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11.
As early as 2001, the need for the ‘functional motif theory’ was pointed out, to assist the rational design of functional materials. The properties of materials are determined by their functional motifs and how they are arranged in the materials. Uncovering functional motifs and their arrangements is crucial in understanding the properties of materials and rationally designing new materials of desired properties. The functional motifs of materials are the critical microstructural units (e.g. constituent components and building blocks) that play a decisive role in generating certain material functions, and can not be replaced with other structural units without the loss, or significant suppression, of relevant functions. The role of functional motifs and their arrangement in materials, with representative examples, is presented. The microscopic structures of these examples can be classified into six types on a length scale smaller than ∼10 nm with maximum subatomic resolution, i.e. crystal, magnetic, aperiodic, defect, local and electronic structures. Functional motif analysis can be employed in the function-oriented design of materials, as elucidated by taking infrared non-linear optical materials as an example. Machine learning is more efficient in predicting material properties and screening materials with high efficiency than high-throughput experimentation and high-throughput calculations. In order to extract functional motifs and find their quantitative relationships, the development of sufficiently reliable databases for material structures and properties is imperative.  相似文献   
12.
2008年北京奥运会的市场开发工作是一个动态、开放的系统.环境的不确定性,让北京奥运会的市场开发在各种不断变化的环境中既获得无限商机,又面临巨大挑战.通过互联网、查阅相关文献、请教有关方面的专家等方法获取资料,分析2008年奥运会市场开发的宏观环境(包括政治、文化、经济、技术、环境五方面),和微观环境(包括政府、企业、传媒、法律平台、相关组织五方面).分别从宏观和微观两个层面上分析其对北京奥运会市场开发产生的影响,并对北京奥运会市场开发环境提出要求.  相似文献   
13.
Sera samples of 7 microscopic haematuria cases collected before and after treatment with Diethylcarbamazine citrate, (DEC), 9 microfilaraemic cases and 19 endemic normal individuals were analysed for filarial antigen and IgG antibody levels. Filarial antigen was detected in 5 of the 7 microscopic haematuria cases, of which 3 turned negative for antigen after treatment with DEC. While none of the 7 haematuria cases were positive for filarial IgG antibodies, before the DEC treatment, all of them turned positive after DEC treatment. The sensitivity and specificity values(to detect mf +ve cases) were 89% and 90% respectively for the detection of filarial antigen and 78% and 95% respectively for the detection of filarial IgG antibodies.  相似文献   
14.
Changes in medical school curricula often require educators to develop teaching strategies that decrease contact hours while maintaining effective pedagogical methods. When faced with this challenge, faculty at the University of Cincinnati College of Medicine converted the majority of in‐person histology laboratory sessions to self‐study modules that utilize multiple audiovisual modalities and a virtual microscope platform. Outcomes related to this shift were investigated through performance on in‐house examinations, results of the United States Medical Licensing Examination® (USMLE®) Step 1 Examination, and student feedback. Medical School College Admissions Test® (MCAT®) scores were used as a covariate when comparing in‐house examinations. Results revealed no significant change in performance on in‐house examinations when the content being assessed was controlled (F(2, 506) = 0.676, P = 0.51). A significant improvement in overall practical examination grade averages was associated with the self‐study modules (F(6, 1164) = 10.213, P < 0.01), but gradual changes in examination content may explain this finding. The histology and cell biology portion of USMLE Step 1 Examination remained consistent throughout the time period that was investigated. Student feedback regarding the self‐study modules was positive and suggested that features such as instructor narrated videos were an important component of the self‐study modules because they helped recreate the experience of in‐person laboratory sessions. Positive outcomes from the student perspective and no drop in examination performance suggests that utilizing self‐study modules for histology laboratory content may be an option for educators faced with the challenge of reducing contact hours without eliminating content. Anat Sci Educ 10: 276–285. © 2016 American Association of Anatomists.  相似文献   
15.
