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21.
Processes underlying aesthetic appreciation of formal graphic black and white patterns were investigated. In previous EEG studies on aesthetic and symmetry judgments, an early frontocentral negativity has been observed for not beautiful judgments, and interpreted as reflecting an impression formation. In addition, a lateralized late positivity, more pronounced in the aesthetic than in the symmetry judgment task, has been interpreted as reflecting evaluative categorization; and a sustained posterior negativity for not symmetric judgments, has been interpreted as reflecting a prolonged symmetry analysis. Here, we investigated whether these processes occur spontaneously, i.e. independent of an aesthetics task instruction or a judgment task demand. Participants were randomly assigned to two group conditions. In the Viewing condition, participants were instructed to view graphic patterns, and to detect a probe. In the Contemplation condition, participants were instructed to contemplate the beauty of the patterns, and to detect a probe. No aesthetics-related response was required in either condition. ERP results suggest that symmetry analysis occurred spontaneously. Evaluative categorization, reflected by a late positivity, required an aesthetics instruction and did not occur spontaneously. This process was elicited without an overt aesthetic judgment. An early frontocentral negativity for not beautiful patterns, interpreted as reflecting impression formation, did not occur (in contrast to previous studies that required an overt aesthetic judgment). Given the present data, aesthetic appreciation of graphic patterns requires different sub-processes. Aesthetic contemplation is reflected by a lateralized late positivity, whilst an aesthetic judgment is additionally reflected by an early frontocentral negativity. Aesthetic appreciation of beauty appears to require intention and is not spontaneous in character. 相似文献
22.
L. J. Jennings G. M. Salido M. -J. Pozo J. S. Davison K. A. Sharkey R. W. Lea J. Singh 《Inflammation research》1995,44(10):447-453
We have investigated the effects of histamine on motility of the gallbladder and characterized the receptor types involved. Histamine and the histamine H1-receptor agonist, 2-thiazolylethylamine (2-TEA) contracted the isolated guinea-pig gallbladder strip in a dose dependent manner. The contractile response to histamine was shifted to the right by the H1-receptor antagonist, mepyramine. In pre-contracted gallbladder strips, the H2-receptor agonist dimaprit reduced the tension generated in a dose dependent fashion. The histamine H2-receptor antagonist, ranitidine shifted the histamine concentration effect curve to the left and attenuated the dose dependent relaxations elicited at high concentrations. The histamine H3-receptor agonist, (R)--methylhistamine (RMHA) elicited dose dependent contraction of the tissue which was significantly inhibited in the presence of mepyramine. The effects of electrical field stimulation (EFS) on the strips were not significantly altered by the presence of RMHA (10–10–10–7 M) indicating little pre-synaptic H3 activity in this tissue. Histamine immunoreactivity (IR) was detected in gallbladder whole mount preparations of the mucosa and the muscularis/serosa. The histamine IR appeared cell bound in cells of varying morphological characteristics but no IR was detected in nerve fibres or cell bodies (ganglia). Alcian blue staining was consistent with the distribution of histamine IR cells as mast cells. The results indicate that histamine is distributed in the guinea-pig gallbladder and it can regulate contractile activity via activation of H1 and H2 but not H3 receptors. 相似文献
23.
24.
Chavez-Rueda K Agundis-Mata C Zenteno E Shibayama M Tsutsumi V Muñoz O Leaños-Miranda A Blanco-Favela F 《Journal of immunological methods》2002,262(1-2):29-40
The protozoan parasite Entamoeba histolytica is the etiological agent of human amebiasis. The pathology of the disease starts with the cytolysis of the host target cells by amoebae. It is initiated by the adhesion of trophozoites to the host cells, through surface lectin via specific receptors. These adherence lectins have been demonstrated to be highly conserved, and can be recognised by serum antibodies from patients with invasive amebiasis.Some of these molecules have been used as antigens in serologic studies, which has been very helpful in the diagnosis of invasive intestinal amebiasis. However, false-positive serologic reactivity can occur using E. histolytica extracts and purified antigens. Additional problems are because the extracts display a great enzymatic activity. Several diagnostic methods, using different molecules and techniques, have been described. However, the problem still remains since these tests are not capable of differentiating between amoebic liver abscess (ALA) and intestinal amebiasis.Here, the research has been addressed to the 66-kDa antigen, which is a part of the outer membrane proteins from the E. histolytica strain HM1-IMSS trophozoites. First of all, we characterized the 66-kDa antigen in order to prove the relevance. We found that the 66-kDa antigen is a part of the plasma membranes and is distributed rather homogeneously on the cell surface of trophozoites. Apparently, the 66-kDa antigen is a glycoprotein. Using a monoclonal antibody (MAb), we found 25% of inhibition in the erythrophagocytosis by the trophozoites.Starting form one monoclonal antibody, we prepared an anti-idiotype (anti-Id) antibody reagent, with the purpose of searching for the different expressions of the idiotype between the sera from ALA and the intestinal amebiasis patients. Moreover, we produced the antibody Ab3 that is capable of recognising the 66-kDa antigen; it means that the Ab2 displays the internal image of the antigen. We found that 91.6% of the serum from ALA patients displayed the expression of the Id. In contrast, 15.7% of the E. histolytica asymtomatic cyst carriers displayed the Id expression, 6.6% of the patients with another parasite infection, and 11% of the negative controls (serum from umbilical cords of newborn babies). Our results showed that the expression of the Id could be differentiated among the AHA patients from the other groups with a 91.6% sensibility and 88.3% specificity. 相似文献
25.
