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941.
942.
This study investigated differences in depressed and nondepressed children's recall of positively and negatively reinforced behavior. Twenty-six children with self-reported symptoms of depression in the fourth through sixth grades were compared with a matched sample of 26 nondepressed children to determine if there was a negative bias in depressed children's recall. Subjects first generated guesses of the most common associations to each of a series of 40 words. Later, when compared with their nondepressed peers, the children with depressive symptomology were less accurate in recalling which words they had answered correctly and remembered fewer of their own correct responses. They also did more poorly when asked to recall the correct answers that had been provided by the investigator. The two groups did not differ, however, in their recall of which items had been answered incorrectly or in their recall of their previous wrong responses. These results suggest that children with self-reported depressive symptomology do not remember negative experiences more than do nondepressed children; rather, they recall positive experiences less well. Selective forgetting of positively reinforced behavior could be a serious handicap for depressed children in school. It could also play an important role in the maintenance and perhaps even the etiology of depressive symptomatology in children.We wish to thank Bruce Compas for his helpful comments on an earlier draft of this paper.  相似文献   
943.
The short- and long-range apparent motion processes are discussed in terms of the statistical properties of images. It is argued that the short-range process, exemplified by the random-dot kinematogram, is primarily sensitive to the dipole statistics, whereas the long-range process, exemplified by illusory occlusion, is treated by the visual system primarily in terms of the tripole and higher statistical correlation functions. The studies incorporate the balanced dot, which is a unique stimulus element that permits high pass filtering while preserving detailed positional information. Low spatial frequencies are shown to be critical for texture segregation in random-dot kinematograms, independent of the grain size or number density of texture elements. Illusory path perception in the long-range process is shown not to require low spatial frequencies, but is sensitive rather to global temporal phase coherency. These results are interpreted in terms of the respective roles of the power and phase spectra in perceptual organization. The construction of balanced dots is discussed in detail.  相似文献   
944.
The FACTRETRIEVAL2 test battery, which assesses both retrieval of general information from memory and metacognition about that retrieval, was administered to people before and after a recent expedition to Mount Everest and at extreme altitudes above 6,400 m (higher than any mountain in North America or Europe). The major findings were as follows: First, the same extreme altitudes already known to impair learning did not affect either accuracy or latency of retrieval, and this robustness of retrieval occurred for both recall and forced-choice recognition. Second, extreme altitude did affect metacognition: The climbers showed a decline in their feeling of knowing both while at extreme altitude and after returning to Kathmandu (i.e., both an effect and an aftereffect of extreme altitude). Third, extreme altitude had different effects than alcohol intoxication (previously assessed by Nelson. McSpadden, Fromme, & Marlatt, 1986). Alcohol intoxication affected retrieval without affecting metacognition, whereas extreme altitude affected metacognition without affecting retrieval; this different pattern for extreme altitude versus alcohol intoxication implies that (a) hypoxia does not always yield the same outcome as alcohol intoxication and (b) neither retrieval nor metacognition is strictly more sensitive than the other for detecting changes in independent variables.  相似文献   
945.
We present a study wherein a severe Broca's aphasic patient was trained to learn symbols representing both pure transitive and dative predicates--predicates differing in argument structure--in a visually based artificial language (c-ViC). We found a decrease in performance when two symbols, rather than one, were used to depict these "verbs." However, this decrease in performance was more pronounced for symbols representing pure transitive verbs--those that allow only one argument structure--than for symbols representing dative verbs--those that allow two different argument structures. Also, dative "verbs" yielded better performance when they were inserted in more complex, three-argument "sentences" than when they were inserted in two-argument "sentences." The opposite pattern was found for pure transitives. These results are discussed in terms of our claim that argument structure serves as a point of connection between linguistic information and non-linguistic visual information and in terms of the possibility that argument structure entries are shaped by the form in which visual information is parsed.  相似文献   
946.
