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81.
The adjustments and diagnostic significance of polyacrylamide gel electrophoretic (PAGE) profiles of lactate dehydrogenase isoenzymes (LDH: 1.1.1.27) was evaluated in the sera and pleural fluid of patients with tubercular pyothorax. Sera and pleural fluid samples were randomly collected from 72 and 18 patients respectively at two different timings; first, when patients were admitted to the Hospital and second, after an intensive phase of treatment. Sera of 20 healthy individuals served as control. Our results demonstrate significant differences in sera LDH (sLDH) and pleural fluid LDH (pfLDH) isoenzymes. In patients the order of LDH isoenzyme in sera and pleural fluid followed: LDH−5>−4>−2>−3>−1 and LDH-5>−4>−3>−2>−1 respectively. The ranking of activity levels in control was LDH−2>−1>−3>−5>−4. In the second phase of sampling from 31 patients, values of sLDH isoenzymes showed recovery and resembled profiles of controls. Therefore, the sLDH zymograms of patients can be used as the prognostic marker, since they tend to reach the normal level during recovery signifying the effect of chemotherapy in hospitalized patients. Moreover, according to the present findings on LDH-PAGE profiles, the levels of LDH-5 and-4 rise in pyothorax patients significantly (P<0.05). This elevation along with the rise in total LDH activity may, therefore, be used in the diagnosis and monitoring of tubercular pyothorax.  相似文献   
82.
1IntroductionThePadéapproximationisatypeofrationalfractionapproximationtoafunction.Letfberepresentedbyapowerseriesf(x)=∑∞i=0c...  相似文献   
83.
The aim of this study was to develop a coding scheme rooted in the Knowledge Building model, named Conversational Functions for Knowledge Building (CF4KB), to analyze students’ interactions in an online undergraduate course. In order to develop the coding scheme, we analyzed students discourse and identified the kinds of “Conversational Functions” students performed. Connecting these identified functions with Knowledge Building Model principles, we developed the coding scheme to analyze knowledge building [In the present article, we used “Knowledge Building” to indicate the theoretical model and “knowledge building” to refer to the activity of the community members.] activity. Applying the resulting coding scheme, two independent judges coded 186 messages posted into Knowledge Forum by 26 students (5 men and 21 women) attending the online course of Educational Psychology at University of Valle d’Aosta to develop the coding scheme. The inter-coder agreements obtained were 77.3 and 78.0%, with Cohen’s K?=?0.68 and 0.66, respectively for Specific and Global Conversational Functions level. The theoretical implications and possible uses in different contexts for future inquiry of this instrument are discussed.  相似文献   
84.
The purpose of this study was to investigate the efficacy of a preventive counseling program for improving psychological hardiness (PsyH) and the positive use of social network sites (SNSs). The sample consisted of 30 students from Mu’tah University in Jordan who were randomly assigned into either an experimental group (15) or a control group (15). Two constructed scales - the PsyH scale and the Positive Use of SNSs scale - were administered to both groups pre-test and post-test, and a one-month follow-up measure was also administered to the experimental group. The findings revealed that the preventive counseling program significantly improved the level of PsyH and the positive use of SNSs and seemed to have sustained efficacy.  相似文献   
85.
This paper presents the systematic development of a ‘Uses and Gratification Expectancy’ (UGE) conceptual framework which is able to predict students’ ‘Perceived e-Learning Experience. ’ It is argued that students’ UGE as regards e-learning resources cannot be implicitly or explicitly explored without first examining underlying communication theories and learning perspectives. As such, the theoretical framework is grounded in the confluence of theories from communication theories and learning perspectives. The integration of Expectancy-value Theory, and the Uses and Gratification Theory serves to accommodate the suggestion that elearning resources offer gratifications that are expected and valued by students. The key theoretical and practical assumptions of the UGE approach are highlighted and consistently implemented in the conceptual edifice.  相似文献   
86.
A socioscientific issues integrated instruction was used in the study to resolve college students attitude towards sexually-themed science content. Some 200 college students participated in the study as experimental and control groups. The former consisting of 98 students from one college was taught the content using the socioscientific issues integrated instruction. The later with 102 students from another college was taught the same content using a traditionally teacher dominated lectures. Both groups were taught over a period of eight weeks. Qualitative and quantitative data were obtained before and after the intervention. The quantitative data were analysed using analysis of covariance. The results revealed that there was a significant difference between the experimental and the control groups (F (1, 247) = 426.97, p = .00, partial eta squared = 0.64) where the experimental group showed a significant change in attitude towards the content studied. The qualitative data obtained some experimental group students showed a change in attitude the second interview. It was concluded that the use of the approach has significantly made the college students feel comfortable and confident to learn and teach the content.  相似文献   
87.
Classroom     
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science.  相似文献   
88.
For most open universities,in fact for most universities,there will arise occasions when some online activities will have to be completed by all students in a very short time interval.These occasions usually result in a great rush to get online as quickly as possible;the rush is often made worst by the limited good choices on offer such that usually only the earliest can get the best.Choosing and confirming elective subjects,when only a limited number for each are offered,on a first-come-first-served basis is an example. At the Open University Malaysia the rush occurs when confirming offered subjects and choosing face-to-face meeting timetable.Most students rushed to be earliest to ensure choice slots in the timetable are obtained. Available I.T.resources such as Internet bandwidth and servers cannot cope with these short-term sustained peak demands.Unless these peak demands are met,however,online services will slow down drastically resulting in long queues of users waiting to be served.Providing excess capacity,if at all possible,to ensure these short duration peak demands can be met would not be cost-effective since most of the time these resources are not utilised.This paper will look at some cost-effective approaches to meeting these short-term peak demands.  相似文献   
89.
90.
Experimental studies on the head fake in basketball showed that participant’s responses in a pass direction identification task were delayed for incongruent compared to congruent directions of the players gaze and pass (so-called head fake effect). In these studies on the head fake effect, static pictures were presented and responses on the pass direction were given with a simple key press. The present study examines whether an increase in the response complexity affects the head fake effect and whether it can also be transferred to the presentation of dynamic stimuli. In experiment 1, participants were presented with static pictures of a basketball player who passes a ball to the left or to the right. The player’s gaze direction was either oriented in the direction of the intended pass or in the opposite direction (i.?e., a head fake). The participants were asked to respond as quickly as possible to the pass direction and to ignore the gaze direction. Participants gave responses by pressing a key (simple response) or by executing a quasirealistic defense movement (complex response). Response complexity was blocked. In experiment 2, videos replaced the static stimuli. The responses were only given with the complex, full body movement. Results show that the head fake effect is independent of response complexity and that it can also be found when presenting dynamic stimuli.  相似文献   
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