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921.
Truchet B Manrique C Sreng L Chaillan FA Roman FS Mourre C 《Learning & memory (Cold Spring Harbor, N.Y.)》2012,19(7):282-293
Kv4 channels regulate the backpropagation of action potentials (b-AP) and have been implicated in the modulation of long-term potentiation (LTP). Here we showed that blockade of Kv4 channels by the scorpion toxin AmmTX3 impaired reference memory in a radial maze task. In vivo, AmmTX3 intracerebroventricular (i.c.v.) infusion increased and stabilized the EPSP-spike (E-S) component of LTP in the dentate gyrus (DG), with no effect on basal transmission or short-term plasticity. This increase in E-S potentiation duration could result from the combination of an increase in excitability of DG granular cells with a reduction of GABAergic inhibition, leading to a strong reduction of input specificity. Radioactive in situ hybridization (ISH) was used to evaluate the amounts of Kv4.2 and Kv4.3 mRNA in brain structures at different stages of a spatial learning task in naive, pseudoconditioned, and conditioned rats. Significant differences in Kv4.2 and Kv4.3 mRNA levels were observed between conditioned and pseudoconditioned rats. Kv4.2 and Kv4.3 mRNA levels were transiently up-regulated in the striatum, nucleus accumbens, retrosplenial, and cingulate cortices during early stages of learning, suggesting an involvement in the switch from egocentric to allocentric strategies. Spatial learning performance was positively correlated with the levels of Kv4.2 and Kv4.3 mRNAs in several of these brain structures. Altogether our findings suggest that Kv4 channels could increase the signal-to-noise ratio during information acquisition, thereby allowing a better encoding of the memory trace. 相似文献
922.
Keough ME Porter E Kredlow MA Worthington JJ Hoge EA Pollack MH Shear MK Simon NM 《Assessment》2012,19(2):257-259
The Panic Disorder Severity Scale (PDSS) is a clinician-administered measure of panic disorder symptom severity widely used in clinical research. This investigation sought to provide clinically meaningful anchor points for the PDSS both in terms of clinical severity as measured by the Clinical Global Impression-Severity Scale (CGI-S) and to extend its clinical meaningfulness by examining its association with quality of life. A total of 63 individuals with a primary diagnosis of panic disorder were assessed on completion of a 6- or 8-week psychotherapy or pharmacotherapy trial for the treatment of panic disorder. As expected, the PDSS was correlated with both the CGI-S and quality of life. These results provide further support for the validity and clinical utility of the PDSS and provide simple anchors to help guide the potential use of the PDSS scale to measure treatment progress in clinical practice. 相似文献
923.
Anagnostopoulos F Dimitrakaki C Fitzsimmons D Potamianos G Niakas D Tountas Y 《Journal of clinical psychology in medical settings》2012,19(2):147-164
Previous research has shown that, although routine mammography screening can reduce mortality from breast cancer, the use
of annual mammography screening remains well under 65%. In an effort to determine the factors that are associated with women’s
mammography behaviors, this study used the health belief model and the common-sense model of self-regulation as the theoretical
frameworks to explore health beliefs, illness representations, and women’s mammography practice. Data were obtained from a
nationally representative sample of 408 Greek women, 40 years of age or older, with no personal history of cancer. Three dependent
variables were considered: recent mammography, repeat mammography, and no mammogram during lifetime. Predictors included socio-demographic
and medical variables, perceived benefits of mammography screening, perceived barriers to mammography screening, self-efficacy,
as well as illness perceptions. Multivariate analyzes indicated that never having had a mammogram was more likely for women
who perceived fewer benefits and more barriers to mammography screening, had more negative emotional representations of breast
cancer, and had no private health insurance coverage. Factors associated with recent mammography were younger age, a good
knowledge of the recommended mammography screening interval, a family history of breast cancer, and use of patient reminders
for next mammogram. Adequate knowledge about the recommended mammography screening interval and higher values for breast cancer
worry were associated with an increased number of repeat lifetime mammograms. Implications of the results and suggestions
for future research are outlined. 相似文献
924.
Previous studies have suggested that the effects of extinction are response-specific. The present study investigated whether
an extinction treatment that eliminated goal tracking elicited by an appetitive conditioned stimulus (CS) would also eliminate
the conditioned reinforcing effects of that CS. Rats were first trained on a goal-tracking procedure in which an auditory
CS was paired with a food unconditioned stimulus. Animals learned to approach the location where the food was delivered. In
a subsequent phase, rats in one group received extinction training that eliminated the goal-tracking elicited by the CS. Rats
in the other group did not experience extinction of the food-paired CS. Then, both groups received a test for conditioned
reinforcement in which leverpresses resulted in the brief presentation of the stimulus previously paired with food. This stimulus
did not act as a conditioned reinforcer in the group that had been subjected to extinction training, but did serve as a conditioned
reinforcer in the group that did not experience extinction. These results indicate that the effects of extinction generalize
from the approach-eliciting to the conditioned reinforcing effects of an appetitive CS. 相似文献
925.
Noiville C 《Journal international de bioéthique》2012,23(2):165-72, 183-4
Because they gather huge quantities of human biological samples and information allowing for better understanding of diseases, biobanks appear as a very powerful tool for boosting both medical research and public health as a whole. Although France does not really appear as a leader in biobanking compared to China or UK, biobanks and other samples collections abound in our country and have then been regulated, even though french law does not use the term biobank as such. The present article gives an overview of the current legal framework and explores the remaining ethical and legal issues, concerning particularly the protection of donors, the sharing of biobanks content and the sharing of biobanks benefits. The article explains how these universal questions arise in this country and what answers (sometimes specific) they get or could get in the following years. 相似文献
926.
