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排序方式: 共有426条查询结果,搜索用时 15 毫秒
31.
D Cook A Randolph P Kernerman C Cupido D King C Soukup C Brun-Buisson 《Canadian Metallurgical Quarterly》1997,25(8):1417-1424
OBJECTIVE: To evaluate the effect of guidewire exchange and new-site replacement strategies on the frequency of catheter colonization and infection, catheter-related bacteremia, and mechanical complications in critically ill patients. DATA SOURCES: We searched for published and unpublished research by means of MEDLINE and Science Citation Index, manual searching of Index Medicus, citation review of relevant primary and review articles, review of personal files, and contact with primary investigators. STUDY SELECTION: From a pool of 151 randomized, controlled trials on central venous catheter management, we identified 12 relevant randomized trials of catheter replacement over a guidewire or at a new site. DATA EXTRACTION: In duplicate and independently, we abstracted data on the population, intervention, outcome, and methodologic quality. DATA SYNTHESIS: As compared with new-site replacement, guidewire exchange is associated with a trend toward a higher rate of catheter colonization (relative risk 1.26, 95% confidence interval 0.87 to 1.84), regardless of whether patients had a suspected infection. Guidewire exchange is also associated with trends toward a higher rate of catheter exit-site infection (relative risk 1.52, 95% confidence interval 0.34 to 6.73) and catheter-related bacteremia (relative risk 1.72, 95% confidence interval 0.89 to 3.33). However, guidewire exchange is associated with fewer mechanical complications (relative risk 0.48, 95% confidence interval 0.12 to 1.91) relative to new-site replacement. Exchanging catheters over guidewires or at new sites every 3 days is not beneficial in reducing infections, compared with catheter replacement on an as-needed basis. CONCLUSIONS: Guidewire exchange of central venous catheters may be associated with a greater risk of catheter-related infection but fewer mechanical complications than new-site replacement. More studies on scheduled vs. as-needed replacement strategies using both techniques are warranted. If guidewire exchange is used, meticulous aseptic technique is necessary. 相似文献
32.
Pipes Randolph B.; McEwen Marylu K.; Ittenbach Richard F.; Sutherland Tracey 《Canadian Metallurgical Quarterly》1986,33(2):211
Conducted a national survey, using a questionnaire based on the organizational theory work of E. H. Schein (1978), to ascertain how 35 new faculty members in departments offering the doctoral degree in counseling or in counseling psychology viewed their transition from graduate students to faculty members. Results show that, of the 5 adjustment tasks described by Schein, deciphering the reward system was reported as the most difficult. Findings are outlined on how Ss (1) felt they were viewed by peers, (2) trusted chairpersons, and (3) identified what helped them most in their role. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
This paper describes the results of three case studies in which the subcontractor-fabricator relations had a significant negative effect on labor productivity of the subcontractor. Late vendor deliveries, fabrication or construction errors, and out-of-sequence deliveries plagued each of the three projects. On two projects, there were work stoppages because there were no materials. Unsequenced deliveries caused unnecessary crane movements and rework. On the third project, the output of the fabrication shop was not compatible with the output of the erection crew. The baseline productivity was calculated, and the loss of labor efficiency in each case was estimated to be 16.6, 28.4, and 56.8%. These percentages were compared with similar percentages calculated from other published articles that described inefficient site storage conditions and delivery methods. The labor inefficiencies caused by material management range from a low of 5.4% to a high of 56.8%. The schedule slippage on the three case study projects was estimated to be between 50 and 129%. 相似文献
34.
35.
Gary B. Randolph 《工程教育杂志》2000,89(2):119-122
The principles of “Writing Across the Curriculum” (WAC) has the potential to help educators more fully engage the learning styles of all students and achieve higher levels of learning according to the Bloom taxonomy. WAC exercises were built into an information systems class to create a fully collaborative learning approach. Students worked as a team on in‐class exercises, edited each other's work, and even collaborated on examinations. Students indicated that they learned more in this format. They also said that even examinations were learning experiences, incorporating brainstorming and discussion. 相似文献
36.
Ned Randolph 《电器评介》2007,(12)
美国Walt Disney公司旗下的ABC系列热门电视剧《疯狂主妇》(Desperate Housewives)、《实习医生格雷》(Grey's Anatomy)和《迷失》(Lost)的DVD光盘发行销售额使该公司2007年第四财季的净收入飙升了12%. 相似文献
37.
Burack Jacob A.; Enns James T.; Iarocci Grace; Randolph Beth 《Canadian Metallurgical Quarterly》2000,36(6):731
Visual search for compound patterns was examined in observers aged 6, 8, 10, and 22 years. The main question was whether age-related improvement in search rate (response time slope over number of items) was different for patterns defined by short- versus long-range spatial relations. Perceptual access to each type of relation was varied by using elements of same contrast (easy to access) or mixed contrast (hard to access). The results showed large improvements with age in search rate for long-range targets; search rate for short-range targets was fairly constant across age. This pattern held regardless of whether perceptual access to a target was easy or hard, supporting the hypothesis that different processes are involved in perceptual grouping at these two levels. The results also point to important links between ontogenic and microgenic change in perception (H. Werner, 1948, 1957). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Hugo E. Acosta-Martinez Susan M. Gourvenec Mark F. Randolph 《Soils and Foundations》2008,48(2):247-254
Shallowly embedded skirted foundations are an attractive alternative to piles for jacket structures and buoyant facilities as they can resist uplift but are cheaper to install than deep foundations. Bearing capacity of shallow skirted foundations in compression is moderately well understood while there is still considerable uncertainty over uplift capacity, particularly for loading sustained over a period of time. This paper reports results from beam centrifuge tests on a shallow skirted foundation in clay, subjected to uplift and compression. Rapid and sustained loading is considered and the effects of consolidation stress level and stress history on undrained capacity and sustained load response are reported. 相似文献
39.
The present trend in research on psychological stress is to examine the appraisal process for explanations of the wide individual differences typically found in responses to identical stressors. This approach comes at the expense of attempts to determine how aspects of the stimulus configuration tend to influence response independent of individual differences. The latter technique is unable to explain much of the variability in response, but it does avoid the circularity that regularly confronts the appraisal-based approach. In this article we describe the situational determinants of the primary appraisal of threat in a specific and systematic manner. Each potential determinant is broken down and the relevant empirical and theoretical literature is reviewed. Eight propositions about the workings of these factors are presented and discussed. Primary attention is given to the factors of event severity, imminence, and probability of occurrence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Increasing recycling will be a key strategy for moving toward sustainable materials usage. There are many barriers to increasing recycling, including quality issues in the scrap stream. Repeated recycling can compound this problem through the accumulation of tramp elements over time. This paper explores the importance of capturing recycler decision-making in accurately modeling accumulation and the value of technologies intended to mitigate it. A method was developed combining dynamic material flow analysis with allocation of those materials into production portfolios using blending models. Using this methodology, three scrap allocation methods were explored in the context of a case study of aluminum use: scrap pooling, pseudoclosed loop, and market-based. Results from this case analysis suggest that market-driven decisions and upgrading technologies can partially mitigate the negative impact of accumulation on scrap utilization, thereby increasing scrap use and reducing greenhouse gas emissions. A market-based allocation method for modeling material flows suggests a higher value for upgrading strategies compared to a pseudoclosed loop or pooling allocation method for the scenarios explored. 相似文献