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排序方式: 共有189条查询结果,搜索用时 15 毫秒
1.
JC Wyatt S Paterson-Brown R Johanson DG Altman MJ Bradburn NM Fisk 《Canadian Metallurgical Quarterly》1998,317(7165):1041-1046
OBJECTIVE: To evaluate the effectiveness of an educational visit to help obstetricians and midwives select and use evidence from a Cochrane database containing 600 systematic reviews. DESIGN: Randomised single blind controlled trial with obstetric units allocated to an educational visit or control group. SETTING: 25 of the 26 district general obstetric units in two former NHS regions. SUBJECTS: The senior obstetrician and midwife from each intervention unit participated in educational visits. Clinical practices of all staff were assessed in 4508 pregnancies. INTERVENTION: Single informal educational visit by a respected obstetrician including discussion of evidence based obstetrics, guidance on implementation, and donation of Cochrane database and other materials. MAIN OUTCOME MEASURES: Rates of perineal suturing with polyglycolic acid, ventouse delivery, prophylactic antibiotics in caesarean section, and steroids in preterm delivery, before and 9 months after visits, and concordance of guidelines with review evidence for same marker practices before and after visits. RESULTS: Rates varied greatly, but the overall baseline mean of 43% (986/2312) increased to 54% (1189/2196) 9 months later. Rates of ventouse delivery increased significantly in intervention units but not in control units; there was no difference between the two types of units in uptake of other practices. Pooling rates from all 25 units, use of antibiotics in caesarean section and use of polyglycolic acid sutures increased significantly over the period, but use of steroids in preterm delivery was unchanged. Labour ward guidelines seldom agreed with evidence at baseline; this hardly improved after visits. Educational visits cost pound860 each (at 1995 prices). CONCLUSIONS: There was considerable uptake of evidence into practice in both control and intervention units between 1994 and 1995. Our educational visits added little to this, despite the informal setting, targeting of senior staff from two disciplines, and donation of educational materials. Further work is needed to define cost effective methods to enhance the uptake of evidence from systematic reviews and to clarify leadership and roles of senior obstetric staff in implementing the evidence. 相似文献
2.
Researchers carrying out non-therapeutic research that involves the administration of drugs of abuse to human volunteers can be faced with many ethical and practical questions. The history of this type of research is relatively brief, with little in the way of published information relevant to carrying out behavioral pharmacological research with human participants. The aim of this article is to raise issues that occur in most studies of this type and to provide solutions that we have found acceptable and which have been approved by a variety of institutions and regulatory agencies. Clearly, there are other approaches that would work equally as well, and we are not attempting to provide 'the' answer to many of the issues raised. We believe that raising these issues and providing our perspectives is important for stimulating others to discuss them and for all of us to strive, where possible, to reach a consensus concerning ethical practices and to become aware of gaps and pitfalls. The topics discussed range from the nuts and bolts of acquiring and keeping track of drugs, to selecting research participants and designing ethical studies that protect our volunteers while still collecting scientifically useful data. 相似文献
3.
The Swedish Fire Research Board and the U.S. Federal Emergency Management Agency are sponsoring a project to further the understanding of the basic mechanisms involved, as well as to support the development of standards for and to seek ways of improving the performance of portable fire suppression systems used by fire departments.This paper describes a physically based computer model developed to simulate one aspect of the problem: the manual suppression of postflashover fires. This includes: (1) an overview of the physical basis behind the model; (2) a comparison of model predictions with available experimental data, and (3) an analysis of fire suppression effectiveness using the model.The analysis concludes that, when direct access and extinguishment of the burning fuel is not possible, improved fire control occurs with water sprays having a Rosin-Rammler distribution of droplet sizes with volume-median-drop diameters in the 0.15 to 0.35 mm range. This agrees with available experimental data. It is also shown that fire fighting venting and standoff distance requirements may lead to more severe fires requiring more water for control; although venting and water spray induced air/gas flow also serve to channel hot steam and gases away from the fire fighter adding to his safety. The analysis also shows that allowing higher gas and surface temperatures at fire control through improved fire fighter protective clothing and equipment design reduces water flow rate requirements. Additional experimental work is recommended before all these conclusions are considered definitive.
Reference: L. M. Pietrzak and G. A. Johanson, Directions for Improving Manual Fire Suppression Using a Physically Based Computer Simulation,Fire Technology, Vol. 22, No. 3, August, 1986, p. 184. 相似文献
4.
Detecting the incidence and impact of illegal insider trading is a difficult process since access to the actual trading records of insiders that overlap precisely with fraudulent events is difficult. This paper provides a case study of a specific IT stock in Canada that was successfully prosecuted in the Canadian court system for market manipulation and illegal insider trading violations. The study provides a quantification of the impact of insider trading activities by the President directly through his own account or through accounts under his control, and illustrates the impact of some off-exchange transactions by the impugned parties. Overall, the costs of the insider trading violations are quite high, given the significant wealth effects produced by the events surrounding this case. 相似文献
5.