David C. Mohr Lea Vella Stacey Hart Timothy Heckman Gregory Simon 《Clinical psychology》2008,15(3):243-253
Increasingly, the telephone is being used to deliver psychotherapy for depression, in part as a means to reduce barriers to treatment. Twelve trials of telephone-administered psychotherapies, in which depressive symptoms were assessed, were included. There was a significant reduction in depressive symptoms for patients enrolled in telephone-administered psychotherapy as compared to control conditions ( d = 0.26, 95% confidence interval [CI] = 0.14–0.39, p < .0001). There was also a significant reduction in depressive symptoms in analyses of pretreatment to posttreatment change ( d = 0.81, 95% CI = 0.50–1.13, p < .0001). The mean attrition rate was 7.56% (95% CI = 4.23–10.90). These findings suggest that telephone-administered psychotherapy can produce significant reductions in depressive symptoms. Attrition rates were considerably lower than rates reported in face-to-face psychotherapy. 相似文献
26.
Francesca Fernandez Teresa Esposito Rod A Lea Natalie J Colson Alfredo Ciccodicola Fernando Gianfrancesco Lyn R Griffiths 《BMC medical genetics》2008,9(1):109
Background
Migraine is a neurological disorder characterized by recurrent attacks of severe headache, affecting around 12% of Caucasian populations. It is well known that migraine has a strong genetic component, although the number and type of genes involved is still unclear. Prior linkage studies have reported mapping of a migraine gene to chromosome Xq 24–28, a region containing a cluster of genes for GABA A receptors (GABRE, GABRA3, GABRQ), which are potential candidate genes for migraine. The GABA neurotransmitter has been implicated in migraine pathophysiology previously; however its exact role has not yet been established, although GABA receptors agonists have been the target of therapeutic developments. The aim of the present research is to investigate the role of the potential candidate genes reported on chromosome Xq 24–28 region in migraine susceptibility. In this study, we have focused on the subunit GABA A receptors type ε (GABRE) and type θ (GABRQ) genes and their involvement in migraine. 相似文献27.
Hinckley CA Hartley R Wu L Todd A Ziskind-Conhaim L 《Journal of neurophysiology》2005,93(3):1439-1449
Electrophysiological and morphological properties of genetically identified spinal interneurons were examined to elucidate their possible contribution to locomotor-like rhythmic activity in 1- to 4-day-old mice. In the transgenic mice used in our study, the HB9 promotor controlled the expression of the reporter gene enhanced green fluorescent protein (eGFP), giving rise to GFP+ motoneurons and ventral interneurons. However, only motoneurons and a small group of bipolar, GFP+ interneurons expressed the HB9 protein. The HB9(+)/GFP+ interneurons were clustered close to the medial surface in lamina VIII along segments L1-L3. The correlation between activity pattern in these visually identified interneurons and motoneuron output was examined using simultaneous whole cell and ventral root recordings. Neurochemically induced rhythmic membrane depolarizations in HB9/GFP interneurons were synchronous with ventral root rhythms, indicating that the interneurons received synaptic inputs from rhythm-generating networks. The frequency of excitatory postsynaptic currents significantly increased during ventral root bursts, but there was no change in the frequency of inhibitory postsynaptic currents during the cycle period. These data implied that HB9/GFP interneurons received primarily excitatory inputs from rhythmogenic interneurons. Neurobiotin-filled axon terminals were in close apposition to other neurons in the cluster and to motoneuron dendrites, raising the possibility that HB9/GFP interneurons formed synaptic connections with each other and with motoneurons. The expression of the vesicular glutamate transporter 2 in axon terminals of HB9/GFP interneurons indicated that these were glutamatergic interneurons. Our findings suggest that the visually identified HB9/GFP interneurons are premotor excitatory interneurons and putative constituents of networks generating locomotor rhythms in the mammalian spinal cord. 相似文献
28.
Eating behaviors are influenced by the reinforcing properties of foods that can favor decisions driven by reward incentives over metabolic needs. These food reward-motivated behaviors are modulated by gut-derived peptides such as ghrelin and glucagon-like peptide-1 (GLP-1) that are well-established to promote or reduce energy intake, respectively. In this review we highlight the antagonizing actions of ghrelin and GLP-1 on various behavioral constructs related to food reward/reinforcement, including reactivity to food cues, conditioned meal anticipation, effort-based food-motivated behaviors, and flavor-nutrient preference and aversion learning. We integrate physiological and behavioral neuroscience studies conducted in both rodents and human to illustrate translational findings of interest for the treatment of obesity or metabolic impairments. Collectively, the literature discussed herein highlights a model where ghrelin and GLP-1 regulate food reward-motivated behaviors via both competing and independent neurobiological and behavioral mechanisms. 相似文献
29.
Michael P. Cary Farica Zhuang Rachel Lea Draelos Wei Pan Sathya Amarasekara Brian J. Douthit Yunah Kang Cathleen S. Colón-Emeric 《Journal of the American Medical Directors Association》2021,22(2):291-296
ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively. 相似文献