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931.
BURKE AND THE NATURE OF POLITICS: THE AGE OF THE AMERICAN REVOLUTION. By Carl B. Cone. Lexington: University of Kentucky Press, 1957; pp. xvi+415. $9.00.

THE CORRESPONDENCE OF EDMUND BURKE (Volume I, April 1744—June 1768). Edited by Thomas W. Copeland. Cambridge: The University Press and Chicago: University of Chicago Press, 1958; pp. xxvi+377. $8.00.

A CHECKLIST OF THE CORRESPONDENCE OF EDMUND BURKE. By Thomas W. Copeland and Milton Shumway Smith. Cambridge: The University Press for the Index Society, 1955; pp. xvíii+481. No list price.

A NOTE‐BOOK OF EDMUND BURKE. Edited by H. V. F. Somerset. Cambridge: The University Press, 1957; pp. xii+120. $3.50.

THE MORAL BASIS OF BURKE'S POLITICAL THOUGHT: AN ESSAY. By Charles Parkin. Cambridge: The University Press. 1956; pp. viii+145. $2.50.

EDMUND BURKE AND THE NATURAL LAW. By Peter J. Stanlis. Ann Arbor: University of Michigan Press, 1958; pp. xv+311. $5.75.

A PHILOSOPHICAL INQUIRY INTO THE ORIGIN OF OUR IDEAS OF THE SUBLIME AND BEAUTIFUL. By Edmund Burke. Edited with an Introduction and Notes by J. T. Boulton. London: Routledge and Kegan Paul and New York: Columbia University Press, 1958; pp. cxxx+197. $5.00.

EDMUND BURKE. By T. E. Utley. (Writers and Their Work: No. 87.) Lendon: Longmans, Green for The British Book Council and the National Book League, 1957; pp. 36. Two shillings.

REFLECTIONS ON THE REVOLUTION IN FRANCE. By Edmund Burke. Edited with an Introduction by Thomas H. D. Mahoney and an Analysis by Oskar Piest. (The Library of Liberal Arts, No. 46.) New York: Liberal Arts Press, 1955; pp. xliv+307. Paper $1.25, cloth $2.50.  相似文献   
932.
This study discusses the representation of (the) literacy (myth) in popular movies and a teaching and research project on cinematic literacy narratives. It attempts to reveal the existence of a powerful ‘Pygmalion template’ in contemporary movie culture. Focusing on a discourse or culture clash ‘Pygmalion movies’ simultaneously contribute to the discursive construction and deconstruction of the literacy myth. Because of their polysemic character, these films offer fertile grounds for inquiring into the problematic nature of literacy acquisition and discourse or culture clashes. Inviting pre‐service teachers to reflect on these issues, the authors created a curriculum as contact zone in which films are used as a primary source of knowledge and insight together with students’ movie analyses and interpretations, personal narratives, and theoretical readings. This exploratory study of on‐line discussion groups revealed the students’ contradictory and competing movie readings. Organizing the curriculum as a contact zone deepened the students’ and one’s own understanding of literacy as an ideological site of struggle in (movie) culture.  相似文献   
933.
Detection of proteins and nucleic acids is dominantly performed using optical fluorescence based techniques, which are more costly and timely than electrical detection due to the need for expensive and bulky optical equipment and the process of fluorescent tagging. In this paper, we discuss our study of the electrical properties of nucleic acids and proteins at the nanoscale using a nanoelectronic probe we have developed, which we refer to as the Nanoneedle biosensor. The nanoneedle consists of four thin film layers: a conductive layer at the bottom acting as an electrode, an oxide layer on top, and another conductive layer on top of that, with a protective oxide above. The presence of proteins and nucleic acids near the tip results in a decrease in impedance across the sensing electrodes. There are three basic mechanisms behind the electrical response of DNA and protein molecules in solution under an applied alternating electrical field. The first change stems from modulation of the relative permittivity at the interface. The second mechanism is the formation and relaxation of the induced dipole moment. The third mechanism is the tunneling of electrons through the biomolecules. The results presented in this paper can be extended to develop low cost point-of-care diagnostic assays for the clinical setting.  相似文献   
934.
Abstract

Both radiant and forced convective heat flow were measured for a prototype rowing headgear and white and black cotton caps. The measurements were performed on a thermal manikin headform at a wind speed of 4.0 m · s?1 (s = 0.1) in a climate chamber at 22.0°C (s = 0.05), with and without radiant heat flow from a heat lamp, coming from either directly above (90°) or from above at an angle of 55°. The effects of hair were studied by repeating selected measurements with a wig. All headgear reduced the radiant heat gain compared with the nude headform: about 80% for the caps and 95% for the prototype rowing headgear (P < 0.01). Forced convective heat loss was reduced more by the caps (36%) than by the prototype rowing headgear (9%) (P < 0.01). The radiant heat gain contributed maximally 13% to the net heat transfer, with or without headgear, showing that forced convective heat loss is the dominant heat transfer parameter under the chosen conditions. The results of the headgear – wig combinations were qualitatively similar, with lower absolute heat transfer.  相似文献   
935.
In the light of the intensity coupling effects reported in the literature, subjects' capacities for independently controlling the absolute velocity of their movement at the point of interception was evaluated by asking them to learn to propel orthogonally approaching balls, varying in their speed of approach, into target boxes placed at various distances from the interception point. As required for successful accomplishment of the task, movement velocity was found to be adapted to the distance to be covered, with the near target giving rise to lower velocities and the far target giving rise to higher velocities even when the conditions were presented in random order. Nevertheless, even though target distance accounted for a substantial proportion of the total variance, a small but significant effect of ball approach speed on movement velocity was found, suggesting that intensity coupling is a persistent but modulable phenomenon in interception tasks.  相似文献   
936.
937.
Purpose

The aim of this study was to test the hypothesized structural paths in Bandura's social-cognitive theory (SCT) model on adolescent girls' physical activity following a 12-month physical activity and dietary intervention to prevent obesity.

