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101.
Carlos Martínez-Figueroa Karen Corts-Sarabia Jos Antonio Tesser Poloni Enrique Alejandro Molina-Avilez Luis A. Palaoro Amalia Vences-Velzquez 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2022,32(2)
The internalization of apoptotic cells by non-phagocytic cells has been observed in different tissues and could be an important mechanism for the elimination of dying cells. Here, we describe a probable event of phagocytosis of apoptotic cells mediated by urothelial cells in urinary sediment. A 90-years-old male patient was admitted unconscious to the hospital, visible signs included: pale skin and dry mucous membranes, presumptively diagnosed as dehydration. Blood test revealed anaemia (haemoglobin 130 g/L) and hyperglycaemia (glucose 7.8 mmol/L), urinalysis showed a picture of urinary tract infection (leukocyturia and bacteriuria). The microscopic analysis of urinary sediment revealed the presence of urothelial cells and leukocytes internalized in urothelial cells. Anti-CD68 (membrane marker of macrophages) was tested by immunocytochemistry and a negative result was observed. Based on the findings phagocytosis of apoptotic cells mediated by urothelial cells was identified. This phenomenon can be observed in urinary sediment and should not be confused with a neoplastic process since it is a physiological event of cell elimination. 相似文献
102.
Roberto Carlos dos Santos Pacheco Vinícius Medina Kern Paulo Henrique S. Bermejo 《International Information and Library Review》2003,35(2-4):319
Cooperative organization has been proposed as a means to improve the usefulness of virtual libraries. Information interchange among library and other academic applications is often hindered by the lack of application interoperability. This hindrance may be overcome through the development of standards that allow for digital libraries to exchange and share information with other applications. The Graduate Program in Production Engineering (PPGEP) of the Federal University of Santa Catarina (UFSC) launched its Theses and Dissertations Bank (BTD) in 1995. BTD is possibly the first online academic digital library of theses. From a digital document repository, BTD evolved into a system that combines bibliometry and informetry features. BTD is used by students and faculty in their research activities, but also by decision makers from industry and academia. They use it, respectively, to search for specialists and to measure interest and knowledge interchange among PPGEP research areas. This article presents the history, features, and development prospects for the BTD project. The integration of BTD with other academic applications, especially those of the Brazilian national science and technology platform, is emphasized. 相似文献
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105.
Carlos Rodriguez‐Solano Salvador Sánchez‐Alonso Miguel‐Angel Sicilia 《British journal of educational technology : journal of the Council for Educational Technology》2015,46(6):1223-1235
Open textbook initiatives have appeared as an alternative to traditional publishing. These initiatives for the production of alternatively copyrighted educational resources provide a way of sharing materials through the Web. While the open model of peer‐produced materials enables the global reuse of textbooks, the combination of fragments to produce new textbooks tailored to particular needs is not easy. The heterogeneity of topics and target audiences, as well as the cultural and institutional differences of educational systems across the globe, raises the need for new compositional features, fostering—at the same time—the reuse of the newly produced combinations. This paper reviews the current models of reuse and sharing, and presents a quantitative analysis of the Connexions repository which provides evidence about the culture of reuse in open textbook initiatives. 相似文献
106.
José Carlos Núñez Natalia Suárez Rebeca Cerezo Julio González-Pienda Pedro Rosário Rosa Mourão 《教育心理学》2015,35(6):726-746
Homework (HW) is one of the most common school-related activities among parents, students and teachers. However, the need to assign HW to students has been extensively debated. The present investigation examines the relationship between specific HW variables (i.e. amount of HW completed, time spent on HW and perceived quality of HW time management) and academic achievement, while controlling for students’ gender and grade level. Participants included 454 students (ranging from 10 to 16?years of age) from three schools in northern Spain. A multivariate analyses of variance and path analyses showed that the amount of HW completed decreased with increased schooling, as did students’ perceived quality of HW time management. Data from hierarchical regression analyses completed by path analyses provided evidence that time spent on HW conjointly with perceived quality of HW time management explains how academic achievement is mediated by the amount of HW completed. These findings deepen the understanding of the complex impact of time spent on HW and on academic achievement. 相似文献
107.
Carlos Alberto Torres 《European Journal of Education》2015,50(3):262-279
This article focuses on the role of global universities and globalisations in an age of global interdependence and cosmopolitanism. Competing agendas that result from actions and reactions to multiple globalisations are considered in relation to global citizenship education. These agendas are crucial in understanding dilemmas of the local and the global in relation to education. Key emerging agendas are highlighted, including those of the hyperglobalisers, skeptics and transformationists. Three themes are central for this conversation, namely a) how multiple globalisations are impacting global life and academics, b) how networks have become privileged sites for global education, and c) the implications of globalisation and networks for global citizenship and global universities. 相似文献
108.
Leticia I. RAMíREZ-CAVAZOS Charles JUNGHANNS Rakesh NAIR Diana L. CáRDENAS-CHáVEZ Carlos HERNáNDEZ-LUNA Spiros N. AGATHOS Roberto PARRA 《Journal of Zhejiang University. Science. B》2014,15(4):343-352
研究目的:优化获得血红密孔菌(P.sanguineus)的最佳培养基组成,提高耐热漆酶的产量。创新要点:获得了目前文献报道的最高水平的漆酶活力。研究方法:通过单因素试验研究了不同培养基(番茄汁、麦麸、麦芽提取物和葡萄糖细菌蛋白胨培养基)和不同组合诱导剂(大豆油、阿魏酸、没食子酸、二甲基苯胺、酸性蓝62和活性蓝19分别与硫酸铜组合诱导剂)对P.sanguineus产耐热漆酶的影响。在此基础上采用中心组合试验设计,进一步研究了番茄汁培养基结合硫酸铜和大豆油组合诱导剂对P.sanguineus产耐热漆酶的影响。利用SAS10.0和响应面分析方法对试验结果进行了统计分析和建立回归模型。重要结论:通过中心组合设计优化得出P.sanguineus产耐热漆酶的最优培养基条件:以36.8%番茄汁为培养基,以3 mmol/L硫酸铜和1%大豆油作为组合诱导剂。该条件下在10 L搅拌槽生物反应器中漆酶活力达到了143 000 IU/L(2,2'-联氮双(3-乙基苯并噻唑啉-6-磺酸)为底物,pH值为3.0)。 相似文献
109.
We develop natural language processing techniques to identify the creation and impact of new technologies in the population of U.S. patents. We validate the new techniques and their improvement over traditional metrics based on patent classification and citations in two case-control studies. First, we collect patents linked to awards such as the Nobel prize and the National Inventor Hall of Fame. These patents likely cover radically new technologies with a major impact on technological progress and patenting. Second, we identify patents granted by the United States Patent and Trademark Office but simultaneously rejected by both the European and Japanese patent office. Such patents arguably lack novelty or cover small incremental advances over prior art and should have little impact on technological progress. We provide open access to code, data, and new measures for all utility patents granted by the USPTO up to May 2018 (see https://zenodo.org/record/3515985, DOI: 10.5281/zenodo.3515985). 相似文献
110.