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141.
Schulz D Topic B De Souza Silva MA Huston JP 《Neurobiology of learning and memory》2004,82(2):128-141
Extinction of escape behavior in the water maze due to the removal of the platform, was hypothesized to induce a negative state, including the development of immobility, which is held to reflect a state of "despair" when measured in the forced swimming test. 27 aged and 8 adult animals (26 and 3 months old Wistar rats, respectively) were tested in the water maze during nine days with a platform hidden, followed by 7 days of extinction trials with the platform absent. As expected, both age groups developed immobility over the extinction trials, with the aged showing more than the adults. To examine whether the age difference in immobility was related to performance differences during acquisition, the aged were subdivided into superior, intermediate and inferior learners (n = 9 per group) on the basis of overall times to platform during acquisition, and compared with each other and the adults. Results showed that the aged inferior learners displayed the highest levels of immobility among the aged. Immobility scores were then correlated with post-mortem neurotransmitter contents in the hippocampus and ventral striatum. In the ventral striatum, levels of immobility were correlated with levels of acetylcholine, dopamine and the metabolite dihydroxyphenylacetic acid in the aged, and with norepinephrine in the adults. The data support the hypothesis that multiple extinction trials in the water maze result in immobility that may indicate "behavioral despair," and that striatal neurotransmitter systems correlate with the degree of its expression. The concept of extinction-induced despair is held to provide the promise of a conceptual and empirical model of human depression that is the consequence of loss of reinforcers. 相似文献
142.
Bellissimo MI Kouzmine I Ferro MM de Oliveira BH Canteras NS Da Cunha C 《Neurobiology of learning and memory》2004,82(2):150-158
Adult male Wistar rats with a substantia nigra pars compacta (SNc) lesion induced by intranigral administration of 1 micromol 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were used as a model of early phase Parkinson's disease (PD). This lesion caused a partial depletion of striatal dopamine (DA). The animals were submitted to a spatial working memory version of the water maze task in which they had to find a hidden (submersed) platform using online-maintained information that the platform remains in the same place during four consecutive trials, but that it is moved to another place every training day. Left, but not right SNc-lesioned rats were impaired in finding the platform in the second trial. This result suggests that the left SNc plays a key role in spatial working memory. Control experiments ruled out the possibility that motor impairment, sensory neglect, and/or impairment in the mental representation of the contralateral spatial environment had affected performance of the SNc-lesioned rats. 相似文献
143.
Lawler CP Croen LA Grether JK Van de Water J 《Mental retardation and developmental disabilities research reviews》2004,10(4):292-302
The potential role of environmental factors in autism spectrum disorders (ASD) is an area of emerging interest within the public and scientific communities. The high degree of heritability of ASD suggests that environmental influences are likely to operate through their interaction with genetic susceptibility during vulnerable periods of development. Evaluation of the plausibility of specific neurotoxicants as etiological agents in ASD should be guided by toxicological principles, including dose-effect dependency and pharmacokinetic parameters. Clinical and epidemiological investigations require the use of sufficiently powered study designs with appropriate control groups and unbiased case ascertainment and exposure assessment. Although much of the existing data that have been used to implicate environmental agents in ASD are limited by methodological shortcomings, a number of efforts are underway that will allow more rigorous evaluation of the role of environmental exposures in the etiology and/or phenotypic expression of the disorder. Surveillance systems are now in place that will provide reliable prevalence estimates going forward in time. Anticipated discoveries in genetics, brain pathology, and the molecular/cellular basis of functional impairment in ASD are likely to provide new opportunities to explore environmental aspects of this disorder. 相似文献
144.
145.
Joerden JC 《Science and engineering ethics》2004,10(1):65-72
This article considers issues concerning cases where the use of placebo is lawful or is not lawful under aspects of German
criminal law. It will differentiate between cases of individual therapy and cases of supervised experiments within the scope
of medical tests. Thereby, it reveals that a medication of placebo with regard to an individual patient seems to be lawful
if there is no alternative possibility of a better treatment using a chemically effective medicine and if the limits of presumed
consent are complied with. On the other hand, in the context of the supervised experiment, the assignment of a patient to
a group treated with placebo is only lawful if the patient has been fully informed about the possibilities of a treatment
and if the patient has given consent to it.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003.
The author’s interests include International Criminal Law, Comparative Criminal Law and Philosophy of Law. 相似文献
146.