Sperling, Landy, Dosher, and Perkins (1989) proposed an objective 3D shape identification task with 2D artifactual cues removed and with full feedback (FB) to the subjects to measure KDE and to circumvent algorithmically equivalent KDE-alternative computations and artifactual non-KDE processing. (1) The 2D velocity flow-field was necessary and sufficient for true KDE. (2) Only the first-order (Fourier-based) perceptual motion system could solve our task because the second-order (rectifying) system could not simultaneously process more than two locations. (3) To ensure first-order motion processing, KDE tasks must require simultaneous processing at more than two locations. (4) Practice with FB is essential to measure ultimate capacity (aptitude) and, thereby, to enable comparisons with ideal observers. Experiments without FB measure ecological achievement--the ability of subjects to extrapolate their past experience to the current stimuli.  相似文献   
947.
The sociobiological version of human evolution is criticized as excessively reductionistic and focused on reproductive competition. An alternative version of evolutionary psychology is proposed based on the premise that the most important feature of human evolutionary history is selection for small group living. The structural requirements of group survival can account for fundamentally social motives characteristic of the human species such as cooperation, conformity, and group loyalty.Adapted from a symposium presentation at the annual meeting of the Society for Experimental Social Psychology, October 13, 1990, Buffalo, New York.  相似文献   
948.
Rule abstraction, item memory, and chunking in rat serial-pattern tracking   总被引:1,自引:0,他引:1  
Two studies used a stimulus tracking paradigm to test whether rats are sensitive to the rule-based formal properties of structured serial patterns. Hooded rats tracked 16-element patterns of flashing lights by pressing levers under an array of 6 indicator lights. In Experiment 1, rats tracked a pattern similar to one previously used with human subjects and yielded remarkably similar results. More errors and response omissions occurred at boundaries of structural "chunks" than within chunks, and errors often reflected anticipation of the next chunk or extrapolation of the preceding chunk. In Experiment 2, temporal "phrasing" cues encouraged different groups to encode a pattern as a series of either "runs" or "trills." Differential placement of pauses induced rats to encode different rule-based representations of the pattern. Results indicate that under appropriate conditions rats may encode a representation of formal structure when they learn organized response patterns.  相似文献   
949.
Ellis's neurohormonal theory of criminality is briefly reviewed, and its relevance for understanding suicidal behavior is explored. It was found that many variables identified by Ellis as characteristic of criminals are also characteristic of suicidal individuals. In addition, Ellis's perspective identified many issues that have been explored only cursorily or not at all by suicidologists. Ellis's theory may, therefore, have heuristic value for suicidology.  相似文献   
950.
Women and AIDS     
While the origin of the AIDS virus remains controversial, it is indisputable that AIDS is spreading worldwide. By June 1987, the World Health Organization estimated that 50 million Africans were infected with HIV and that the disease was epidemic in many parts of the continent. However, African governments chose to deny the threat of the disease. The AIDS crisis has diverted resources from other vital areas of disease prevention, health promotion, and research. Whereas AIDS is spread in developed nations by sexual promiscuity, by drug addicts sharing unclean hypodermic needles, and by homosexual behavior, in Africa cultural factors contribute to the transmission of AIDS. Female genital mutilation leads to extensive laceration of the female genitals upon initiation of sexual intercourse and/or to substitution of anal sex during the weeks and months before vaginal penetration can be achieved. In addition, the reuse of the same knives during the mutilation can spread HIV infection. Other factors that contribute to the spread of HIV in Africa include the patriarchal practice of polygamy, the subordinate position of women that makes them unable to insist on protection during intercourse, and a failure to screen blood used in transfusions. With all of these risk factors at play, women at the grassroots level must be equipped with the health education that is the only available tool to fight AIDS. Women's organizations can provide information and education to people at risk of acquiring HIV, counsel infected persons, ensure the safety of the blood supply, and work to overcome harmful traditional practices.  相似文献   
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