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571.
Rada RF 《Health information and libraries journal》2007,24(3):210-215
OBJECTIVES: To explore how often newspapers cover the retraction of a medical journal article and whether newspaper coverage corresponds with the appearance of a press release about the retraction. METHODS: Fifty citations were identified in PubMed that had been indexed with the Medical Subject Heading 'Retracted Publication'. Next, the archives of LexisNexis's 'Major Newspapers' and EurekAlert's press releases were searched to find references to those retracted publications. RESULTS: Newspaper articles addressed exactly three of the 50 retracted publications, and press releases, exactly four of the 50 retracted publications. All three retracted publications that received newspaper coverage also had a press release. In other words, newspapers only covered a retraction that had been introduced by a press release. CONCLUSION: One would expect that newspaper coverage would increase after a press release, but the suggested relationships among a medical journal article retraction, a press release and newspaper coverage should be further investigated. If the linkage suggested by the data of this study holds, and if newspaper coverage stimulates library patron interest, then a medical library might prepare itself for information requests following a press release. 相似文献
572.
Immunological sensitivity and specificity properties of isolated Plasmodium falciparum (GPL) antigen from culture supernatant
have been measured and compared with malarial antigens and non malarial filtered paper blood sera for potency and efficacy.
Latex bead coded GPL, Pf and RESA antigens immunoreaction properties of human filter paper blood samples (FPB) were studied
by laser light scattering immunoassay (LIA) and Enzyme linked immunoabsorbent assay (ELISA) techniques. Results of GP. antigen
sensitivity study by LIA method showed a very high malaria antibody binding response (MABR) i.e. 6% compared with 78% with
RESA and 88% Pf antigens. Malaria detection by ELISA method also found similar results. Specificity study of GPL antigen for
different non malarial filter paper blood sera (NMFS) showed no immunoreaction however Pf and RESA antigen showed few positive
immunological responses. These results suggest that sensitivity and specificity properties of isolated GPL antigen is better
than other antigens. 相似文献
573.
Nihal G. Maremanda Kislay Roy Rupinder K. Kanwar Vidyarani Shyamsundar Vijayalakshmi Ramshankar Arvind Krishnamurthy Subramanian Krishnakumar Jagat R. Kanwar 《Biomicrofluidics》2015,9(5)
The role of circulating tumor cells (CTCs) in disease diagnosis, prognosis, monitoring of the therapeutic efficacy, and clinical decision making is immense and has attracted tremendous focus in the last decade. We designed and fabricated simple, flat channel microfluidic devices polydimethylsiloxane (PDMS based) functionalized with locked nucleic acid (LNA) modified aptamers (targeting epithelial cell adhesion molecule (EpCAM) and nucleolin expression) for quick and efficient capture of CTCs and cancer cells. With optimized flow rates (10 μl/min), it was revealed that the aptamer modified devices offered reusability for up to six times while retaining optimal capture efficiency (>90%) and specificity. High capture sensitivity (92%) and specificity (100%) was observed in whole blood samples spiked with Caco-2 cells (10–100 cells/ml). Analysis of blood samples obtained from 25 head and neck cancer patients on the EpCAM LNA aptamer functionalized chip revealed that an average count of 5 ± 3 CTCs/ml of blood were captured from 22/25 samples (88%). EpCAM intracellular domain (EpICD) immunohistochemistry on 9 oral squamous cell carcinomas showed the EpICD positivity in the tumor cells, confirming the EpCAM expression in CTCs from head and neck cancers. These microfluidic devices also maintained viability for in vitro culture and characterization. Use of LNA modified aptamers provided added benefits in terms of cost effectiveness due to increased reusability and sustainability of the devices. Our results present a robust, quick, and efficient CTC capture platform with the use of simple PDMS based devices that are easy to fabricate at low cost and have an immense potential in cancer diagnosis, prognosis, and therapeutic planning. 相似文献
574.
