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291.
Functional magnetic resonance imaging has emerged as a powerful tool for mapping the neurologic underpinnings of sensory, motor and cognitive function. Much of this evolution carries assumptions about the subject population under study and, in particular, the neurologic status of subjects entered into studies either as healthy controls or as belonging to a specific disease group. Recent reports of incidental MRI abnormalities in normal volunteers for fMRI studies have brought to attention a variety of practical challenges and ethical dilemmas for researchers, many of whom are not physicians and most of whom have no formal radiological training. We propose a minimum standard for consenting subjects in fMRI protocols, and consider strategies over the longer term that call for expert physician participation, archiving of incidental findings including false positives, and the adoption of guidelines for handling variation in neural activations or performance that appear outside expected norms. 相似文献
292.
The trajectory of suicidal behavior over time 总被引:5,自引:0,他引:5
Joiner TE 《Suicide & life-threatening behavior》2002,32(1):33-41
Some empirical work on genetic and prenatal factors in suicidality is presented. These factors may represent enduring predispositions that comprise risk for initial as well as later suicidal behavior. The existence of enduring predispositions does not preclude the possibility, however, that initial suicidal behavior sets processes into motion that spur later suicidal behavior. Based on past conceptual and empirical work, I suggest two psychological processes--cognitive sensitization and opponent processes--that may partly explain the link between past and future suicidal behavior. 相似文献
293.
Simon TR Anderso M Thompson MP Crosby A Sacks JJ 《Suicide & life-threatening behavior》2002,32(1):42-50
Data from a nationally representative sample of 5,238 U.S. adults were used to examine the extent to which physical assault victimization was associated with suicidal ideation or behavior (SIB). The results from multivariable logistic regression analyses indicate that physical assault victimization was positively associated with SIB after adjusting for sociodemographic characteristics and alcohol use (OR = 3.6; 95% CI = 2.4-5.5). Those who were injured during the most recent physical assault (OR = 2.7; 95% CI = 1.2-6.0) and those who were assaulted by a relative (OR = 3.4; 95% CI= 1.0-11.0) or intimate partner (OR = 7.7; 95% CI = 2.7-22.5) were significantly more like to report SIB than victims who were not injured or were assaulted by a stranger. Also, those who were victimized but not injured (OR = 5.6; 95% CI = 3.8-8.2) and those who were victimized by a stranger (OR = 2.9; 95% CI = 1.4-6.0) were more likely to report SIB than non-victims. These results highlight the need for legal, medical, mental health, and social service providers to address the co-occurrence of violent victimization and suicidal ideation, particularly, but not exclusively, victimization by family members and intimates. 相似文献
294.
The objective of this research was to test substance-related and non-substance-related psychiatric disorders as predictors of attempted suicide among adolescents. Ninety-six psychiatrically disordered suicide attempters were matched one-to-one to 96 psychiatrically disordered non-attempters on age, race, gender, and the presence/absence of major depression. Conditional logistic regression was used to test psychiatric risk factors for their power to predict attempted suicide among adolescents. Bipolar disorder, cocaine use disorders, and conduct disorder were found to be predictive of attempted suicide in univariate testing. Bipolar disorder, inhalant use disorders, cocaine use disorders, and hallucinogen use disorders were found to be predictive of attempted suicide, after adjusting for all other covariates. Loglinear analyses revealed high odds ratios associated with the comorbidities of alcohol use disorder with conduct disorder and drug use disorders with conduct disorder in both groups. Higher rates of cocaine use disorder/conduct disorder, hallucinogen use disorder/conduct disorder, and alcohol use disorder/ conduct disorder were found among suicide attempters. Evaluation of these particular comorbid conditions should be part of the adolescent suicide risk assessment. 相似文献
295.
Many researchers have hypothesized relationships between personality disorders and gender role (i.e., masculinity and femininity). However, research has not addressed if people who are masculine or feminine more often meet the criteria for personality disorders. The present study examined whether college students (N = 665, 60% women) higher in masculinity or femininity more often exhibited features of the 10 DSM-IV personality disorders. Feminine men exhibited more features of all the personality disorders except antisocial. Dependent traits were associated with higher femininity and lower masculinity. Antisocial traits were associated with masculinity. Both men and women who typically behaved consistent with their gender had more narcissistic and histrionic features, whereas participants who typically behaved unlike their gender had more features of the Cluster A personality disorders. 相似文献
296.
When timing the mind one should also mind the timing: biases in the measurement of voluntary actions
Trevena and Miller (2002, this issue) provide further evidence that readiness potentials occur in the brain prior to the time that participants claim to have initiated a voluntary movement, a contention originally forwarded by Libet, Gleason, Wright, and Pearl (1983). In their examination of this issue, though, aspects of their data lead them to question whether their measurement of the initiation of a voluntary movement was accurate. The current article addresses this concern by providing a direct analysis of biases in this task. This was done by asking participants to make subjective timing decisions regarding a stimulus that could be measured objectively. Our findings suggest that their timing task was indeed biased such that participants' tend to report events as happening approximately 70 ms later than they actually happened. Implications for the original Libet et al. claims are discussed. 相似文献
297.
Induction of long-term synaptic changes at one synapse can facilitate the induction of long-term plasticity at another synapse. Here we show that if Aplysia sensory neuron (SN) somata and their remote motor neuron (MN) synapses are simultaneously exposed to serotonin (5HT) pulses, which at either site alone are insufficient to induce long-term facilitation (LTF), processes activated at these sites interact to induce LTF. Coincident induction of LTF requires: (1) that the synaptic pulse occurs within a brief temporal window of the somatic pulse and (2) that local protein synthesis occurs immediately at the synapse, followed by delayed protein synthesis at the soma. LTF at the SN-MN synapses can also be induced with cell-wide application of repeated pulses of 5HT. However, these two forms of LTF differ mechanistically: (1) coincident LTF requires protein synthesis in the postsynaptic motor neuron, whereas repeated 5HT LTF does not, and (2) repeated 5HT LTF is accompanied by intermediate-term (3 h) facilitation, whereas coincident LTF is not. Thus LTF expressed in the same temporal domain can result from different underlying mechanisms. 相似文献
298.
The demands of an ongoing activity influence the success of event-based prospective memory 总被引:1,自引:0,他引:1
Four experiments were conducted to evaluate whether event-based prospective memory would be sensitive to the concurrent demands of the ongoing activity in which intention-related cues were embedded. In Experiments 1 and 2, random alternation between two judgments in the ongoing task reduced prospective memory as compared with having a single task throughout. In Experiment 3, participants' making two binary judgments on every trial resulted in worse prospective memory than did their making single four-alternative judgments. In Experiment 4, participants' making two related judgments resulted in better prospective memory than did their making two unrelated judgments. The results are consistent in spirit with a production rule account of the processing resources that are available when intention-related cues are encountered. Therefore, event-based prospective memory can inversely covary with the cognitive demands of the ongoing activity. 相似文献
299.
Waite TA 《Animal cognition》2002,5(4):209-214
Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness
cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice:
the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions
to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted
by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance
when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing.
To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected
during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant
increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected
to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were
prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings
are thus consistent with the adaptive-choice model.
Electronic Publication 相似文献
300.
O'Connor TS McCarroll-Butler P Meakes E Davis A Jadad A 《The journal of pastoral care & counseling : JPCC》2002,56(3):227-232
Using computer technology to identify the term "spiritual," these researchers present results of the 2306 citations and compare five criteria discovered with research reported in four pastoral counseling journals. The authors note the limitations of such a search and the possible implications of the findings for health care ministry. 相似文献