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排序方式: 共有1162条查询结果,搜索用时 15 毫秒
31.
Thomas R. Jackson Kristine Salmina Anda Huna Inna Inashkina Eriks Jankevics Una Riekstina Zane Kalnina Andrey Ivanov Paul A. Townsend Mark S. Cragg Jekaterina Erenpreisa 《Cell cycle (Georgetown, Tex.)》2013,12(3):430-431
Comment on: Wu R, et al. Clin Cancer Res 2011; 17:7359–72 相似文献
32.
Objective
Studies have shown that children with ADHD profit from working memory training, although few studies have investigated transfer effects comprehensively. The current Randomized Controlled Trial analyzes transfer to other neuropsychological (NP) domains, academic performance and everyday functioning at home and school.Method
Sixty-seven children with ADHD were randomized into a control group or a training group. The training group underwent Cogmed’s RoboMemo program. All participants were assessed pre-training, immediately after and eight months later with a battery of NP tests, measures of mathematical and reading skills, as well as rating scales filled out by parents and teachers.Results
There was a significant training effect in psychomotor speed, but not to any other NP measures. Reading and mathematics were improved. There were no training induced changes in symptom rating scales either at home or at school. The increased reading scores remained significant eight months later.Conclusion
The study is the most comprehensive study of transfer effects to date, and with mixed results compared to previous research. More research is needed regarding how to improve the training program and the conditions and thresholds for successful training.Trial Registration
Controlled-Trials.com ISRCTN19133620 相似文献33.
Objective
The aim of the study is to evaluate the long-term near-transfer effects of computerized working memory (WM) training on standard WM tasks in children with Attention-Deficit/Hyperactivity Disorder (ADHD).Method
Sixty-seven children aged 10–12 years in Vestfold/Telemark counties (Norway) diagnosed with F90.0 Hyperkinetic disorder (ICD-10) were randomly assigned to training or control group. The training group participated in a 25-day training program at school, while the control group received treatment-as-usual. Participants were tested one week before intervention, immediately after and eight months later. Based on a component analysis, six measures of WM were grouped into composites representing Visual, Auditory and Manipulation WM.Results
The training group had significant long-term differential gains compared to the control group on all outcome measures. Performance gains for the training group were significantly higher in the visual domain than in the auditory domain. The differential gain in Manipulation WM persisted after controlling for an increase in simple storage capacity.Conclusion
Systematic training resulted in a long-term positive gain in performance on similar tasks, indicating the viability of training interventions for children with ADHD. The results provide evidence for both domain-general and domain-specific models. Far-transfer effects were not investigated in this article.Trial Registration: Controlled-Trials.com ISRCTN19133620 相似文献34.
Joani M. Christensen Gabriel A. Brat Kristine E. Johnson Yongping Chen Kate J. Buretta Damon S. Cooney Gerald Brandacher W. P. Andrew Lee Xingde Li Justin M. Sacks 《PloS one》2013,8(11)
Distinguishing cutaneous infection from sterile inflammation is a diagnostic challenge and currently relies upon subjective interpretation of clinical parameters, microbiological data, and nonspecific imaging. Assessing characteristic variations in leukocytic infiltration may provide more specific information. In this study, we demonstrate that homing of systemically administered monocytes tagged using indocyanine green (ICG), an FDA-approved near infrared dye, may be assessed non-invasively using clinically-applicable laser angiography systems to investigate cutaneous inflammatory processes. RAW 264.7 mouse monocytes co-incubated with ICG fluoresce brightly in the near infrared range. In vitro, the loaded cells retained the ability to chemotax toward monocyte chemotactic protein-1. Following intravascular injection of loaded cells into BALB/c mice with induced sterile inflammation (Complete Freund’s Adjuvant inoculation) or infection (Group A Streptococcus inoculation) of the hind limb, non-invasive whole animal imaging revealed local fluorescence at the inoculation site. There was significantly higher fluorescence of the inoculation site in the infection model than in the inflammation model as early as 2 hours after injection (p<0.05). Microscopic examination of bacterial inoculation site tissue revealed points of near infrared fluorescence, suggesting the presence of ICG-loaded cells. Development of a non-invasive technique to rapidly image inflammatory states without radiation may lead to new tools to distinguish infectious conditions from sterile inflammatory conditions at the bedside. 相似文献
35.
36.
Huaiwei Liu Yuanzhang Sun Kristine Rose M. Ramos Grace M. Nisola Kris Ni?o G. Valdehuesa Won–Keun Lee Si Jae Park Wook-Jin Chung 《PloS one》2013,8(12)
Embden-Meyerhof pathway (EMP) in tandem with 2-C-methyl-D-erythritol 4-phosphate pathway (MEP) is commonly used for isoprenoid biosynthesis in E. coli. However, this combination has limitations as EMP generates an imbalanced distribution of pyruvate and glyceraldehyde-3-phosphate (G3P). Herein, four glycolytic pathways—EMP, Entner-Doudoroff Pathway (EDP), Pentose Phosphate Pathway (PPP) and Dahms pathway were tested as MEP feeding modules for isoprene production. Results revealed the highest isoprene production from EDP containing modules, wherein pyruvate and G3P were generated simultaneously; isoprene titer and yield were more than three and six times higher than those of the EMP module, respectively. Additionally, the PPP module that generates G3P prior to pyruvate was significantly more effective than the Dahms pathway, in which pyruvate production precedes G3P. In terms of precursor generation and energy/reducing-equivalent supply, EDP+PPP was found to be the ideal feeding module for MEP. These findings may launch a new direction for the optimization of MEP-dependent isoprenoid biosynthesis pathways. 相似文献
37.
