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131.
Eavesdropping can be defined as the extraction of information from the interactions between other individuals. It provides a relatively cheap way of gathering relevant information for fitness enhancement. Here, we propose that obligate avian brood parasites, which always lay their eggs in foreign nests of individuals of other species, may eavesdrop on their host sexual signals to locate nests of high quality individuals in which to lay their parasitic eggs. Sexual signal variation can honestly signal parental quality. Thus, by eavesdropping on sexual signals, parasites may select high quality foster parents for their own offspring. Such a use of sexual signals within host populations by brood parasites differs from signal exploitation theory that proposes that parasite only use signals to locate potential host independently from signaller quality. Here, we review the avian literature concerning host choice within a host species by obligate avian brood parasites and find evidence for host selection within individuals of a host species on the basis of cues potentially functioning as sexually selected traits, or at least revealing parental abilities. We have also found support for the existence of benefits linked to host selection by avian brood parasites. Finally, one study reported on the attenuation of a sexual ornament in host populations under strong pressure by brood parasites. Most of these findings have been interpreted as evidence for host selection by avian brood parasites based on the conspicuousness of sexual signals. We suggest, however, that these findings may in fact reveal eavesdropping on host signalling performance by brood parasites which would use the information extracted to choose the better individuals among conspecifics of a given host. This provides a new perspective for the study of host selection in obligate brood parasites, and raises interesting questions for the study of animal cognition that would deserve experimental studies.  相似文献   
132.
A pilot study was carried out in university students to evaluate the effect of a health promotion program for eating disturbances and body dissatisfaction. A subgroup of 135 medical students of both sexes in their second year was selected. There were divided in three groups, high-risk students (EDI > 40) and low-risk students (EDI < 40) who participated in the program and nonparticipants as comparison group. Program had a total of 16 workshops of 90 min. A year later the different assessment measurements were compared, body image, attitudes and eating behaviours, psychopathological levels and self-esteem. Differences by gender were found on the impact of the intervention. The program presented a statistical significant improvement in body-image satisfaction, eating attitudes only in high-risk female students in the intervention group. This pilot program for eating disorder prevention in university populations can be considered effective, mainly in female populations at risk for developing an eating disorder.  相似文献   
133.
Although major depressive disorder (MDD) is associated with suicidal behaviors, some depressed individuals are not suicidal and others evidence various forms of suicidality. We thus investigated whether aspects of temperament and self-regulation of dysphoria represent risk factors for DSM-IV suicidality (recurrent thoughts of death, recurrent suicidal ideation, suicidal plan, and suicide attempt) in depressed youths. Using a sample of children with MDD (N = 407; ages 7-14 years), recruited from clinical sites across Hungary, we tested the hypotheses that: (a) suicidality is related to higher levels of trait negative emotionality as well as more maladaptive and fewer adaptive regulatory responses to dysphoria and (b) as the severity of suicidal behavior increases, levels of trait negative emotionality and dysfunctional emotion regulation also increase. We also explored if other aspects of temperament relate to suicidality. Children's DSM-IV diagnoses were based on semi-structured interviews and best-estimate psychiatric consensus. Parents independently provided ratings of their children's temperament, and children separately completed an inventory of emotion regulation (ER). Using multivariate models, we failed to confirm the hypothesized relations of negative trait emotionality and suicidality, but confirmed that high maladaptive and low adaptive ER response tendencies increase the odds of suicidal behaviors, above and beyond the risk posed by depressive illness severity. Unplanned interaction terms between temperament dimensions (other than negative emotionality) and ER suggested that at some high-extremes of temperament, ER has no impact on suicidality but in their absence, adaptive ER lowers the risk of suicidality. The practical implications of the findings are discussed.  相似文献   
134.
The present experiments tested whether endogenous and exogenous cues produce separate effects on target processing. In Experiment 1, participants discriminated whether an arrow presented left or right of fixation pointed to the left or right. For 1 group, the arrow was preceded by a peripheral noninformative cue. For the other group, the arrow was preceded by a central, symbolic, informative cue. The 2 types of cues modulated the spatial Stroop effect in opposite ways, with endogenous cues producing larger spatial Stroop effects for valid trials and exogenous cues producing smaller spatial Stroop effects for valid trials. In Experiments 2A and 2B, the influence of peripheral noninformative and peripheral informative cues on the spatial Stroop effect was directly compared. The spatial Stroop effect was smaller for valid than for invalid trials for both types of cues. These results point to a distinction between the influence of central and peripheral attentional cues on performance and are not consistent with a unitary view of endogenous and exogenous attention.  相似文献   
135.
