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241.
The basis of having a direct moral obligation to an entity is that what we do to that entity matters to it. The ability to experience pain is a sufficient condition for a being to be morally considerable. But the ability to feel pain is not a necessary condition for moral considerability. Organisms could have possibly evolved so as to be motivated to flee danger or injury or to eat or drink not by pain, but by “pangs of pleasure” that increase as one fills the relevant need or escapes the harm. In such a world, “mattering” would be positive, not negative, but would still be based in sentience and awareness. In our world, however, the “mattering” necessary to survival is negative—injuries and unfulfilled needs ramify in pain. But physical pain is by no means the only morally relevant mattering—fear, anxiety, loneliness, grief, certainly do not equate to varieties of physical pain, but are surely forms of “mattering.” An adequate morality towards animals would include a full range of possible matterings unique to each kind of animal, what I, following Aristotle, call “telos”. Sometimes not meeting other aspects of animal nature matter more to the animal than does physical pain. “Negative mattering” means all actions or events that harm animals—from frightening an animal to removing its young unnaturally early, to keeping it so it is unable to move or socialize. Physical pain is perhaps the paradigmatic case of “negative mattering”, but only constitutes a small part of what the concept covers. “Positive mattering” would of course encompass all states that are positive for the animal. An adequate ethic for animals takes cognizance of both kinds. The question arises as to how animals value death as compared with pain. Human cognition is such that it can value long-term future goals and endure short-run negative experiences for the sake of achieving them. In the case of animals, however, there is no evidence, either empirical or conceptual, that they have the capability to weigh future benefits or possibilities against current misery. We have no reason to believe that an animal can grasp the notion of extended life, let alone choose to trade current suffering for it. Pain may well be worse for animals than for humans, as they cannot rationalize its acceptance by appeal to future life without pain. How can we know that animals experience all or any of the negative or positive states we have enumerated above? The notion that we needed to be agnostic or downright atheistic about animal mentation, including pain, because we could not verify it through experience, became a mainstay of what I have called “scientific ideology”, the uncriticized dogma taught to young scientists through most of the 20th century despite its patent ignoring of Darwinian phylogenetic continuity. Together with the equally pernicious notion that science is “value-free”, and thus has no truck with ethics, this provided the complete justification for hurting animals in science without providing any pain control. This ideology could only be overthrown by federal law. Ordinary common sense throughout history, in contradistinction to scientific ideology, never denied that animals felt pain. Where, then, does the denial of pain and other forms of mattering come from if it is inimical to common sense? It came from the creation of philosophical systems hostile to common sense and salubrious to a scientific, non-commonsensical world view. Reasons for rejecting this philosophical position are detailed. In the end, then, there are no sound reasons for rejecting knowledge of animal pain and other forms of both negative and positive mattering in animals. Once that hurdle is cleared, science must work assiduously to classify, understand, and mitigate all instances of negative mattering occasioned in animals by human use, as well as to understand and maximize all modes of positive mattering.  相似文献   
242.
The purpose of this study was to evaluate the effect the visual fidelity of a virtual environment (VE) (undetailed vs. detailed) has on the transfer of spatial knowledge based on the navigation mode (passive vs. active) for three different spatial recall tasks (wayfinding, sketch mapping, and picture sorting). Sixty-four subjects (32 men and 32 women) participated in the experiment. Spatial learning was evaluated by these three tasks in the context of the Bordeaux district. In the wayfinding task, the results indicated that the detailed VE helped subjects to transfer their spatial knowledge from the VE to the real world, irrespective of the navigation mode. In the sketch-mapping task, the detailed VE increased performances compared to the undetailed VE condition, and allowed subjects to benefit from the active navigation. In the sorting task, performances were better in the detailed VE; however, in the undetailed version of the VE, active learning either did not help the subjects or it even deteriorated their performances. These results are discussed in terms of appropriate perceptive-motor and/or spatial representations for each spatial recall task.  相似文献   
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The study identified independent individual, family, and neighborhood correlates of children's physical aggression and prosocial behavior. Participants were 2,745 2–11-year olds nested in 1,982 families, which were themselves nested in 96 Canadian neighborhoods. Hierarchical linear modeling showed that the total variation explained by the three-level model was 28.03% for physical aggression and 17.57% for prosocial behavior. For both childhood behaviors, approximately 66% of this explained variance was between individuals and up to 30% was between families. The smallest amount of observed variation was between neighborhoods. Significant individual-level predictors common to both childhood behaviors were child's sex and maternal hostility toward the target child. Specifically, boys had more mother-reported physical aggression and less prosocial behavior. Children who experienced greater-than-average maternal hostility (compared to siblings) were more physically aggressive and less prosocial. At the family level, significant common predictors were mother depressed mood and punitive parenting. Children had higher levels of physical aggression and lower levels of prosocial behavior in families where mothers had greater depressed mood and used more punitive parenting practices. At the neighborhood level, greater perceived problems and lower poverty level were associated with higher levels of physical aggression. Results are discussed with reference to past and future studies of multilevel effects on children's socialization.  相似文献   
246.
