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This study investigated the knowledge gains and attitude shifts attributable to a unique online science education game, Uncommon Scents. The game was developed to teach middle school students about the biological consequences of exposure to toxic chemicals in an environmental science context, as well as the risks associated with abusing these chemicals as inhalants. Middle school students (n = 444) grades six through eight participated in the study consisting of a pre-test, three game-play sessions, and a delayed post-test. After playing the game, students demonstrated significant gains in science content knowledge, with game usability ratings emerging as the strongest predictor of post-test content knowledge scores. The intervention also resulted in a shift to more negative attitudes toward inhalants, with the most negative shift occurring among eighth grade students and post-test knowledge gains as the strongest predictor of attitude change across all grade levels. These findings suggest that the environmental science approach used in Uncommon Scents is an efficacious strategy for delivering both basic science content and influencing perceived harm relating to the inhalation of toxic chemicals from common household products.  相似文献   
164.
Humans discount larger amounts of a delayed reinforcer less steeply than smaller amounts, but studies with pigeons and rats have yet to reveal such a magnitude effect, suggesting that the effect may be unique to humans. The present study examined whether the magnitude effect is observed in a species phylogenetically closer to humans, by comparing the rates at which rhesus monkeys discounted 10% and 20% concentrations of sucrose. There were no systematic differences in the rates at which the monkeys discounted the two sucrose concentrations, despite the fact that they strongly preferred the 20% concentration. Interestingly, the monkeys discounted delayed sucrose at a rate higher than was observed with delayed cocaine, and lower than was observed with delayed saccharin in previous studies (Freeman et al. Behavioural Processes, 82, 214-218, 2009; Woolverton et al. Experimental and Clinical Psychopharmacology, 15, 238-244, 2007). Taken together, these findings suggest that although both quantitative and qualitative differences can affect monkeys’ preferences between immediate reinforcers, qualitative differences between types of reinforcers (e.g., sucrose vs. cocaine) can affect monkeys’ discounting rates in a way that quantitative differences within a reinforcer (e.g., 10% vs. 20% sucrose) do not.  相似文献   
165.
Recent advances in miniaturized waterproof accelerometers have allowed their use as a tool in examining swim stroke characteristics (Ohgi et al. JPSE Int J 45:960–966, 2002; Sports Eng 6:113–123, 2003). A better use for this technology, however, might be to quantify characteristics of competitive swim training. The purpose of this study was thus to examine commercial accelerometers’ ability to track and quantify swim training variables common to all swim training programs: speed and distance. Swimmers (n = 43) were fitted with two accelerometer monitors on their right wrist and ankle. From this output, regression analyses were performed as a means to describe swim distance and speed. Ten additional swimmers (experimental group, n = 10) were then utilized to cross validate these equations as being useful to predict swim distance and speed. The results demonstrated a positive, significant relationship between activity counts and actual swim distance (r = 0.90, p < 0.05), actual swim speed (r = 0.80; p < 0.05), and cross validation confirmed the accuracy of the prediction equations. The findings of the present study suggest that commercial accelerometer-based activity monitors have the ability to quantify important characteristics of competitive swim training.  相似文献   
166.
Abstract

To determine whether respiratory muscle strength is related to pulmonary volume differences in athletes and nonathletes, 11 intercollegiate female swimmers, 11 female cross-country runners, and two nonathletic control groups, matched to the athletes in height and age, were evaluated for pulmonary parameters including maximal inspiratory pressure (Plmax) and maximal expiratory pressure (PEmax). Swimmers exhibited larger (p < .05) vital capacities (VC), residual lung volumes (RV), inspiratory capacities (IC), and functional residual capacities (FRC) than both the runners or the controls but no difference (p > .05) in either Plmax or inspiratory flow (FIV25%-75%). Timed expiratory volumes (FEV Q.5 m and FEV1.0 were significantly (p < .05) lower in the swimmers than in the controls. These data suggest that an adaptational growth may be responsible, in part, for the augmented static lung volumes demonstrated in swimmers  相似文献   
167.
We report on the development of an item test bank and associated instruments based on the National Research Council (NRC) K–8 life sciences content standards. Utilizing hundreds of studies in the science education research literature on student misconceptions, we constructed 476 unique multiple-choice items that measure the degree to which test takers hold either a misconception or an accepted scientific view. Tested nationally with 30,594 students, following their study of life science, and their 353 teachers, these items reveal a range of interesting results, particularly student difficulties in mastering the NRC standards. Teachers also answered test items and demonstrated a high level of subject matter knowledge reflecting the standards of the grade level at which they teach, but exhibiting few misconceptions of their own. In addition, teachers predicted the difficulty of each item for their students and which of the wrong answers would be the most popular. Teachers were found to generally overestimate their own students performance and to have a high level of awareness of the particular misconceptions that their students hold on the K–4 standards, but a low level of awareness of misconceptions related to the 5–8 standards.  相似文献   
168.
Drawn from the norms and rules of their fields, scientists use variety of practices, such as asking questions and arguing based on evidence, to engage in research that will contribute to our understanding of Earth and beyond. In this study, we explore how preservice teachers' learn to teach scientific practices while teaching plate tectonic theory. In particular, our aim is to observe which scientific practices preservice teachers use while teaching an earth science unit, how do they integrate these practices into their lessons, and what challenges do they face during their first time teaching of an earth science content area integrated with scientific practices. The study is designed as a qualitative, exploratory case study of seven preservice teachers while they were learning to teach plate tectonic theory to a group of middle school students. The data were driven from the video records and artifacts of the preservice teachers' learning and teaching processes as well as written reflections on the teaching. Intertextual discourse analysis was used to understand what scientific practices preservice teachers choose to integrate into their teaching experience. Our results showed that preservice teachers chose to focus on four aspects of scientific practices: (1) employing historical understanding of how the theory emerged, (2) encouraging the use of evidence to build up a theory, (3) observation and interpretation of data maps, and (4) collaborative practices in making up the theory. For each of these practices, we also looked at the common challenges faced by preservice teachers by using constant comparative analysis. We observed the practices that preservice teachers decided to use and the challenges they faced, which were determined by what might have come as in their personal history as learners. Therefore, in order to strengthen preservice teachers' background, college courses should be arranged to teach important scientific ideas through scientific practices. In addition, such practices should also reflect the authentic practices of earth scientists such as use of historical record and differentiating observation versus interpretation.  相似文献   
169.
Nanotechnology has been touted as the next ‘industrial revolution’ of our modern age. In order for successful research, development, and social discourses to take place in this field, education research is needed to inform the development of standards, course development, and workforce preparation. In addition, there is a growing need to educate citizens and students about risks, benefits, and social and ethical issues related to nanotechnology. This position paper describes the advancements that have been made in nanoscale science and nanotechnology, and the challenges that exist to educate students and the public about critical nanoscience concepts. This paper reviews the current research on nanotechnology education including curricula, educational programs, informal education, and teacher education. Furthermore, the unique risks, benefits and ethics of these unusual technological applications are described in relation to nanoeducation goals. Finally, we outline needed future research in the areas of nanoscience content, standards and curricula, nanoscience pedagogy, teacher education, and the risks, benefits, and social and ethical dimensions for education in this emerging field.  相似文献   
170.
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