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941.
Technological agglomeration and the emergence of clusters and networks in nanotechnology 总被引:3,自引:0,他引:3
Research and development at the nanoscale requires a large degree of integration, from convergence of research disciplines in new fields of enquiry to new linkages between start-ups, regional actors and research facilities. Based on the analysis of two clusters in nanotechnologies (MESA+ (Twente) and other centres in The Netherlands and Minatec in Grenoble in France), the paper discusses the phenomenon of technological agglomeration: co-located scientific and technological fields associated to coordinated technology platforms to some extent actively shaped by institutional entrepreneurs. Such co-location and coordination are probably a pre-requisite for the emergence of strong nanoclusters. 相似文献
942.
R. Kumar S. B. Pachori G. K. Senger Satyanand L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1994,9(2):72-74
Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial
effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown
a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was
observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic
arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis
specially tubercular in initial stages. 相似文献
943.
A. K. Pradhan A. K. Shukla M. V. R. Reddy N. Garg 《Indian journal of clinical biochemistry : IJCB》2004,19(1):83-87
Oxidative stress was assesed by estimating lipid peroxidation product (LPO) in the form of thiobarbituric acid reactive substances
(TBARS), enzymatic antioxidants in the form of superoxide dismutase (SOD), catalase and nonenzymatic antioxidant vitamins
e.g. vitamin C, β carotene and vitamin E in either serum or plasma or erythrocytes in 190 cases of age related cataract in
the age group of 50–80 years. 190 cases were grouped into three morphological types namely, 73 cases of cortical, 77 cases
of posterior subcapsular and 40 cases of nuclear cataract and values of LPO and antioxidants were compared with 78 cases of
age matched healthy control groups. Plasma TBARS levels were cataract cases when compared with control groups. There were
no significant differences in the erythrocyte levels of catalase and plasma levels of Vit E between cataract cases and control
groups. No significant changes of parameters were seen among three different morphological types of age related cataract.
The present study shows that the oxidative stress may play an important role in the age related cataract. 相似文献
944.
945.
946.
Are preservice teachers prepared to teach struggling readers? 总被引:1,自引:0,他引:1
Reading disabilities such as dyslexia, a specific learning disability that affects an individual’s ability to process written
language, are estimated to affect 15–20% of the general population. Consequently, elementary school teachers encounter students
who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. However,
recent evidence may suggest that teacher preparation programs are not providing preservice teachers with information about
basic language constructs and other components related to scientifically based reading instruction. As a consequence preservice
teachers have not exhibited explicit knowledge of such concepts in previous studies. Few studies have sought to assess preservice
teachers’ knowledge about dyslexia in conjunction with knowledge of basic language concepts. The purpose of the present study
was to examine elementary school preservice teachers’ knowledge of basic language constructs and their perceptions and knowledge
about dyslexia. Findings from the present study suggest that preservice teachers, on average, are able to display implicit
skills related to certain basic language constructs (i.e., syllable counting), but fail to demonstrate explicit knowledge
of others (i.e., phonics principles). Also, preservice teachers seem to hold the common misconception that dyslexia is a visual
perception deficit rather than a problem with phonological processing. Implications for future research as well as teacher
preparation are discussed. 相似文献
947.
Students in their first year of university face a number of transition issues that can make realising their academic potential difficult. In the sciences, first-year courses cover a large amount of material across broad subject areas, which can make them troublesome for students without background knowledge, and students need to adapt to typically large class sizes and develop active, independent learning skills. We expected a student's prior learning to be important to their academic performance in a large, first-year introductory biology subject and analysed the relationships between students' results in this course with their senior high school results in related subjects over three years from 2007 to 2009. We predicted that students with prior learning in biology would have higher results than those without it, but that chemistry might also be important, given the biochemical nature of much of the course content. Students who completed biology at the senior high school-level did perform better than those who had not, but only if they also completed chemistry. Prior learning in biology was of no benefit to students in first-year biology, except when combined with chemistry, suggesting that potential differences in biology curricula between high school and the first year at university may need to be addressed. 相似文献
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950.
Anita K.W. Chan 《Gender and education》2011,23(6):745-759
Over the past two decades, the feminisation of primary school teaching has been identified by the media and government officials in Western countries as an important contributing factor to boys' academic problems. This panic, which has been criticised by feminists as a backlash and a form of recuperative politics, has promoted the development of research into gender and education, particularly studies related to the gendered culture of primary schools and on the masculinities of male teachers. However, male primary principals remain relatively under-researched in the literature, despite the importance of their structural position and increasing concern over the masculinisation of school leadership. This paper aims to contribute to the discussion by critically analysing the interpretive frameworks of 12 male primary school principals. The findings reveal not only the complex, contradictory and at times culturally specific gendered discourses that some male principals employ, but also their feminising and masculinising effects on the school workplace and leadership. 相似文献