Patients with Parkinson's disease (PD) exhibit deficits in perceptual and motor timing as well as impairments in memory and attentional processes that are related to dysfunction of dopaminergic systems in the basal ganglia. The aim of the present study was to assess the relationships existing between impaired duration judgments and defective memory and attention in PD patients. We compared time performance of medicated PD patients and control subjects on a duration reproduction task that is highly memory-dependent, and on a duration production task that could reveal effects of changes in the speed of internal time-keeping mechanisms. Each task was performed in a control counting condition and in a condition requiring divided attention between the temporal task and a concurrent reading task. Moreover, PD patients and control subjects were assessed on memory and attention using a battery of neuropsychological tests. The results revealed that in the concurrent reading condition of the reproduction task, duration judgments tended to be more variable in PD patients than in control subjects. Moreover, variability of duration reproductions was correlated with both measures of memory and of disease severity. In the concurrent reading condition of the production task, duration judgments were significantly shorter in PD patients than in control subjects, and accuracy of duration productions was correlated with scores on sub-tests of short-term memory. The findings suggest that the administration of dopamine did not entirely remove the memory deficits in PD patients. Moreover, DA treatment would have abnormally accelerated the rate of the internal clock leading to shorter duration productions in PD patients. The whole results indicate that dopamine administration in patients might have overshadowed the slowing rate of the internal clock usually reported in non medicated PD patients, without entirely restoring all of the memory functions.  相似文献   
247.
Recent data indicate that the familiarity and the emotional expression of faces occur at an early stage of information processing. The goal of the present study was to determine whether these two aspects interact at the structural encoding stage as reflected by the N170 component of event-related potentials in tasks requiring the subjects either to identify whether the faces were familiar or the nature of the emotional expression. The results indicate that the neural responses to level of familiarity and emotional expression were observable at this early processing stage but without interacting. In particular, faces of personal importance to the subjects differed from those of less personal importance. Because familiarity did not interact with emotional expression at behavioral and electrophysiologic levels, our results support the contention of parallel and independent processing of faces.  相似文献   
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Two experiments examined the motivational specificity of the associations that support 2nd-order conditioning. In the 1st phase of each experiment rats were exposed to 2 visual conditioned stimuli (CSs) paired with either a saline or food pellet unconditioned stimulus (US) prior to exposure to 2nd-order conditioning using 2 auditory CSs, 1 paired with each visual CS. Rats' motivational state was then shifted prior to a test such that if and only if specific motivational features of the 1st-order training US played a role in the 2nd-order associative structure would responding to the 2nd-order cues shift appropriately with the state change. Even when the US was irrelevant to the training motivational state, shifts in state revealed that it was encoded within the associative structure supporting 2nd-order responding.  相似文献   
250.
Forward and backward blocking of taste preference learning was compared in rats. In the forward condition, thirsty rats were exposed to a flavor (A) in sucrose solution (+) or in water (-), after which they were exposed to A in compound with another flavor (B) in sucrose solution (i.e., AB+). In the backward condition, these phases were reversed. Consumption of B alone was assessed when rats were food deprived. In the forward condition, rats given A+ consumed less B than rats given A-, providing evidence of forward blocking, whereas in the backward condition, rats given A+ drank more of B than those given A-. Subsequent experiments found that alternating but not blocked preexposure to A and B, when given prior to training, produced blocking of B whether A+ was given before or after AB+, suggesting that prior failures to observe backward blocking reflect failures of discrimination.  相似文献   
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