ABSTRACTAustralia has participated in the world-wide growth of women’s football particularly since the 1970s, but long before that the game was played recreationally and competitively by women in Australia. Women have struggled to overcome active opposition to their taking part in the sport and neglect of their achievements which are considerable. This article provides an outline of the history of the game both nationally and in its international context. It also tries to capture the experience of some of the pioneers of the women’s game and its modern practitioners, revealing some of the ways in which overt and covert discrimination still hinders recognition of their achievements. 相似文献
575.
Roy?B.?ClarianaEmail author Michael?B.?Wolfe Kyung?Kim 《Educational technology research and development : ETR & D》2014,62(5):601-616
This investigation applies two approaches for representing and comparing text structures as undirected network graphs to describe the influence of narrative and expository lesson texts on readers’ knowledge structure elicited as free recall. Narrative and expository lesson texts and undergraduate participants’ free recall essays (n = 90) from a study by Wolfe and Mienko (Br J Educ Psychol 77, 541–564, 2007) were reanalyzed for lexical proximity as sequential occurrence of selected important terms in the text and as actual minimum distances between these terms. The proximity data were then rendered as Pathfinder networks for analysis. Compared to human-rater benchmark measures, the convergent validity of the sequential approach (range of r = .53 to .83, median r = .70) was a little better than that of the minimum distance approach (.51 to .80, median r = .67). Further, we anticipated that the lesson text structure would be reflected in the text structure of the free recall essays, but this was not observed. On average, the essays in all three lesson conditions tended to converge on a sequential expository structure. Further, compared to the expository lesson texts, the narrative lesson text had a distinctly different influence on posttest recall essay text structures. Overall then, the sequential occurrence approach appears to provide a reasonably good, automatically derived method for representing and comparing lesson texts and participants’ essays as network graphs. If further confirmed and fully automated, there is a wide range of application of such measurement approaches for learning and research. 相似文献
576.
Frédéric Guay Catherine F. Ratelle Amélie Roy David Litalien 《Learning and individual differences》2010,20(6):644-653
Three conceptual models were tested to examine the relationships among academic self-concept, autonomous academic motivation, and academic achievement. This allowed us to determine whether 1) autonomous academic motivation mediates the relation between academic self-concept and achievement, 2) academic self-concept mediates the relation between autonomous academic motivation and achievement, or 3) both motivational constructs have an additive effect on academic achievement. A total of 925 high school students (404 boys and 521 girls) were asked to complete a questionnaire on two occasions separated by a year interval. Results from SEM analyses provided good support for the hypothesized model positing that autonomous academic motivation mediates the academic self-concept–academic achievement relation. Results are discussed in light of self-determination theory and self-concept theory. 相似文献
577.
578.
579.
Roy Hawkey 《Curator: The Museum Journal》2003,46(1):42-59
This paper describes a range of theatrical events developed by the Education Unit of the Natural History Museum, London. Theater is used to target non‐traditional audiences, thereby helping meet the museum's educational mandate in innovative ways. The museum's galleries have recently hosted a variety of characters, traditional and contemporary, historical and fictional, in a number of dramatic formats: ensemble pieces, role‐playing, puppetry, dance, mime, and acrobatics. The examples described here provide the occasion for exploring related issues, such as the museum's overall objectives for the program, the responses of visitors, and the spatial and temporal limitations to the design process. 相似文献
580.
Despite its existence for over six decades, the practice of human performance technology (HPT) has not been widely accepted within organizations. Varying levels of confusion surround the understanding of HPT, which has been influenced by myriad fields and disciplines. Although HPT is focused on improving performance at the organizational, team, and individual levels, it does not own the practice of performance improvement. The goal of optimal performance across various functions and levels within an organization is not confined to HPT but extends to process improvement, human resource development, organizational development, knowledge management, and several other areas. Therein lies the problem: A lack of consideration about the boundaries that delineates the field has ramifications for both the research on and the practice of HPT. This study examines the domains and disciplines that HPT proponents consider central to the field. 相似文献