Virtual microscopy (VM) has been utilized to improve students' learning experience in microscope laboratory sessions, but minimal attention has been given to determining how to use VM more effectively. The study examined the influence of VM on academic performance and teacher and student perceptions and compared laboratory test scores before and after VM incorporation. A total of 662 third-year students studying histology and 651 fourth-year students studying pathology were divided into two groups. The light microscopy (LM) group used a light microscope in 2014 and 2015, while the LM + VM group used the VM platform and a light microscope in 2016 and 2017. Four factors positively predict laboratory scores (R square, 0.323; P < 0.001): (i) the pathology course and test-enhanced learning, (ii) the VM platform and experience, (iii) medical students and lecture scores, and (iv) female students. The LM + VM group exhibited less score variability on laboratory examinations relative to their mean than the LM group. The LM + VM group was also associated with fewer failing grades (F grade; odds ratio, 0.336; P < 0.001) and higher scores (A grade; odds ratio, 2.084; P < 0.001) after controlling for sex, school, course, and lecture grades. The positive effect of the VM platform on laboratory test grades was associated with prior experience using the VM platform and was synergistic with more interim tests. Both teachers and students agreed that the VM platform enhanced laboratory learning. The incorporation of the VM platform in the context of test-enhanced learning may help more students to master microscopic laboratory content.  相似文献   
16.
Monitoring of student learning through systematic formative assessment is important for adjusting pedagogical strategies. However, traditional formative assessments, such as quizzes and written assignments, may not be sufficiently timely for making adjustments to a learning process. Technology supported formative assessment tools assess student knowledge, allow for immediate feedback, facilitate classroom dialogues, and have the potential to modify student learning strategies. As an attempt to integrate technology supported formative assessment in the laboratory section of an upper‐level histology course, the interactive application Learning CatalyticsTM, a cloud‐based assessment system, was used. This study conducted during the 2015 Histology courses at Cornell University concluded that this application is helpful for identifying student misconceptions “on‐the‐go,” engaging otherwise marginalized students, and forming a new communication venue between students and instructors. There was no overall difference between grades from topics that used the application and grades from those that did not, and students reported that it only slightly helped improve their understanding of the topic (3.8 ± 0.99 on a five‐point Likert scale). However, they highly recommended using it (4.2 ± 0.71). The major limitation was regarding the image display and graphical resolution of this application. Even though students embrace the use of technology, 39% reported benefits of having the traditional light microscope available. This cohort of students led instructors to conclude that the newest tools are not always better, but rather can complement traditional instruction methods. Anat Sci Educ 10: 328–338. © 2016 American Association of Anatomists.  相似文献   
17.
不同处理条件对洋葱鳞茎表皮细胞骨架形态影响的研究   总被引:1,自引:0,他引:1  
细胞骨架是活细胞的重要结构,研究细胞骨架的形态对于进一步研究其功能具有重要意义。本研究以洋葱为材料,设置了4个不同的1%Triton X-100抽提非骨架蛋白时间(10min、15min、25min、40min)对洋葱细胞骨架显微观察的关键条件进行了优化,同时分析了细胞环境温度(-18℃、4℃、20℃、50℃),紫外线照射活细胞(0min、60min),0.1mol/L Ca^2+处理及0.1%秋水仙素处理对洋葱细胞骨架形态观察效果的影响。结果表明:1%Triton X-100抽提非骨架蛋白25min观察效果较好;-18℃、50℃,紫外线辐射60min,0.1mol/L Ca^2+和秋水仙素处理均会影响细胞骨架的观察。  相似文献   
18.
福柯对权力的分析做出了独特贡献,他不仅颠覆了传统的权力思想,而且建立了一种全新的微观权力理论。他在名著《规训与惩罚》一书中所阐述的微观权力是多形态的、非实体的、关系的、生产性及与知识密不可分等特点;层级监视、规范化裁决与检查的技术,以及空间、时间与动作的规定性策略,使得微观权力无所不在。福柯的微观权力分析对认知现代社会的权力实践具有积极的方法论意义。  相似文献   
19.
颗粒材料力学性质的离散元数值模拟   总被引:2,自引:0,他引:2  
基于颗粒离散元法对二维颗粒体进行了双轴压缩数值模拟.将离散系统中的变形与连续体中相应的变形联系起来,应用于颗粒离散元方法中平均应力的计算,比较了不同颗粒形状、颗粒间摩擦系数对颗粒体的微观-宏观力学性能的影响,并分别考虑了不同摩擦系数下,颗粒颗粒间接触力的法向分量和切向分量对剪切应力的贡献.本文的计算结果表明颗粒的形状和表面性质对颗粒体的力学性能有显著的影响.  相似文献   
20.
分析和讨论晶体宏观对称性与微观对称性的区别和联系,明确晶体的宏观对称性是微观对称性的宏观反映,而平移对称性的存在与否,是晶体的微观对称性与宏观对称性之间的分水岭。  相似文献   
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