全文获取类型
收费全文 | 354篇 |
免费 | 8篇 |
专业分类
教育 | 174篇 |
科学研究 | 164篇 |
各国文化 | 5篇 |
体育 | 5篇 |
信息传播 | 14篇 |
出版年
2023年 | 2篇 |
2022年 | 9篇 |
2021年 | 15篇 |
2020年 | 7篇 |
2019年 | 10篇 |
2018年 | 19篇 |
2017年 | 15篇 |
2016年 | 15篇 |
2015年 | 19篇 |
2014年 | 15篇 |
2013年 | 51篇 |
2012年 | 19篇 |
2011年 | 15篇 |
2010年 | 11篇 |
2009年 | 18篇 |
2008年 | 15篇 |
2007年 | 13篇 |
2006年 | 17篇 |
2005年 | 7篇 |
2004年 | 8篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 7篇 |
1999年 | 5篇 |
1998年 | 2篇 |
1997年 | 6篇 |
1995年 | 3篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有362条查询结果,搜索用时 15 毫秒
31.
This article reports on the third phase of a larger study that explored the perceptions of teachers about distributed leadership practices for inclusive education (IE) in primary schools involved in IE reform in Bangladesh. The Distributed Leadership Practice for Inclusive Education scale was developed specifically for this study to collect data. Participants for the present study were head teachers and teachers from 308 public primary schools. The results of this study indicate that teachers perceived that distributed leadership practices for IE were present in primary schools in Bangladesh. The findings indicate that teachers' perceptions about distributed leadership practices for IE have a significant positive correlation with their satisfaction about the implementation of IE policy. 相似文献
32.
The purpose of this paper was to investigate Malaysian primary pre-service teachers’ perceptions of students’ disruptive behaviour and their self-reported strategies to prevent and to manage such behaviours. Results indicate that Malaysian pre-service teachers understand disruptive behaviours to be those that disrupt the learning and teaching process. They identified the cause of student disruptive behaviour as factors residing within the individual student. Pre-service teachers here reported preventative strategies in terms of changing teaching strategies and threats to use punishment. When addressing students’ disruptive behaviour, pre-service teachers reported that they would use one-to-one counselling with students and remove tokens or hold back rewards. A discussion regarding the implications for teacher education institutions and future research concludes this paper. 相似文献
33.
Yogesh M. Patel Sanidhya Jain Abhishek Kumar Singh Kedar Khare Sarita Ahlawat Supreet Singh Bahga 《Biomicrofluidics》2020,14(6)
We present design, characterization, and testing of an inexpensive, sheath-flow based microfluidic device for three-dimensional (3D) hydrodynamic focusing of cells in imaging flow cytometry. In contrast to other 3D sheathing devices, our device hydrodynamically focuses the cells in a single-file near the bottom wall of the microchannel that allows imaging cells with high magnification and low working distance objectives, without the need for small device dimensions. The relatively large dimensions of the microchannels enable easy fabrication using less-precise fabrication techniques, and the simplicity of the device design avoids the need for tedious alignment of various layers. We have characterized the performance of the device with 3D numerical simulations and validated these simulations with experiments of hydrodynamic focusing of a fluorescently dyed sample fluid. The simulations show that the width and the height of the 3D focused sample stream can be controlled independently by varying the heights of main and side channels of the device, and the flow rates of sample and sheath fluids. Based on simulations, we also provide useful guidelines for choosing the device dimensions and flow rates for focusing cells of a particular size. Thereafter, we demonstrate the applicability of our device for imaging a large number of RBCs using brightfield microscopy. We also discuss the choice of the region of interest and camera frame rate so as to image each cell individually in our device. The design of our microfluidic device makes it equally applicable for imaging cells of different sizes using various other imaging techniques such as phase-contrast and fluorescence microscopy. 相似文献
34.
The effect of peer feedback for blogging on college students' reflective learning processes 总被引:1,自引:0,他引:1
Reflection is an important prerequisite to making meaning of new information, and to advance from surface to deep learning. Strategies such as journal writing and peer feedback have been found to promote reflection as well as deep thinking and learning. This study used an empirical design to investigate the interaction effects of peer feedback and blogging on college students' reflective thinking skills and their learning approaches. Forty-four first- and second-year undergraduate students participated in the study. Students kept blogs each week throughout a whole semester. Two journals were sampled at the beginning and end of the semester for each student. A repeated measure one-way ANOVA suggested that students' reflective thinking level increased significantly over time; however, peer feedback was found to negatively affect students' reflective thinking skills. The result of the study suggests more carefully designed uses in the future. 相似文献
35.
