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201.
Hemodynamic disorders of liver cirrhosis complicated with portal hypertension are associated with an increased angiogenesis in animal model of portal hypertension and cirrhosis which were linked to increased expression of vascular endothelial growth factor (VEGF) and nitric oxide (NO). The aim of study was to evaluate the serum concentration of VEGF and total nitric oxide (NO) in liver cirrhosis and the possible association with the degree of liver insufficiency. VEGF and NO were measured in serum of 64 patients with liver cirrhosis by ELISA and spectrophotometry respectively. The significant increase of serum VEGF was observed in liver cirrhosis compared to healthy individuals as well as serum NO (106.1 ± 66.7 vs. 41.5 ± 6 pg/mL, P < 0.05; 113.5 ± 65.8 vs. 20.8 ± 3.8 μmol/l, P< 0.001, respectively). Serum VEGF and NO showed significant associations with biochemical indices of liver function and with Child-pugh score where they were increased respectively to the degree of liver insufficiency. A significant association of raised serum NO in early stage of portal hypertension reflect its benefit in early expect of portal hypertension but, high serum VEGF in late stage may reflect its prognostic value in liver cirrhosis.  相似文献   
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ABSTRACT

The study purpose was to use Inertial Measurement Units (IMUs) to objectively assess children’s motor competence in seven movement skills. Fourteen children aged from seven to 12 years (M = 9.64) participated. Children were asked to perform up to 10 trials of each skill. Children performed the skills, which were captured by XSENS MVN Awinda wireless motion capture, and video. Skills were assessed from video as per the criteria from the Test of Gross Motor Development 3. Initially, 17 IMU sensors were used for signal processing, but this was restricted to four sensors (wrists and ankles) to be more feasible for field assessment. Results of the signal testing against its modelled “Good” signal, showed the skip was classified correctly each time, as was the sidestep. Accuracy % rates for each skill were: kick (95.2), catch (95.0), throw (80.5), jump (78.9), and hop (76.9). Using signal processing-based methods via four sensors was a reliable and feasible way to assess seven motor skills in children. This approach means monitoring and assessment of children’s skills can be objective, which will potentially reduce the time involved in motor skill assessment and analysis for research, clinical, sport and education purposes.  相似文献   
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Question-answering has become one of the most popular information retrieval applications. Despite that most question-answering systems try to improve the user experience and the technology used in finding relevant results, many difficulties are still faced because of the continuous increase in the amount of web content. Questions Classification (QC) plays an important role in question-answering systems, with one of the major tasks in the enhancement of the classification process being the identification of questions types. A broad range of QC approaches has been proposed with the aim of helping to find a solution for the classification problems; most of these are approaches based on bag-of-words or dictionaries. In this research, we present an analysis of the different type of questions based on their grammatical structure. We identify different patterns and use machine learning algorithms to classify them. A framework is proposed for question classification using a grammar-based approach (GQCC) which exploits the structure of the questions. Our findings indicate that using syntactic categories related to different domain-specific types of Common Nouns, Numeral Numbers and Proper Nouns enable the machine learning algorithms to better differentiate between different question types. The paper presents a wide range of experiments the results show that the GQCC using J48 classifier has outperformed other classification methods with 90.1% accuracy.  相似文献   
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E‐learning tools and technologies have been used to supplement conventional courses in higher education institutions creating a “hybrid” e‐learning module that aims to enhance the learning experiences of students. Few studies have addressed the acceptance of hybrid e‐learning by learners and the factors affecting the learners’ satisfaction with these tools. This study assesses hybrid e‐learning acceptance by learners using three critical success factors: instructor characteristics, information technology infrastructure, and organizational and technical support. Structural equation modeling was applied to examine and validate the hypothesized relationships among the three factors and their effects on learners’ acceptance of hybrid e‐learning. A total of 538 usable responses from university students were used to validate the proposed research model. The influence of the three factors on learners’ decision to accept hybrid e‐learning was empirically examined. The results show that all three factors significantly and directly impacted the learners’ acceptance of hybrid e‐learning courses. Information technology infrastructure and organizational support were proven to be key determinants of the instructor characteristics as a critical success factor of hybrid e‐learning acceptance by learners. Implications of this work for higher education institutions, researchers, and instructors are described.  相似文献   
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The main objective of the current study is to examine the role of the statistical relation between BCL2 gene (Ala43Thr) single nucleotide polymorphism and growth hormone (GH1) levels in Egyptian HCV genotype-4 patients before and after treatment with pegylated interferon plus ribavirin. Eighty patients with HCV genotype-4 and 40 healthy volunteers as controls were enrolled in the prospective study. Gene polymorphism of BCL2 (Ala43Thr) using PCR-RFLP technique and GH1 concentrations using ELISA procedure were measured for all patients and controls. The present study resulted that Responder HCV genotype-4 Patients, with BCL2 43Ala genotype, have high significant increase in pre-treatment GH1 levels (>1 ng/ml); which represent normal levels, as compared to non-responders pre-treatment GH1 levels (<1 ng/ml); which represent low concentrations. We concluded that HCV genotype-4 patients who have normal GH1 concentrations and BCL-2 43Ala genotype can successfully achieve response to interferon based therapy.  相似文献   
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Inclusive education (IE) and the special education services related to it are relatively new in Oman. Efforts to manage special/inclusive education face many challenges due to a number of culturally rooted factors. Further, empirical research on IE in Oman is scarce and there is a need to advance IE discourse based on empirically validated perspectives. This article examines how IE is managed in schools from the perspective of school leaders in order to develop a framework for action. The author conducted a preliminary qualitative inquiry into how IE is understood and managed in Key stage 1 schools in Oman. The inquiry was based on a focus group interview with a cohort of 25 school leaders who were completing a two year bachelor in educational administration, an endorsement‐like programme at Sultan Qaboos University. Findings showed a number of challenges and tensions between theory and practice, highlighted by school leaders. These challenges and tensions were analysed in order to map out strengths and difficulties. A three level prism shaped framework for action was developed based on the analysis. The framework for action could potentially serve to guide policy‐ and decision‐makers, researchers, practitioners, and is advocated to develop a model of best practice for the successful implementation and management of IE in Oman.  相似文献   
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There is a high demand to develop and incorporate decision support tools, by the transportation sectors and other concerned agencies, to improve their infrastructure assets management under shrinking budgets and increasing demands. This paper develops a proof-of-concept Bayesian belief network (BBN) model to rank roads in a network system based on several key performance indicators (KPI) using a probabilistic framework. For a given road network, the proposed tool is capable of ranking or prioritizing the segment of roads for high level management objectives. To demonstrate the application of the proposed model, various scenarios are elaborated and discussed in detail. Finally, the sensitivity analysis is carried out to evaluate the effects of different KPIs.  相似文献   
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