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11.

Introduction:

Two Italian adults arrived at the Emergency Department referring diarrhea, nausea and vomiting for 4 days; weakness, fatigue and visual hallucinations were also complained of. Patients reported the ingestion of some leaves of a plant, which they supposed to be “donkey ears”, a week before. Physical examination showed hypotension and bradycardia and ECG examination disclosed sinus rhythm and repolarization abnormalities (scooping of the ST-T complex) in both patients and a 2:1 AV block in the man.

Materials and methods:

Digoxin concentration was evaluated twice for each patient (at the admission and after 4 hours) by the automated immunoassay system ADVIA Centaur®. Digitoxin concentration was evaluated by liquid chromatography-mass spectrometry (LC-MS/MS).

Results:

Despite clinical picture was suggestive of digitalis intoxication, digoxin levels were undetectable. Due to the more severe clinical picture, the male patient was treated with anti-digoxin antibodies (Digifab®) achieving a good clinical improvement and remission of the AV block within two hours. Initial diagnosis was confirmed by LC-MS/MS showing high digitoxin concentrations, but digoxin was undetectable. Patients remained stable and 48 hours later were discharged from the hospital.

Conclusion:

Whereas digoxin determination frequently relies on monoclonal antibodies which do not cross-react to digitoxin, polyclonal antibodies constituting Digifab® recognize a large spectrum of cardiac glycosides, including digitoxin. This report emphasizes the primary role of the clinical approach to patients in the emergency setting and how an active communication and a continuous sharing of professional experiences between Laboratory and Clinicians ensure an early and correct diagnosis.  相似文献   
12.
13.
This contribution starts out from the assumption that participation in continuing professional education is realized in the context of different opportunity structures and an analysis of participation selectivity must take account of both self-selection and external selection processes. The different opportunity structures are described using approaches from segmentation and economic theory, which lead to the identification of three segments of continuing professional education. Participation structures in the three training segments are shown using logistic regressions, which take account of socio-demographic and individual characteristics of the social and employment environment. These predictors display segment-specific influences, which emphasizes the importance of differentiated perspectives on continuing professional education. Overall, participation is shown to be clearly influenced by external selection processes. The basis of the analyses is data from the German National Educational Panel Study (NEPS), cohort 2009/10.  相似文献   
14.
Modern OCR engines incorporate some form of error correction, typically based on dictionaries. However, there are still residual errors that decrease performance of natural language processing algorithms applied to OCR text. In this paper, we present a statistical learning model for post-processing OCR errors, either in a fully automatic manner or followed by minimal user interaction to further reduce error rate. Our model employs web-scale corpora and integrates a rich set of linguistic features. Through an interdependent learning pipeline, our model produces and continuously refines the error detection and suggestion of candidate corrections. Evaluated on a historical biology book with complex error patterns, our model outperforms various baseline methods in the automatic mode and shows an even greater advantage when involving minimal user interaction. Quantitative analysis of each computational step further suggests that our proposed model is well-suited for handling volatile and complex OCR error patterns, which are beyond the capabilities of error correction incorporated in OCR engines.  相似文献   
15.
In two experiments, saccharin (CS) and lithium chloride (US) were paired in a context consisting of specific visual, auditory, tactual, and olfactory cues. The saccharin aversion was then extinguished in a context free from conditioning-context cues. Later, saccharin preference tests were given in the presence and absence of these cues. The results indicated that the background cues of the conditioning trial controlled the amount of saccharin drunk on extinction trials, and, furthermore, that extinction of the taste aversion was context specific; i.e., groups given extinction trials in a different (from conditioning) context retained their saccharin aversion in the conditioning context only. The results indicate an important role played by the exteroceptive context in taste-aversion conditioning.  相似文献   
16.
Theorems are stated and proved that provide necessary and sufficient conditions for practical stability of discrete-time systems.The first part of the paper deals with stability and instability with respect to time-varying sets, whereas the second part is devoted to the study of final and semi-final stability. The conditions obtained, which take the form of existence of discrete Lyapunov-like functions, generalize previous results.  相似文献   
17.
Holder (1988) has raised several objections to our work on the role of exteroceptive contextual stimuli in taste-aversion learning by rats. Our main conclusion from that work is that tongue-tactile stimuli from the drinking spout constitute the likely basis for findings of contextual bottle control over learned taste aversions. Holder suggests that our results are confounded by taste cues from the fluid containers. We refute this suggestion by presenting data from two experiments showing contextual bottle control, even though potential taste cues from the drinking bottles were eliminated. We also point to the fact that some of Holder’s criticisms are based on misreadings of our various reports.  相似文献   
18.
This study examined linguistic recasts provided by 16 early childhood educators to preschool children learning English as a second language (EL2). Recasts are semantic and syntactic revisions of children’s utterances. The educator–child interactions were filmed during book reading and play dough activities with small groups of four children, one of whom was EL2. The EL2 children were rated by their educators as having less well-developed expressive language skills than their unilingual peers. However, despite this finding, educators provided similar rates of recasts to both groups of children. Eight EL2 children with the lowest expressive language skills demonstrated fewer uptakes of their educator’s recasts in comparison to EL2 children with higher expressive language skills. The implications of this study include increasing the rate of recasts and reducing their complexity to provide language-learning opportunities for all preschool children, especially for those learning English as a second language.  相似文献   
19.
Data from 36 groups of rats from a total of 12 taste-aversion (saccharin+lithium chloride) experiments were analyzed for (1) individual differences of absolute saccharin (sacc) intake on the first (conditioning) and second (test) presentations, and (2) the correlation between intakes on the two presentations. Large individual differences and strong positive correlations were found for sacc+LiCl, sacc+NaCl, sacc?LiCl unpaired, and “different context” conditions. In addition to raising doubts about the use of absolute saccharin intake as a measure of taste-aversion learning, these results support the view that an associative (taste-nausea) component is superimposed on a neophobic avoidance of the novel taste stimulus.  相似文献   
20.
Adventure training has become fashionable over the past few years in Hong Kong. Current Education Reform suggests learning should not be confined to the classroom, and adventure training is viewed as an alternative method to institutional routines for personal and group development. This paper reported a longitudinal study investigating how learning happened for four church members (out of twenty-five participants) purposively selected in an adventure team-building camp. Both quantitative and qualitative instruments were used. Results shed light on: (1) how the constructs of self-efficacy and organizational commitment helped to conceptualize what people meant by a team; (2) how qualitative findings revealed evidence of learning of the four members which could not be observed by quantitative findings; and (3) how participants experienced and learnt from adventure training.  相似文献   
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