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741.
Self-assessment and task-selection skills are crucial in self-regulated learning situations in which students can choose their own tasks. Prior research suggested that training with video modeling examples, in which another person (the model) demonstrates and explains the cyclical process of problem-solving task performance, self-assessment, and task-selection, is effective for improving adolescents’ problem-solving posttest performance after self-regulated learning. In these examples, the models used a specific task-selection algorithm in which perceived mental effort and self-assessed performance scores were combined to determine the complexity and support level of the next task, selected from a task database. In the present study we aimed to replicate prior findings and to investigate whether transfer of task-selection skills would be facilitated even more by a more general, heuristic task-selection training than the task-specific algorithm. Transfer of task-selection skills was assessed by having students select a new task in another domain for a fictitious peer student. Results showed that both heuristic and algorithmic training of self-assessment and task-selection skills improved problem-solving posttest performance after a self-regulated learning phase, as well as transfer of task-selection skills. Heuristic training was not more effective for transfer than algorithmic training. These findings show that example-based self-assessment and task-selection training can be an effective and relatively easy to implement method for improving students’ self-regulated learning outcomes. Importantly, our data suggest that the effect on task-selection skills may transfer beyond the trained tasks, although future research should establish whether this also applies when trained students perform novel tasks themselves.  相似文献   
742.
Intraperitoneal administration of glucose (20%), Sucrose (20%) and mannitol (15%) to the rats, at a dose of 5ml/100g body weight 3 hrs. prior to hypoxic exposure (simulated high altitude 10,973m, 32°C) significantly increased the hypoxic tolerance. Intraperitoneal administration of these solutions resulted in accumulation of transudate fluid in the peritoneal cavity. A decrease in the excretion of urine, increase in hematocrit value, haemoglobin level, blood viscosity and serum protein were observed. Moisture content of lungs amongst other tissue was found to be decreased. Results are suggestive that dialysis across the peritoneal membrane might have removed some material from the blood in the peritoneal fluid which might have been responsible for the increased hypoxic tolerance.  相似文献   
743.
How does the University sector identify and support the diverse needs of Indian students? This paper reports on a research project carried out on undergraduate students from India enrolled at a Melbourne‐based University. The focus is the need to understand why Indian students choose an overseas destination for tertiary study. The intent is to explore how the curriculum that they have experienced in their country prepares them for study in another. We examine the expectations of students in relation to studying overseas. The suggestion underlying this paper is that if academic and support staff in tertiary education understand international students in cultural cohorts, then it is more likely that their transition to tertiary education will be easier. We envisage that this may also lead to a greater retention rate for universities.  相似文献   
744.
Background: The Polish Medical Bibliography (Polska Bibliografia Lekarska) contains 350 000 records dating from 1979. These records from the fields of medicine, nursing, dentistry, health care systems and preclinical sciences are from nearly 300 biomedical journals published in Poland. Methods: We systematically searched the Polish Medical Bibliography Part II (1996–2006) CD‐ROM (July 2006) using both English and Polish phrases for randomized trials, manually checked results and, for the trials identified in this way, sought these on medline and embase . Results: Systematic searching identified records of 680 randomized trials from all areas of health care. Nearly 40% of these were not found on either medline or embase . Conclusions: The Polish Medical Bibliography should be of interest to health care information specialists concerned with comprehensive searches for trials.  相似文献   
745.
The proliferation of mobile computing technologies is playing major role in the growth of mobile learning (M-learning) market around the globe. The purpose of this paper is to develop a research model in the lines of commonly used models the Unified Theory of Acceptance and Use of Technology (UTAUT) and Technology Acceptance Model (TAM) by incorporating constructs namely flexibility learning, social learning, efficiency learning, enjoyment learning, suitability learning, and economic learning that can predict M-learning adoption in a developing country. The data were collected from 388 students from all major universities/colleges in the capital city (Muscat) of Oman. The neural network modeling was employed to predict M-learning adoption. The neural network modeling results showed that flexibility learning, social learning, efficiency learning, enjoyment learning, suitability learning, and economic learning variables have significant influence on the intention of students to accept mobile learning. The key outcomes of this study suggest important determinants that can assist academic administrators and telecommunication service providers to enhance the adoption of M-learning with the help of suitable strategy.  相似文献   
746.
