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971.
Prematurity and low birth weight (LBW) are two major biological factors that put infants and young children at high risk for developmental delays or disabilities. While survival rates for premature and LBW children have improved, incidence figures have changed little over the past 20 years; in fact, the incidence of LBW has increased. Although the vast majority of LBW children have normal outcomes, as a group, they have higher risk for subnormal growth, illnesses, and neurodevelopmental problems. The purpose of this article is to examine the factors that influence the effectiveness of early intervention for premature, LBW children and to describe a strategy for linking assessment and early intervention. Linking assessment and intervention involves comprehensive assessment; a team approach to both assessment and intervention; empowering and enabling families; and the development of functional goals and objectives.  相似文献   
972.
To maintain the legacy of cutting edge scientific innovation in the United States our country must address the many pressing issues facing science education today. One of the most important issues relating to science education is the under-representation of African Americans and Hispanics in the science, technology, and engineering workforce. Foreshadowing such under-representation in the workforce are the disproportionately low rates of African American and Hispanic students attaining college degrees in science and related fields. Evidence suggests disparate systemic factors in secondary science education are contributing to disproportionately low numbers of African American and Hispanic students in the science education pipeline. The present paper embarks on a critical analysis of the issue by elucidating some of the systemic factors within secondary education that contribute to the leak in the science education pipeline. In addition, this review offers a synthesis and explication of some of the policies and programs being implemented to address disparate systemic factors in secondary schools. Finally, recommendations are offered regarding potential mechanisms by which disparities may be alleviated.  相似文献   
973.
Using data from the 1998 High School National Census from the Ministry of Education and Culture of Argentina, the present study examines relationships between school composition, some characteristics of schooling (such as institutional culture and climate), and students’ achievement in Mathematics in the last year of high school. The study applies multilevel linear modeling on the levels of student, school and state. It finds a close relationship between achievement in Mathematics and the variables of school composition and schooling processes. It shows that when both variables act together, the effect of all other variables significantly decreases. The variables of schooling processes, however, even when diminished in influence, nonetheless notably continue to affect students’ achievements. The study also identifes a reference model for future studies evaluating other institutional factors of learning.  相似文献   
974.
A written questionnaire was used to obtain information regarding Greek kindergarten teachers’ personal views on the concept of Environmental Education (EE). The questionnaire was also designed to obtain the teachers’ views relative to a series of theoretical and methodological issues concerning the application of EE. It was ascertained that the prevalent conception of the kindergarten teachers includes the following: (a) it is directed towards a knowledge-centered type of EE, (b) it is primarily centered on nature and its protection in terms of EE content, (c) it aims not only to shape citizens willing to adopt environmental measures recommended by the experts, but who will also actively participate in social actions for the protection of the environment, (d) it favors learning procedures in the environment with field study activities, (e) it must be compulsory in the kindergarten level.  相似文献   
975.
:债转股是国家解决国有企业脱困、盘活边缘性不良资产、化解金融风险的重大经济措施 ,最终目的是将股权变现 ,提高企业的经营管理水平和经济绩效 ,减轻财政负担。但债转股不是债务赦免 ,债转股还存在着许多问题需要解决。我们必须采取有效的对策才能保证债转股工作的正常运行  相似文献   
976.
For an energy-efficient induction machine, the life-cycle cost (LCC) usually is the most important index to the consumer. With this target, the optimization design of a motor is a complex nonlinear problem with constraints. To solve the problem, the authors introduce a united random algorithm. At first, the problem is divided into two parts, the optimal rotor slots and the optimization of other dimensions. Before optimizing the rotor slots with genetic algorithm (GA), the second part is solved with TABU algorithm to simplify the problem. The numerical results showed that this method is better than the method using a traditional algorithm. Project (No. 601299) supported by the Science Foundation of Hebei Province, China.  相似文献   
977.
We present results from a classroom-based intervention designed to help a class of grade 10 students (14–15 years old) learn proof while studying trigonometry in a dynamic geometry software environment. We analysed some students’ solutions to conjecture-and-proof problems that let them gain experience in stating conjectures and developing proofs. Grounded on a conception of proof that includes both empirical and deductive mathematical argumentations, we show the trajectories of some students progressing from developing basic empirical proofs towards developing deductive proofs and understanding the role of conjectures and proofs in mathematics. Our analysis of students’ solutions is based on networking Boero et al.’s construct of cognitive unity of theorems, Pedemonte’s structural and referential analysis of conjectures and proofs, and Balacheff and Margolinas’ cK¢ model, while using Toulmin schemes to represent students’ productions. This combination has allowed us to identify several emerging types of cognitive unity/rupture, corresponding to different ways of solving conjecture-and-proof problems. We also show that some types of cognitive unity/rupture seem to induce students to produce deductive proofs, whereas other types seem to induce them to produce empirical proofs.  相似文献   
978.
The current study was designed to understand the development of comprehension monitoring among beginner readers from first to third grade, and to determine the extent to which first graders’ comprehension monitoring predicts reading comprehension in grade three. Participants were 113 children (57% female) from four US states who were followed from Grade 1 (M = 7 years, SD = 4 months) to Grade 3 (M = 9 years, SD = 4 months). Measures included decoding, vocabulary, working memory, comprehension monitoring, and reading comprehension. Children’s ability to monitor comprehension grew significantly from first to third grade, with a deceleration in growth over time. In addition, comprehension monitoring in Grade 1 made a significant contribution to reading comprehension in Grade 3, even after controlling for decoding, vocabulary, and working memory. Together, these findings supplement our understanding of young readers’ development of comprehension monitoring as well as its association with reading comprehension at a later time. Practical implications of the results in the context of providing support for higher-level language skills in beginning reading instruction are discussed.  相似文献   
979.
Biochemical changes of natural actomyosin from fresh pale, soft, exudative (PSE) and normal pork were studied, and the effects of different storage temperatures and different incubation temperature and times on sample superprecipitation, total sulfhydryl (-SH) content, and ATP (adenosine triphosphate) sensitivity were investigated. The results demonstrated that ATPase activity and thermal stability of PSE actomyosin were lower than those of normal pork; and that PSE actomyosin had higher -SH content than that of normal pork at all incubation temperatures and times tested.  相似文献   
980.
Defiant behavior in two- and three-year-olds is a natural expression of a young child’s growing autonomy, and, although frustrating to adults, is a natural phase of a child’s socio-emotional growth. L.S. Vygotsky’s socio-historical theory of the development included a discussion of “crisis” periods, one of which he felt occurred at age three. The crisis that Vygotsky asserted occurred at three is characterized by a group of seven “behaviors”, all of which indicate a struggle with the child’s position in relation to family social structures. This study examined the occurrences and characteristics of defiant behavior in two-and three-year-old children during outdoor play at a child development center, and the existence and context of defiant behaviors the modern childcare setting. Patterns in defiant behaviors during play in different age groups were apparent, and suggested an instrument to facilitate the documentation and analysis of defiant behavior in modern group-care settings.  相似文献   
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