William J. Zielinski Fredrick V. Schlexer Sean A. Parks Kristine L. Pilgrim Michael K. Schwartz 《Conservation Genetics》2013,14(2):369-383
The landscape genetics framework is typically applied to broad regions that occupy only small portions of a species’ range. Rarely is the entire range of a taxon the subject of study. We examined the landscape genetic structure of the endangered Point Arena mountain beaver (Aplodontia rufa nigra), whose isolated geographic range is found in a restricted (85 km2) but heterogenous region in California. Based on its diminutive range we may predict widespread gene flow and a relatively weak role for landscape variation in defining genetic structure. We used skin, bone, tissue and noninvasively collected hair samples to describe genetic substructure and model gene flow. We examined spatial partitioning of multilocus DNA genotypes and mitochondrial DNA haplotypes. We identified 3 groups from microsatellite data, all of which had low estimates of effective population size consistent with significant tests for historical bottlenecks. We used least-cost-path analysis with the microsatellites to examine how vegetation type affects gene flow in a landscape genetics framework. Gene flow was best predicted by a model with “Forest” as the most permeable, followed by “Riparian”. Agricultural lands demonstrated the highest resistance. MtDNA data revealed only two haplotypes: one was represented in all 57 individuals that occurred north of the east–west flowing Garcia River. South of the river, however, both haplotypes occurred, often at the same site suggesting that the river may have affected historical patterns of genetic divergence. 相似文献
38.
Leigh Perreault Carrie McCurdy Anna A. Kerege Julie Houck Kristine F?rch Bryan C. Bergman 《PloS one》2013,8(7)
Aims/Hypothesis
Glucose sensing (eg. glucokinase activity) becomes impaired in the development of type 2 diabetes, the etiology of which is unclear. Estrogen can stimulate glucokinase activity, whereas the pervasive environmental pollutant bisphenol A (BPA) can inhibit estrogen action, hence we aimed to determine the effect of BPA on glucokinase activity directly.Methods
To evaluate a potential acute effect on hepatic glucokinase activity, BPA in water (n = 5) vs. water alone (n = 5) was administered at the EPA’s purported “safe dose” (50 µg/kg) by gavage to lean 6-month old male C57BL/6 mice. Two hours later, animals were euthanized and hepatic glucokinase activity measured over glucose levels from 1–20 mmol/l in liver homogenate. To determine the effect of chronic BPA exposure on hepatic glucokinase activity, lean 6-month old male C57BL/6 mice were provided with water (n = 15) or water with 1.75 mM BPA (∼50 µg/kg/day; n = 14) for 2 weeks. Following the 2-week exposure, animals were euthanized and glucokinase activity measured as above.Results
Hepatic glucokinase activity was signficantly suppressed after 2 hours in animals given an oral BPA bolus compared to those who received only water (p = 0.002–0.029 at glucose 5–20 mmol/l; overall treatment effect p<0.001). Exposure to BPA over 2 weeks also suppressed hepatic glucokinase activity in exposed vs. unexposed mice (overall treatment effect, p = 0.003). In both experiments, the Hill coefficient was higher and Vmax lower in mice treated with BPA.Conclusions/Interpretation
Both acute and chronic exposure to BPA significantly impair hepatic glucokinase activity and function. These findings identify a potential mechanism for how BPA may increase risk for diabetes. 相似文献39.
40.
Ling Zhao L. Dillon Birdwell Ashley Wu Ruth Elliott Kristine M. Rose Judith M. Phillips Yize Li Judith Grinspan Robert H. Silverman Susan R. Weiss 《Journal of virology》2013,87(15):8408-8418
Previous studies have demonstrated that the murine coronavirus mouse hepatitis virus (MHV) nonstructural protein 2 (ns2) is a 2′,5′-phosphodiesterase that inhibits activation of the interferon-induced oligoadenylate synthetase (OAS)-RNase L pathway. Enzymatically active ns2 is required for efficient MHV replication in macrophages, as well as for the induction of hepatitis in C57BL/6 mice. In contrast, following intranasal or intracranial inoculation, efficient replication of MHV in the brain is not dependent on an enzymatically active ns2. The replication of wild-type MHV strain A59 (A59) and a mutant with an inactive phosphodiesterase (ns2-H126R) was assessed in primary hepatocytes and primary central nervous system (CNS) cell types—neurons, astrocytes, and oligodendrocytes. A59 and ns2-H126R replicated with similar kinetics in all cell types tested, except macrophages and microglia. RNase L activity, as assessed by rRNA cleavage, was induced by ns2-H126R, but not by A59, and only in macrophages and microglia. Activation of RNase L correlated with the induction of type I interferon and the consequent high levels of OAS mRNA induced in these cell types. Pretreatment of nonmyeloid cells with interferon restricted A59 and ns2-H126R to the same extent and failed to activate RNase L following infection, despite induction of OAS expression. However, rRNA degradation was induced by treatment of astrocytes or oligodendrocytes with poly(I·C). Thus, RNase L activation during MHV infection is cell type specific and correlates with relatively high levels of expression of OAS genes, which are necessary but not sufficient for induction of an effective RNase L antiviral response. 相似文献