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981.
Eric T. Poehlman, Ph.D., was an internationally recognized, tenured professor at the University of Vermont (UVM) in Burlington when, in October 2000, a junior member of Poehlman’s laboratory became convinced that he had altered data from a study on aging volunteers from the Burlington area. This suspicion developed into one of the most significant cases of scientific misconduct in the history of the US Department of Health and Human Services’ (HHS) Office of Research Integrity (ORI), launching a US Department of Justice (DOJ) civil and criminal fraud investigation and, eventually, to a much publicized guilty plea and felony conviction. In the end, Dr. Poehlman admitted to 54 findings of scientific misconduct made by the UVM and ORI, agreed to retract or correct ten of his publications and to exclude himself from federal procurement and nonprocurement transactions for life. The United States Government’s handling of this case was distinguished by a highly cooperative approach that integrated the resources of the US Attorney’s Office for the District of Vermont (USAO) and both ORI and the Office of the Inspector General (OIG) in HHS in the common goal of prosecuting research fraud. The content of this article represents the personal views of the authors and does not express the opinion or policy of DHHS or its components. A paper on this topic was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005.  相似文献   
982.
Dialectical Behavioral Therapy (DBT) was initially developed and evaluated as an outpatient treatment program for chronically suicidal individuals meeting criteria for borderline personality disorder (BPD). Within the last few years, several adaptations to specific settings have been developed. This study aims to evaluate a three-month DBT inpatient treatment program. Clinical outcomes, including changes on measures of psychopathology and frequency of self-mutilating acts, were assessed for 50 female patients meeting criteria for BPD. Thirty-one patients had participated in a DBT inpatient program, and 19 patients had been placed on a waiting list and received treatment as usual in the community. Post-testing was conducted four months after the initial assessment (i.e. four weeks after discharge for the DBT group). Pre-post-comparison showed significant changes for the DBT group on 10 of 11 psychopathological variables and significant reductions in self-injurious behavior. The waiting list group did not show any significant changes at the four-months point. The DBT group improved significantly more than participants on the waiting list on seven of the nine variables analyzed, including depression, anxiety, interpersonal functioning, social adjustment, global psychopathology and self-mutilation. Analyses based on Jacobson's criteria for clinically relevant change indicated that 42% of those receiving DBT had clinically recovered on a general measure of psychopathology. The data suggest that three months of inpatient DBT treatment is significantly superior to non-specific outpatient treatment. Within a relatively short time frame, improvement was found across a broad range of psychopathological features. Stability of the recovery after one month following discharge, however, was not evaluated and requires further study.  相似文献   
983.
Observing somebody performing an action has been shown to elicit neuronal activity in the premotor cortex. This paper investigated physiological effect of observing an effortful action at the peripheral level. As Autonomic Nervous System responses reflect central nervous system processes such as movement planning and programming, it was expected that observing an action would elicit a pattern of ANS responses matching those recorded during actual movement. 12 male subjects, ages 23 to 28 years (M = 25.5, SD = 1.9), were selected as they were experienced in weight lifting. They were asked to observe a squat movement followed by returning to the upright position under 3 different conditions: (i) observation of actual movement performed by somebody else, (ii) observation of a video of the subject himself (first-person video), and (iii) observation of a video of somebody else performing the same movement (third-person video). Moreover, each movement was observed when performed at 50% and 90% of each participant's personal best mark (% of the highest weight which could be lifted). Three ANS parameters were continuously recorded: skin resistance, temperature and heart rate. ANS responses varied as a function of movement intensity: autonomic responses recorded during movement observation at 90% were significantly higher and longer than those recorded during movement observation at 50%. Thus, autonomic responses were linked to the amount of observed effort. Conversely, no difference was found among the three conditions of observation. ANS responses from observation of actual movement were shown to resemble those recorded under the two conditions of video observation.  相似文献   
984.
Recent data indicate that the familiarity and the emotional expression of faces occur at an early stage of information processing. The goal of the present study was to determine whether these two aspects interact at the structural encoding stage as reflected by the N170 component of event-related potentials in tasks requiring the subjects either to identify whether the faces were familiar or the nature of the emotional expression. The results indicate that the neural responses to level of familiarity and emotional expression were observable at this early processing stage but without interacting. In particular, faces of personal importance to the subjects differed from those of less personal importance. Because familiarity did not interact with emotional expression at behavioral and electrophysiologic levels, our results support the contention of parallel and independent processing of faces.  相似文献   
985.
