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991.
Criterion-referenced (Livingston) and norm-referenced (Gilmer-Feldt) techniques were used to measure the internal consistency reliability of Folstein's Mini-Mental State Examination (MMSE) on a large sample (N = 418) of elderly medical patients. Two administration and scoring variants of the MMSE Attention and Calculation section (Serial 7s only and WORLD only) were investigated. Livingston reliability coefficients (rs) were calculated for a wide range of cutoff scores. As necessary for the calculation of the Gilmer-Feldt r, a factor analysis showed that the MMSE measures three cognitive domains. Livingston's r for the most widely used MMSE cutoff score of 24 was .803 for Serial 7s and .795 for WORLD. The Gilmer-Feldt internal consistency reliability coefficient was .764 for Serial 7s and .747 for WORLD. Item analysis showed that nearly all of the MMSE items were good discriminators, but 12 were too easy. True score confidence intervals should be applied when interpreting MMSE test scores. 相似文献
992.
The reliable digit span (RDS) performance of chronic pain patients with unambiguous spinal injuries and no evidence of exaggeration or response bias (n = 53) was compared to that of chronic pain patients meeting criteria for definite malingered neurocognitive dysfunction (n = 35), and a group of nonmalingering moderate-severe traumatic brain injury (TBI) patients (n = 69). The results demonstrated that scores of 7 or lower were associated with high specificity (> .90) and sensitivity (up to .60) even when moderate to severe TBI are included. Multiple studies have demonstrated that RDS scores of 7 or lower rarely occur in TBI and pain patients who are not intentionally performing poorly on cognitive testing. This study supports the use of the RDS in detecting response bias in neuropsychological patients complaining of pain as well as in the assessment of pain-related cognitive impairment in patients whose primary complaint is pain. 相似文献
993.
Reliable Digit Span (RDS) is an indicator used to assess the validity of cognitive test performance. Scores of 7 or lower suggest poor effort or negative response bias. The possibility that RDS scores are also affected by pain has not been addressed thus potentially threatening RDS specificity. The current study used cold pressor-induced pain to investigate the effect of pain on RDS scores. Sixty undergraduate volunteers randomly assigned to one of three conditions (control, simulator, pain) completed the Digit Span subtest from the Wechsler Adult Intelligence Scale-III from which the RDS is derived. No differences in RDS scores were found between the control and pain groups, and neither group scored below 8. Sixty-five percent of the simulator group scored 7 or below. These results suggest that RDS is not affected by pain, and scores of 7 or less in persons with pain can be more confidently attributed to negative response bias. 相似文献
994.
Participants’ eye movements to four objects displayed on a computer screen were monitored as the participants clicked on the
object named in a spoken instruction. The display contained pictures of the referent (e.g., a snake), a competitor that shared
features with the visual representation associated with the referent’s concept (e.g., a rope), and two distractor objects
(e.g., a couch and an umbrella). As the first sounds of the referent’s name were heard, the participants were more likely
to fixate the visual competitor than to fixate either of the distractor objects. Moreover, this effect was not modulated by
the visual similarity between the referent and competitor pictures, independently estimated in a visual similarity rating
task. Because the name of the visual competitor did not overlap with the phonetic input, eye movements reflected word-object
matching at the level of lexically activated perceptual features and not merely at the level of preactivated sound forms. 相似文献
995.
The study reported here examined whether size perception based on monocular distance cues is computed automatically. Participants
were presented with a picture containing distance cues, which was superimposed with a pair of digits differing in numerical
value. One digit was presented so as to be perceived as closer than the other. The digits were of similar physical size but
differed in their perceptual size. The participants’ task was to decide which digit was numerically larger. It was found that
the decision took longer and resulted in more errors when the perceptual size of the numerically larger digit was smaller
than the perceptual size of the numerically smaller digit. These results show that perceived size affects performance in a
task that does not require size or distance computation. Hence, for the first time, there is empirical support for the working
assumption of the visual perception approach that size perception based on monocular distance cues is computed automatically. 相似文献
996.
The cerebellar anterior lobe may play a critical role in the execution and proper timing of learned responses. The current study was designed to monitor Purkinje cell activity in the rabbit cerebellar anterior lobe after eyeblink conditioning, and to assess whether Purkinje cells in recording locations may project to the interpositus nucleus. Rabbits were trained in an interstimulus interval discrimination procedure in which one tone signaled a 250-msec conditioned stimulus-unconditioned stimulus (CS-US) interval and a second tone signaled a 750-msec CS-US interval. All rabbits showed conditioned responses to each CS with mean onset and peak latencies that coincided with the CS-US interval. Many anterior lobe Purkinje cells showed significant learning-related activity after eyeblink conditioning to one or both of the CSs. More Purkinje cells responded with inhibition than with excitation to CS presentation. In addition, when the firing patterns of all conditioning-related Purkinje cells were pooled, it appeared that the population showed a pattern of excitation followed by inhibition during the CS-US interval. Using cholera toxin-conjugated horseradish peroxidase, Purkinje cells in recording areas were found to project to the interpositus nucleus. These data support previous studies that have suggested a role for the anterior cerebellar cortex in eyeblink conditioning as well as models of cerebellar-mediated CR timing that postulate that Purkinje cell activity inhibits conditioned response (CR) generation during the early portion of a trial by inhibiting the deep cerebellar nuclei and permits CR generation during the later portion of a trial through disinhibition of the cerebellar nuclei. 相似文献
997.
