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61.
Using children's naïve theory of biology as a framework, this study investigated children's developing understanding of illness by examining their generalisation of illness to biological and non‐biological categories. In addition to differences associated with age, the children's health status was investigated for any possible linkwith their understanding. Healthy and chronically‐ill children, aged 4–11 years, were randomly assigned to one of three conditions, according to which exemplar (child, dog or duck) was described as suffering from an imaginary illness. Using a card‐sorting technique, the children assessed whether each entity out of 30 entities (five representatives in each of six categories: humans, mammals, non‐mammals, birds, plants and artifacts) could be afflicted by that illness. The children's generalisations indicated a grasp of the distinctiveness of the various categories, although they seemed less certain about the biological status of plants. Furthermore, the type of exemplar on which the children had been taught influenced their responses. However, the children's reasoning appeared unaffected by their health status and largely unaffected by age or gender. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
62.
Raising an adolescent or adult child with a developmental disability confers exceptional caregiving challenges on parents. We examined trajectories of 2 indicators of emotional well-being (depressive symptoms and anxiety) in a sample of primarily Caucasian mothers (N = 379; M age = 51.22 years at Time 1) of adolescent and adult children with an autism spectrum disorder (ASD; M age = 21.91 years at Time 1, 73.2% male). We also investigated within-person associations of child context time-varying covariates (autism symptoms, behavior problems, residential status) and maternal context time-varying covariates (social support network size and stressful family events) with the trajectories of emotional well-being. Data were collected on 5 occasions across a 10-year period. Average patterns of stable (depressive symptoms) and improved (anxiety) emotional well-being were evident, and well-being trajectories were sensitive to fluctuations in both child and maternal context variables. On occasions when behavior problems were higher, depressive symptoms and anxiety were higher. On occasions after which the grown child moved out of the family home, anxiety was lower. Anxiety was higher on occasions when social support networks were smaller and when more stressful life events were experienced. These results have implications for midlife and aging families of children with an ASD and those who provide services to these families.  相似文献   
63.
The role of the cerebellum in eyeblink conditioning is well established. Less work has been done to identify the necessary conditioned stimulus (CS) pathways that project sensory information to the cerebellum. A possible visual CS pathway has been hypothesized that consists of parallel inputs to the pontine nuclei from the lateral geniculate nucleus (LGN), superior colliculus (SC), pretectal nuclei, and visual cortex (VCTX) as reported by Koutalidis and colleagues in an earlier paper. The following experiments examined whether electrical stimulation of neural structures in the putative visual CS pathway can serve as a sufficient CS for eyeblink conditioning in rats. Unilateral stimulation of the ventral LGN (Experiment 1), SC (Experiment 2), or VCTX (Experiment 3) was used as a CS paired with a periorbital shock unconditioned stimulus. Stimulation was delivered to the hemisphere contralateral to the conditioned eye. Rats in all experiments were given five 100-trial sessions of paired or unpaired eyeblink conditioning with the stimulation CS followed by three paired sessions with a light CS. Stimulation of each visual area when paired with the unconditioned stimulus supported acquisition of eyeblink conditioned responses (CRs) and substantial savings when switched to a light CS. The results provide evidence for a unilateral parallel visual CS pathway for eyeblink conditioning that includes the LGN, SC, and VCTX inputs to the pontine nuclei.Pavlovian eyeblink (eyelid closure and nictitating membrane movement) conditioning is established by pairing a conditioned stimulus (CS), usually a tone or light, with an unconditioned stimulus (US) that elicits the eyeblink reflex. The eyeblink conditioned response (CR) emerges over the course of paired training, occurs during the CS, and precedes the US (Gormezano et al. 1962; Schneiderman et al. 1962). Neurobiological investigations of Pavlovian eyeblink conditioning have primarily focused on the cerebellum, which is the site of memory formation and storage (Thompson 2005). The anterior interpositus nucleus is necessary for acquisition and retention of the eyeblink CR (Lavond et al. 1985; Krupa and Thompson 1997; Freeman Jr. et al. 2005; Thompson 2005; Ohyama et al. 2006). Lobule HVI and the anterior lobe of the cerebellar cortex (lobules I–V) contribute to acquisition, retention, and timing of the CR (McCormick and Thompson 1984; Perrett et al. 1993; Perrett and Mauk 1995; Attwell et al. 1999, 2001; Medina et al. 2000; Nolan and Freeman Jr. 2005; Nolan and Freeman 2006). The brainstem nuclei that comprise the proximal ends of the CS and US input pathways to the cerebellum have also been identified.The pontine nuclei (PN) and inferior olive (IO) receive CS and US information, respectively, and are the primary sensory relays into the interpositus