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61.

Objective

Comparison of global end-diastolic volume index (GEDVI) obtained by femoral and jugular transpulmonary thermodilution (TPTD) indicator injections using the EV1000/VolumnView® device (Edwards Lifesciences, Irvine, USA).

Methods

In an 87-year-old woman with hypovolemic shock and equipped with both jugular and femoral vein access and monitored with the EV1000/VolumeView® device, we recorded 10 datasets, each comprising duplicate TPTD via femoral access and duplicate TPTD (20 ml cold saline) via jugular access.

Results

Mean femoral GEDVI ((674.6±52.3) ml/m2) was significantly higher than jugular GEDVI ((552.3±69.7) ml/m2), with P=0.003. Bland-Altman analysis demonstrated a bias of (+122±61) ml/m2, limits of agreement of ?16 and +260 ml/m2, and a percentage error of 22%. Use of the correction-formula recently suggested for the PiCCO® device significantly reduced bias and percentage error. Similarly, mean values of parameters derived from GEDVI such as pulmonary vascular permeability index (PVPI; 1.244±0.101 vs. 1.522±0.139; P<0.001) and global ejection fraction (GEF; (24.7±1.6)% vs. (28.1±1.8)%; P<0.001) were significantly different in the case of femoral compared to jugular indicator injection. Furthermore, the mean cardiac index derived from femoral indicator injection ((4.50±0.36) L/(min·m2)) was significantly higher (P=0.02) than that derived from jugular indicator injection ((4.12±0.44) L/(min·m2)), resulting in a bias of (+0.38±0.37) L/(min·m2) and a percentage error of 19.4%.

