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991.
992.
Weekes  B.S.  Chen  M.J.  Lin  Y-B. 《Reading and writing》1998,10(3-5):201-221
We report two experiments investigating the effect of phonological priming on the recognition of two types of Chinese characters: compound targets which contain separate radical components; and integrated targets which do not contain separate radicals. We used a masked priming paradigm with varying prime-target exposure durations. In Experiment 1, phonological priming effects on compound target recognition were found following a 50 msec SOA. However, there was no evidence of phonological priming on integrated target recognition at this SOA. In Experiment 2 we investigated the time course of phonological priming effects at three prime-target SOAs (30, 50 and 80 msec) in a between-subjects design. Semantic priming effects were also investigated. Phonological priming effects on compound target recognition were found following the 50 msec and the 80 msec SOAs. However, there was no evidence of phonological priming on integrated target recognition at any SOA. Semantic priming effects on both compound and integrated target recognition were found in the 50 msec and the 80 msec SOA conditions suggesting that phonological and semantic activation are co-incidental during compound character recognition. We conclude that character type constrains the activation of phonology during Chinese character recognition.  相似文献   
993.
Critical thinking and skills in defining problems have been among the goals of a computers and society course that had its credits reduced and student number increased. In an attempt to prevent worsening the students' learning, four measures were taken. The results actually improved from a failure rate of 21.5% to 0.7%. This was mainly due to tighter project structure and additional student work. Reduced course material and improved teacher preparation did not seem to have any effect, while more focused project teaching may have contributed to the decreased failure rate. Further improvements may be gained through time estimation in the problem definition process.  相似文献   
994.
995.
996.
The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the mole concept in high school and introductory college chemistry textbooks. The analysis was framed by four questions:
  • 1 How is the mole defined?
  • 2 What concepts about the atom are introduced prior to the mole?
  • 3 Is Avogadro's constant presented as an experimentally determined value?
  • 4 What is the context for introducing the mole?
Twenty-nine high school and introductory college level chemistry texts were examined. After independent reading of appropriate sections of each text, discussion of differences, second or third readings of texts, and subsequent discussions, both authors reach 100% agreement concerning the results. Major conclusions were
  • 1 Two ways of defining the mole dominate the texts. One way defines the mole as Avogadro's number (6.02 × 1023) particles; the other method defines the mole in terms of carbon-12.
  • 2 All texts that present a definition in terms of C-12 introduce and define concepts about the atom prior to introducing the mole.
  • 3 Most texts at all levels point out that the value 6.02 × 1023 is an experimentally determined quantity.
  • 4 Nearly all texts discuss the mole in relation to die problem of finding a way to count particles that are too small to be directly weighed. Most texts also use a familiar counting unit, such as the dozen, to introduce the mole by analogy.
Four issues were discussed: (a) the defining attributes of the mole concept itself and the cognitive requirements for comprehending the two most frequently used definitions; (b) the connection between the definition of the mole presented in the text and the concepts about atoms that are introduced before the mole concept is developed; (c) the experimental nature of Avogadro's number; and (d) the context or setting for developing the mole concept.  相似文献   
997.
Weanling rats were tested for retention of an aversion to a novel flavor (chocolate milk) that had been conditioned as a single-element conditioned stimulus (CS) or in compound with a novel ambient odor (banana). The presence of the ambient odor during conditioning had no effect on flavor aversion shortly thereafter, confirming previous results. The flavor aversion observed 21 days after conditioning, however, was significantly stronger for pups conditioned with the single-element CS than for those given the flavor-odor compound as the CS. This retention effect was due to a surprisingincrease in the conditioned aversion observed 21 days after conditioning with the single-element CS. A second experiment confirmed this paradoxical increase in retention of the aversion to chocolate milk. This experiment also verified that no such increase occurred in retention of the conditioned aversion to a different flavor (saccharin), whether the initial aversion was strong or weak. The results may be explained in terms of generalized latent inhibition from consumption of mother’s milk.  相似文献   
998.
Pigeons were trained to match-to-sample with several new methodologies: a large number of stimuli, computer-drawn color picture stimuli, responses monitored by a computer touch screen, stimuli presented horizontally from the floor, and grain reinforcement delivered onto the picture stimuli. Following acquisition, matching-to-sample concept learning was assessed by transfer to novel stimuli on the first exposure to pairs of novel stimuli. One group (trial-unique), trained with 152 different pictures presented once daily, showed excellent transfer (80% correct). Transfer and baseline performances were equivalent, indicating that the matching-to-sample concept had been learned. A second group (2-stimulus), trained with only two different pictures, showed no evidence of transfer. These results are discussed in terms of the effect of numbers of exemplars on previous failures to find concept learning in pigeons, and the implications of the positive finding from this experiment on abstract concept learning and evolutionary cognitive development.  相似文献   
999.
The first part of the article provides a historical account of the broad phases of development that educational television has passed through as a result of social and technological influences:
  • its beginnings in broadcasting in the fifties and sixties;

  • its development through the video age in the seventies and eighties, with widening scope and opportunity as a result of developments in production and reception/recording equipment and an expansion of communication channels;

  • its present potential, at the dawn of the interactive age, as a result of the influences of new technology.

The article then examines the problems of integrating new television‐related technologies into the educational system and draws attention to:

  • the frequent past failures of the educational system to fully exploit new technologies, resulting in superficial integration and ineffectual use;

  • the current tensions between the traditional educational technology approach and the drives behind much new technology;

  • the need for appropriate systems and structures to ensure that the evaluation of such new technologies is properly resourced and effectively carried out.

  相似文献   
1000.
There is much interest in science courses in high school and student attitudes toward those courses. A valid and reliable instrument that measures such attitudes is not available. This study first developed and validated the Attitude toward Science in School Assessment (ATSSA). The instrument was used to evaluate the relationship between such attitude and achievement in science. A low correlation was found between attitude and various achievement tests. A moderate correlation was found between attitude and achievement that included an evaluation of the quality of work, as in a course grade.  相似文献   
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