986.
Metabotropic glutamate receptors (mGluRs) are known to play a role in synaptic plasticity and learning. We have previously shown that mGluR7 deletion in mice produces a selective working memory (WM) impairment, while other types of memory such as reference memory remain unaffected. Since WM has been associated with Theta activity (6-12 Hz) in EEGs, and since EEG abnormalities have been observed in these mice before, we studied the effect of mGluR7 gene ablation on EEG activity in the hippocampus, in particular in the Theta range, during performance of a WM task. In an eight-arm maze with four arms baited, mGluR7 knock-out (KO) and wild-type mice committed the same number of reference memory errors, whereas KOs committed more WM errors. While performing the task, KO mice showed substantially higher Theta amplitudes, and the ratio of Theta to overall EEG power was much increased. No change was seen in the Delta (0-5 Hz), or Gamma (30-40 Hz) EEG bands compared with controls. When recording EEGs during periods of rest in the home cages, no difference was seen between groups. These findings suggest that mGluR7 is important for modulation and control of Theta activity. Since only WM was affected, and only the Theta range of EEG activity was altered, these results show a correlation between Theta rhythm and WM performance, and therefore support the concept that Theta activity in the hippocampus is involved in WM storage.  相似文献   
987.
We examined child psychiatric diagnoses, behavioral problems, overall symptom impairment, global psychological functioning, intellectual ability, and adaptive behavior in 83 sibling pairs whose mothers were diagnosed with a serious mental disorder. Sibling pairs were assessed for the extent to which they converged on the presence or absence of risk on each adverse outcome and then examined under conditions of high vs. low/moderate family stress. Consistent with the study hypotheses, we found that on each outcome assessed there was evidence for sibling convergence of risk. In addition, family stress was found to significantly moderate sibling risk convergence. The results are discussed in terms of their implications for understanding sibling convergence of risk in these families and for clinical and preventive intervention.  相似文献   
988.
We studied preparatory attention in patients suffering from frontotemporal dementia in the beginning stages of the disease, using an experimental test developed by LaBerge, Auclair, and Siéroff (2000). In this experimental test, a distracter can appear while subjects have to prepare to respond to a simple target. The probability that a distracter can appear in a trial is varied across three blocks. Normal controls show an increase of response times to targets (slope) as a function of the distracter probability, preparatory attention to the target is reduced by the increase of the distracter probability. Patients suffering from frontotemporal dementia show a slope of response times which is more than twice as large as the slope obtained by their matched controls. Such an abnormal increase of response times to targets is interpreted as a deficit in preparatory attention. Patients also show more omissions than controls. We suggest that this deficit in preparatory attention is related to the frontal lesion presented by the patients and can result in higher distractibility, a symptom frequently encountered in these patients.  相似文献   
989.
It is generally assumed that the lexical and phonological systems are involved in writing to dictation. In an experiment concerned with the writing of words and non-words to dictation, the handwriting of female students was registered using a digitising tablet. The data contradict the assumption that the phonological system represents an alexical process. Both words and non-words which were acoustically presented to the subjects were lexically parsed. The analysis of kinematic data revealed significant differences between the subjects' writing of words and non-words. The findings reveal gross disturbances of handwriting fluency during the writing of non-words. The findings of the experiment cannot be explained by the dual-process-theory.  相似文献   
990.
Blink and shrink: the effect of the attentional blink on spatial processing   总被引:3,自引:0,他引:3  
The detection or discrimination of the second of 2 targets in a rapid serial visual presentation (RSVP) task is often temporarily impaired-a phenomenon termed the attentional blink. This study demonstrated that the attentional blink also affects localization performance. Spatial cues pointed out the possible target positions in a subsequent visual search display. When cues were presented inside an attentional blink (as induced by an RSVP task), the observers' capacity to use them was reduced. This effect was not due to attention being highly focused, to general task switching costs, or to complete unawareness of the cues. Instead, the blink induced a systematic localization bias toward the fovea, reflecting what appears to be spatial compression.  相似文献   
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