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81.
Multi-document discourse parsing aims to automatically identify the relations among textual spans from different texts on the same topic. Recently, with the growing amount of information and the emergence of new technologies that deal with many sources of information, more precise and efficient parsing techniques are required. The most relevant theory to multi-document relationship, Cross-document Structure Theory (CST), has been used for parsing purposes before, though the results had not been satisfactory. CST has received many critics because of its subjectivity, which may lead to low annotation agreement and, consequently, to poor parsing performance. In this work, we propose a refinement of the original CST, which consists in (i) formalizing the relationship definitions, (ii) pruning and combining some relations based on their meaning, and (iii) organizing the relations in a hierarchical structure. The hypothesis for this refinement is that it will lead to better agreement in the annotation and consequently to better parsing results. For this aim, it was built an annotated corpus according to this refinement and it was observed an improvement in the annotation agreement. Based on this corpus, a parser was developed using machine learning techniques and hand-crafted rules. Specifically, hierarchical techniques were used to capture the hierarchical organization of the relations according to the proposed refinement of CST. These two approaches were used to identify the relations among texts spans and to generate multi-document annotation structure. Results outperformed other CST parsers, showing the adequacy of the proposed refinement in the theory.  相似文献   
82.
Deficiency or excess of certain trace elements has been considered as risk factor for prostate cancer. This study was aimed to detect differential changes and mutual correlations of selected trace elements in prostate cancer tissue versus benign prostatic hyperplasia tissue. Zinc, copper, iron, calcium and selenium were analysed in histologically proven 15 prostate cancer tissues and 15 benign prostatic hyperplasia tissues using atomic absorption spectrophotometer. Unpaired two tailed t test/Mann–Whitney U test and Pearson correlation coefficient were used to compare the level of trace elements, elemental ratios and their interrelations. As compared to benign prostatic tissue, malignant prostatic tissue had significantly lower selenium (p = 0.038) and zinc (p = 0.043) concentrations, a lower zinc/iron ratio (p = 0.04) and positive correlation of selenium with zinc (r = 0.71, p = 0.02) and iron (r = 0.76, p = 0.009). Considerably divergent interrelationship of elements and elemental ratios in prostate cancer versus benign prostatic hyperplasia was noted. Understanding of differential elemental changes and their interdependence may be useful in defining the complex metabolic alterations in prostate carcinogenesis with potential for development of element based newer diagnostic, preventive and therapeutic strategies. Further studies may be needed to elucidate this complex relationship between trace elements and prostate carcinogenesis.  相似文献   
83.
Isolation and enrichment of low-abundant particles are essential steps in many bio-analytical and clinical applications. In this work, the capability of an insulator-based dielectrophoresis (iDEP) device for the detection and stable capture of low abundant polystyrene particles and yeast cells was evaluated. Binary and tertiary mixtures of particles and cells were tested, where the low-abundant particles had concentration ratios on the order of 1:10 000 000 compared to the other particles present in the mixture. The results demonstrated successful and stable capture and enrichment of rare particles and cells (trapping efficiencies over 99%), where particles remained trapped in a stable manner for up to 4 min. A device with four reservoirs was employed for the separation and enrichment of rare particles, where the particles of interest were first selectively concentrated and then effectively directed to a side port for future collection and analysis. The present study demonstrates that simple iDEP devices have appropriate screening capacity and can be used for handling samples containing rare particles; achieving both enrichment and isolation of low-abundant particles and cells.  相似文献   
84.
Currently, medical education context poses different challenges to anatomy, contributing to the introduction of new pedagogical approaches, such as computer-assisted learning (CAL). This approach provides insight into students' learning profiles and skills that enhance anatomy knowledge acquisition. To understand the influence of anatomy CAL on spatial abilities, a study was conducted. A total of 671 medical students attending Musculoskeletal (MA) and Cardiovascular Anatomy (CA) courses, were allocated to one of three groups (MA Group, CA Group, MA + CA Group). Students' pre-training and post-training spatial abilities were assessed through Mental Rotations Test (MRT), with scores ranging between 0-24. After CAL training sessions, students' spatial abilities performance improved (9.72 ± 4.79 vs. 17.05 ± 4.57, P < 0.001). Although male students in both MA Group and CA Group show better baseline spatial abilities, no sex differences were found after CAL training. The improvement in spatial abilities score between sessions (Delta MRT) was correlated with Musculoskeletal Anatomy training sessions in MA Group (r = 0.333, P < 0.001) and MA + CA Group (r = 0.342, P < 0.001), and with Cardiovascular Anatomy training sessions in CA Group (r = 0.461, P = 0.001) and MA + CA Group (r = 0.324, P = 0.001). Multiple linear regression models were used, considering the Delta MRT as dependent variable. An association of Delta MRT to the amount of CAL training and the baseline spatial abilities was observed. The results suggest that CAL training in anatomy has positive dose-dependent effect on spatial abilities.  相似文献   
85.