Coantagonism of glutamate receptors and nicotinic acetylcholinergic receptors disrupts fear conditioning and latent inhibition of fear conditioning 下载免费PDF全文
The present study investigated the hypothesis that both nicotinic acetylcholinergic receptors (nAChRs) and glutamate receptors (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptors (AMPARs) and N-methyl-d-aspartate glutamate receptors (NMDARs)) are involved in fear conditioning, and may modulate similar processes. The effects of the nAChR antagonist mecamylamine administered alone, the AMPAR antagonist NBQX administered alone, and the NMDAR antagonist MK-801 administered alone on cued fear conditioning, contextual fear conditioning, and latent inhibition of cued fear conditioning were examined. In addition, the effects of coadministration of either mecamylamine and NBQX or mecamylamine and MK-801 on these behaviors were examined. Consistent with previous studies, neither mecamylamine nor NBQX administered alone disrupted any of the tasks. However, coadministration of mecamylamine and NBQX disrupted both contextual fear conditioning and latent inhibition of cued fear conditioning. In addition, coadministration of mecamylamine with a dose of MK-801 subthreshold for disrupting either task disrupted both contextual fear conditioning and latent inhibition of cued fear conditioning. Coadministration of mecamylamine and NBQX, and coadministration of mecamylamine with a dose of MK-801 subthreshold for disrupting fear conditioning had little effect on cued fear conditioning. These results suggest that nAChRs and glutamate receptors may support similar processes mediating acquisition of contextual fear conditioning and latent inhibition of fear conditioning. 相似文献
998.
To provide a better estimate of the prevalence of ADHD in adulthood, the authors complete a telephone survey of 966 randomly selected adults. They compute two diagnoses from the survey data. Participants meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for both childhood and adulthood are defined as narrow ADHD. Broad ADHD adds to that definition those meeting subthreshold criteria. Cronbach's alpha is .90 for the 18 DSM-IV symptoms in childhood and .88 when rated for current symptoms in adulthood. No one item unduly influences the reliability of the total score. The authors find similar results in separate analyses of hyperactive-impulsive and inattentive symptoms. They estimate prevalences of 2.9% for Narrow ADHD and 16.4% for Broad ADHD. Having ADHD is associated with lower levels of education and employment status. These findings suggest that adult ADHD is a common disorder associated with impaired functioning. 相似文献
999.
Liebowitz MR Ninan PT Schneier FR Blanco C 《CNS spectrums》2005,10(10):suppl13 1-11; discussion 12-3; quiz 14-5
Social anxiety disorder (SAD) is a common, chronic psychiatric disorder characterized by a persistent fear of social or performance situations in which embarrassment can occur. This disorder typically appears during the mid-adolescent years and is unremitting throughout life if not properly treated. SAD presents as two subtypes: the more common and debilitating generalized form, and the nongeneralized form, which consists predominantly of performance anxiety. The majority of patients with SAD have comorbid mental disorders, including mood, anxiety, and substance abuse. No single development theory has been proposed to account for the origins of SAD, although current understanding of the etiology of SAD posits an interaction between psychological and biological factors. Risk factors include environmental and parenting influences and dysfunctional cognitive and conditioning events in early childhood. The neurobiology of SAD appears to involve neurochemical dysfunction, as evidenced by studies of neuroreceptor imaging, neuroendocrine function, and profiles of response to specific medications. Clinical trials have demonstrated that benzodiazepines and antidepressants are effective in the treatment of SAD. The selective serotonin reuptake inhibitors are emerging as the first-line treatment for SAD, based on their proven safety, tolerability, and efficacy. Goals for ongoing future research include development of approaches to achieve remission, to convert nonresponders and partial responders to full responders, and to prevent relapse and maintain long-term efficacy. This monograph explores the epidemiology, clinical presentation, and differential diagnosis of SAD, with a focus on neural circuitry of social relationships and neurochemical dysfunction. The prevalence, rates of recognition and treatment, patterns of comorbidity, quality-of-life issues, and natural history of SAD are discussed as well as pharmacologic and psychosocial treatment strategies for SAD. 相似文献
1000.
Latent class analysis (LCA) provides a means of identifying a mixture of subgroups in a population measured by multiple categorical indicators. Latent transition analysis (LTA) is a type of LCA that facilitates addressing research questions concerning stage-sequential change over time in longitudinal data. Both approaches have been used with increasing frequency in the social sciences. The objective of this article is to illustrate data augmentation (DA), a Markov chain Monte Carlo procedure that can be used to obtain parameter estimates and standard errors for LCA and LTA models. By use of DA it is possible to construct hypothesis tests concerning not only standard model parameters but also combinations of parameters, affording tremendous flexibility. DA is demonstrated with an example involving tests of ethnic differences, gender differences, and an Ethnicity x Gender interaction in the development of adolescent problem behavior. 相似文献