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81.
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   
82.
This article attempts to analyse the ongoing debate regarding open-mindedness as an educational value. The views of Hare, McLaughlin and Gardner are considered. They do not always agree on what open-mindedness is, and the discussion could benefit from a more unified terminology and better counter-examples. The value and limitations of open-mindedness in both science and the humanities are discussed and analysed. It is argued that open-mindedness, while clearly a virtue if not taken to excess, need not be a goal of the educational process.  相似文献   
83.
Instruction in hematopathology at Mayo Medical School has evolved from instructor‐guided direct inspection under the light microscope (laboratory method), to photomicrographs of glass slides with classroom projection (projection method). These methods have not been compared directly to date. Forty‐one second‐year medical students participated in this pilot study, a prospective, randomized, crossover study measuring educational performance during a hematology pathophysiology course. The students were randomized to one of two groups. All students received the same didactic lectures in the classroom and subsequent case‐based review of peripheral blood smears using either laboratory or projection methods, on day one with a crossover to the other method on day two. Pre‐ and post‐test examinations centered on morphology recognition measured educational performance on each day, followed by a questionnaire identifying the student's favored method. There was no significant difference in the pre‐test and post‐test scores between the two teaching methods (rank‐sum P = 0.43). Students overwhelmingly preferred the projection method and perceived it as superior (76%), although post‐test scores were not significantly different. Student's recommended method was split with 50% favoring the projection method, 43% favoring a combined approach, and 23% noting logistical challenges to the laboratory. In this study, the laboratory and projection method were equivalent in terms of educational performance for hematopathology among medicals students. A classroom‐based approach such as the projection method is favored, given the large class sizes in undergraduate medical education, as well as the ergonomic challenges and additional resources required for large group instruction in a laboratory setting. Anat Sci Educ 7: 130–134. © 2013 American Association of Anatomists.  相似文献   
84.
This study investigated whether humans have two mind‐reading systems whereby the efficient system, unlike the flexible system, is naturally limited. There were two experiments and the first included adults as well as children (3‐ to 4‐year‐olds; total = 128). In Experiment 1, all groups efficiently gazed in anticipation of an agent's beliefs about object location but not object identity (an ambiguous figure). In Experiment 2, children showed limits in anticipating a competitive agent's action in terms of his perspective on what is desirable. Flexibility in verbally predicting agents' actions across contexts developed with age. Convergence on signature limits across different ages and methods suggests that indirect anticipations involve minimal mind reading, whereas direct predictions tap a refined understanding of perspective.  相似文献   
85.
Given the crucial role of suppliers in collaborative supply chains, it is surprising that little attention has been paid to the nature and management of supplier relationships in the implementation of a retailer's Customer Relationship Management (CRM) strategy. To address this gap in the extant literature, the theory of organizational justice is used to explore the extent to which perceived fairness in buyer–supplier relationships supports or inhibits supplier engagement with the CRM process. The rationale is that suppliers who feel fairly treated by key retail customers are more likely to invest resources in the acquisition and use of data central to the retailer's CRM strategy. By empirically testing a conceptual model linking downstream CRM to upstream SRM, the results provide evidence to indicate that customer data use is significantly influenced by perceptions of fairness, particularly with respect to the distribution of rewards, and the transparency of decision-making processes. As a key criticism of CRM centers upon the failure of organizations to exploit the full potential of customer data, the results highlight the usefulness of understanding the relational linkages between buyers and suppliers and the consequential behavior of suppliers in terms of engagement with customer data vital to the success of retailers’ CRM strategies.  相似文献   
86.
By and large, we think (Strevens's [2005]) is a useful replyto our original critique (Fitelson and Waterman [2005]) of hisarticle on the Quine–Duhem (QD) problem (Strevens [2001]).But, we remain unsatisfied with several aspects of his reply(and his original article). Ultimately, we do not think he properlyaddresses our most important worries. In this brief rejoinder,we explain our remaining worries, and we issue a revised challengefor Strevens's approach to QD.
1 Strevens's ‘clarifications’
2 Strevens's new-and-improved ‘negligibility arguments’
  相似文献   
87.
Isolation and enrichment of low-abundant particles are essential steps in many bio-analytical and clinical applications. In this work, the capability of an insulator-based dielectrophoresis (iDEP) device for the detection and stable capture of low abundant polystyrene particles and yeast cells was evaluated. Binary and tertiary mixtures of particles and cells were tested, where the low-abundant particles had concentration ratios on the order of 1:10 000 000 compared to the other particles present in the mixture. The results demonstrated successful and stable capture and enrichment of rare particles and cells (trapping efficiencies over 99%), where particles remained trapped in a stable manner for up to 4 min. A device with four reservoirs was employed for the separation and enrichment of rare particles, where the particles of interest were first selectively concentrated and then effectively directed to a side port for future collection and analysis. The present study demonstrates that simple iDEP devices have appropriate screening capacity and can be used for handling samples containing rare particles; achieving both enrichment and isolation of low-abundant particles and cells.  相似文献   
88.
Given the high prevalence of HIV/AIDS in Kenya, more Kenyans now find themselves in the role of informal caregiver for a family member or multiple family members living with HIV/AIDS. However, there exists little research on how these individuals cope. The present study explores coping responses among caregivers for family members living with HIV/AIDS in Kenya. An exploratory factor analysis of the Brief COPE yielded five factors, with strong loadings on Emotional Support and Instrumental Support. Implications for using the Brief COPE in research and clinical practice among Kenyans are discussed.  相似文献   
89.
Elementary and special education teachers and school counsellors currently provide support to children presenting learning disabilities and behavioural problems symptomatic of the more hidden diagnosis of complex trauma resulting from abuse or severe attachment disruption. Specific disorders such as attention deficit/hyperactivity disorder (AD/HD) may be diagnosed in such children, but not the aetiology of complex trauma, resulting in missing information in the development of remedial and behavioural interventions. The evolving field of trauma counselling provides important information to special education teachers and school counsellors who work with children who have experienced trauma. In this review article authors Linda O'Neill of the University of Northern British Columbia (UNBC), Francis Guenette who is a doctoral student at the University of Victoria and Andrew Kitchenham of the University of Northern British Columbia summarise attachment, neurobiological, and complex trauma research that can be used in school settings to understand better the needs of these children. They conclude by suggesting that teachers and school counsellors would benefit from training on the consequences of childhood trauma and attachment disruption to develop interventions that will be effective and to identify what types of behaviours children can control and those they cannot.  相似文献   
90.
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