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Szucs Regina P.; Frankel Paul S.; McMahon Lance R; Cunningham Kathryn A. 《Canadian Metallurgical Quarterly》2005,119(5):1173
Serotonin 5-HT2A receptor antagonists have been shown to attenuate the locomotor stimulant effects of cocaine in rats. The present study used the expression of c-Fos protein as a marker to identify brain areas through which 5-HT2A receptors may modulate cocaine-induced behaviors. Significant correlations were observed between cocaine-induced hyperactivity and c-Fos expression in the nucleus accumbens core (NAcC), caudate-putamen (CPu), and subthalamic nucleus. In a separate experiment, a low, behaviorally relevant dose of cocaine was found to increase c-Fos immunoreactivity in the medial CPu, NAcC, and nucleus accumbens shell (NAcSh). The selective 5-HT2A receptor antagonist M100907 significantly attenuated cocaine-induced c-Fos expression in the medial CPu and in the NAcSh. These data suggest that 5-HT2A receptors in the NAcSh and CPu or in afferents to these regions may contribute to genomic responses to cocaine in the brain as well as to cocaine-induced locomotor activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
The distinction between underlying and superficial linguistic structure is a staple of modern cognitive psychology. Despite increasingly diverse conceptions of syntactic relations in linguistic theory, the received view in psycholinguistics has remained one in which the entities assigned to underlying relations may assume different surface relations. This view is examined in the context of language production and evidence is reviewed that the disposition to bind animate entities to the surface subject relation is a basic feature of language use, suggesting that mappings from conceptual categories to syntactic relations form a main support of the bridge from conception to language. Proceeding on this assumption, an evaluation of competing accounts of the mapping process in production is given. Results argue against syntactic relation-changing operations, but favor a division between meaning- and form-related mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
This study compared the effects of estrogen (E) on the hyperactivity induced by (+)-3,4-methylenedioxymethamphetamine (MDMA) with E effects on cocaine-evoked hyperactivity in female rats. Sprague-Dawley rats were ovariectomized (OVX); half of them received a 17β-estradiol (E?) implant (OVX + E). Three weeks later, rats received saline, (+)-MDMA (1, 2, or 4 mg/kg) or cocaine (5, 10, or 20 mg/kg), and locomotor activity was monitored. OVX + E rats exhibited greater locomotor hyperactivity in response to both psychostimulants than did OVX rats. The enhanced response to cocaine appeared within 5 min following drug injection whereas the enhanced response to (+)-MDMA was delayed for approximately 30 min. The differential effects of E on hyperactivity may be due to the unique profiles of dopamine (DA) and serotonin (5-HT) in response to (+)-MDMA and cocaine. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
It was hypothesized that exposure to complementary representations of the poor as happier and more honest than the rich would lead to increased support for the status quo. In Study 1, exposure to "poor but happy" and "rich but miserable" stereotype exemplars led people to score higher on a general measure of system justification, compared with people who were exposed to noncomplementary exemplars. Study 2 replicated this effect with "poor but honest" and "rich but dishonest" complementary stereotypes. In Studies 3 and 4, exposure to noncomplementary stereotype exemplars implicitly activated justice concerns, as indicated by faster reaction times to justice-related than neutral words in a lexical decision task. Evidence also suggested that the Protestant work ethic may moderate the effects of stereotype exposure on explicit system justification (but not implicit activation). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Taylor H. Gerry; Dietrich Ann; Nuss Kathryn; Wright Martha; Rusin Jerome; Bangert Barbara; Minich Nori; Yeates Keith Owen 《Canadian Metallurgical Quarterly》2010,24(2):148
To investigate postconcussive symptoms (PCS) following pediatric mild traumatic brain injury (mTBI), 8- to 15-year-old children with mTBI (n = 186) and a comparison group with uncomplicated orthopedic injuries (OI, n = 99) were recruited from two emergency departments. Parent and child ratings of PCS and symptom counts were obtained within 3 weeks after injury (baseline) and at 1, 3, and 12 months postinjury. The mTBI group also completed magnetic resonance imaging at baseline. Group differences were examined using growth modeling, controlling for age at injury, sex, socioeconomic status, and (for parent-based measures) preinjury symptom levels. Relative to the OI group, the mTBI group had higher ratings of somatic PCS and parent counts of PCS at the initial assessments, but higher parent ratings of