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221.

Introduction

Postmenopausal women have higher risk of cardiovascular disease. One of the contributing factors could be reduced activity of anti-atherogenic enzyme paraoxonase 1 (PON1). The aim of this study was to examine differences in the lipid status, paraoxonase and arylesterase PON1 activities and PON1 phenotype in women with regular menstrual cycle and in postmenopausal women.

Materials and methods:

The study included 51 women in reproductive age (25 in follicular and 26 in luteal phase of the menstrual cycle) and 23 women in postmenopause. Lipid parameters in sera were determined using original reagents and according to manufacturer protocol. PON1 activity in serum was assessed by spectrophotometric method with substrates: paraoxon and phenylacetate. PON1 phenotype was determined by double substrate method.

Results:

Compared to the women in follicular and luteal phase, postmenopausal women have significantly higher concentration of triglyceride [0.9 (0.7–1.3), 0.7 (0.6–1.0) vs. 1.5 (0.9–1.7) mmol/L; P = 0.002], cholesterol [5.10 (4.78–6.10), 5.05 (4.70–5.40) vs. 6.30 (5.73–7.23) mmol/L; P < 0.001], LDL [3.00 (2.56–3.63), 3.00 (2.70–3.70) vs. 3.90 (3.23–4.50) mmol/L; P < 0.001], and apolipoprotein B [0.88 (0.75–1.00), 0.79 (0.68–1.00) vs. 1.07 (0.90–1.24) mmol/L; P = 0.002]. PON1 basal [104 (66–260), 106 (63–250) vs. 93 (71–165) U/L; P = 0.847] and salt-stimulated paraoxonase activity [210 (131–462), 211 (120–442) vs. 180 (139–296) U/L; P = 0.857] as well as arylesterase activity [74 (63–82), 70 (54–91) vs. 70 (60–81) kU/L; P = 0.906] and PON1 phenotype (P = 0.810) were not different in the study groups.

Conclusion:

There are no differences in PON1 activity and PON1 phenotype between women with regular menstrual cycle and postmenopausal women.  相似文献   
222.
223.
Megabits     
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224.
The unique relation of language use (i.e., output) to language growth was investigated for forty‐seven 30‐month‐old Spanish–English bilingual children (27 girls, 20 boys) whose choices of which language to speak resulted in their levels of English output differing from their levels of English input. English expressive vocabularies and receptive language skills were assessed at 30, 36, and 42 months. Longitudinal multilevel modeling indicated an effect of output on expressive vocabulary growth only. The finding that output specifically benefits the development of expressive language skill has implications for understanding effects of language use on language skill in monolingual and bilingual development, and potentially, for understanding consequences of cultural differences in how much children are expected to talk in conversation with adults.  相似文献   
225.
Abstract