Evidence from Australia lends support to the “Asian high achieving syndrome” in Chinese-Australian students and “self-deprivation syndrome” in Anglo-Australian students. Applying ethnographic case studies approach for doctoral thesis the author collected data on a longitudinal basis from homes and school of these students. All of these students attended the same school located in a predominantly middle class suburb of Perth Metropolitan area in Western Australia. Chinese-Australian families had settled in Perth from Malaysia, Singapore and Hong Kong, whereas Anglo-Australian families had been residing in Perth for three generations. Impetus to revisit these students (now young adults with their own families) 10 years later came from an urge to test the validity of the prediction the author had made in the concluding chapter of his doctoral thesis. The author had claimed that “if Anglo-Australian parents keep on dwelling in the era of 1950s and 1960s and do not change their laid-back attitude about education, their children could eventually be under-privileged in their own country”. Ten years later, the author undertook a follow-up study on these young adults from six of the eight original families in order to find out their occupational destinations and future aspirations. Data for the follow-up study were collected from these young adults and their parents. These research cases were interviewed twice, each time approximately for two hours and their parents were interviewed once for two to three hours. The purpose of this paper is to report the findings of the follow-up study which reveals a remarkable relationship between the attitude towards schooling and academic performance with their subsequent occupational destination.  相似文献   
86.
This paper introduces a framework and methodology for establishing indicators and metrics in order to assess the quality and performance of one-stop e-Government service offerings. The set of quality and performance indicators and metrics proposed has been derived in an outcomes assessment approach, based on the perspectives of e-Government service providers and end-users and following a goal-question-metric line of work that departs from some key quality and performance benefits. A methodology that employs the proposed framework to set improvement targets according to alternative scenarios is presented, and a strategy is elaborated for analyzing root causes of potential quality and performance shortcomings and undertaking appropriate countermeasures. Some results of application in a real case study, in the context of an EU-funded R&D project, are also provided. Finally, recommendations are given about usefulness of the proposed approach for e-Government service providers, as well as policy and decision-makers, and directions of future work are discussed in order to enhance the conceptual coverage of this approach, while at the same time not compromising its simplicity of application and generality of purpose.  相似文献   
87.
美国图书馆协会的<职业道德规范声明>提出了以图书馆事业为中心的具体原则,其<图书馆权利法案>则明确了图书馆的责任和义务.目前,美国社会和政治环境的变化为图书馆职业带来了越来越多的忧虑和压力."9·11"后出台的<爱国者法案>明显与图书馆职业道德规范中所阐述的重要原则相冲突.因此,美国图书馆协会决心抵制<爱国者法案>对知识、信息自由开放以及行使个人隐私权的限制.  相似文献   
88.
Reflexivity is a learning process that, through questioning and critically monitoring objectives and methods in use, promotes a change of habits and routines and, in so doing, fosters organizational performance and innovativeness. This paper looks at the contribution of team reflexivity to enhancing openness to innovation, and the mediating role of individual and team involvement. Specifically we tested whether affective commitment (Study 1, n=156) and a team climate of support for innovation (Study 2, n=152) facilitate reflexivity processes in promoting organizational openness to innovation. Overall, results confirmed that reflexivity enhances innovativeness, and this relationship is mediated by a high degree of involvement that increases the motivation of teammates and their engagement in innovation processes.  相似文献   
89.
90.
From January 1992-January 1998, 1404 patients attended the “Breast Clinic” of R.N.T. Medical College M.B. Hospital, Udaipur. Out of these, 11% and 81% patients had breast cancer (B.C.) and benign breast cancer (B.B.D.) respectively. The oxidative load in B.C. was 2.32 times higher than controls, but comparable to B.B.D. β-Carotene deficiency was uncommon in patients, whereas vitamin A deficiency was almost equally common in both B.C. and controls. Most of the patients had almost depleted levels of α-tocopherol and ascorbic acid but their TBAR levels were in normal range. The data in the present study when compared with B.B.D. and other local normal subjects point out: a) oxidative burden in B.C. is a consequence and not the cause of the disease, (b) oxidative stress could be one of the etiological factors in tumor expression, which need not to be malignant and c) α-tocopherol and ascorbic acid are not importantly responsible for higher oxidative burden in B.C.  相似文献   
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