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1.
BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease.  相似文献   
2.
Higher education as a personal, intellectual and moral cultivation is a longstanding ideal that is constantly challenged by the view that education is merely the development of specific skills for vocational and personal success. Much research argues that the latter understanding makes education a technical affair that creates an egocentric emphasis on the individual students’ ambitions and desires. This article joins in the defence of the former ideal by enquiring into the moral dimensions of education. This is done by turning to Iris Murdoch's idea of moral transformation, with a specific focus on the idea of unselfing. The main argument is that unselfing is a transformative process characterised by a growing attunement to the surrounding world, and the interconnectedness of goal and process is emphasised. Also, to gain a deeper understanding of what unselfing entails I turn to the idea of attention. It is understood as having a specific direction, outward from the egocentric, and as enabling unselfing. The article concludes by suggesting that unselfing can offer a challenge to (higher) education as it entails a moment of letting go of plans and narratives, and of surrendering to the influence of an existence that exceeds the individual. This moment is of relevance to education as it is crucial to the possibility of growing as a moral being as it cultivates a moral manner of relating to others.  相似文献   
3.
This study examined the mediating roles of children's callousness and negative internal representations of family relationships in associations between family instability and children's adjustment to school in early childhood. Participants in this multimethod (i.e., survey, observations), multiinformant (i.e., parent, teacher, observer), longitudinal study included 243 preschool children (Mage = 4.60 years) and their families. Findings from the lagged, autoregressive tests of the mediational paths indicated that both children's callousness and negative internal representations of family relationships mediated longitudinal associations between family instability and children's school adjustment problems over a 2‐year period (i.e., the transition from preschool to first grade). Findings are discussed in relation to the attenuation hypothesis (E. J. Susman, 2006) and emotional security theory (EST; P. T. Davies, M. A. Winter, & D. Cicchetti, 2006).  相似文献   
4.
For a long time after the proclamation of independence, Croatia suffered economic stagnation that negatively affected the development of science and higher education. However the turn of the millennium brought higher state investment in science and higher education, and all statistics now show a steady increase in the number of students and scientific personnel for the past several years. With these trends the focus has moved from the role the state can play in reviving science in Croatia to the necessity of greater participation in scientific funding, as well as the role that university graduates can play in the development of the country. The role of European integration and the brain drain phenomenon thus increase in importance, and this study provides some parameters for brain drain and the academic and intellectual labour market in Croatia.  相似文献   
5.
Assessing a student's acquisition rates (ARs) is a reliable way to determine how many new words should be taught in one lesson without reducing retention. Exceeding a student's AR can result in frustration and problem behaviors. The purpose of this study was to examine the effect of AR on the off‐task behavior of kindergarten students while participating in a commonly used sight‐word instruction video. Participants included 39 kindergarten students whose ARs were assessed before showing the sight‐word video. Behavior was measured as on‐ and off‐task using momentary time‐sampling with 10‐s intervals. Results indicated that students' time off task increased after exceeding their ARs, with a noticeable immediate increase. The implications and limitations of these results are discussed.  相似文献   
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7.
Learning progressions are theoretical models that describe learning of scientific ideas and practices over time. These hypothetical progressions need to be tested and refined in order to productively inform instruction and assessment. In this paper, we report our attempts to revise a learning progression in genetics. In particular, we focused on two constructs that embody core ideas in classical genetics and one molecular construct. The revisions are based on analysis of pre‐ and postinterview data obtained from sixty 11th grade students before and after they engaged in a 10‐week unit that addressed these concepts. We found that while many of the students held ideas that aligned with the progression, there were several distinct dimensions of student reasoning that were not captured and led to substantial revisions of the constructs including: (a) the splitting of the construct dealing with meiosis (E) into two subconstructs (E1‐physical passage of genetic information and E2 – the role of sex cells), (b) the addition of new levels to constructs dealing with the universal nature and organization of the genetic code (A) and construct (F). For Construct A, the lower levels were expanded to include ideas about the localization of DNA in cells and to include ideas about the composition of DNA that were not captured in the progression. Revisions to Construct F included the expansion of existing levels and the addition of modes of inheritance such as codominance and incomplete dominance. The research we present offers insights about a methodological approach that can be used to test and refine progressions, as well as insights about student learning in genetics as we further describe and expand the stepping‐stone ideas in the progression and discuss further the multidimensional nature of learning progressions.  相似文献   
8.
The agenda for widening participation in higher education has led to increasing numbers of students with a broader range of education and family backgrounds. However, transitioning to the university landscape remains a highly complex negotiation process, especially for first‐in‐family students, who cannot draw on previous experience from higher education in their families. Gaining access to informational capital—a combination of cultural and social capital—plays a crucial role in managing education transitions. We draw on rich empirical data obtained from 26 autobiographical narrative interviews with first‐in‐family university students in Austria to investigate how transitions to university are affected by informational capital. We also explore how access to informational capital was influenced by (1) institutional practices, such as initiatives to support students, especially first‐year students; and (2) cultural fit—the extent to which a student's cultural capital corresponded with the dominant cultural capital in the field of their chosen discipline or higher education establishment. Our findings show that gaining access to informational capital was strongly affected by the institutional practices at universities within the different disciplines, thus highlighting the importance of higher education institutions in supporting their students during transition processes. We conclude with policy implications for how higher education institutions can assist first‐in‐family students to succeed at university.  相似文献   
9.

Covid-19 literacy, induced by the coronavirus disease (2019), is characterized as the understanding of Covid-19 as well as informed decisions based upon this understanding. This type of literacy is closely related to health literacy, scientific literacy, and scientific media literacy. It may be obvious to say that Covid-19 literacy is a key factor for governments to effectively manage the Covid-19 transition. However, lack of literature exists about Covid-19 literacy among university students. Therefore, the current study aimed to determine the Covid-19 literacy level among 4168 students from a Colombian university. The data were derived from students’ responses to a 25–item anonymous online self-reporting questionnaire. We found that 21–25-year age group, graduate students,?students enrolled prior to 2015, and medical students had a significantly higher mean score. Moreover, the Internet (86.8%) was the most popular source of information from which participants gained most information regarding Covid-19. Furthermore, 58.5% of the participants considered health workers as a source that can provide accurate information. Most importantly, the findings reveal the students’ knowledge about (1) the role of an eventual process of vaccination, (2) the test currently used as diagnostic for Covid-19, and (3) the fatality rate, three aspects of Covid-19 literacy that deserve more attention. The findings provide a useful basis for the formulation of policies and concrete actions in improving Covid-19 literacy.

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10.
The current study presents results from students' engagement of composing print essays and composing across modes on the same topic. It builds on the premise that print‐based reading and writing should complement and coexist with multimodal pedagogy. A group of Taiwanese adolescent students were invited to complete one print essay and one multimodal product on the same topic of “My favorite place in the world”. For their multimodal product, students were required to use at least two modes (e.g. words and image, sounds and words) in any medium (e.g. video, collage, scrapbook or website) of their choice. It was found that the most frequently used medium for students' multimodal projects was video which incorporated words, sounds and visuals. Most students felt that for the topic of “My favorite place in the world”, their multimodal products helped them to convey their ideas better because they provided the audience with more sensory information. To conclude the paper, a few future research directions are outlined to help move the research of multimodal composing forward.  相似文献   
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