cognitive PCS and child counts of PCS throughout follow-up. Higher levels of PCS in the mTBI group were associated with motor-vehicle-related trauma, loss of consciousness, neuroimaging abnormalities, and hospitalization. The findings validate both transient and persistent PCS in children with mTBI and document associations of symptoms with injury and noninjury factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Gabriele Mocciaro Simona DAmore Benjamin Jenkins Richard Kay Antonio Murgia Luis Vicente Herrera-Marcos Stefanie Neun Alice P. Sowton Zoe Hall Susana Alejandra Palma-Duran Giuseppe Palasciano Frank Reimann Andrew Murray Patrizia Suppressa Carlo Sabb Antonio Moschetta Albert Koulman Julian L. Griffin Michele Vacca 《International journal of molecular sciences》2022,23(12)
The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors characterised by central obesity, atherogenic dyslipidaemia, and changes in the circulating lipidome; the underlying mechanisms that lead to this lipid remodelling have only been partially elucidated. This study used an integrated “omics” approach (untargeted whole serum lipidomics, targeted proteomics, and lipoprotein lipidomics) to study lipoprotein remodelling and HDL composition in subjects with central obesity diagnosed with MetS (vs. controls). Compared with healthy subjects, MetS patients showed higher free fatty acids, diglycerides, phosphatidylcholines, and triglycerides, particularly those enriched in products of de novo lipogenesis. On the other hand, the “lysophosphatidylcholines to phosphatidylcholines” and “cholesteryl ester to free cholesterol” ratios were reduced, pointing to a lower activity of lecithin cholesterol acyltransferase (LCAT) in MetS; LCAT activity (directly measured and predicted by lipidomic ratios) was positively correlated with high-density lipoprotein cholesterol (HDL-C) and negatively correlated with body mass index (BMI) and insulin resistance. Moreover, many phosphatidylcholines and sphingomyelins were significantly lower in the HDL of MetS patients and strongly correlated with BMI and clinical metabolic parameters. These results suggest that MetS is associated with an impairment of phospholipid metabolism in HDL, partially led by LCAT, and associated with obesity and underlying insulin resistance. This study proposes a candidate strategy to use integrated “omics” approaches to gain mechanistic insights into lipoprotein remodelling, thus deepening the knowledge regarding the molecular basis of the association between MetS and atherosclerosis. 相似文献
69.
Kay MK Cartwright EJ Maceachern D McCullough J Barzilay E Mintz E Duchin JS Macdonald K Turnsek M Tarr C Talkington D Newton A Marfin AA 《Journal of food protection》2012,75(4):762-764
We report a cluster of severe diarrheal disease caused by Vibrio mimicus infection among four persons who had consumed leftover crayfish the day after a private crayfish boil. Gastrointestinal illness caused by Vibrio mimicus has not been reported previously in Washington State. Three cases were laboratory confirmed by stool culture; using PCR, isolates were found to have ctx genes that encode cholera toxin (CT). Two of the cases were hospitalized under intensive care with a cholera-like illness. The illnesses were most likely caused by cross-contamination of cooked crayfish with uncooked crayfish; however, V. mimicus was not isolated nor were CT genes detected by PCR in leftover samples of frozen crayfish. Clinicians should be aware that V. mimicus can produce CT and that V. mimicus infection can cause severe illness. 相似文献
70.
ABSTRACTWith the capability of additive manufacturing, complex structures are easily fabricated to achieve various design purposes. In this work, a bi-material strip temperature sensor with complex periodic pattern design is purposed and investigated through both the analytical modeling and multi-physics finite element analysis. Three design patterns are considered: standard, E-shape and S-shape. In the standard solid strip design, the curvature of the bi-material strip under temperature variation is in a linear relationship with the coefficient of thermal expansion (CTE) difference, but in a reciprocal relationship with the strip thickness. The curvature of the bi-material strip depends on the Young’s modulus ratio and layer thickness ratio of the two materials, but is independent of the magnitude of the materials’ Young’s modulus. Based on analytical derivation and numerical validation, the optimized design parameters can be provided. Compared to S-shape pattern design, E-shape pattern design can significantly increase the temperature sensitivity of the bi-material strip. An analytical prediction of the E-shape pattern’s temperature sensitivity is introduced and discussed. This work proves the concept that new design space becomes available with the capability of additive manufacturing, and provides the general design guideline for a bi-material strip based temperature sensor with possible design patterns. 相似文献