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排序方式: 共有1084条查询结果,搜索用时 15 毫秒
51.
Emily B. Button Andrew S. Mitchell Marcia M. Domingos Jessica H.-J. Chung Ryan M. Bradley Ashkan Hashemi Phillip M. Marvyn Ashley C. Patterson Ken D. Stark Joe Quadrilatero Robin E. Duncan 《Lipids》2014,49(4):305-316
Neuroinflammation is a component of age-related neurodegenerative diseases and cognitive decline. Saturated (SFA) and monounsaturated (MUFA) fatty acids are bioactive molecules that may play different extrinsic and intrinsic roles in neuroinflammation, serving as exogenous ligands for cellular receptors, or endogenous components of cell structural, energetic and signaling pathways. We determined the fatty acyl profile of BV2 microglial cells before and after acute activation with lipopolysaccharide (LPS). We also investigated the effect of SFA and MUFA pretreatment on the production of an invasive, neurotoxic phenotype in BV2 cells. Acute activation of BV2 microglia resulted in an increase in the relative content of SFA (12:0, 16:0, 18:0, 20:0, 22:0, and 24:0 increased significantly), and a relative decrease in the content of MUFA (16:1n7, 18:1n7, 18:1n9, 20:1n9, 24:1n9 decreased significantly). In agreement, the major stearoyl-CoA desaturase (SCD) isoform in BV2 cells, SCD2, was significantly down-regulated by LPS. We next treated cells with SFA (16:0 or 18:0) or MUFA (16:1n7 or 18:1n9), and found that levels of secreted IL6 were increased, as was secreted MMP9-mediated proteolytic activity. To test the functional significance, we treated SH-SY5Y neuronal cells with conditioned medium from BV2 cells pretreated with fatty acids, and found a small but significant induction of cell death. Our findings suggest differential intrinsic roles for SFA and MUFA in activated microglial cells, but similar extrinsic roles for these fatty acid species in inducing activation. Expansion of SFA is important during microglial cell activation, but either supplemental SFA or MUFA may contribute to chronic low-grade neuroinflammation. 相似文献
52.
Impett Emily A.; Gordon Amie M.; Kogan Aleksandr; Oveis Christopher; Gable Shelly L.; Keltner Dacher 《Canadian Metallurgical Quarterly》2010,99(6):948
In 2 daily experience studies and a laboratory study, the authors test predictions from approach-avoidance motivational theory to understand how dating couples can maintain feelings of relationship satisfaction in their daily lives and over the course of time. Approach goals were associated with increased relationship satisfaction on a daily basis and over time, particularly when both partners were high in approach goals. Avoidance goals were associated with decreases in relationship satisfaction over time, and people were particularly dissatisfied when they were involved with a partner with high avoidance goals. People high in approach goals and their partners were rated as relatively more satisfied and responsive to a partner's needs by outside observers in the lab, whereas people with high avoidance goals and their partners were rated as less satisfied and responsive. Positive emotions mediated the link between approach goals and daily satisfaction in both studies, and responsiveness to the partner's needs was an additional behavioral mechanism in Study 2. Implications of these findings for approach-avoidance motivational theory and for the maintenance of satisfying relationships over time are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The authors investigated whether infants are sensitive to visual event trajectory forms, and whether they are sensitive to the underlying dynamics of trajectory forms. The authors habituated 8-month-old infants to a videotaped event run either forward or reversed in time and then switched them to the same event run in the opposite direction. Infants dishabituated when switched to the event with the novel direction in time, indicating sensitivity to the form of the trajectory. Infants exhibited equivalent habituation rates and looking times for forward and reversed events, thus failing to provide evidence that infants are sensitive to the underlying dynamics. In a partial replication of this first experiment, the same pattern of results was found. Both experiments revealed infant sensitivity to the trajectory forms, but not the underlying dynamics of events. The authors discuss implications for methods used in infant event perception studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Emily?S.?PattersonEmail author Michelle?L.?Rogers Marta?L.?Render 《Cognition, Technology & Work》2004,6(3):197-205
There is growing interest in developing video-based methods to evaluate the usefulness and usability of computerised tools in healthcare. In this paper, we propose a human-computer interaction evaluation method that protects the confidentiality of patient information and reduces litigation risks for participants by embedding and analysing performance on probes in complex scenarios with high face validity in a simulated setting. We describe the application of the method to a series of three studies of bar code medication administration (BCMA) software, used to reduce medication errors in the Veterans Administration. 相似文献
57.