Interactive Workspaces 总被引:1,自引:0,他引:1
We are rapidly entering a world in which people equip themselves with a small constellation of mobile devices and pass through environments rich in embedded technology. However, we are still a long way from harnessing the power of this technology in a way that seamlessly and invisibly assists users in their day-to-day activities. Bringing pervasive computing to maturity requires innovations in systems integration and human-computer interaction (HCI). To investigate these challenges, Stanford University's Interactive Workspaces project (http://iwork.stanford.edu/) is exploring team-based collaboration in technology-augmented environments. These workspaces are designed to allow groups of five to ten people to work together using computing and interaction devices on many scales. 相似文献
6.
Cara Baldwin Lori Bradford Meghan K. Carr Lorne E. Doig Timothy D. Jardine Paul D. Jones 《国际水资源开发杂志》2018,34(2):305-324
Indigenous community members along the Slave River in Canada have voiced their concerns for the health of ecosystems under pressure from resource extraction, hydroelectric development and global climate change. We present a test case of traditional knowledge and scientific results about the spawning and migration patterns of fish in the Slave River and Delta. This dual knowledge system approach elucidates the broader connectivity of local study regions and can improve monitoring programmes by extending beyond the usual context/confines of the present or recent past, increasing the spatial and temporal range of system information. 相似文献
7.
In this paper, we critically examine previous research on rating formats and rater training in the context of performance appraisal. Historically, the goal of this body of research has been to search for ways of maximizing the psychometric quality of performance evaluation data. Our central thesis is that there are a number of avenues for broadening this research. Accordingly, we propose a conceptual model that hopefully serves as a conceptual framework for future work in these 2 traditional performance appraisal research streams. For example, both rating formats and rater training research may be useful for facilitating and improving the feedback and employee development process, as well as reducing the potential existence of rater biases. In addition, format and training research may focus upon ways of enhancing both rater and ratee reactions to the appraisal system. A key feature of our model is the integration of national culture as a moderator of the relations between specific formats, training programs, and various outcomes. We consider both the national culture of raters and ratees, and focus specifically on comparisons between Western and East Asian cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Yu Jin Xiangli Cui Udai P. Singh Alexander A. Chumanevich Brook Harmon Philip Cavicchia Anne B. Hofseth Venkata Kotakadi Brandy Stroud Suresh R. Volate Thomas G. Hurley James R. Hebert Lorne J. Hofseth 《Molecular nutrition & food research》2010,54(10):1506-1514
Chronic inflammation contributes to an increased risk for developing chronic conditions such as cardiovascular disease, diabetes, and cancer. A high “inflammatory load” is defined as elevated inflammation markers in blood or other tissues. We evaluated several markers of systemic inflammation from healthy adults and tested the hypothesis that two formulations of encapsulated fruit and vegetable juice powder concentrate with added berry powders (FVB) or without (FV) could impact markers of inflammatory load. Using a double‐blind, placebo‐controlled approach, 117 subjects were randomly assigned to receive placebo, FV, or FVB capsules. Blood was drawn at baseline and after 60 d of capsule consumption. We measured inflammatory markers (high sensitivity C‐Reactive Protein, Monocyte Chemotactic Protein‐1, Macrophage Inflammatory Protein 1‐β, and Regulated upon Activation, Normal T cell Expressed and Secreted), superoxide dismutase, and micronutrients (β‐carotene, vitamin C, and vitamin E). Results showed Monocyte Chemotactic Protein‐1, Macrophage Inflammatory Protein 1‐β, and RANTES levels were significantly reduced and superoxide dismutase and micronutrient levels were significantly increased in subjects consuming both FV and FVB, relative to placebo. Data suggest a potential health benefit by consuming either formulation of the encapsulated juice concentrates through their anti‐inflammatory properties. 相似文献
9.
10.
Johanson Chris-Ellyn; Lundahl Leslie H.; Lockhart Nancy; Schubiner Howard 《Canadian Metallurgical Quarterly》2006,14(2):99
Ten cocaine-dependent participants were trained to discriminate between intravenous saline and 20 mg/70 kg cocaine. During the first session, saline and cocaine injections were alternated twice, with each separated by 1 hr. The injections were identified by letter codes. During the next 3 sessions, 12 trials were conducted, with saline and cocaine administered 6 times each in pseudorandom order. Thirty minutes following each injection, participants were asked to identify the injection by letter code. Seven of the 10 learned the discrimination (at least 10 trials correct). To evaluate sensitivity, the investigators tested participants with different doses of cocaine in test sessions. In the next phase, methamphetamine (5 and 10 mg/70 kg) and pentobarbital (50 and 100 mg/70 kg) were given intravenously during test sessions to determine whether the discrimination exhibited pharmacological class selectivity. During the evaluation of sensitivity and selectivity, training sessions were interspersed. As dose of cocaine increased, the number of participants identifying the test dose as cocaine increased, demonstrating sensitivity. The higher doses of methamphetamine and pentobarbital substituted for cocaine. The physiological and subjective effects of cocaine and methamphetamine were stimulant-like and dose related. Pentobarbital produced no physiological changes but increased Visual Analog Scale ratings of Sedation, Good Drug Effect, and High. This failure to demonstrate pharmacological selectivity may be related to participants' learning a drug-vs.-no-drug discrimination, and thus it may be necessary to alter training procedures in future studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献