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排序方式: 共有410条查询结果,搜索用时 15 毫秒
151.
152.
Anthony W. S. Chan Jie Jiang Yiju Chen Chunxia Li Melinda S. Prucha Yijuan Hu Tim Chi Sean Moran Tayeb Rahim Shihua Li Xiaojiang Li Stuart M. Zola Claudia M. Testa Hui Mao Rosa Villalba Yoland Smith Xiaodong Zhang Jocelyne Bachevalier 《PloS one》2015,10(5)
One of the roadblocks to developing effective therapeutics for Huntington disease (HD) is the lack of animal models that develop progressive clinical traits comparable to those seen in patients. Here we report a longitudinal study that encompasses cognitive and motor assessment, and neuroimaging of a group of transgenic HD and control monkeys from infancy to adulthood. Along with progressive cognitive and motor impairment, neuroimaging revealed a progressive reduction in striatal volume. Magnetic resonance spectroscopy at 48 months of age revealed a decrease of N-acetylaspartate (NAA), further suggesting neuronal damage/loss in the striatum. Postmortem neuropathological analyses revealed significant neuronal loss in the striatum. Our results indicate that HD monkeys share similar disease patterns with HD patients, making them potentially suitable as a preclinical HD animal model. 相似文献
153.
Rahim Alhamzawi 《Statistics in biosciences》2016,8(2):358-373
This paper introduces a Bayesian approach for composite quantile regression employing the skewed Laplace distribution for the error distribution. We use a two-level hierarchical Bayesian model for coefficient estimation and future selection which assumes a prior distribution that favors sparseness. An efficient Gibbs sampling algorithm is developed to update the unknown quantities from the posteriors. The proposed approach is illustrated via simulation studies and two real datasets. Results indicate that the proposed approach performs quite good in comparison to the other approaches. 相似文献
154.
155.
Heavy metal biosorption by biomass of Ochrobactrum anthropi producing exopolysaccharide in activated sludge 总被引:5,自引:0,他引:5
The removal of chromium, cadmium and copper, toxic metals of high environmental priority due to their toxicity, from dilute aqueous solutions has been studied in the present work, applying a dead exopolysaccharide producing bacterium, Ochrobactrum anthropi, isolated from activated sludge. Particularly, the effect of pH, metal concentration and the effects of contact time were considered. Optimum adsorption pH values of chromium(VI), cadmium(II) and copper(II) were 2.0, 8.0 and 3.0 respectively. Experimental results also showed the influence of initial metal concentration on the metal uptake for dried biomass. Both the Freundlich and Langmuir adsorption models were suitable for describing the short-term biosorption of chromium(VI), cadmium(II) and copper(II) by O. anthropi. 相似文献
156.
157.
Z Rahim S C Sanyal K M Aziz M I Huq A A Chowdhury 《Applied and environmental microbiology》1984,48(4):865-867
Strains of Aeromonas hydrophila isolated from skin infections of common freshwater fish in Bangladesh were tested for enterotoxin production, hemolysin production, and any correlation between these two activities. We also tested the resistance patterns of A. hydrophila to different drugs, especially in relation to ampicillin. The A. hydrophila strains produced an enterotoxin that was related to their beta-hemolytic activities. Production of beta-hemolysin may thus be an indicator of enterotoxicity. As 50% of the strains of A. hydrophila were found to be susceptible to 12.5 micrograms of ampicillin per ml, media containing this antibiotic may not be suitable for their isolation. 相似文献
158.
Abdur Rahman Khan Muhammad Riaz Aref A. Bin Abdulhak Mohamad A. Al-Tannir Musa A. Garbati Patricia J. Erwin Larry M. Baddour Imad M. Tleyjeh 《PloS one》2013,8(1)
Background
Emerging epidemiological evidence suggests that statins may reduce the risk of community-acquired pneumonia (CAP) and its complications.Purpose
Performed a systematic review to address the role of statins in the prevention or treatment of CAP.Data Source
Ovid MEDLINE, Cochrane, EMBASE, ISI Web of Science, and Scopus from inception through December 2011 were searched for randomized clinical trials, cohort and case-control studies.Study Selection
Two authors independently reviewed studies that examined the role of statins in CAP.Data Extraction
Data about study characteristics, adjusted effect-estimates and quality characteristics was extracted.Data Synthesis
Eighteen studies corresponding to 21 effect-estimates (eight and 13 of which addressed the preventive and therapeutic roles of statins, respectively) were included. All studies were of good methodological quality. Random-effects meta-analyses of adjusted effect-estimates were used. Statins were associated with a lower risk of CAP, 0.84 (95% CI, 0.74–0.95), I2 = 90.5% and a lower short-term mortality in patients with CAP, 0.68 (95% CI, 0.59–0.78), I2 = 75.7%. Meta-regression did not identify sources of heterogeneity. A funnel plot suggested publication bias in the treatment group, which was adjusted by a novel regression method with a resultant effect-estimate of 0.85 (95% CI, 0.77–0.93). Sensitivity analyses using the rule-out approach showed that it is unlikely that the results were due to an unmeasured confounder.Conclusions
Our meta-analysis reveals a beneficial role of statins for the risk of development and mortality associated with CAP. However, the results constitute very low quality evidence as per the GRADE framework due to observational study design, heterogeneity and publication bias. 相似文献159.
Haruan (Channa striatus) is in great demand in the Malaysian domestic fish market. In the present study, mtDNA cyt b was used to investigate genetic variation of C. striatus among populations in Peninsular Malaysia. The overall population of C. striatus demonstrated a high level of haplotype diversity (h) and a low-to-moderate level of nucleotide diversity (π). Analysis of molecular variance (AMOVA) results showed a significantly different genetic differentiation among 6 populations (FST = 0.37566, P = 0.01). Gene flow (Nm) was high and ranged from 0.32469 to infinity (∞). No significant relationship between genetic distance and geographic distance was detected. A UPGMA tree based on the distance matrix of net interpopulation nucleotide divergence (dA) and haplotype network of mtDNA cyt b revealed that C. striatus is divided into 2 major clades. The neutrality and mismatch distribution tests for all populations suggested that C. striatus in the study areas had undergone population expansion. The estimated time of population expansion in the mtDNA cyt b of C. striatus populations occurred 0.72-6.19 million years ago. Genetic diversity of mtDNA cyt b and population structure among Haruan populations in Peninsular Malaysia will be useful in fisheries management for standardization for Good Agriculture Practices (GAP) in fish-farming technology, as well as providing the basis for Good Manufacturing Practices (GMP). 相似文献
160.