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201.
Behavioral momentum theory relates resistance to change of responding in a multiple-schedule component to the total reinforcement obtained in that component, regardless of how the reinforcers are produced. Four pigeons responded in a series of multiple-schedule conditions in which a variable-interval 40-s schedule arranged reinforcers for pecking in one component and a variable-interval 360-s schedule arranged them in the other. In addition, responses on a second key were reinforced according to variable-interval schedules that were equal in the two components. In different parts of the experiment, responding was disrupted by changing the rate of reinforcement on the second key or by delivering response-independent food during a blackout separating the two components. Consistent with momentum theory, responding on the first key in Part 1 changed more in the component with the lower reinforcement total when it was disrupted by changes in the rate of reinforcement on the second key. However, responding on the second key changed more in the component with the higher reinforcement total. In Parts 2 and 3, responding was disrupted with free food presented during intercomponent blackouts, with extinction (Part 2) or variable-interval 80-s reinforcement (Part 3) arranged on the second key. Here, resistance to change was greater for the component with greater overall reinforcement. Failures of momentum theory to predict short-term differences in resistance to change occurred with disruptors that caused greater change between steady states for the richer component. Consistency of effects across disruptors may yet be found if short-term effects of disruptors are assessed relative to the extent of change observed after prolonged exposure.  相似文献   
202.
临床经验对诊断的双重作用及改造   总被引:1,自引:0,他引:1  
文中用辩证唯物主义的观点,阐述了临床经验的定义、来源及指导实践过程中的意义,指出其具有促进诊断和引起误诊的双重作用,并用临床病历例子详细说明其双重作用的形式、导致结果及产生的原因。指出临床经验的双重作用在临床工作中的重要性及局限性,提出对经验的改造完善途径,以能充分表现出其促进诊断的作用,而最大限度降低其导致误诊的程度,发挥在临床工作中的良性作用。  相似文献   
203.
Four homing pigeons were trained over 5 months in a zero-delay, “arbitrary” matching-to-sample procedure with sample and comparison stimuli presented on any of three response keys. Birds were also required to complete a fixed-ratio 10 requirement on both sample and comparison stimuli to terminate their presentation. The procedure resulted in the establishment of relations that were not specifically trained and that can be characterized by the property of transitivity in a stimulus equivalence context. This result was in contrast with the findings obtained from most previous research with nonhuman subjects.  相似文献   
204.
ObjectivesThe Integrated Model of Flow and Clutch States describes two overlapping psychological states that underlie exceptional performance and rewarding exercise experiences. However, research based on this model is currently hampered because no validated measure has yet been developed. Therefore, the aim of this multi-study paper was to develop and provide preliminary validation of the Flow-Clutch Scale in sport and exercise.DesignUsing two independent adult samples (n = 280; n = 264), three studies were conducted to develop and establish preliminary validity of the Flow-Clutch Scale.MethodIn Study 1, we developed an initial version of the scale and established content validity using an expert panel. In Study 2, we employed exploratory factor analysis to: identify the most appropriate factor structure; examine the scale’s internal consistency; test whether the scale differentiated between individuals who experience flow, clutch, or neither state; and examine relationships with the Flow State Scale-2. In Study 3, we aimed to replicate findings of Study 2 with an independent sample, and employed confirmatory factor analysis to confirm the factor structure, internal consistency, and relationships with the Flow State Scale-2.ResultsThe results provide preliminary validation of the four-factor, 22-item Flow-Clutch Scale.ConclusionsThese studies indicate the Flow-Clutch Scale represents a useful scale for researchers interested in examining flow and/or clutch states in sport and exercise. Recommendations are provided for further research to continue testing, and accumulating evidence for, the validity and reliability of the Flow-Clutch Scale.  相似文献   
205.
Pigeons responded on two keys in each component of a multiple concurrent schedule. In one series of conditions the distribution of reinforcers between keys within one component was varied so as to produce changes in ratios of reinforcer totals for key locations when summed across components. In a second series, reinforcer allocation between components was varied so as to produce changes in ratios of reinforcer totals for components, summed across key locations. In each condition, resistance to change was assessed by presenting response-independent reinforcers during intercomponent blackouts and (for the first series) by extinction of responding on both keys in both components. Resistance to change for response totals within a component was always greater for the component with the larger total reinforcer rate. However, resistance to change for response totals at a key location was not a positive function of total reinforcement for pecking that key; indeed, relative resistance to extinction for the two locations showed a weak negative relation to ratios of reinforcer totals for key location. These results confirm the determination of resistance to change by stimulus—reinforcer contingencies.  相似文献   
206.
Eight pigeons were trained on a delayed presence-versus-absence discrimination paradigm in which a sample stimulus was presented on some trials but not on others. If a sample was presented, then a response to one choice key produced food. If no sample was presented, a response to the other choice key produced food. The basic finding was that performance remained constant and well above 50% correct on no-sample trials as the retention interval increased, whereas performance dropped precipitously (to below 50% correct) on sample trials. In the second phase of the experiment, all of the trials were no-sample trials, and reinforcers were delivered probabilistically for one group of pigeons and according to time-based schedules for the other group. The exact reinforcement probabilities used in Phase 2 were those calculated to be in effect on no-sample trials in Phase 1 (according to a discrete-state model of performance). Subjects did not show exclusive preference for the richer alternative on no-sample trials in the first phase, but those in the probabilistic group developed near-exclusive preference for the richer alternative during the second phase. These data are inconsistent with the predictions of the discrete-state model, but are easily accommodated by an account based on signal detection theory, which also can be applied effectively to discrimination of event duration and the “subjective shortening” effect.  相似文献   
207.
7-15岁儿童对友谊关系的认知及其发展   总被引:1,自引:0,他引:1  
用以承诺为主题的两难推理故事探查7-15岁儿童对友谊关系的认知及其发展。结果表明,儿童的有关发展制约于社会观点采择能力的发展和调节友谊关系的道德规范的理解,并表现出阶段结构的发展模式,我国儿童的发展具有某种跨文化的普遍性,也显示出自己的特点。  相似文献   
208.
考察了结果预期与结果反应对儿童意图认知和道德判断的影响。结果表明,结果预期影响幼儿园和小学儿童的意图认知,结果反应仅影响幼儿园儿童的意图认知;结果预期和结果反应显著地影响幼儿园和小学儿童的道德判断,但结果预期对小学儿童道德判断的影响要比结果反应大。  相似文献   
209.
Starting with a prototypical model of Newtonian mechanics, a sequence of dynamic models with increasing structural complexity is presented. The implicated smooth variation along a dimension of structural complexity yields dynamic models which display organismic properties such as stagewise development and emergent self-organization. Consequently, it is concluded that dynamic models of development are inherently neutral with respect to the mechanism-organicism controversy. Accordingly, a unitary research program is proposed in which these dynamic models serve as building blocks for the construction of a coherent explanatory system of development.  相似文献   
210.
One of Dennett's principal arguments for an instrumentalistic construal of intentional attributions (e.g., attributions of belief, etc.) is that such attributions are environment relative. I argue that one can and should adopt a realist perspective toward such attributions, but accommodate their environmental relativity by treating intentional properties as relational properties. By doing so one acquires a useful perspective on experimental cognitive psychology; in particular, one can overcome the temptation to treat ecological accounts and information processing accounts as incompatible alternatives and come to see them as mutually supportive. Treating intentional properties as relational may be counter-intuitive, but I provide examples of how other sciences have had to treat what seem to be intrinsic properties as relational.  相似文献   
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