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21.
The COVID-19 pandemic brought new attention to the issues of food insecurity faced by individuals throughout the United States, a stressor exacerbated by disruptions to work status and supply chains. The burden of food insecurity likely carries consequences for whether individuals feel capable of pursuing their broad goals and life engagements; put differently, food insecurity may pose a threat to people perceiving a sense of purpose in life. The current study tested this claim across three samples taken during 2020 (n = 2009), 2021 (n = 1666), and 2022 (n = 1975). Participants completed inventories for perceived food insecurity, sense of purpose, depressive symptoms, and anxiety, among other measures. Results found consistent negative associations between food insecurity and sense of purpose across all three samples. In addition, food insecurity moderated associations between sense of purpose and depressive or anxiety symptoms. Sense of purpose was more strongly negatively associated with depressive and anxiety symptoms for those participants who reported no food insecurity. That said, sense of purpose remained negatively associated with psychological distress even among those reporting food insecurity.  相似文献   
22.
This series of studies examined U.S. individuals' use of specific emotion regulation/coping strategies during the early months of the COVID-19 pandemic, investigated the factor structure among strategies during this universally experienced stressor, and the extent to which these factors predicted engagement in COVID-related health-promoting behaviors. In Study 1, participants (N = 520) rated their use of 17 strategies for coping with pandemic-related stress during the past 24 h. Differences emerged in strategy use across demographic groups (age, race, income). Results of exploratory factor analysis suggest a factor structure grouping strategies in terms of goals beyond emotion regulation per se, rather than phases of the emotion process or a binary adaptive versus maladaptive distinction. In Study 2 (N = 264), participants reported daily on their coping strategy use and weekly on their engagement in COVID-specific health behaviors for 22 days. Results of confirmatory factor analysis replicate the factor structure found in Study 1. Some significant associations of coping strategy use with health-promoting behaviors were observed, but these were sporadic and largely involved baseline measures rather than predicting change over time. Theoretical and practical implications are discussed.  相似文献   
23.
Evidence for successive serial exhaustive searches was found in a task requiring detection of repeated letters in visually presented lists of varying length. The time per comparison was 25 msec. Important differences in processing appeared between instances of adjacent repeated letters and instances of nonadjacent repeated letters.  相似文献   
24.
It is very tempting to reduce Soviet economic decisions and structures to pragmatic factors and to discount the influence of ideology. Without overemphasizing the influence of the latter, it seems clear that what happens in the Soviet economy is influenced by Marxism-Leninism, even though there is no question of making concrete predictions.  相似文献   
25.
In choice-response tasks employing correction-procedure, error-correcting responses are typically found to be faster than equivalent correct responses. An experiment was made to compare error-correction RT under conditions of good and poor S-R compatibility in a two-choice task. After practice, variations in S-R compatibility producing significant variations in mean correct RT nevertheless have no effect on error-correction time. The contrast between this result, and one previously reported (Burns, 1965) leads to a re-discussion of the processes of error detection and correction.  相似文献   
26.
Some formal models of grading principles   总被引:1,自引:0,他引:1  
Patrick Suppes 《Synthese》1966,16(3-4):284-306
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27.
Patrick Grim 《Synthese》1993,94(3):409-428
Predicates are term-to-sentence devices, and operators are sentence-to-sentence devices. What Kaplan and Montague's Paradox of the Knower demonstrates is that necessity and other modalities cannot be treated as predicates, consistent with arithmetic; they must be treated as operators instead. Such is the current wisdom.A number of previous pieces have challenged such a view by showing that a predicative treatment of modalities neednot raise the Paradox of the Knower. This paper attempts to challenge the current wisdom in another way as well: to show that mere appeal to modal operators in the sense of sentence-to-sentence devices is insufficient toescape the Paradox of the Knower. A family of systems is outlined in which closed formulae can encode other formulae and in which the diagonal lemma and Paradox of the Knower are thereby demonstrable for operators in this sense.I am deeply indebted to Robert F. Barnes and Evan W. Conyers, without whom these ideas might not have germinated and certainly would not have grown. Many of the results offered here evolved in the course of mutual discussion and correspondence. I am also grateful to an anonymous reviewer forSynthese for many very helpful suggestions.The current paper contains the technical results promised in Footnote 25 of Grim (1988) and Footnote 26, Chapter 3, of Grim (1991).  相似文献   
28.
Effects of alcohol and extended practice on divided-attention performance   总被引:3,自引:0,他引:3  
The effects of alcohol and extended practice on divided attention were investigated using a visual tracking task and an auditory detection task. Subjects performed the tasks with and without alcohol, under single-task (S) and dual-task (D) conditions, both before and after they had received extended practice under single-task conditions without alcohol. Tracking accuracy improved with practice and was impaired under divided-attention conditions but was not affected by alcohol. Speed of detection was impaired by alcohol, improved by practice, and impaired by divided attention. Extended practice did not reduce the influence of alcohol. The effects of both alcohol and practice on speed of detection were significantly greater under dual-task conditions than under single-task conditions. Analysis of detection-task reaction times in terms of relative divided-attention costs, (D-S)/S, showed no effect of alcohol, but a highly significant reduction in costs with extended practice. It is concluded that (1) alcohol and practice can have quantitatively, but not qualitatively, similar effects on speeded performance, and (2) the effect of alcohol is not influenced by the attentional requirements of the task.  相似文献   
29.
Associate to any linear ordering on the integers the mapping whose value on n is the cardinality of {k<n; kn}: a purely combinatorial characterization for the mappings associated to the well-orderings is established.This work was partially supported by a CNRS grant PRC mathématiques and informatique.  相似文献   
30.
We modified the standard procedure for administering finger pressure pain in order to assess the extent to which subjects biased their reports of pain reduction when exposed to compliance-inducing instructions. Experiment 1 used only highly hypnotizable subjects and found that compliance-induced reductions in reported pain were about half as large as the reported reductions produced by hypnotic analgesia suggestions. Experiment 2 used low as well as high hypnotizables and administered hypnotic or nonhypnotic analgesia instructions and compliance instructions to the same subjects on separate pain trials. Reported pain reductions produced by hypnotic and nonhypnotic analgesia suggestions and those produced by compliance instructions were substantially and significantly correlated. Furthermore, hypnotizability correlated with compliance-induced reported pain reductions as highly as it correlated with the reported reductions produced by hypnotic analgesia suggestions. Among high hypnotizables (but not low hypnotizables) compliant responding was predicted by social desirability. The findings of both studies indicate that compliance strongly influences the reports of hypnotic and nonhypnotic analgesia proffered by high hypnotizables. The role of compliance in the pain reductions reported by low hypnotizables is less clear-cut.  相似文献   
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