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51.
Free iron in serum has been found in several disease conditions including diabetes. In the present work, we studied the relationship between free iron, fasting blood glucose (FBG) and glycated haemoglobin (HbA1c). Study was carried out on 50 type 2 diabetes cases under poor glycemic control associated with complications, 53 type 2 diabetes cases under good glycemic control and 40 healthy controls. We estimated free iron, both ferrous (Fe+2) and ferric (Fe+3) form, protein thiols, lipid hydroperoxides, FBG, HbA1c and serum ferritin levels in serum. There was a significant increase in free iron in Fe+3 state (p <0.01), HbA1c (p<0.01), serum ferritin (p<0.01), lipid hydroperoxides (p<0.01) and significant decrease in protein thiols (<0.01) in diabetes cases under poor glycemic control compared to diabetes cases under good glycemic control and healthy controls. Free iron correlated positively with HbA1c (p<0.01). Poor glycemic control and increase in glycation of haemoglobin is contributing to the increase in free iron pool which is known to increase oxidant generation.  相似文献   
52.
The ever increasing presence of online social networks in users’ daily lives has led to the interplay between users’ online and offline activities. There have already been several works that have studied the impact of users’ online activities on their offline behavior, e.g., the impact of interaction with friends on an exercise social network on the number of daily steps. In this paper, we consider the inverse to what has already been studied and report on our extensive study that explores the potential causal effects of users’ offline activities on their online social behavior. The objective of our work is to understand whether the activities that users are involved with in their real daily life, which place them within or away from social situations, have any direct causal impact on their behavior in online social networks. Our work is motivated by the theory of normative social influence, which argues that individuals may show behaviors or express opinions that conform to those of the community for the sake of being accepted or from fear of rejection or isolation. We have collected data from two online social networks, namely Twitter and Foursquare, and systematically aligned user content on both social networks. On this basis, we have performed a natural experiment that took the form of an interrupted time series with a comparison group design to study whether users’ socially situated offline activities exhibited through their Foursquare check-ins impact their online behavior captured through the content they share on Twitter. Our main findings can be summarised as follows (1) a change in users’ offline behavior that affects the level of users’ exposure to social situations, e.g., starting to go to the gym or discontinuing frequenting bars, can have a causal impact on users’ online topical interests and sentiment; and (2) the causal relations between users’ socially situated offline activities and their online social behavior can be used to build effective predictive models of users’ online topical interests and sentiments.  相似文献   
53.
The need for cell and particle sorting in human health care and biotechnology applications is undeniable. Inertial microfluidics has proven to be an effective cell and particle sorting technology in many of these applications. Still, only a limited understanding of the underlying physics of particle migration is currently available due to the complex inertial and impact forces arising from particle–particle and particle–wall interactions. Thus, even though it would likely enable significant advances in the field, very few studies have tried to simulate particle-laden flows in inertial microfluidic devices. To address this, this study proposes new codes (solved in OpenFOAM software) that capture all the salient inertial forces, including the four-way coupling between the conveying fluid and the suspended particles traveling a spiral microchannel. Additionally, these simulations are relatively (computationally) inexpensive since the arbitrary Lagrangian–Eulerian formulation allows the fluid elements to be much larger than the particles. In this study, simulations were conducted for two different spiral microchannel cross sections (e.g., rectangular and trapezoidal) for comparison against previously published experimental results. The results indicate good agreement with experiments in terms of (monodisperse) particle focusing positions, and the codes can readily be extended to simulate two different particle types. This new numerical approach is significant because it opens the door to rapid geometric and flow rate optimization in order to improve the efficiency and purity of cell and particle sorting in biotechnology applications.  相似文献   
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55.
The current status of academic publishing is worrying. Cybercriminals are now targeting academic audiences, making it necessary to inform both editors and authors about such issues. The latest involves bogus impact factors, which are challenging scholarly publishing. Legitimate impact factors are used by authors and editors to get a general idea of the audience, if any, for a particular piece or journal. The bogus metrics only add confusion in support of the cybercrimes of their initiators. In this paper, we discuss bogus impact factors, victim countries, and try to clarify the phenomena for both authors and editors.  相似文献   
56.
As classrooms become increasingly diverse in higher education, educators are emphasising inclusive practices in teaching and learning to accommodate the needs of diverse learners. There is also an emerging need for an inclusive approach in assessment for accessibility, opportunity, relevance and engagement. This study, using design-based research guidelines with student–faculty partnership, designed, developed, implemented and evaluated contextually sensitive assessment protocol as inclusive and fair assessment. Data from students’ reflections and face-to-face interviews with open-ended questions suggested that, despite concerns such as potential bias, time and accommodation challenges, such assessment practices can make valuable contributions in creating a positive learning environment, improving relatedness and self-esteem and motivating and engaging students for better effort and effective learning. Implications for higher education practitioners with diverse learners are discussed.  相似文献   
57.