Pettinati Helen M.; Evans Frederick J.; Orne Emily C.; Orne Martin T. 《Canadian Metallurgical Quarterly》1981,90(4):345
Evaluated memory for successful and unsuccessful responses to hypnotic suggestions in partially amnesic Ss and in those Ss with normal forgetting. Two analyses (278 undergraduates) demonstrated that highly hypnotizable Ss experiencing partial posthypnotic amnesia tended to show no selective recall for their successes or failures during amnesia, whereas the remainder of the Ss showed definite selective recall of hypnotic success posthypnotically. These findings support F. J. Evans and J. F. Kihlstrom's (see record 1974-06307-001) hypothesis that posthypnotic amnesia involves a disruption of memory organization and suggest that the phenomenon may be mediated by a restriction in the use of normally employed retrieval cues. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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An affinity probe capillary electrophoresis (APCE) assay for guanine-nucleotide-binding proteins (G proteins) was developed using BODIPY FL GTPgammaS (BGTPgammaS), a fluorescently labeled GTP analogue, as the affinity probe. In the assay, BGTPgammaS was incubated with samples containing G proteins and the resulting mixtures of BGTPgammaS-G protein complexes and free BGTPgammaS were separated by capillary electrophoresis and detected with laser-induced fluorescence detection. Separations were completed in less than 30 s using 25 mM Tris, 192 mM glycine at pH 8.5 as the electrophoresis buffer and applying 555 V/cm over a 4-cm separation distance. BGTPgammaS-Galpha(o) peak heights increased linearly with Galpha(o) up to approximately 200 nM using a 50 nM BGTPgammaS probe. The detection limit for Galpha(o) was 2 nM, corresponding to a mass detection limit of 3 amol. The high speed of the APCE assays allowed reaction kinetics and the dissociation constant (Kd) to be determined. The on-rate and off-rate of BGTPgammaS to Galpha(o) were 0.0068 +/- 0.0004 and 0.000 23 +/- 0.000 01 s(-1), respectively. The half-life of the BGTPgammaS-Galpha(o) complex was 3060 +/- 240 s and Kd was 8.6 +/- 0.7 nM. The estimates of these parameters are in good agreement with those obtained using established techniques, indicating the suitability of this method for such measurements. Lowering the temperature of the separation improved the detection of the complex, allowing the assay to be performed on a commercial instrument with longer separation times. Additionally, the capability of the technique to detect several G proteins based on their binding to BGTPgammaS was demonstrated with assays for Galpha and Galpha(i1) and for Ras and Rab3A. 相似文献
59.
Simeon Keates Ray Adams Cathy Bodine Sara Czaja Wayne Gordon Peter Gregor Emily Hacker Vicki Hanson John Kemp Mark Laff Clayton Lewis Michael Pieper John Richards David Rose Anthony Savidis Greg Schultz Paul Snayd Shari Trewin Philip Varker 《Universal Access in the Information Society》2007,5(4):329-339
In October 2005, the IBM Human Ability and Accessibility Center and T.J. Watson Research Center hosted a symposium on “cognitive
and learning difficulties and how they affect access to IT systems”. The central premise of the symposium was the recognition
that cognitive and learning difficulties have a profound impact on a person’s ability to interact with information technology
(IT) systems, but that little support is currently being offered by those systems. By bringing together internationally renowned
experts from a variety of different, but complementary, research fields, the symposium aimed to provide a complete overview
of the issues related to this topic. This paper summarises the discussions and findings of the symposium. 相似文献
60.
Research on therapeutic writing indicates that it can offer a range of physical and psychological benefits. There is no consensus, however, concerning how writing achieves these benefits. To address this question, the authors propose a matrix framework with emotional-cognitive change processes (what can be activated) along its horizontal dimension and abstract-concrete structure (how the processes are activated) along its vertical dimension. On the horizontal dimension, writing can encourage clients who are distant from their emotional world to approach or to modulate emotional intensity, and to create meaning and coherence. Along the vertical dimension, these processes can be activated through tasks that vary in structure, including programmed writing, diaries, journaling, autobiography, storytelling, and poetry. Finally, the authors consider constraints on writing that apply to particular client groups. The matrix framework is meant to encourage clinicians to use therapeutic writing and to assist researchers in framing questions to advance our knowledge of writing as a therapeutic practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献