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991.
S.M.RAHIM A.G.MAZLAN K.D.SIMON J.P.DELAUNOY P.LAURENT 《Journal of Zhejiang University. Science. B》2014,(2)
研究目的:假腮的功能早已引起科学家兴趣,但还有待阐明。本文通过研究硬骨鱼类品种虹鳟鱼(Oncorhynchus mykiss)的假腮碳酸酐酶的免疫定位,来探讨假腮碳酸酐酶的生理功能。研究方法:免疫组织化学染色技术。重要结论:免疫组化结果显示碳酸酐酶分布在假腮细胞中,更精确地说是在其细胞顶端分布。细胞基底端、管状系统、毛细血管和柱细胞均无免疫染色。免疫细胞化学定位进一步验证了这些结果,并显示一部分是细胞质碳酸酐酶,其余的与细胞膜结构连接。此外,腔隙层未显示出免疫过氧化物酶的活性。本研究揭示了假腮碳酸酐酶的功能与细胞外介质有关,碳酸酐酶能干预传入神经纤维刺激机制。 相似文献
992.
Benjamin D. Plummer Brian M. Galla Amy S. Finn Sarah D. Patrick David Meketon Julia Leonard Calvin Goetz Elizabeth Fernandez‐Vina Sara Bartolino Rachel E. White Angela L. Duckworth 《Mind, Brain, and Education》2014,8(1):15-20
Schools are an important context for both basic and applied scientific research. Unlike the laboratory, however, the physical and social conditions of schools are not under the exclusive control of scientists. In this article, we liken collecting data in schools to putting on a theatrical production. We begin by describing the large cast of characters whose collaborative efforts make school‐based research possible. Next, we address the critics, including the university Institutional Review Board (IRB) and school administrators, whose feedback often improves the final study design. We then turn our attention to set building, stage directions, and rehearsals—key steps in the iterative process of refining study procedures. We end with a discussion of the day of data collection itself and activities that take place after the curtain drops. Throughout, we make recommendations based on our recent experience collecting data at several high schools. 相似文献
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994.
M. P. Biktimirov S. A. Polikarpov A. Yu. Scherbakov P. V. Efremov D. L. Solodkin 《Scientific and Technical Information Processing》2014,41(3):178-182
The main aspects related to the development of a system for the aggregation and use of scientific results (hereinafter, the System) are discussed. A unified comprehensive approach to the development of the System and the qualitative improvement of the information about the performance of the Russian research sector provided to the target audience is being suggested for use by academic institutions, government regulators, and the business community. The improvement is meant to be achieved through the development of technology that provides access to the relevant electronic resources. The presented conclusions lay the basis for a range of research and development works in the field related to the collection of scientific results. 相似文献
995.
996.
Helen S. Du Samuel K.W. Chu Gary E. Gorman Felix L.C. Siu 《Library & information science research》2014
Three groups of social bookmarking users, namely experienced users, users with moderate level of experience, and novice users, were investigated, in terms of their reported tagging behaviors, perceived usefulness of social bookmarking in information discovery and management, and perceived usefulness of the bookmarking features provided. Based on the empirical analysis of the Connotea users, who are primarily in academia, the study shows that experienced academic users generally prefer to use social bookmarking while moderately experienced and novice users still prefer to use the traditional bookmarking methods, such as creating and using bookmarks on a dedicated computer. Experienced academic users were also found to create more tags per bookmark comparing to the other two groups. Most novice academic users, however, only created one tag per bookmark, which just met Connotea's minimum requirement. Surprisingly different from the collaborative design nature of the social bookmarking systems, the study finds that our participants, particularly experienced academic users, prefer to create and use their own bookmarks rather than sharing bookmarks created by others. In fact, experienced users have significantly higher frequency (once every two weeks) of creating bookmarks than the other two groups (once a month or less). In addition, website design features and functions, such as automatic collection of bibliographic information, are regarded by all participants as helpful for information discovery. The in-depth examination and discussion of the opinions of Connotea users may be useful for further improvement of the design features and usage applications, particularly for academic social bookmarking websites. The results may also have potential implications to the future development of social bookmarking services in general. 相似文献
997.
This article describes a half-day preconference that focused on the library as publisher. It examined how the movement from print to online publication has impacted the roles of libraries and their ability to take on new roles as publishers. The session explored the benefits of libraries becoming publishers, and discussed Open Access, what it is and is not and its importance to libraries and scholarly communication. A detailed case study of the publishing operations of the University Library System at the University of Pittsburgh was presented as an example of a successful library publishing program. The session provided an opportunity for participants to discover ways that libraries can be involved in publishing. 相似文献
998.
A method is described for determining multiple loop feedback topologies which yield minimum sensitivities for symmetrical, all-pole bandpass filters. The procedure begins with a follow-the-leader feedback (FLF) topology and additional feedback loops are constructed until minimum sensitivity is achieved. Filters comprised of identical second-order sections and non-identical sections, respectively, are considered. 相似文献
999.
1000.