nucleus and cerebellar cortex (Thompson 2005). Conditioned stimulus information converges in the PN, which receives projections from lower brainstem, thalamus, and cerebral cortex (Glickstein et al. 1980; Brodal 1981; Schmahmann and Pandya 1989; Knowlton et al. 1993; Campolattaro et al. 2007). The lateral pontine nuclei (LPN) are the sources of auditory CS information projected into the cerebellum. Lesions of the LPN block CR retention to a tone CS, but have no effect on CRs to a light CS (Steinmetz et al. 1987). Thus, CS inputs from different sensory modalities may be segregated at the level of the PN. Neurons in the PN project CS information into the contralateral cerebellum via mossy fibers in the middle cerebellar peduncle that synapse primarily on granule cells in the cerebellar cortex and on neurons in the deep nuclei (Bloedel and Courville 1981; Brodal 1981; Steinmetz and Sengelaub 1992). Stimulation of the PN acts as a supernormal CS supporting faster CR acquisition than conditioning with peripheral stimuli (Steinmetz et al. 1986, 1989; Rosen et al. 1989; Steinmetz 1990; Tracy et al. 1998; Freeman Jr. and Rabinak 2004). The primary focus of these experiments was to investigate the most proximal components of the CS pathway in eyeblink conditioning. There has been less emphasis on identifying the critical CS pathways that project information to the PN.Recent studies using lesions, inactivation, stimulation, and neural tract tracing have provided evidence that the auditory CS pathway that is necessary for acquisition and retention of eyeblink conditioning is comprised of converging inputs to the medial auditory thalamic nuclei (MATN), and a direct ipsilateral projection from the MATN to the PN (Halverson and Freeman 2006; Campolattaro et al. 2007; Freeman et al. 2007; Halverson et al. 2008). Unilateral lesions of the MATN, contralateral to the conditioned eye, block acquisition of eyeblink CRs to a tone CS but have no effect on conditioning with a light CS (Halverson and Freeman 2006). Inactivation of the MATN with muscimol blocks acquisition and retention of CRs to an auditory CS, and decreases metabolic activity in the PN (Halverson et al. 2008). The MATN has a direct projection to the PN and stimulation of the MATN supports rapid CR acquisition (Campolattaro et al. 2007). Our current model of the auditory CS pathway consists of converging inputs to the MATN, and direct unilateral thalamic input to the PN (Halverson et al. 2008).Less work has been done to identify the visual CS pathway necessary for eyeblink conditioning. A possible parallel visual CS pathway has been hypothesized, which includes parallel inputs to different areas of the PN from the lateral geniculate nucleus (LGN), superior colliculus (SC), visual cortex (VCTX), and pretectal nuclei (Koutalidis et al. 1988). In the Koutalidis et al. study, lesions of the LGN, SC, VCTX, or pretectal nuclei alone had only a partial effect on CR acquisition with a light CS. Lesions of any two of these structures together produced a more severe impairment on acquisition and combined lesions of all of these areas completely blocked CR acquisition to a light CS (Koutalidis et al. 1988). Each visual area investigated in the Koutalidis et al. study has a direct projection to the PN that could be important for eyeblink conditioning. The ventral LGN projects to the medial, and to a lesser extent, the lateral PN (Graybiel 1974; Wells et al. 1989). The superficial, intermediate, and deep layers of SC send projections to both the dorsomedial and dorsolateral PN (Redgrave et al. 1987; Wells et al. 1989). The VCTX has a direct projection to the rostral and lateral portions of the PN (Glickstein et al. 1972; Baker et al. 1976; Mower et al. 1980; Wells et al. 1989). The pretectal nuclei also have a direct projection to both the medial and lateral PN (Weber and Harting 1980; Wells et al. 1989). However, stimulation of the anterior pretectal nucleus is not an effective CS for eyeblink conditioning (Campolattaro et al. 2007). The failure to establish conditioning with stimulation of the anterior pretectal nucleus as a CS suggests that there may be differences in the efficacy of the various visual inputs to the PN for cerebellar learning. The following experiments investigated the sufficiency of stimulation of the LGN, SC, or primary VCTX as a CS for eyeblink conditioning in rats.  相似文献   
64.
The consequences of the early onset of substance use on later outcomes are a public health concern. In the present study, we examined neighborhood risk factors as a possible predictor of the onset of substance use in adolescents. In addition, we assessed the potential buffering effects of parental supervision on the relationship between neighborhood risk and the onset of substance use. The participants included 95, abstinent, African American 6th graders (mean age = 11.5 years) who enrolled in one site of a national, multi-site study of high-risk youth participating in a federally sponsored program. In the 6th and 8th grades, the participants completed self-report measures regarding substance use, perceived negative neighborhood activities and parental supervision. Logistic regression analyses demonstrated that both exposure to negative neighborhood activities and low parental supervision increase the onset of substance use by the 8th grade among African American adolescents. However, the results suggested that parents can protect their adolescents from the impact of exposure to adverse neighborhood factors by providing appropriate supervision.  相似文献   
65.
