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111.
This investigation examined the oxidative stress (F2-Isoprostane; F2-IsoP) and inflammatory (interleukin-6; IL-6) responses to repeat-sprint training in hypoxia (RSH). Ten trained male team sport athletes performed 3(sets)*9(repetitions)*5?s cycling sprints in simulated altitude (3000?m) and sea-level conditions. Mean and peak sprint power output (MPO and PPO) were recorded, and blood samples were collected pre-exercise, and again at 8 and 60?min post-exercise. Both MPO and PPO were significantly reduced in hypoxia (compared to sea-level) in the second (MPO: 855?±?89 vs. 739?±?95?W, p?=?.006; PPO: 1024?±?114 vs. 895?±?112?W, p?=?.010) and third (MPO: 819?±?105 vs. 686?±?83?W, p?=?.008; PPO: 985?±?125 vs. 834?±?99?W, p?=?.008) sets, respectively. IL-6 was significantly increased from pre- to 1?h post-exercise in both hypoxia (0.7?±?0.2 vs. 2.4?±?1.4?pg/mL, p?=?.004) and sea-level conditions (0.7?±?0.2 vs. 1.6?±?0.3?pg/mL, p?d?=?0.80) suggesting higher IL-6 levels of post-hypoxia. F2-IsoP was significantly lower 1?h post-exercise in both the hypoxic (p?=?.005) and sea-level (p?=?.002) conditions, with no differences between trials. While hypoxia can impact on exercise intensity and may result in greater post-exercise inflammation, it appears to have little effect on oxidative stress. These results indicate that team sport organisations with ready access to hypoxic training facilities could confidently administer RSH without significantly increasing the post-exercise inflammatory or oxidative stress response.  相似文献   
112.
It has previously been shown that cyclists are unable to maintain a constant power output during cycle time-trials on hilly courses. The purpose of the present study is therefore to quantify these effects of power variation using a mathematical model of cycling performance. A hypothetical cyclist (body mass: 70?kg, bicycle mass: 10?kg) was studied using a mathematical model of cycling, which included the effects of acceleration. Performance was modelled over three hypothetical 40-km courses, comprising repeated 2.5-km sections of uphill and downhill with gradients of 1%, 3%, and 6%, respectively. Amplitude (5–15%) and distance (0.31–20.00?km) of variation were modelled over a range of mean power outputs (200–600?W) and compared to sustaining a constant power. Power variation was typically detrimental to performance; these effects were augmented as the amplitude of variation and severity of gradient increased. Varying power every 1.25?km was most detrimental to performance; at a mean power of 200?W, performance was impaired by 43.90?s (±15% variation, 6% gradient). However at the steepest gradients, the effect of power variation was relatively independent of the distance of variation. In contrast, varying power in parallel with changes in gradient improved performance by 188.89?s (±15% variation, 6% gradient) at 200?W. The present data demonstrate that during hilly time-trials, power variation that does not occur in parallel with changes in gradient is detrimental to performance, especially at steeper gradients. These adverse effects are substantially larger than those previously observed during flat, windless time-trials.  相似文献   
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114.
In recent years, theorizing regarding the role and importance of media entertainment in everyday life has garnered much serious attention by media effects scholars. The role of moral judgments, sanctions, and lack thereof are areas in which theoretical development has expanded. The present study examines narrative exposure, identification, and moral judgment as indicators of the degree to which individuals may morally disengage during mediated entertainment experiences. In addition, this study attempts to further expand disposition theory and theorizing about the role of moral disengagement by moving beyond conceptualizations of good, bad, and morally ambiguous characters to explore more subtle moral distinctions between characters as they exist within the same narrative and along a continuum. Results suggest that identification and moral judgment serve as important mediators predicting moral disengagement; however, the nature of these relationships are moderated by the perception of the character’s moral fortitude.  相似文献   
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116.