An experimenter-administered intervention involving prompts, self-monitoring, permanent product collection, rewards for plaque reduction, and corrective feedback was used to improve the flossing skills of four 7- to 11-year-old children. Parents were subsequently trained in the reward and feedback procedures to facilitate maintenance. In a multiple baseline across subjects design, all four subjects snowed improvement in plaque between teeth during experimenter-administered intervention. Three subjects maintained low plaque levels during the 3- to 4-month parent-administered rewards and feedback follow-up condition. Improved plaque levels on nontargeted tooth surfaces also were observed. Pediatric dentistry applications are discussed.  相似文献   
136.
137.
The concept of polarity is pervasive in natural language. It relates syntax, semantics and pragmatics narrowly (Giannakidou, in: Maienborn, von Heusinger, Portner (eds.), Semantics: an international handbook of natural language meaning, De Gruyter Mouton, Berlin, 2011; Israel in The grammar of polarity: pragmatics, sensitivity, and the logic of scales, Cambridge studies in linguistics, Cambridge University Press, Cambridge, 2014), it refers to items of many syntactic categories such as nouns, verbs and adverbs. Neutral polarity items appear in affirmative and negative sentences, negative polarity items cannot appear in affirmative sentences, and positive polarity items cannot appear in negative sentences. A way of reasoning in Natural Language is through Natural Logic (van Benthem in Essays in logical semantics, vol. 29 of Studies in linguistics and philosophy, Reidel, Dordrecht, 1986; Language in action: categories, lambdas, and dynamic logic, vol. 130 of Studies in logic, Elsevier, Amsterdam, 1991). This logic is based on the concept of polarity in order to make the meaning of a sentence weaker o stronger without changing its truth value. There exist many proposals to compute polarity in the Natural Logic context, the most widely known are the ones by: van Benthem (1986, 1991), Sánchez-Valencia (Studies on natural logic and categorial grammar, Ph.D. thesis, Universiteit van Amsterdam, 1991), Dowty (Proceedings of the 4th conference on semantics and theoretical linguistics, Cornel University, CLC Publications, Rochester, 1994), and van Eijck (in: ten Cate, Zeevat (eds.), 6th international Tbilisi symposium on logic, language, and computation, Batumi, Georgia, Springer, 2007). If Natural Logic is going to be used, as an inferential mechanism between text fragments, in Natural Language Processing applications such as text summarization, question answering, and information extraction, it is a priority to know what the existing relationship among the aforementioned algorithms is; for example, to implement the most general. We show in this paper the equivalence among the analyzed algorithms, filling a gap in Natural Logic research, particularly in computing polarity, and the soundness of their algorithms.  相似文献   
138.
139.
A formative evaluation (consisting of two phases: a scoping literature review and a focus group with mental health professionals) was conducted to inform the design of a web-based intervention to prevent postpartum depression, in terms of its characteristics and content: the Be a Mom program. The results showed that the web-based intervention should be short-term, delivered postnatally, and grounded in cognitive-behavior therapy principles. Moreover, the intervention should include weekly sessions targeting basic contents: motherhood changes, reorganizations and emotional experience; cognitions, self-criticism, and self-compassion; parenting values, social support, and assertive communication skills; couple relationship, negotiation and conflict resolution skills; and postpartum depression signs and professional help-seeking. These results may improve the Be a Mom’s adequacy, implementation success, and effectiveness.  相似文献   
140.
Previous research has suggested that infants exhibit a preference for familiar over unfamiliar social groups (e.g., preferring individuals from their own language group over individuals from a foreign language group). However, because past studies often employ forced‐choice procedures, it is not clear whether infants' intergroup preferences are driven by positivity toward members of familiar groups, negativity toward members of unfamiliar groups, or both. Across six experiments, we implemented a habituation procedure to independently measure infants' positive and negative evaluations of speakers of familiar and unfamiliar languages. We report that by 1 year of age, infants positively evaluate individuals who speak a familiar language, but do not negatively evaluate individuals who speak an unfamiliar language (Experiments 1 and 2). Several experiments rule out lower‐level explanations (Experiments 3–6). Together these data suggest that children's early social group preferences may be shaped by positive evaluations of familiar group(s), rather than negative evaluations of unfamiliar groups.  相似文献   
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