Background. Although class attendance is linked to academic performance, questions remain about what determines students' decisions to attend or miss class. Aims. In addition to the constructs of a common decision‐making model, the theory of planned behaviour, the present study examined the influence of student role identity and university student (in‐group) identification for predicting both the initiation and maintenance of students' attendance at voluntary peer‐assisted study sessions in a statistics subject. Sample. University students enrolled in a statistics subject were invited to complete a questionnaire at two time points across the academic semester. A total of 79 university students completed questionnaires at the first data collection point, with 46 students completing the questionnaire at the second data collection point. Method. Twice during the semester, students' attitudes, subjective norm, perceived behavioural control, student role identity, in‐group identification, and intention to attend study sessions were assessed via on‐line questionnaires. Objective measures of class attendance records for each half‐semester (or ‘term’) were obtained. Results. Across both terms, students' attitudes predicted their attendance intentions, with intentions predicting class attendance. Earlier in the semester, in addition to perceived behavioural control, both student role identity and in‐group identification predicted students' attendance intentions, with only role identity influencing intentions later in the semester. Conclusions. These findings highlight the possible chronology that different identity influences have in determining students' initial and maintained attendance at voluntary sessions designed to facilitate their learning.  相似文献   
66.
Humans exchange a range of nonverbal social signals in every interaction. It is an open question whether people use these signals, consciously or unconsciously, to guide social behavior. This experiment directly tested whether participants could learn to predict another person’s behavior using nonverbal cues in a single interaction, and whether explicit knowledge of the cue-outcome relationship was necessary for successful prediction. Participants played a computerized game of rock-paper-scissors against an avatar they believed was another participant. Sometimes the avatar generated a predictive facial cue before the play. On these trials, participants’ win-frequency increased over time, even if they did not acquire explicit knowledge of the predictive cue. The degree to which participants could predict the avatar (wins on cued trials) related to their self-reported liking of the avatar. These findings demonstrate the importance of implicit associative learning mechanisms in guiding social behavior on a moment-to-moment basis during interaction.  相似文献   
67.
Individuals with mathematics anxiety have been found to differ from their non-anxious peers on measures of higher-level mathematical processes, but not simple arithmetic. The current paper examines differences between mathematics anxious and non-mathematics anxious individuals in more basic numerical processing using a visual enumeration task. This task allows for the assessment of two systems of basic number processing: subitizing and counting. Mathematics anxious individuals, relative to non-mathematics anxious individuals, showed a deficit in the counting but not in the subitizing range. Furthermore, working memory was found to mediate this group difference. These findings demonstrate that the problems associated with mathematics anxiety exist at a level more basic than would be predicted from the extant literature.  相似文献   
68.
Distress tolerance (DT), the perceived or actual ability to tolerate negative emotional or physical states, is inversely related to posttraumatic stress disorder (PTSD) symptoms in civilian, community samples. No studies to date have examined the relationship between DT and PTSD in clinical samples of veterans with a comorbid diagnosis of PTSD and a substance use disorder (SUD). Thus, the present study examined the relationship between DT and PTSD in a sample of predominately African American, male veterans (n = 75) diagnosed with comorbid PTSD and SUD (according to a structured clinical interview). Results of hierarchical linear regression models indicated that DT was inversely related to total PTSD symptom severity score, above and beyond depressive symptoms and SUD severity. Of the 4 symptom clusters, DT was inversely associated with intrusions and hyperarousal. These findings are discussed in light of previous work with civilian samples. Determining whether treatment incorporating DT skills would be useful for veterans undergoing PTSD treatment should be evaluated.  相似文献   
69.
Identifying the factors associated with mental health services use (MHSU) is an important step in developing strategies to improve services access and delivery. The aims of the present study were to (a) identify personality and individual difference characteristics associated with MHSU intentions within the framework of the Theory of Planned Behavior (TPB) and (b) explore complex relationships that might exist between these characteristics and determinants of MHSU intentions identified in TPB, including attitudes, subjective norms, and perceived behavioral control. Data for 244 Canadian Armed Forces recruits who completed a MHSU questionnaire following mental health training were linked to personality data collected earlier. Multivariate analyses showed that the relationship between agreeableness and MHSU intentions was mediated by instrumental attitudes and subjective norms. The relationship between hardiness and MHSU intentions was mediated by subjective norms and self-efficacy. Findings suggest it may be worthwhile to consider mental health education initiatives to improve MHSU.  相似文献   
70.
According to interdependence theory, interpersonal situations that vary in their surface characteristics can be united by similarities in their underlying structure. Likewise, factor analytic approaches to personality combine many traits into a small number of factors. In the current research, we use interdependence theory and existing factor analyses of personality traits to measure people's lay theories about the ways traits and situations interact. We predict that traits representative of honesty–humility/virtue will be rated as more relevant to situations with non‐correspondent outcomes (a gain in one person's outcomes is associated with a loss in the other person's outcomes) than to situations with correspondent outcomes (a gain in one person's outcomes is associated with a gain in the other person's outcomes). Conversely, we predict that traits representative of agreeableness will be rated as more relevant to situations with correspondent outcomes than to situations with non‐correspondent outcomes. An experiment found the expected trait X situation interaction revealing that subjects expect certain types of traits to be most relevant to specific types of situations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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