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641.
642.
Lewis and Fischer-344 rats have been proposed as an addiction model because of their differences in addiction behaviour. It has been suggested that drug addiction is related to learning and memory processes and depends on individual genetic background. We have evaluated learning performance using the eight-arm radial maze (RAM) in Lewis and Fischer-344 adult rats undergoing a chronic treatment with cocaine. In order to study whether morphological alterations were involved in the possible changes in learning after chronic cocaine treatment, we counted the spine density in hippocampal CA1 neurons from animals after the RAM protocol. Our results showed that Fischer-344 rats significantly took more time to carry out test acquisition and made a greater number of errors than Lewis animals. Nevertheless, cocaine treatment did not induce changes in learning and memory processes in both strains of rats. These facts indicate that there are genetic differences in spatial learning and memory that are not modified by the chronic treatment with cocaine. Moreover, hippocampal spine density is cocaine-modulated in both strains of rats. In conclusion, cocaine induces similar changes in hippocampal neurons morphology that are not related to genetic differences in spatial learning in the RAM protocol used here.  相似文献   
643.
The present study describes the psychometric properties of the Portuguese version of the Mental Health Inventory-5 for use with young adolescents. A sample of 367 Portuguese students (aged 10-15 years) completed the Portuguese-language versions of Mental Health Inventory-5 (MHI-5; Berwick et al., 1991), Children's Hope Scale (CHS; Snyder et al., 1997), Students' Life Satisfaction Scale (SLSS; Huebner, 1991a), and Global Self-Worth Sub-scale (Harter, 1985). Analysis of readability, reliability (internal consistency and 1-year stability), factor structure, and criterion-related validity suggested that the MHI-5 can be appropriately used in this age group. Implications of the findings are discussed.  相似文献   
644.
The main objective of this work was to evaluate the characteristics of sleep in patients diagnosed with fibromyalgia syndrome. Sleep architecture in 32 patients with fibromyalgia and 20 healthy controls was evaluated. Following the recommendations of the International Federation of Clinical Neurophysiology, polysomnographies were conducted with fibromyalgia patients and the control subjects. The fibromyalgia patients showed alterations in cyclic organization of sleep and an increased number of periodic leg movements associated with cortical arousals. No significant differences were found in respiratory and oximetry variables or in alpha-delta sleep. The results support that fibromyalgia patients present an increase of superficial sleep at the expense of deep sleep and also an increase of periodic leg movements, which could have a pathogenic effect, facilitating the onset of the illness. Lastly, we discuss the results and propose some future lines of research.  相似文献   
645.
The study aims to analyze how health is self-perceived by a sample of caregivers of dependant relatives and how it compares with general Spanish population scores. The study also focuses on the relations between self-perceived health and burden. The sample comprised 1,257 caregivers living in Biscay who completed the protocol including sociodemographic data, measures of health-related quality of life (SF-36) and burden (Zarit Burden Inventory). Results show that the health perception of the caregivers taking part into the study reached lower scores in comparison to general Spanish population and that this perception was lower in mental than in physical health. Correlational data supports previous findings indicating that high levels of burden are associated with a worse perception of mental and physical health and provide information on how to guide interventions to improve family caregivers' quality of life.  相似文献   
646.
Similar to an auditory chimaera (Smith et al, 2002 Nature 416 87-90), a visual chimaera can be defined as a synthetic image which has the fine spatial structure of one natural image and the envelope of another image in each spatial frequency band. Visual chimaeras constructed in this way could be useful to vision scientists interested in the study of interactions between first-order and second-order visual processing. Although it is almost trivial to generate 1-D chimaeras by means of the Hilbert transform and the analytic signal, problems arise in multidimensional signals like images given that the partial directional Hilbert transform and current 2-D demodulation algorithms are anisotropic or orientation-variant procedures. Here, we present a computational procedure to synthesise visual chimaeras by means of the Riesz transform--an isotropic generalisation of the Hilbert transform for multidimensional signals--and the associated monogenic signal--the vector-valued function counterpart of the analytic signal in which the Riesz transform replaces the Hilbert transform. Examples of visual chimaeras are shown for same/different category images.  相似文献   
647.
In this study, we examined the relationship between familism and family environment type as well as the relationship between family environment type and suicide attempts among Latina youth. Latina teen attempters (n = 109) and nonattempters (n = 107) were recruited from the New York City area. Latent class analysis revealed three family environment types: tight-knit, intermediate-knit, and loose-knit. Tight-knit families (high cohesion and low conflict) were significantly less likely to have teens who attempted suicide as compared with intermediate-knit families or loose-knit families. Moreover, familism increased the odds of being in a tight-knit family versus a loose-knit family and the odds of being in a tight-knit family versus a intermediate-knit. The results suggest that familism may protect against suicide behavior among Latinas via its influence on family environment.  相似文献   
648.
Chunk learning (the process by which a sequence is learned and retrieved from memory in smaller, decomposed units of information) has been postulated as the main learning mechanism underlying sequence learning (Perruchet & Pacton, 2006). However, the evidence for chunk formation has been elusive in the continuous serial reaction-time task, whereas other continuous, statistical processes of learning account well for the results observed in this task. This article proposes a new index to capture segmentation in learning, based on the variance of responding to different parts of a sequence. We assess the validity of this measure by comparing performance in a control group with that of another group in which color codes were used to induce a uniform segmentation. Results showed that evidence of chunking was obtained when the color codes were consistently coupled to responses, but that chunking was not maintained after the colors were removed.  相似文献   
649.
Here we try to offer a panoramic view on the evolution of the concept of introjection in Ferenczi's thinking, until its culmination in the last annotation of Notes and Fragments on December 26, 1932. In this final note, Ferenczi invented the neologism intropression in which he tried to articulate the notion of introjections with the devastating effects of violence and parental repression, and a definite way to conceive the analytical practice.  相似文献   
650.
Relations between voting choice and similarity in traits between voters and political candidates are examined in two studies. The first study was conducted in Spain, where the personalities of Mariano Rajoy and José Luis Rodríguez Zapatero were assessed. The second study was conducted in Italy, where the politicians assessed were Walter Veltroni and Silvio Berlusconi. Results show in both cases a similarity between voters' self-reported personality and their appraisals of the leaders of the party for which they voted. Similarity is generally higher with respect to traits that are the most distinctive for each platform and its leader. The findings show a higher similarity between voters and their leaders on the markers of agreeableness, such as "loyal" and "sincere." Findings hold across countries and political figures, demonstrating the role that personal characteristics of both voters and candidates play in orienting political preference.  相似文献   
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