Osilla KC D'Amico EJ Díaz-Fuentes CM Lara M Watkins KE 《Cultural diversity & ethnic minority psychology》2012,18(2):192-202
Culturally and linguistically appropriate interventions are needed to reduce the risk of driving under the influence (DUI) recidivism among diverse populations. Using core elements of Motivational Interviewing, we developed a culturally relevant web-MI intervention (web-MI) in English and Spanish to serve as a standalone or adjunctive program in DUI educational settings and evaluated its feasibility and acceptability among clients with first-time DUI offenses. We conducted an iterative formative assessment using focus groups with staff (n = 8) and clients (n = 27), and usability interviews with clients (n = 21). Adapting MI for the web was widely accepted by staff and clients. Clients stated the web-MI was engaging, interactive and personal, and felt more comfortable than past classes and programs. Spanish-speaking clients felt less shame, embarrassment, and discomfort with the web-MI compared to other in-person groups. Results support the viability of web-MI for DUI clients at risk for recidivism and highlight the importance of adapting the intervention for diverse populations. Key decisions used to develop the web-MI are discussed. 相似文献
927.
McComas KA 《Science and engineering ethics》2012,18(4):699-717
Dependence in nanotechnology on external funding and academic-industry relationships has led to questions concerning its influence on research directions, as well as the potential for conflicts of interest to arise and impact scientific integrity and public trust. This study uses a survey of 193 nanotechnology industry and academic researchers to explore whether they share similar concerns. Although these concerns are not unique to nanotechnology, its emerging nature and the prominence of industry funding lend credence to understanding its researchers?? views, as these researchers are shaping the norms and direction of the field. The results of the survey show general agreement that funding sources are influencing research directions in nanotechnology; many respondents saw this influence in their own work as well as other researchers?? work. Respondents also agreed that funding considerations were likely to influence whether researchers shared their results. Irrespective of their institutional affiliation or funding status, twice as many researchers as not considered financial conflicts of interest a cause for concern, and three times as many respondents as not disagreed financial conflicts of interest in nanotechnology were uncommon. Only a third was satisfied with the way that conflicts of interest are currently managed and believed current procedures would protect the integrity of nanotechnology research. The results also found differences in views depending on researchers?? institutional affiliation and funding status. 相似文献
928.
Mouni Haoua Kouidri Christine Roland-Levy Sophie Berjot 《Psychologie du Travail et des Organisations》2012,18(2):142-159
Declarations of conciliation between private life and professional life based on three factors (sex, gender and positions) are studied in this paper. Our goals were (i) to show that conciliation between the different life spheres need to be considered both in terms of conflict and of life enrichment; (ii) and to demonstrate that the gender variable has combined effects with sex variables, as well as with positions variables, over the perception of work in relation to family interferences in terms of nature (conflict/enrichment), intensity and direction (family over work versus work over family). The study, conducted with 240 employees of low or high professional positions, based on SWING and BSRI scales, shows the moderating effect of gender on the perceptions of conciliation, whether enriching or conflicting. Our results also allow us to conclude that congruent adjustment (masculine domination) of the levels of our three factors constitute a protecting factor for employees, while an incongruent adjustment can constitute a risk factor, this being especially verified for women. 相似文献
929.
In the current eye‐tracking study, we explored whether 12‐month‐old infants can predict others' social preferences. We showed infants scenes in which two characters alternately helped or hindered an agent in his goal of climbing a hill. In a control condition, the two characters moved up and down the hill in identical ways to the helper and hinderer but did not make contact with the agent; thus, they did not cause him to reach or not reach his goal. Following six alternating familiarization trials of helping and hindering interactions (help–hinder condition) or up and down interactions (up–down condition), infants were shown one test trial in which they could visually anticipate the agent approaching one of the two characters. As predicted, infants in the help–hinder condition made significantly more visual anticipations toward the helping than hindering character, suggesting that they predicted the agent to approach the helping character. In contrast, infants revealed no difference in visual anticipations between the up and down characters. The up–down condition served to control for low‐level perceptual explanations of the results for the help–hinder condition. Thus, together the results reveal that 12‐month‐old infants make predictions about others' behaviour and social preferences from a third‐party perspective. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
930.
The present study investigates the effects of trait anxiety on the neural efficiency of working memory component functions (manipulation vs. maintenance) in the absence of threat-related stimuli. For the manipulation of affectively neutral verbal information held in working memory, high- and low-anxious individuals (N = 46) did not differ in their behavioral performance, yet trait anxiety was positively related to the neural effort expended on task processing, as measured by BOLD signal changes in fMRI. Higher levels of anxiety were associated with stronger activation in two regions implicated in the goal-directed control of attention--that is, right dorsolateral prefrontal cortex (DLPFC) and left inferior frontal sulcus--and with stronger deactivation in a region assigned to the brain's default-mode network--that is, rostral-ventral anterior cingulate cortex. Furthermore, anxiety was associated with a stronger functional coupling of right DLPFC with ventrolateral prefrontal cortex. We interpret our findings as reflecting reduced processing efficiency in high-anxious individuals and point out the need to consider measures of functional integration in addition to measures of regional activation strength when investigating individual differences in neural efficiency. With respect to the functions of working memory, we conclude that anxiety specifically impairs the processing efficiency of (control-demanding) manipulation processes (as opposed to mere maintenance). Notably, this study contributes to an accumulating body of evidence showing that anxiety also affects cognitive processing in the absence of threat-related stimuli. 相似文献