Conclusions

Femoral access for indicator injection results in markedly altered values provided by the EV1000/VolumeView®, particularly for GEDVI, PVPI, and GEF.
  相似文献   
62.
The AERA, APA, NCME Standards define validity as ‘the degree to which evidence and theory support the interpretations of test scores for proposed uses of tests’. A century of disagreement about validity does not mean that there has not been substantial progress. This consensus definition brings together interpretations and use so that it is one idea, not a sequence of steps. Just as test design is framed by a particular context of use, so too must validation research focus on the adequacy of tests for specific purposes. The consensus definition also carries forward major reforms in validity theory begun in the 1970s that rejected separate types of validity evidence for different types of tests, e.g. content validity for achievement tests and predictive correlations for employment tests. When the current definition refers to both ‘evidence and theory’ the Standards are requiring not just that a test be well designed based on theory but that evidence be collected to verify that the test device is working as intended. Having taught policy-makers, citizens, and the courts to use the word validity, especially in high-stakes applications, we cannot after the fact substitute a more limited, technical definition of validity. An official definition provides clarity even for those who disagree, because it serves as a touchstone and obliges them to acknowledge when they are departing from it.  相似文献   
63.
Argumentative thinking requires not only the skill to apply argumentative strategies such as supporting theories with evidence but also the will to apply these strategies by considering argumentative thinking to be both reasonable and worthwhile. Focusing on direct instruction for the initial acquisition of both skill and will, we developed a new short-term computer-based training intervention. We tested its effects on learning processes and learning outcomes in an experimental study with 147 German high school students. Our intervention fostered facets of both skill (i.e. a declarative knowledge about argumentation) and will (i.e., epistemic orientation, intellectual values, and epistemic knowledge). We gained additional insights into learning mechanisms, such as the mediating effects of the learners' self-explanation activities and the advantage of addressing will before skill.  相似文献   
64.
The present study aims to reveal the effects of positioning on decision-making performance in top-level refereeing in association football. To this end, for all 64 matches of the FIFA World Cup 2014, potential foul-play situations were videometrically analysed in terms of the referee’s position relative to the infringement. Contrary to earlier studies, viewing angles were analysed in addition to viewing distances and error rates were considered for not only falsely whistled but also falsely non-whistled events. Moreover, direct logistic regression analysis was applied to detect position-dependent differences. For the total of 1,527 potential foul play situations, an overall low error rate of 6.9% was found. The similar numbers of total whistle (n = 52) and non-whistle errors (n = 54) reflect referees’ ability to balance both types of errors. Regarding the overall viewing-distance effect, referees were 2.58 times (95% CI 1.47–4.54) more likely to commit a whistle error at 10–15 m and 5.51 times (95% CI 1.35–22.47) more likely to commit a non-whistle error at 0–5 m, corresponding to the position ranges occurring with the highest (10–15 m: 30.3%) and lowest (0–5 m: 5.8%) frequencies. In contrast, no significant effects of viewing-angle on decision-making accuracy could be revealed.  相似文献   
65.
The purpose of the study was to assess the effect of kindergarten retention on firstgrade achievement and adjustment. Forty children who had been retained in kindergarten were identified from schools that practiced kindergarten retention at a high rate. Control children were selected from schools matched on socioeconomic and achievement level, but that did not practice retention in kindergarten. Then, control children were selected individually to match retained children on sex, birthdate, socioeconomic level, second language, and beginning kindergarten readiness scores. The two groups, which were equally young and unready at the start of kindergarten, were compared at the end of first grade on seven outcome measures; the retained children were then completing three years of school and the control children two. There were no differences between the retained and control children on teacher ratings of reading achievement, math achievement, social maturity, learner self-concept, or attention. The groups also did not differ in CTBS math scores; the only difference occurred on the CTBS reading test, where the retained group was one month ahead. Based on parent interview data, children who had spent an extra year before first grade were not much different from those deemed at risk but not retained, except that, on average, retained children had slightly more negative attitudes toward school. The study findings are consistent with other available research on transition programs that show no academic benefit for the extra year and, when examined, a negative impact on social-emotional outcomes.  相似文献   
66.
Until recently, the physiological demands of cycling competitions were mostly reflected by the measurement of heart rate and the indirect estimation of exercise intensity. The purpose of this case study was to illustrate the varying power output of a professional cyclist during flat and mountain stages of a Grand Tour (Giro d'Italia). Nine stage recordings of a cyclist of the 2005 Giro d'Italia were monitored using a mobile power measurement device (SRM Trainingssystem, Julich, Germany), which recorded direct power output and heart rate. Stages were categorized into flat (n = 5) and mountain stages (n = 4). Data were processed electronically, and the overall mean power in flat and mountain stages and maximal mean power for various durations were calculated. Mean power output was 132 W +/- 26 (2.0 W x kg(-1) +/- 0.4) for the flat and 235 W +/- 10 (3.5 W x kg(-1) +/- 0.1) for the mountain stages. Mountain stages showed higher maximal mean power (367 W) for longer durations (1800 s) than flat stages (239 W). Flat stages are characterized by a large variability of power output with short bursts of high power and long periods with reduced intensity of exercise, whereas mountain stages mostly require submaximal, constant power output over longer periods.  相似文献   
67.
University students are too often challenged by their limited skills in application, investigation, relational thinking, and communication of ideas. In this study, we have combined 3 tools that potentially can support and foster students’ development in the above mentioned areas through student collaboration, concept mapping, and electronic technologies. The participants in this study were 26 students in two intact classes in learning theories. In groups of 3 to 5 students, they were asked to generate 3 concept maps and accompanying prose over the term on 3 major issues in the field of learning. Through the use of interviews, questionnaires, and student generated concept maps, students reportedly enjoyed concept mapping for its organizational and relational properties but preferred sharing their concept maps and dialoguing with one another in a synchronous mode where immediate feedback and flow of thinking could be maintained when involved in constructing maps. Moreover, they did not like the redundancy offered by both prose and concept map outputs, suggesting that while concept mapping can be an arena for generating and generally structuring ideas, prose can be a means of communicating such ideas in a form that is common to most people. This is particularly important for teachers and students who have difficulty navigating through maps alone.  相似文献   
68.
Research to date has demonstrated that networking can be an effective strategy for supporting meaningful learning. However, studies have shown that learners encounter difficulties using it. In an attempt to understand and thus reduce these difficulties, this study examined learners' underlying cognitive processes and activities while networking. Detailed process, observational, and post-activity interview data were gathered on 14 participants during and after their networking of an 800-word text. The study showed that learners must possess several forms of prior knowledge, and devote appropriate time and effort in order to derive benefits from networking. The instructional implications of the process and the methodological contribution of this study are discussed.  相似文献   
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