Everybody is familiar with the ubiquitous term ‘species’. But what is a species? Undeniably, this is one of the most complex dilemmas in the history of biology. There is no other concept in biology as elementary yet controversial as the concept of species. In practice, a species is regarded as the fundamental unit of comparison in all biological disciplines like systematics, evolution, ecology, ethology, physiology, and genetics. However, little agreement exists in the scientific community regarding the nature of species, whether it is a real entity or a cultural artifact, its biological significance or how to delineate a species. This article is a review of the seemingly endless debate on the species concept and its implications. 相似文献
36.
Chitra Upadhyaya Sandhya Mishra P. P. Singh Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2005,20(1):30-34
Serum antioxidant status and peroxidative stress was estimated in 30 pregnant women, their newborn infants and 25 non-pregnant
women. Serum Ascorbic acid, α-tocopherol, retinol & β-carotene levels were found to be significantly reduced and peroxidative
stress was significantly higher in mothers as compared to matched non-pregnant women. Newborn had significantly higher levels
of ascorbic acid as compared to their mother but had significantly lower levels of lipid soluble vitamins. The peroxidative
stress in newborn was found to be significantly less as compared to their mothers. A positive correlation of ascorbic acid
and α-tocopherol levels between mother and newborn reflects that their status in mother does influence the newborn status. 相似文献
37.
38.
Ritu Sharma Mridula Mahajan Ravi Kant 《Indian journal of clinical biochemistry : IJCB》2004,19(1):10-13
Serum total lipids (cholesterol and triglyceride), lipoproteins (VLDL, LDL and HDL) and Apolipoprotein-B levels of normal
healthy individuals (n=25) and coronary artery disease patients (n=25) were estimated. The objective of the present study
was to ascertain the role of apo-B in causation and inheritance of coronary artery disease. It was observed that on an average
serum total cholesterol and triglyceride more than 200 mg/dl bring the individuals to a risk of coronary artery disease (CAD)
irrespective of the age. CAD patients achieved this value at an early age (35–45 years). Similarly VLDL and LDL levels were
found to be significantly raised in CAD patients when compared to that of age matched normal individuals, with patients achieving
risk values at an early age. HDL levels were found to be significantly lower in CAD patients as compared to normal individuals.
Serum apo-B levels were significantly raised in CAD patients as compared to age matched normal individuals. Patients with
positive family history of CAD had raised serum apo-B levels than those having negative family history. A positive coefficient
of correlation was observed between serum apo-B and LDL levels suggesting that more the number of Apo-B particles, more will
be the synthesis of atherogenic particle (LDL). Patients with negative family history had serum apo-B levels closer to those
of normal individuals and in these individuals HDL levels were found to be significantly lowered, suggesting that loss of
scavenger role of HDL could be the risk factor responsible for the causation of CAD in these patients, with negative family
history of coronary artery disease. 相似文献
39.
40.
Gora Dadheech Sandhya Mishra Shiv Gautam Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2006,21(2):34-38
A disturbance in the antioxidant defense system including α-tocopherol, ascorbic acid and reduced glutahtione metabolism due
to free radical induced oxidative injury has been implicated in various neuro-psychiatric disorders. The roles of these antioxidants,
changes in their blood levels and correlation with oxidative stress were studied in a common psychiatric illness Schizophrenia.
Fifty-eight subjects of either sex ranging in age from 18–60 years divided into two age groups (≤40 and >40 years) diagnosed
for schizophrenia, and forty age and sex-matched normal subjects as controls were included in the study. Blood samples were
analyzed for malondialdehyde (MDA), α-tocopherol, total ascorbic acid (TAA), dehydro ascorbic acid (DHAA), reduced ascorbic
acid (RAA), leucocyte ascorbic acid (LAA) and reduced glutathione (GSH). A decrease in the levels of α-tocopherol, total ascorbic
acid and reduced glutathione was found in schizophrenics compared to normal controls. Further a significant rise in oxidative
stress and decreased antioxidant status was observed in the chronic stage of schizophrenia as compared to those in acute condition.
A significant rise in dehydroascorbic acid with concomitant fall in reduced ascorbic acid suggests scavenging action of ascorbic
acid and its utilization with increased oxidative stress as indicated by high blood malondialdehyde levels. Leucocyte ascorbic
acid, a better index of ascorbic acid status was also found to be reduced in schizophrenics, suggesting depletion of body
stores of ascorbic acid and the condition worsened with advancing age. 相似文献