Adenosine deaminase activity (ADA) was estimated in cerebrospinal fluid (CSF) of 30 patients of tuberculous meningitis (TBM) and 10 patients each of partially treated pyomeningitis (PTM), aseptic meningitis (AM) and pyogenic meningitis (PM). Mean ADA levels in CSF of TBM patients were higher (18.22 U/L) as compared to 6.28 U/L, 3.43 U/L and 7.98 U/L in PTM, AM and PM respectively. This difference of ADA values in CSF between TBM and other types of meningitis was statistically significant (p<0.01) different. Sensitivity and specificity of ADA levels in CSF of children to diagnose tuberculous meningitis was 66.6% and 90% respectively at 10 U/L cut off of ADA levels in CSF. ADA levels in CSF could also differentiate PTM, AM and PM from TBM with a specificity of 90%, 100% and 80% respectively.  相似文献   
747.
An external quality assessment was conducted for RIA of thyroid related hormones. Thirtyfive laboratories (35 for T4, 34 for T3 and 23 for TSH) from different parts of country participated in the programme. Twentyfour samples (16 pools: 5 simple and 11 manipulated pools) in 8 batches, 3 per batch per month were sent for analysis of T4, T3 and TSH. Some of the samples were repeated 3 times at different occasions to assess the imprecision of the laboratory. The overall mean percent CV obtained for T4, T3 and TSH were 22.7, 36.32 and 52.38 respectively. The recovery for added T4 was 86.73% while that for T3 was 117.4%. A large variation was obtained for recovery of TSH. For T4 estimations, 13 laboratories had a desirable performance i. e. bias less than ±10.0% and variability of bias (VB) and imprecision (IP) less than 15.0%. None of the laboratories had a desirable performance for T3 or TSH. The number of laboratories with acceptable performance i. e. bias between ±10.0–15.0%, VB and IP between 20.0–25.0% for T4, T3 and TSH were 4, 3 and 0 respectively. The number of laboratories which required attention (bias between ±15.0–20.0%; VB and IP between 20.0–25.0%) were 5,7 and 1 respectively. The unacceptable results with larger bias, VB and IP for T4, T3 and TSH were 6, 18 and 17 respectively. Our results are in general agreement that the performance of T4 assay is better than T3 and both in turn are much better than TSH. Quantitation of circulating thyroid hormones (TH) viz. tri-iodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH), which form the largest percentage of hormones estimated in a clinical laboratory is mainly done by radio-immunoassay (RIA) procedures. The reliability and reproducibility of these assays are generally monitored by using internal quality control (IQC) samples in every assay batch. Thus, the IQC provides information whether the assay results are satisfactory and can be released. However, external quality assessment (EQA) is a procedure whereby an external agency undertakes evaluation of the quality of an analytical service by providing samples for analysis to individual laboratories performing the assay. The data gathered is analysed collectively. EQA therefore provides a means by which performance of a laboratory is assessed in relation to other laboratories and matching the assay unbiased by removing systematic error, if present. This is important since RIA procedure involves several steps (collection and storage of samples, quality of the reagents, procedure followed for performance of an assay, counting equipment used and the mode of the data analysis) and therefore prone to systematic errors. We therefore undertook the EQA programme for assessment of thyroid related hormones as a joint collaborative project of Bhabha Atomic Research Centre, India and International Atomic Energy Agency.  相似文献   
748.
In rats with streptozotocin induced severe diabetes mellitus, aqueous extract of Trichosanthes dioica fruits at a dose of 1000mg/kg body weight daily once for 28 days reduced the levels of fasting blood glucose, postprandial glucose, asparate amino transferase, alanine amino transferase, alkaline phosphatase, creatinine, urine sugar and urine protein where as total protein and body weight was increased. No toxic effect was observed during LD50. Our study suggests that further detailed toxicity studies and mechanism of action of T. dioica would be useful for undertaking human trials.  相似文献   
749.
In an increasingly globalizing and knowledge-based world economy, the declining importance of R&D activity in India is a matter of concern. This paper analyzes the determinants of R&D behaviour of Indian enterprises over the 1990s in the context of the reforms of 1991 and their impact on the R&D behaviour of MNE affiliates and local enterprises. The analysis suggests that although average levels of spending have fallen, increased competition due to liberalization seems to have pushed local firms to rationalize their R&D activity and make it more efficient. Also, R&D spending seems to rise more than proportionally with firm size after a certain threshold level has been reached. The analysis brings out differences in the nature of R&D activity of MNE affiliates and local firms. Local firms direct their R&D activity primarily towards the assimilation of imported technology, and to providing a backup to their outward expansion via exports and FDI. MNE affiliates, on the other hand, focus on exploiting the advantages of India as an R&D platform for their parents. The paper is concluded with some policy implications of the findings.  相似文献   
750.
逃跑的女孩     
Ru Yun and San Hua were best friends. They had been the best of friends for almost half their lives, at about fifteen years of age. They went to the same school, took the same bus and shared the same interests. They were always together like a pair of Siamese twins. Nothing could separate them, not even their studies or their parents,  相似文献   
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