全文获取类型
收费全文 | 22918篇 |
免费 | 361篇 |
国内免费 | 15篇 |
专业分类
教育 | 16349篇 |
科学研究 | 2032篇 |
各国文化 | 218篇 |
体育 | 1903篇 |
综合类 | 13篇 |
文化理论 | 175篇 |
信息传播 | 2604篇 |
出版年
2022年 | 180篇 |
2021年 | 261篇 |
2020年 | 382篇 |
2019年 | 601篇 |
2018年 | 827篇 |
2017年 | 800篇 |
2016年 | 700篇 |
2015年 | 420篇 |
2014年 | 658篇 |
2013年 | 4429篇 |
2012年 | 636篇 |
2011年 | 646篇 |
2010年 | 469篇 |
2009年 | 485篇 |
2008年 | 539篇 |
2007年 | 480篇 |
2006年 | 426篇 |
2005年 | 408篇 |
2004年 | 367篇 |
2003年 | 357篇 |
2002年 | 341篇 |
2001年 | 476篇 |
2000年 | 393篇 |
1999年 | 359篇 |
1998年 | 203篇 |
1997年 | 210篇 |
1996年 | 240篇 |
1995年 | 235篇 |
1994年 | 181篇 |
1993年 | 200篇 |
1992年 | 321篇 |
1991年 | 298篇 |
1990年 | 298篇 |
1989年 | 298篇 |
1988年 | 255篇 |
1987年 | 301篇 |
1986年 | 265篇 |
1985年 | 304篇 |
1984年 | 246篇 |
1983年 | 211篇 |
1982年 | 190篇 |
1981年 | 163篇 |
1980年 | 153篇 |
1979年 | 258篇 |
1978年 | 182篇 |
1977年 | 168篇 |
1976年 | 153篇 |
1975年 | 141篇 |
1974年 | 147篇 |
1971年 | 140篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Taylor M. Weiskittel Nirusha Lachman Anjali Bhagra Kylie Andersen Jeff St. Jeor Wojciech Pawlina 《Anatomical sciences education》2021,14(3):377-384
The clinical use of ultrasound has dramatically increased, necessitating early ultrasound education and the development of new tools in ultrasound training and assessment. The goal of this study was to devise a novel low-resource examination that tested the anatomical knowledge and technical skill of early undergraduate medical students in a gross anatomy course. The team-based ultrasound objective structured practice examination (OSPE) was created as a method for assessing practical ultrasound competencies, anatomical knowledge, and non-technical skills such as teamwork and professionalism. The examination utilized a rotation of students through four team roles as they scanned different areas of the body. This station-based examination required four models and four instructors, and tested ultrasound skills in the heart, abdominal vessels, abdominal organs, and neck regions. A Likert scale survey assessed student attitudes toward the examination. Survey data from participants (n = 46) were examined along with OSPE examination grades (n = 52). Mean and standard deviations were calculated for examination items and survey responses. Student grades were high in both technical (96.5%). and professional (96.5%) competencies with structure identification scoring the lowest (93.8%). There were no statistical differences between performances in each of the body regions being scanned. The survey showed that students deemed the examination to be fair and effective. In addition, students agreed that the examination motivated them to practice ultrasound. The team-based OSPE was found to be an efficient and student-favored method for evaluating integrated ultrasound competencies, anatomical knowledge, team-work, and professional attributes. 相似文献
992.
993.
Newly hatched chicks were force-fed food and water throughout rearing, and food, water, or sand reinforcers during exposure to an omission-training procedure. The chicks were thus prevented from performing approach and contact responses to the reinforcer at any time in their lives. Nevertheless, the subjects displayed approach and species-specific feeding or drinking reactions directed toward an illuminated key paired with food or water, but not with sand. Illumination of a key either uncorrelated or negatively correlated with food or water did not engender appreciable responding. Feeding and drinking reactions were topographically distinct, determined by the type of reinforcer, but were not elicited by the reinforcer. These findings support a “learned release” view of autoshaping, according to which phylogenetically preorganized behavior patterns are triggered by distal stimuli paired with biologically significant proximal stimulation, and suggest a close relationship between autoshaping and primitive instances of visual object recognition. 相似文献
994.
Ian M. Harris 《The Urban Review》1982,14(1):25-33
This paper describes how an undergraduate department in the School of Education at the University of Wisconsin-Milwaukee grants college credits for previous learning experiences to attract and retain nontraditional students from an urban environment. At first students earned these credits by writing a loose biography, but the process by which these credits are earned has become more structured. These Prior Professional Educational Experience credits (as they are named) are now granted on a course-specific basis, where students respond in writing to questions designed to test their knowledge of competency areas offered by the department. Earning these credits has helped older students get through the university and has given them a sense of accomplishment about learnings acquired in nonuniversity settings. 相似文献
995.