This paper explores LGBTIQ+ students’ experiences of knowing, performing and holding queerness in a tertiary educational environment. Through interviews conducted with LGBTIQ+ students at a large Australian metropolitan university, we examine the students’ engagement with other LGBTIQ+ students in the tertiary educational space. Although originally intending to explore LGBTIQ+ students’ experience of violence, harassment and abuse on campus, the study identified a number of themes concerning the normalisation of a set of beliefs, practices, presentations and performances. Drawing on frameworks of hetero/homo and trans-normativity, we explore how LGBTIQ+ students articulated concerns in knowing, performing and holding ‘authentic’ queerness. We find LGBTIQ students experienced barred access to knowledge, hostility and dismissal by other LGBTIQ+ students when they were either perceived as too queer, or not queer enough. Behind these interactions and at the heart of these tensions is the notion of an authentic queer identity in a post-gay era and the continuous challenges all LGBTIQ+ students face within a heteronormative society. New insights into how LGBTIQ+ students negotiate, manage and shape their interactions in a higher educational settings are provided, and the implications for tertiary educational institutions, in particular the need to support a diverse LGBTIQ+ community, are discussed.  相似文献   
226.
College students respond to stressful experiences along a continuum of distress and suicidality. This study investigated, from students’ perspectives, the contributors to stress, nature of stress, coping strategies used, and role of drugs and alcohol during stressful periods—all with particular relevance for suicidality. Undergraduate and graduate students were sampled on an online survey from 73 institutions, totaling 26,292 respondents. The pervasiveness of stressful experiences students endorse appears to be more than traditional clinical interventions can manage on their own. Recommendations are, therefore, made about how to utilize population-based prevention to reduce students’ distress and suicidality and improve their mental health.  相似文献   
227.
It has been seven years since the Early Years Learning Framework (EYLF) was introduced in Australia and four years since the National Quality Standard (NQS) was implemented. To gain insight into how educators are understanding practice in the Australian early childhood and care context, the study draws on a praxeological frame where educators have the opportunity to inquire and critically reflect on practice in a supported research environment. Data were analysed using critical discourse analysis, enabling a close examination of participant reflections and understandings about practice. Findings reveal that educators are confident when describing their teaching using familiar educational discourse, whereas educators were apprehensive when confronted with new and unfamiliar concepts. The third finding illustrates the ways educators gain confidence with unfamiliar policy discourse. The study’s findings add to limited empirical evidence about how early childhood educators understand key concepts introduced by the EYLF and NQS.  相似文献   
228.
Though their fur is black and white,those are notthe only colors that giant pandas see.A new study finds two zoo pandas,Lun Lun andYang Yang,were able to distinguish colors from shadesof gray.Though color vision is well studied in domesticatedanimals,like…  相似文献   
229.
ABSTRACT

In order to increase student commitment from the beginning of students’ university careers, the Technische Universität Darmstadt has introduced interdisciplinary study projects involving first-year students from the engineering, natural, social and history, economics and/or human sciences departments. The didactic concept includes sophisticated task design, individual responsibility and a differentiated support system. Using a self-determination theory framework, this study examined the effects of the projects based on survey findings from two projects with more than 1000 students. The results showed that the projects were successful in fulfilling students’ basic psychological needs and in promoting students’ academic engagement. Basic psychological needs were found to be significant predictors of academic engagement. These findings suggest that interdisciplinary study projects can potentially contribute to improving higher education as they fulfil students’ basic psychological needs for competence, relatedness and autonomy and enhance students’ academic engagement.  相似文献   
230.
There is a current national emphasis on science, technology, engineering, and mathematics (STEM). Additionally, many states are transitioning to the Next Generation Science Standards (NGSS), which encourage teachers to incorporate engineering in science classrooms as well as have their students learn science by doing science. Methods courses are also shifting to adequately prepare preservice science teachers in these areas. This study examines preservice science teachers’ pre- and post-ideal inquiry-based lesson plan scenarios before and after intervention in their Secondary Science Methods I and II courses. These preservice science teachers participated in a variety of opportunities to practice authentic science inquiry (ASI) pedagogical techniques as well as integrated STEM topics, with a particular emphasis on computer programming throughout their 80 h of Methods instruction. ASI is a type of inquiry where students learn science by conducting science research in a grade-appropriate manner. Thirty-eight preservice teachers’ scenarios were analyzed using a rubric from Spuck (2014) to determine the degree to which the ten components of ASI were included in scenarios pre- to post-instruction. Trends in ASI component inclusion are discussed. These findings indicate that preservice science teachers are proficient at writing inquiry-based lessons where they planned opportunities for their future students to collaborate, use scientific instrumentation, and collect and analyze data, but need additional support with developing student activities where students create testable questions, revise their question and methods, participate in peer review, and disseminate their results to their peers or the larger scientific community. Overall, the results suggest Methods instruction should reinforce preservice teachers’ focus on planning lessons which include opportunities for all ASI components. Interventions in the aforementioned areas of weak inclusion may be beneficial to preservice teachers.  相似文献   
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