As state tests of student achievement are used for an increasingly wide array of high- and low-stakes purposes, evaluating their instructional sensitivity is essential. This article uses data from the Bill and Melinda Gates Foundation's Measures of Effective Project to examine the instructional sensitivity of 4 states' mathematics and English language arts assessments to 5 measures of pedagogical quality. The results indicate modest overall levels of sensitivity, with some state assessments insensitive to most or all measures of pedagogical quality. Furthermore, there are sometimes substantial differences across states in the sensitivity of their assessments. The article calls for more research on what makes state tests instructionally sensitive and cautions against the use of insensitive assessments for consequential decisions.  相似文献   
117.
The purpose of this study was to investigate whether a linear factor analytic method commonly used to investigate violation of the item response theory (IRT) unidimensionality assumption is sensitive to measurable curricular differences within a school district and to examine the possibility of differential item performance for groups of students receiving different instruction. For grades 3 and 6 in reading and mathematics, personnel from two midwestern school systems that regularly administer standardized achievement tests identified the formal textbook series used and provided ratings of test-instructional match for each school building (classroom). For both districts, the factor analysis results suggested no differences in percentages of variance for large first factors and relatively small second factors across ratings or series groups. The IRT analyses indicated little, if any, differential item performance for curricular subgroups. Thus, the impact of factors that might be related to curricular differences was judged to be minor.  相似文献   
118.
This investigation presents a framework for understanding and also to test the efficacy of Social Work intervention on the well being of the white collared employee (industrial employee) and his/her family. A comprehensive and intensive personal- family exploration was done to uncover the relatedness of seemingly disparate areas of the clients lives. A total of 80 executives (industrial employees) served as subjects. A baseline assessment was done using structured, standardized interview-schedules/questionnaires. The results of the study can be enumerated as follows: After the Social Work intervention, the executives in occupational profile, there were significant changes in Role perception, overload, role conflict, low status and poor peer relations. In coping strategies there was significant improvement in sub-scales like problem solving and unproductive coping. Significant reduction was noticed in their proneness to heart disease, depression, inadequate mental mastery, and perceived ill health. There was significant improvement in their family group support, and in their expressiveness, achievement, orientation, active-recreational and organizational characteristics.  相似文献   
119.
OBJECTIVE: The purpose of this study is to examine processing of facial emotions in a sample of maltreated children showing high rates of post-traumatic stress disorder (PTSD). Maltreatment during childhood has been associated independently with both atypical processing of emotion and the development of PTSD. However, research has provided little evidence indicating how high rates of PTSD might relate to maltreated children's processing of emotions. METHOD: Participants' reaction time and labeling of emotions were measured using a morphed facial emotion identification task. Participants included a diverse sample of maltreated children with and without PTSD and controls ranging in age from 8 to 15 years. Maltreated children had been removed from their homes and placed in state custody following experiences of maltreatment. Diagnoses of PTSD and other disorders were determined through combination of parent, child, and teacher reports. RESULTS: Maltreated children displayed faster reaction times than controls when labeling emotional facial expressions, and this result was most pronounced for fearful faces. Relative to children who were not maltreated, maltreated children both with and without PTSD showed enhanced response times when identifying fearful faces. There was no group difference in labeling of emotions when identifying different facial emotions. CONCLUSIONS: Maltreated children show heightened ability to identify fearful faces, evidenced by faster reaction times relative to controls. This association between maltreatment and atypical processing of emotion is independent of PTSD diagnosis.  相似文献   
120.
In striving to educate as many children as possible and with limited funds to build a separate special education infrastructure to cater to the needs of children with disabilities, inclusive education was officially adopted in 1997 by the Department of Education in the Philippines as a viable educational alternative. This article reports on the current state of affairs for including children with disabilities within regular schools in the Philippines. The ‘Silahis Centres’ (‘school within the school’ concept) is presented as a feasible model for implementing and promoting the inclusion of children with disabilities within regular schools throughout the Philippines. Other aspects related to inclusive education such as teacher education, policies as well as lessons learned so far from inclusion efforts and future challenges are also described.  相似文献   
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