Marcel?B.?M.?de?CroockEmail author Fred?Paas Henrik?Schlandbusch Jeroen?J.?G.?van?Merri?nboer 《Educational technology research and development : ETR & D》2002,50(4):47-58
This article describes a set of computerized tools that support the design and evaluation of competency-based training programs. The training of complex skills such as air traffic control and process control requires a competency-based approach that focuses on the integration and coordination of constituent skills and transfer of learning. At the heart of the training are authentic whole-task practice situations. The instructional design tools are based on van Merriënboer's 4C/ID* methodology (1997). The article describes a training design tool (Core) that supports the analysis and design for competency-based training programs and an evaluation tool (Eval) that supports the subsequent revision of this training design. 相似文献
996.
The aim of this study was to establish whether asymmetry of the strength of the leg and trunk musculature is more prominent in rowers than in controls. Nineteen oarsmen and 20 male controls matched for age, height and body mass performed a series of isokinetic and isometric strength tests on an isokinetic dynamometer. These strength tests focused on the trunk and leg muscles. Comparisons of strength were made between and within groups for right and left symmetry patterns, hamstring: quadriceps ratios, and trunk flexor and extensor ratios. The results revealed no left and right asymmetries in either the knee extensor or flexor strength parameters (including both isometric and isokinetic measures). Knee extensor strength was significantly greater in the rowing population, but knee flexor strength was similar between the two groups. No difference was seen between the groups for the hamstring: quadriceps strength ratio. In the rowing population, stroke side had no influence on leg strength. No differences were observed in the isometric strength of the trunk flexors and extensors between groups, although EMG activity was significantly higher in the rowing population. Patterns of asymmetry of muscle activity were observed between the left and right erector spinae muscles during extension, which was significantly related to rowing side (P < 0.01). These observations could be related to the high incidence of low back pain in oarsmen. 相似文献
997.
998.
Competence to work in schools is an important dimension of professional competence, although it is often a neglected dimension of teacher development. This article reports a qualitative study that examined student teachers’ learning experiences in initial teacher education (ITE) in relation to competence to work in schools. In-depth interviews were conducted with 12 student teachers on an undergraduate ITE programme in Hong Kong. The findings of the study show that competence to work in schools is characterised by student teachers’ deep contextualised learning. In addition, it offers a deeper understanding of this competence in the ITE context by identifying its three facets, namely understanding of the micro-political realities of schools, social capital building and social strategies. The study provides insights for ITE and schools to support student teachers’ development of their competence to work in schools, including the design of ITE curricula, ITE processes and co-curricular activities in undergraduate studies. Moreover, it suggests the importance of developing schools as growth-fostering and positive micro-political sites for ITE fieldwork and teacher induction. 相似文献
999.
C. G. Olesen B. H. Larsen E. L. Andresen M. de Zee 《European Journal of Sport Science》2015,15(3):242-247
AbstractThe aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance. 相似文献
1000.
Impact of National Aquarium in Baltimore on Visitors' Conservation Attitudes,Behavior, and Knowledge
This study at the National Aquarium in Baltimore (NAIB) was conducted to assess four key aspects of the visitor experience: (1) incoming conservation knowledge, attitudes, and behavior of NAIB visitors; (2) patterns of use and interaction with exhibition components throughout the NAIB; (3) exiting conservation knowledge, attitudes, and behaviors of visitors; and (4) over time, how the NAIB experience altered or affected individuals' conservation knowledge, attitudes, and behaviors. Three hundred six visitors participated in the study, which was conducted from March through July, 1999. The study utilized four data‐collection techniques: (1) face‐to‐face interviews, (2) Personal Meaning Mapping (PMM), (3) tracking, and (4) follow‐up telephone interviews. Participants were a self‐selected population and were generally more knowledgeable about, more concerned about, and more involved in conservation‐related issues than the general public. However, they were far from conservationists. Visitors in this study clearly absorbed the fundamental conservation message at the NAIB. In fact, the NAIB visit appeared to focus visitors' conservation‐related thoughts, while also broadening their understanding of conservation. Changes in visitors' conservation knowledge, understanding, and interests by and large persisted over six to eight weeks after visiting NAIB. The NAIB experience also connected to visitors' lives in a variety of ways following their visit. However, these personal experiences rarely resulted in new conservation actions. In fact, their enthusiasm and emotional commitment to conservation (inspired during the NAIB visit) generally fell back to original levels, presumably in the absence of reinforcing experiences. The findings of this study are guiding subsequent investigations at the NAIB. More generally, the results suggest strategies to enhance current understanding of the impact free‐choice learning institutions have on their visiting public. 相似文献