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Purpose

The purpose of the present review was to use existing, published data to provide an estimate of the amount of change in six-minute walk test distance (Δ6MWT) that represents a clinically meaningful change in individuals with chronic heart failure (CHF).

Methods

The present review included two separate literature searches of the CINAHL and Medline databases for articles that: (1) reported the intraclass correlation coefficient (ICC) of the 6MWT in individuals with CHF, and (2) used the 6MWT along with either aerobic capacity or health-related quality of life (HRQL) as study endpoints in randomized controlled trials (RCTs) of exercise-based intervention for individuals with CHF. The ICCs were used to calculate the minimum detectable difference (MDD) at the 95% confidence interval for each included study. The Δ6MWT associated with aerobic capacity and HRQL within-group effect sizes for the intervention and control groups in each included RCT was analyzed using receiver operating characteristic (ROC) curves.

Results

Thirteen articles reported the ICC for the 6MWT. The mean (standard deviation) MDD calculated based on these data was 43.1(16.8) m. Eighteen RCTs measured the 6MWT and either aerobic capacity and/or HRQL. A Δ6MWT of 40–45 m was associated with at least moderate aerobic capacity and HRQL effect sizes in the intervention groups. The Δ6MWT thresholds that discriminated between intervention and control groups using ROC curves revealed the following sensitivity/specificity for the respective thresholds: 19 m, 94.4/83.3%, 32 m, 83.3/94.4%, and 48 m 44.4/100% (AUC = .935, p = .009, CI95% .855, 1.015).

Conclusions

A Δ6MWT of approximately 45 m appears to exceed measurement error and be associated with significant changes in either aerobic capacity and/or HRQL.Key Words: heart failure, six-minute walk test, clinically meaningful change, minimum detectable difference  相似文献   
45.
Research suggests that undergraduate students learn more from lab experiences that involve longer-term projects. We have developed a one-semester laboratory sequence aimed at sophomore-level undergraduates. In designing this curriculum, we focused on several educational objectives: 1) giving students a feel for the scientific research process, 2) introducing them to commonly used lab techniques, and 3) building skills in both data analysis and scientific writing. Over the course of the semester, students carry out two project-based lab experiences and write two substantial lab reports modeled on primary literature. Student assessment data indicate that this lab curriculum achieved these objectives. This article describes the first of these projects, which uses the biflagellate alga Chlamydomonas reinhardtii to introduce students to the study of flagellar motility, protein synthesis, microtubule polymerization, organelle assembly, and protein isolation and characterization.  相似文献   
46.
Shoemaker RW 《Endeavour》2001,25(2):61-67
Over half a century ago, when I took Beginning Physics at university, I was bothered by the anomaly that normal air pressure (which is arbitrary anyhow) was taken to be 1.013250 bar instead of a sensible 1.000000 bar. My professor could not explain why, nor could any of the many other scientists whom I have asked since then. Now in retirement, I have made a laborious search in utterly uncharted territory and discovered the answer.  相似文献   
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In this paper, I critically examine the discourse surrounding response to intervention (RTI), a US-based education reform that has garnered a considerable amount of attention (as well as controversy) in a very short amount of time. A multi-pronged reform effort, RTI is a tiered approach to delivering instructional intervention to students at risk, an on-going and systematic model of monitoring student performance, as well as an alternative to the ability/achievement discrepancy model for identifying learning disabilities. In this paper, I argue, however, that RTI is not so much a reform but a tactic, aimed at returning to the status quo of segregated special education and reinvigorating many of the foundational assumptions of traditional special education practice.  相似文献   
48.
Higher educational institutions place a priority on the retention and timely graduation of students. Previous literature has identified transfer students to have unique concerns and that these concerns vary by major. While previous retention research has reported factors that influence students’ decision to remain in college, many of these studies treated transfer status as a homogenous group. The university in this study enrolls a high percentage of transfer students, and a large percentage of these transfers students enroll in Criminal Justice classes and become Criminal Justice majors. To determine if there are unique risk factors among Criminal Justice transfer students, this study uses multiple measures of transfer status to identify factors that might impact a students’ (1) university involvement, (2) GPA, (3) satisfaction with and sense of belonging to their university and (4) thereby influence their decision to remain in school. The proposition that transfer students as compared to native (nontransfer) students differ on how they face university challenges was also examined. While several variables were found to be important to students’ adjustment to the University, transfer status does not appear to be significant risk factor. Implications of the results are discussed.  相似文献   
49.
U.S. Supreme Court Justice Thurgood Marshall once argued that informed opinion would oppose the death penalty for all but those who support it for retributive reasons. We examine the validity of these claims with data from a series of one‐group pre‐test–post‐test designs which stem from a formalized learning outcomes assessment for several courses on the death penalty. Results show solid, but imperfect, support for these claims. The analysis then proceeds by profiling those who changed their opinions consistent with these claims, those who did not change their opinions, and those whose opinions changed in a manner opposite to these claims.  相似文献   
50.
Over the past several decades, there has been a wealth of research identifying factors and conditions of persistence toward graduation for first-year students and more recently transfer students. While previous research recognizes these critical periods, some recent literature suggests that students may face a similar transitional period later in their academic careers as they advance into their major areas of study. To date, there has been a dearth of information exploring upper-level students' success and commitment to graduation. Exploring this later transition might provide a critical link to understanding the graduation gap between those students who persist to graduation and those who drop out. The purpose of this research was to review the intervention programs proscribed by the literature, design an intervention program, and examine the impact of the program on criminal justice students during this advanced transitional phase of their college careers. It examined the direct and indirect effects of the intervention program on both retention and the antecedents of successful retention while controlling for other relevant influences identified in the literature. The results indicated that the intervention had small, but significant positive direct and indirect effects on academic integration, commitment to the university, and graduating in a timely fashion. Policy implications are discussed.  相似文献   
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