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641.
In group-living animals, it is adaptive to recognize conspecifics on the basis of familiarity or group membership as it allows association with preferred social partners and avoidance of competitors. However, animals do not only associate with conspecifics but also with heterospecifics, for example in mixed-species flocks. Consequently, between-species recognition, based either on familiarity or even individual recognition, is likely to be beneficial. The extent to which animals can distinguish between familiar and unfamiliar heterospecifics is currently unclear. In the present study, we investigated the ability of eight carrion crows to differentiate between the voices and calls of familiar and unfamiliar humans and jackdaws. The crows responded significantly more often to unfamiliar than familiar human playbacks and, conversely, responded more to familiar than unfamiliar jackdaw calls. Our results provide the first evidence that birds can discriminate between familiar and unfamiliar heterospecific individuals using auditory stimuli.  相似文献   
642.
In order to maintain group cohesion, many social mammals and birds regularly produce close calls. In some primate species, close calls appear to have a dual function: calls addressed at a broad class of targets serve to maintain group cohesion, whereas the same calls directed at a specific target serve to regulate subsequent social interactions. Redfronted lemurs (Eulemur rufifrons) produce different types of close calls: grunts, long grunts, hoos and meows. In order to study the function of these calls, we conducted focal observations and vocal recordings from eight adult males and females out of four social groups in Kirindy Forest, Western Madagascar. Redfronted lemurs produce long grunts, hoos and meows at relatively low rates during foraging, resting or group movements, respectively. Grunts were given most often and more or less constantly during foraging and traveling. Calling rate increased when the risk of separation increased and may thus promote group cohesion. Grunts given during approaches of other group members resulted more often in friendly interactions than approaches that were not accompanied by a grunt. Thus, redfronted lemurs produce specific but also generic contact calls, whereas the latter calls have a dual function that varies depending on the addressed audience: they act as an auditory beacon to maintain group cohesion and serve as signals of benign intent to avoid costly conflicts and facilitating social interactions.  相似文献   
643.
Three fundamental fears-anxiety sensitivity, fear of negative evaluation, and illness/injury sensitivity-are considered integral components of anxiety-related psychopathology and also bear connections with chronic pain. Scales measuring the first two fears, the Anxiety Sensitivity Index and the Fear of Negative Evaluation Scale, have been translated into German; however, the nine-item Illness/Injury Sensitivity Index-Revised (ISI-R) that measures fears of injury and illness has not been available in German language yet. The aim of this study therefore was a translation of the ISI-R into German language and an initial validation of the translated scale in two different samples. The German ISI-R was translated by both professionals and laypersons, and a final version was decided on by consensus. In Study 1, participants included 96 undergraduate students (85% women) who completed the German version of the ISI as part of a larger study. An exploratory factor analysis with oblique rotation was conducted and suggested a two-factor-solution with one factor representing fears of illness and the other fears of injury. This factor structure was confirmed via a confirmatory factor analysis (CFA) in Study 2. Participants included 117 community members (79% women). Convergent validity was supported using a visual analogue scale for fear of illness in both samples and the German translation of the Whiteley Index in Study. Overall, the results supported the German translation of the ISI-R. Comprehensive results, limitations, and directions for future research are discussed.  相似文献   
644.
Temporal performance parameters vary across the visual field. Their topographical distributions relative to each other and relative to basic visual performance measures and their relative change over the life span are unknown. Our goal was to characterize the topography and age-related change of temporal performance. We acquired visual field maps in 95 healthy participants (age: 10?C90?years): perimetric thresholds, double-pulse resolution (DPR), reaction times (RTs), and letter contrast thresholds. DPR and perimetric thresholds increased with eccentricity and age; the periphery showed a more pronounced age-related increase than the center. RT increased only slightly and uniformly with eccentricity. It remained almost constant up to the age of 60, a marked change occurring only above 80. Overall, age was a poor predictor of functionality. Performance decline could be explained only in part by the aging of the retina and optic media. In Part II, we therefore examine higher visual and cognitive functions.  相似文献   
645.
646.
Patients with borderline personality disorder (BPD) suffer from affective instability, impulsivity, and identity disturbance which particularly manifest in an unstable or insecure self-image. One main problem for studies of core psychopathology in BPD is the complex subject of identity disturbance and self-image. The purpose of this study was to investigate the self-image of BPD patients with a qualitative research approach. Twelve patients with BPD were compared to 12 patients with remitted major depressive disorder (MDD) without personality disorder, using the Structured Interview of Personality Organization (STIPO). The transcribed interviews were analyzed using a combination of content analysis and grounded theory. BPD patients described themselves predominantly as helpful and sensitive; reported typical emotions were sadness, anger, and anxiety. MDD patients on the other hand reported numerous and various characteristics and emotions, including happiness, as well as sadness and anxiety. Other persons were characterized by the BPD group as egoistic and satisfied, while the MDD group described others as being balanced and secretive. BPD patients displayed an altruistic, superficial, and suffering self-image. Aggressive tendencies were only seen in other persons. Our findings support the concept of a self and relationship disturbance in BPD which is highly relevant for psychotherapy treatment.  相似文献   
647.
The aim of this study was to analyze the exploratory and confirmatory structure, as well as other psychometric properties, of the Cuestionario de Problemas de Convivencia Escolar (CPCE; in Spanish, the Questionnaire on School Maladjustment Problems [QSMP]), using a sample of Spanish adolescents. The instrument was administered to 60 secondary education teachers (53.4% females and 46.6% males) between the ages of 28 and 54 years (M= 41.2, SD= 11.5), who evaluated a total of 857 adolescent students. The first-order exploratory factor analysis identified 7 factors, explaining a total variance of 62%. A second-order factor analysis yielded three dimensions that explain 84% of the variance. A confirmatory factor analysis was subsequently performed in order to reduce the number of factors obtained in the exploratory analysis as well as the number of items. Lastly, we present the results of reliability, internal consistency, and validity indices. These results and their implications for future research and for the practice of educational guidance and intervention are discussed in the conclusions.  相似文献   
648.
Following several decades of research on native language (L1) processing, psycholinguists have more recently begun to investigate how non-native language (L2) speakers comprehend and process language in real time. Regarding the traditional assumption that L2 learners have 'difficulty with grammar', this new research has revealed some unexpected similarities and differences between L1 and L2 processing. Specifically, it appears that L2 processing can become native-like in some linguistic subdomains (including certain aspects of grammar) but that L1 and L2 processing differences persist in the domain of complex syntax, even in highly proficient L2 speakers. Thus, more subtle linguistic distinctions seem to be required to understand the nature of non-native language processing.  相似文献   
649.
Children often make impulsive choices, and previous research has shown that access to activities during the delay may enhance self‐control (e.g., Newquist, Dozier, & Neidert, 2012). The purpose of the current study was to extend the results of Newquist et al. (2012) by comparing the effects of access to low‐preference, moderate‐preference, and high‐preference toys during delays. Results showed that (a) all toys increased self‐control for 2 participants when toys were available for all choice options and (b) high‐preference toys (and sometimes moderate‐preference toys) increased self‐control for 3 participants when the toys were available only for large delayed choices.  相似文献   
650.
Animal Cognition - In this review, we have analyzed the studies on the “mismatch paradigm” or “contrasting paradigm”, in which the word indicates an intent that is opposite...  相似文献   
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