Method

We conducted a 12-month follow-up study of 235 adolescent girls (M age = 13.2 years, SD = 0.4) from 12 secondary schools located in low-income communities. At baseline, participants completed SCT scales related to physical activity (i.e., self-efficacy, intention, parental support, and outcome expectations). At baseline and 12-month follow-up (postintervention), participants wore accelerometers for 7 days. Structural equation modeling was used to determine if Time 1 measures predicted physical activity at 12-month follow-up after adjusting for baseline activity.

Results

The model explained 28% and 34% of the variance in physical activity and intention, respectively. Model fit indexes indicated the data were a good fit to the model; however, only self-efficacy was associated with physical activity at 12 months. There was no support for intention or outcome expectations as proximal determinants of behavior. Self-efficacy was associated with outcome expectations and parental support; however, only outcome expectations predicted intention.

Conclusions

Current findings indicate a large proportion of the variance for physical activity and intention remains unexplained and that the proposed pathways in the SCT model were not fully supported. Future model testing may need to consider augmentation or integration of theoretical models, which may include ecological components if we are to advance our understanding of physical activity behavior in this subgroup of the adolescent population.  相似文献   
938.
This study was designed to develop the Questionnaire Assessing School Physical Activity Environment (Q--SPACE) based on student perceptions. Twenty-eight items rated on 4-point Likert scales were administered to 244 middle school students in 9 schools. Exploratory factor analysis was used to evaluate the underlying structure of the items and 2 factors were extracted: physical environment (PE) and social environment (SE). Twelve and 8 items loaded saliently on PE (e.g., gym classes available) and SE (e.g., teacher encouragement), respectively. Factor scales had alpha coefficients of .86 (PE) and .81 (SE). One-week test–retest reliabilities for the factor scales of PE and SE were .78 and .72, respectively. Differences in PE scale scores across schools and PE and SE scale scores across student school physical activity behavior (e.g., participation on school teams) provided some evidence of scale construct validity. Overall, Q–SPACE demonstrates acceptable reliability for capturing middle school students' perceptions of school physical activity environment. The factorial validity needs to be assessed with confirmatory factor analysis and invariance testing procedures.  相似文献   
939.
Through a series of structured interviews, university librarians at six institutions provided their perspectives on innovation in academic libraries. The literature on leadership styles and organizational change provides insight into the roles of these leaders in the innovation process. Leadership was cited by many researchers as being a critical factor for organizations to innovate. University librarians revealed a commitment to innovation, some distinctively nontraditional innovations, and a concern for how to encourage risk-taking behavior. Further insight into the innovation process was sought by interpreting the interview data within a larger theoretical context. Although leadership and management can foster innovation in a library, researchers have reported other factors that can influence the ability to innovate, including organizational aspects – size and complexity – and environmental factors. Beyond the organizational aspects, the individual and the norms of the profession appear to create a framework with certain boundaries, some of which may impact the ability to innovate.  相似文献   
940.
Isolation and enumeration of circulating tumor cells (CTCs) are used to monitor metastatic disease progression and guide cancer therapy. However, currently available technologies are limited to cells expressing specific cell surface markers, such as epithelial cell adhesion molecule (EpCAM) or have limited specificity because they are based on cell size alone. We developed a device, ApoStream that overcomes these limitations by exploiting differences in the biophysical characteristics between cancer cells and normal, healthy blood cells to capture CTCs using dielectrophoretic technology in a microfluidic flow chamber. Further, the system overcomes throughput limitations by operating in continuous mode for efficient isolation and enrichment of CTCs from blood. The performance of the device was optimized using a design of experiment approach for key operating parameters such as frequency, voltage and flow rates, and buffer formulations. Cell spiking studies were conducted using SKOV3 or MDA-MB-231 cell lines that have a high and low expression level of EpCAM, respectively, to demonstrate linearity and precision of recovery independent of EpCAM receptor levels. The average recovery of SKOV3 and MDA-MB-231 cancer cells spiked into approximately 12 × 106 peripheral blood mononuclear cells obtained from 7.5 ml normal human donor blood was 75.4% ± 3.1% (n = 12) and 71.2% ± 1.6% (n = 6), respectively. The intra-day and inter-day precision coefficients of variation of the device were both less than 3%. Linear regression analysis yielded a correlation coefficient (R2) of more than 0.99 for a spiking range of 4–2600 cells. The viability of MDA-MB-231 cancer cells captured with ApoStream was greater than 97.1% and there was no difference in cell growth up to 7 days in culture compared to controls. The ApoStream device demonstrated high precision and linearity of recovery of viable cancer cells independent of their EpCAM expression level. Isolation and enrichment of viable cancer cells from ApoStream enables molecular characterization of CTCs from a wide range of cancer types.  相似文献   
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