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Amoebiasis is world wide in distribution and continues to be an important Public health problem. Intestinal amoebiasis may be present as dysentery, diarrhea or may stimulate other intra abdominal conditions. Clinical symptoms may not be seen in majority of patients, while amebic cysts are passed in the stool. This single-celled parasite is transmitted to humans via contaminated water and food. Amoebic dysentery can be accompanied by amebic infection of the liver and other organs. The present study was carried out to evaluate the changes in the circulating levels of neurohumors, their metabolizing enzymes and cortisol in these patients both before and after one month of chemotherapy. In the patients of amoebiasis the circulating acetylcholine (ACh), histamine, histaminase, cortisol, 5-Hydroxy tryptamine (serotonin) levels were significnatly enhanced with no change in the Dopamine-beta-hydroxylase (DBH) activity, while the activities of erythrocyte aceytylcholinesterase (AChE) and plasma Monoamine oxidase (MAO) were found decreased in comparison to normal healthy controls. After one month of treatment all the parameters reverted towards their control values, while the level of plasma histaminase remained still significantly high. The normal DBH activity reflects that there is no alteration in the circulating catecholamine levels. while the alteration in the levels of histamine, serotonin and cortisol may be due to the nonspecific response of the body to the stress of the disease and the parasitic infestation.  相似文献   
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This article describes the development of a questionnaire to discover primary school students’ perceptions of science, religion and the relationships between them on a range of topics that are known as Big Questions. The questionnaire was administered in 16 primary schools in England with over 750 students aged 10–11. The findings indicate that students in this age group have begun to consider how science and religion relate and that while there is a diversity of positions, a significant proportion perceived science and religion to conflict. Analysis of responses also indicated that primary school students’ epistemic insight was limited in relation to their understanding of the nature of science and, in particular, the idea that science has limitations. The basis and potential consequences of such views are considered and recommendations for teaching practice are presented, together with ideas for future research. It is anticipated that the study will inform teachers and curriculum planners developing approaches and guidance materials in science and religious education.  相似文献   
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Gross thigh volume is a key anthropometric variable to predict sport performance and health. Currently, it is either estimated by using the frustum method, which is prone to high inter-and intra-observer error, or using medical imaging, which is expensive and time consuming. Depth camera 3D-imaging systems offer a cheap alternative to measure thigh volume but no between-session reliability or comparison to medical imaging has been made. This experiment established between-session reliability and examined agreement with magnetic resonance imaging (MRI). Forty-eight male cyclists had their thigh volume measured by the depth camera system on two occasions to establish between-session reliability. A subset of 32 participants also had lower body MRIs, through which agreement between the depth camera system and MRI was established. The results showed low between-session variability (CV = 1.7%; Absolute Typical Error = 112 cm3) when measuring thigh volume using the depth camera system. The depth camera systematically measured gross thigh volume 32.6cm3 lower than MRI. These results suggest that depth camera 3D-imaging systems are reliable tools for measuring thigh volume and show good agreement with MRI scanners, providing a cheap and time-saving alternative to medical imaging analysis.  相似文献   
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In this study, a 3D passivated-electrode, insulator-based dielectrophoresis microchip (3D πDEP) is presented. This technology combines the benefits of electrode-based DEP, insulator-based DEP, and three dimensional insulating features with the goal of improving trapping efficiency of biological species at low applied signals and fostering wide frequency range operation of the microfluidic device. The 3D πDEP chips were fabricated by making 3D structures in silicon using reactive ion etching. The reusable electrodes are deposited on second glass substrate and then aligned to the microfluidic channel to capacitively couple the electric signal through a 100 μm glass slide. The 3D insulating structures generate high electric field gradients, which ultimately increases the DEP force. To demonstrate the capabilities of 3D πDEP, Staphylococcus aureus was trapped from water samples under varied electrical environments. Trapping efficiencies of 100% were obtained at flow rates as high as 350 μl/h and 70% at flow rates as high as 750 μl/h. Additionally, for live bacteria samples, 100% trapping was demonstrated over a wide frequency range from 50 to 400 kHz with an amplitude applied signal of 200 Vpp. 20% trapping of bacteria was observed at applied voltages as low as 50 Vpp. We demonstrate selective trapping of live and dead bacteria at frequencies ranging from 30 to 60 kHz at 400 Vpp with over 90% of the live bacteria trapped while most of the dead bacteria escape.  相似文献   
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Microfluidics is a relatively novel interdisciplinary research area with broad applications in chemistry, physics, material science, and biology. Despite the rapid growth of the field, students'' exposure to microfluidic technologies is still limited and often insufficient to appreciate the advantages over other commonly used technologies. To this end, we designed a five-day course, “Microfluidics for microbial ecology,” in which students with very different backgrounds learn the basics of microfluidic technologies and sample a range of applications in microbial ecology. The course was created for Master and Ph.D. students interested in applying microfluidics to their research and, therefore, followed an application-oriented approach. The presentation of critical aspects of fluid flow phenomena at the microscale and an outline of the advantages and constraints of the technology provide students with the background to design and perform microfluidics-based experiments. In order to improve the effectiveness of learning in a class with diverse interests and backgrounds, two active learning exercises were implemented. The first comprised the design of an individualized microfluidics experiment in parallel with the lectures: students were guided to apply each module to their personalized application and discuss it in groups. The second was a group experimental activity, in which students jointly set up, performed, analyzed, and presented a microfluidics-based experiment. Given the multidisciplinary teaching context, the course was able to foster common conceptual ground and promote discussion among students. This application-oriented approach built upon experimental activities and in-class discussion is well suited to promote learning in a technology-related subject such as microfluidics.  相似文献   
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The evolvable multiprocessor (EvoMP), as a novel multiprocessor system-on-chip (MPSoC) machine with evolvable task decomposition and scheduling, claims a major feature of low-cost and efficient fault tolerance. Non-centralized control and adaptive distribution of the program among the available processors are two major capabilities of this platform, which remarkably help to achieve an efficient fault tolerance scheme. This letter presents the operational as well as architectural details of this fault tolerance scheme. In this method, when a processor becomes faulty, it will be eliminated of contribution in program execution in remaining run-time. This method also utilizes dynamic rescheduling capability of the system to achieve the maximum possible efficiency after processor reduction. The results confirm the efficiency and remarkable advantages of the proposed approach over common redundancy based techniques in similar systems.  相似文献   
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