The objective of the investigation was to study the application of ultrasound reactor technology (USRT) as a disinfectant for reduction of fungi from sewage effluent. Fungi are carbon heterotrophs that require preformed organic compounds as carbon sources. USRT is an attractive means to improve water quality because of the system simplicity and no production of toxic by-products. An ultrasound reactor produces strong cavitation in aqueous solution causing shock waves and reactive free radicals by the violent collapse of the cavitation bubble. These effects should contribute to the physical disruption of microbial structures and inactivation of organisms. There was significant reduction in fungal growth, with decreased fungal growth with increasing USRT. In this study, ultrasound irradiation at a frequency of 42 kHz was used to expose suspensions of fungi to evaluate the disinfection efficacy of the ultrasound reactor. Also, this study showed that in this system more than 99% reduction of sewage fungi was achieved after 60 min.  相似文献   
58.
The proliferation of predatory or bogus journals has been recognized as a threat to academic research, and this study was conducted to discover the experiences of authors published in these journals. Eighty authors who had published in journals identified as predatory were surveyed. We asked how the authors learnt about these journals, what they thought about the reputation of the journals, their experiences of peer review and the quality of feedback provided, and whether publication was driven by PhD or job requirements. Our results showed that a third of authors discovered the journals by web searches or responding to email invitations. Over half said the reputation and name of the journal were important in selecting a journal, although a third admitted that the journal they published in did not have a good reputation. The main reason for selecting the journals was the promise of fast publication (31.2% respondents). Only half of the respondents said that publication was driven by PhD or job requirements. Just over a third reported that peer review was good or excellent, and only 17.5% said that peer review was poor or non‐existent – over 70% thought they had received good feedback from the journals. Although the research was somewhat limited, it does indicate general satisfaction with the journals in which the authors published. Fast publication coupled with good feedback and encouragement to submit can make publishing in predatory journals so tempting that few authors can resist.  相似文献   
59.
E-Government and E-Government development project studies have been conducted in most industrialized societies, as well as in Iran. Due to their nature and structure, E-Government development projects have numerous political, social, and economic impacts on society. Given the incorporation of significant capital, human resources, information, and political commitments, these projects are considered quite vital to society. Following the systematic pre-implementation activities of E-Government development projects is critical for the success of such projects; ignoring such issues leads to various problems during E-Government project implementation. This research aims to explore and detect the success indicators for pre-implementation activities of E-Government development projects, evaluate the validity of these indicators, and investigate the indicators' status in the Fuel Smart Card Project. The researcher has also provided some suggestions on the successful implementation of E-Government development projects.  相似文献   
60.
Cinnamon has been used as an anti-diabetic agent for centuries but only in recent few years its mechanism of action has been under investigation. Previous studies showed that cinnamon might exert its anti-diabetic effect via increasing glucose transporter isotype-4 (GLUT4) gene and glycoprotein contents in fat cells. To study if hydro-alcoholic cinnamon extract (HACE) enhances GLUT4 translocation from intracellular compartments of nuclear or endoplasmic reticulum membranes (N/ER) into the cytoplasmic membrane (CM). C2C12 myoblastic cell line were seeded in DMEM plus 20 % FBS and differentiated to myotubes using 2 % horse serum. After myotubes formation, 100 or 1,000 μg/ml HACE, as intervention, and as control 1 % DMSO were added for 3 h. Cells were washed and homogenized followed by ultracentrifuge fractionation, protein separation by SDS-PAGE and GLUT4 detection using semi-quantitative Western blotting. Data analysis was done by two-independent samples t test for comparison of mean ± SD of GLUT4 percent in categories. GLUT4 contents were higher in CM of groups 100 and 1,000 μg/ml HACE and lower in 1 % DMSO treated myotubes (CI = 0.95, P < 0.05). For N/ER reverse results were obtained (CI = 0.95, P < 0.05). As our results have shown HACE induces GLUT4 translocation from intra-cell into cell surface. We conclude that cinnamon maybe a choice of type-2 diabetes mellitus treatment because its extract enhances GLUT4 contents in CM where it facilitates glucose entrance into the cell. However it is necessary to trace the signaling pathways which are activated by HACE in muscular tissue.  相似文献   
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