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951.
952.

Two levels of training (100 vs. 500 trials) and two ages of rats (young and adult) were used in a developmental analysis of the relationship between response strength and the effects of punishment. The apparatus was a Y maze with three discriminably different arms. After 100 or 500 reinforced trials, subjects were shocked each time they responded in one arm. The recovery sessions followed the punishment session. Results from the punishment day indicated that: (a) young rats received a greater amount of shock, and (b) additional training increased the amount of shock received by the young but decreased it in the adults. The recovery data showed that: (a) the suppressive effects of punishment were greater for the adults than for the young, and (b) the recovery scores were not influenced by degree of overtraining. The Age by Overtraining interaction suggested that the relationship between response strength and punishment is age dependent. The age differences found with the amount-of-shock and recovery measures provided additional support for the position that younger rats are less competent than adult rats in inhibiting responses.

  相似文献   
953.

Objective

To evaluate the effect of anti-vascular endothelial growth factor (VEGF) on juxtafoveal choroidal neovascularization (CNV) secondary to multifocal choroiditis (MFC) and wet age-related macular degeneration (AMD). Methods: In this retrospective, comparative study, 20 unique eyes with CNV were divided into two groups: 10 patients affected by MFC and 10 patients diagnosed with wet AMD. They all received local intravitreal (IVT) injections of ranibizumab, with 6 months of follow-up. Retreatment injections were performed based on findings suggestive of active neovascularization.

Results

Significant improvements were observed in the juxtafoveal CNV lesions, and average central macular thickness decreased in both groups following the anti-VEGF therapy (P<0.05). The average number of injections used in MFC patients was 1.6, while three injections on average were used in wet AMD patients (Z=?2.844, P=0.009). Best-corrected visual acuity was significantly improved in MFC patients after anti-VEGF therapy (P<0.05), and there was no significant difference in wet AMD patients between before anti-VEGF therapy and 6 months later (P>0.05).

Conclusions

IVT ranibizumab resulted in good clinical outcomes for juxtafoveal CNV secondary to MFC and wet AMD, but the average number of injections used in MFC was fewer than that used in wet AMD over a 6-month observation period. Compared with the wet AMD group, visual acuity was obviously improved in the MFC group at 6 months.
  相似文献   
954.
In this paper, the effects of second-order difference-frequency wave forces on the global motion of an offshore wind turbine system with a large displacement under the survival condition are studied. In this case, the hydrodynamic force is the main force because the blades are feathered to reduce the lifting force. The first-order hydrodynamic forces are calculated by WADAM, while the second-order wave forces are calculated by a customized MATLAB module. Then the hydrodynamic coefficients are transferred to the wind turbine analytical code FAST. Through the comparisons of dynamic responses between the first- and second-order numerical models, it is found that the second-order wave forces significantly influence the motion of floating wind turbine under the survival condition. Moreover, neglecting the second-order force significantly underestimates the tension forces in the mooring lines.  相似文献   
955.
Differential Grading Standards Revisited   总被引:2,自引:0,他引:2  
The differential grading standards described by Goldman and Widawski (1976) exist in the same magnitude and in roughly the same order a decade later in a different kind of institution. Major fields that attract as majors students who score higher on SATs employ stricter grading standards. These differential grading standards serve to attenuate the correlation between SAT scores and grades, which is, even in highly selective institutions, substantial.  相似文献   
956.
957.
In this paper, we propose a theoretical framework for designing on-line situated assessment tools for multimedia instructional systems. Based on an ecological psychology approach to situated learning, a graph theoretic methodology is applied to monitor students' performance (solution paths) throughout the learning activity. Deviation of the student's path from the target (expert) path generates indicators which can function as alerts to the student and to the instructor. The information collected in the dribble files and presented visually enables the instructor to identify problems quickly and intervene appropriately. The feasibility of the methodology is explored in case studies describing three instructional systems that teach (1) critical thinking and problem-solving skills, (2) principles of hemodynamic monitoring and treatment, and (3) orthodontic treatment, respectively.  相似文献   
958.
OBJECTIVE: Assessing the risk of further offending behavior by adult sexual perpetrators of children is highly relevant and important to professionals involved in child protection. Recent progress in assessing risk in sexual offenders has established the validity of actuarial measures, although there continues to be some debate about the application of these instruments. This paper summarizes the debate between clinical and actuarial approaches and reviews the "base rate" for United Kingdom sexual offense reconviction. METHOD: A review of the literature revealed 16 UK sexual reconviction studies, 8 using incarcerated samples (N=5,915) and 8 using non-incarcerated samples (N=1,274). UK estimates of sexual reconviction rates are compared with European and North American studies. RESULTS: The mean sexual reconviction rates for the incarcerated sample at 2 years (6.0%), 4 years (7.8%) and 6 years or more (19.5%) were higher than that of the comparative non-incarcerated sample at 2 years (5.7%), up to 4 years (5.9%), and 6 years or more (15.5%). The overall sexual reconviction rate for both samples combined was 5.8% at 2 years, and 17.5% at 6 years or more. CONCLUSIONS: The sexual reconviction rate for incarcerated sexual offenders is higher than that of non-incarcerated sexual offenders. The UK sexual reconviction rates were comparable with European and North American studies.  相似文献   
959.
The relation is studied between teachers’ pedagogical content knowledge of reading and the quality of their subsequent classroom behaviour in teaching fluent reading. A confirmatory factor analysis model with two latent variables is tested and shows adequate goodness-of-fit indices. Contrary to our expectations, the results of structural equation modelling reveal a small but significant γ-value of .29, indicating that only 8% of the variance in teachers’ classroom behaviour in teaching fluent reading is accounted for by teachers’ pedagogical content knowledge of reading. Presumably teacher knowledge is not as stable and conclusive as one might think. More research is needed in determining the factors that work restricting for teachers in putting their knowledge into classroom practice. It is recommended that preservice and in-service teacher training should not be limited to transfer of knowledge, but should also assist teachers in designing and performing effective fluent reading instruction.  相似文献   
960.
To increase the teacher efficacy of student teachers, they need positive classroom experiences: mastery experiences. These mastery experiences have to be created by the student teachers themselves. Therefore, student teachers need a tool to better understand problematic teaching experiences and help them create positive classroom experiences. Nine student biology teachers used this attribution support tool when reflecting on multiple lessons taught in classes they considered difficult. They scored their lessons and filled in a teacher efficacy questionnaire after each lesson. The results show that teacher efficacy increased and the number of failures during the lessons decreased; on average, the self-awarded marks per teacher per lesson increased, indicating an increase in mastery experiences. Therefore, the attribution tool seems to be a promising tool for student teachers to enhance their teacher efficacy and to support reflection on problematic teaching experiences.  相似文献   
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