Three experiments were conducted examining unimodal and crossmodal effects of attention to motion. Horizontally moving sounds
and dot patterns were presented and participants’ task was to discriminate their motion speed or whether they were presented
with a brief gap. In Experiments 1 and 2, stimuli of one modality and of one direction were presented with a higher probability
( p = .7) than other stimuli. Sounds and dot patterns moving in the expected direction were discriminated faster than stimuli
moving in the unexpected direction. In Experiment 3, participants had to respond only to stimuli moving in one direction within
the primary modality, but to all stimuli regardless of their direction within the rarer secondary modality. Stimuli of the
secondary modality moving in the attended direction were discriminated faster than were oppositely moving stimuli. Results
suggest that attending to the direction of motion affects perception within vision and audition, but also across modalities. 相似文献
147.
The authors examined the links between two dimensions that have been useful in understanding cross-cultural differences and similarities, namely, individualism-collectivism (I-C) and value orientations. The authors examined the relations and parallels between the two variables by directly relating them and examining the patterns of relations that both have with a third variable, religiosity. Participants were 475 college students from the Philippines, the United States, and Turkey who responded to measures of horizontal and vertical I-C, value orientations, and religiosity. The authors found partial support for the parallels between I-C and value types, particularly for collectivism and conservative values. Moreover, religiosity was associated positively with conservative values and collectivism, across all three cultures. The authors found individualism to also relate to openness-to-change values, though the patterns were not as consistent as those that they found between collectivism and conservation. Differences and similarities emerged in links of I-C-values to religiosity across the three samples. 相似文献
148.
Shea MT Stout RL Yen S Pagano ME Skodol AE Morey LC Gunderson JG McGlashan TH Grilo CM Sanislow CA Bender DS Zanarini MC 《Journal of abnormal psychology》2004,113(4):499-508
In this study, the authors examined time-varying associations between schizotypal (STPD), borderline (BPD), avoidant (AVPD), or obsessive-compulsive (OCPD) personality disorders and co-occurring Axis I disorders in 544 adult participants from the Collaborative Longitudinal Personality Disorders Study. The authors tested predictions of specific longitudinal associations derived from a model of crosscutting psychobiological dimensions (L. J. Siever & K. L. Davis, 1991) with participants with the relevant Axis I disorders. The authors assessed participants at baseline and at 6-, 12-, and 24-month follow-up evaluations. BPD showed significant longitudinal associations with major depressive disorder and posttraumatic stress disorder. AVPD was significantly associated with anxiety disorders (specifically social phobia and obsessive-compulsive disorder). Two of the four personality disorders under examination (STPD and OCPD) showed little or no association with Axis I disorders. 相似文献
149.
Schmitt DP Alcalay L Allik J Angleitner A Ault L Austers I Bennett KL Bianchi G Boholst F Borg Cunen MA Braeckman J Brainerd EG Caral LG Caron G Casullo MM Cunningham M Daibo I De Backer C De Souza E Diaz-Loving R Diniz G Durkin K Echegaray M Eremsoy E Euler HA Falzon R Fisher ML Foley D Fry DP Fry S Ghayur MA Golden DL Grammer K Grimaldi L Halberstadt J Haque S Herrera D Hertel J Hoffmann H Hooper D Hradilekova Z Hudek-Kene-evi J Jaafar J Jankauskaite M Kabangu-Stahel H Kardum I Khoury B 《Journal of personality and social psychology》2004,86(4):560-584
150.
de Brugada I Hall G Symonds M 《Journal of experimental psychology. Animal behavior processes》2004,30(1):58-66
In 2 experiments, rats received flavor-aversion conditioning in which the unconditioned stimulus (US) was an orally consumed solution of lithium chloride (LiCl). The resulting aversion was not attenuated by giving preexposure to injections of LiCl, although such preexposure did attenuate aversions established using injected LiCl as the US (Experiment 1). This outcome suggests that blocking by injection-related cues is responsible for the US-preexposure effect observed in this situation. Experiment 2 confirmed this interpretation by showing that presenting such cues (by giving an injection of saline) at the time that the LiCl was drunk resulted in an attenuation of conditioning in animals preexposed to injections of LiCl. The US-preexposure effect obtained in these experiments can be explained solely in terms of blocking by injection cues, although other mechanisms may contribute to the effect seen in other flavor-aversion paradigms. 相似文献