitrance of the cell wall. 相似文献
120.
Eric J Suh Matthew Y Remillard Aster Legesse-Miller Elizabeth L Johnson Johanna MS Lemons Talia R Chapman Joshua J Forman Mina Kojima Eric S Silberman Hilary A Coller 《Genome biology》2012,13(12):R121