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951.
A Contreras WA Falkler CO Enwonwu EO Idigbe KO Savage MB Afolabi D Onwujekwe TE Rams J Slots 《Canadian Metallurgical Quarterly》1997,12(5):259-265
Currently, much nursing practice is based on limited evidence, for example, small-scale research, case studies and clinical experience. In a mature science this would be undesirable, but nursing is in the early stages of development as a science, and many of its practices depend on relatively informal knowledge. To encourage the spread of potentially valuable ideas, nurses must be willing to share their clinical experience and journal editors should consider publishing this information. High-quality research is essential to the long-term development of 'evidence-based practice', but it is crucial at the present stage of nursing science that we do not become too concerned with perfect research methodology at the expense of good ideas. This particularly applies to tests of statistical significance. If we accept only information that has demonstrated statistical significance, we risk the dismissal of qualitative research and other information which may be extremely valuable but which have not yet been fully investigated. The aim of this paper is to convince practitioners and journal editors that statistical significance is not the only way to judge clinical importance and to suggest that decisions on what should be submitted and accepted for publication should be based on potential clinical relevance as well as statistical analysis. 相似文献
952.
DR Longo RC Brownson JC Johnson JE Hewett RL Kruse TE Novotny RA Logan 《Canadian Metallurgical Quarterly》1996,275(16):1252-1257
OBJECTIVE: To examine the impact of workplace smoking bans on smoking behavior of employees. PARTICIPANTS: A total of 1469 current or former smokers (intervention group) employed in smoke-free hospitals and 920 current or former smokers (comparison group) employed in non-smoke-free workplaces were surveyed to determine smoking behavior. DESIGN: This cross-sectional study is part of a larger, ongoing prospective study. The study design was quasi-experimental. We randomly selected sites consisting of a hospital and a corresponding community. Furthermore, we randomly selected subjects from hospitals and their corresponding communities. MAIN OUTCOME MEASURES: Postban quit ratio and progression along the stages-of-change continuum. METHODS: The Cox proportional hazards model was used to compare the postban quit ratio between the intervention and comparison groups. The Cochran-Mantel-Haenszel analysis of variance statistic was used to compare groups on the stages-of-change variables. RESULTS: Beginning with the smoking ban and continuing for 5 years after implementation, statistically significant differences in the postban quit ratio were observed between employees of smoke-free hospitals who were smokers and counterparts in the community (P<.001). Despite preban differences in smoking intensity, the overall difference in postban quit ratios remained significant even after multivariate adjustment for socioeconomic, demographic, and smoking intensity variables. For those sites that were 5 years postban, the quit ratio was 0.506 in smoke-free workplaces compared with 0.377 in workplaces where smoking was permitted. In all but 1 category, the intervention group was further along the stages-of-change continuum toward quitting smoking than the comparison group (P<.001). CONCLUSION: American hospitals' experiences with smoking bans, which directly affect more than 5 million workers, should be examined by other industries as a method of improving employee health. Workplace smoking bans could also be effective in saving lives, reducing health care costs, addressing safety concerns, and decreasing operating and maintenance expenses of employers. 相似文献
953.
A new Doppler probe inside a needle was evaluated in a group of infants and children to assess its suitability for subclavian venous access. While the efficient use of this device required learning a new technique, we found the device useful to accurately locate the subclavian vein and differentiate it from the artery in all patients weighing more than 3 kg. This device will be most helpful in cases of difficult access, eg, scar from previous access, obesity, or edema. 相似文献
954.
Caffrey MS; Gooley PR; Zhao D; Meyer TE; Cusanovich MA; MacKenzie NE 《Protein engineering, design & selection : PEDS》1997,10(1):77-80
It was shown by Koshy et al. [1990, Proc. Natl Acad. Sci USA, 87, 8697-
8701; 1994, Biochem. J., 299, 347-350] that the substitution of proline 30
by alanine (P30A) of Drosophila melanogaster and rat cytochromes c
exhibited decreased stabilities in both the heme iron-methionine sulfur
(Fe-S) bond and overall protein conformation. Now we have found that the
stability properties of the equivalent mutant of Rhodobacter capsulatus
cytochrome c2 (P35A) are somewhat different. Based on optical and NMR
spectroscopies, the Rb.capsulatus P35A alkaline transition (pKalk) was
found to be unchanged with respect to the wild type, suggesting that the
mutation in Rb.capsulatus cytochrome c2 has little effect on the stability
of the Fe-S bond. However, Rb.capsulatus conformational stability was found
to be decreased by 1.6 kcal/mol in the oxidized state. The difference in
the stability properties of the equivalent proline to alanine substitutions
in various species underscores the importance of studying mutations in more
than one species before drawing generalizations about the role of conserved
residues in protein structure and function.
相似文献
955.
In the last decade it has become evident that many laboratory manipulations, both genetic and environmental, can lead to significant life extension. All or almost all of the observed life-extension phenotypes are associated with increased resistance and/or ability to respond to environmental stress. These observations show dramatically that life span is not maximized. We suggest that latent within many species-perhaps even humans-is the ability for large increases of life expectancy. The striking correlation between the increased stress resistance of all long-lived mutants in C. elegans and other species and the increased resistance of dietary restricted rodents to environmental toxins is consistent with an evolutionary conservation of a life-span maintenance/environmental stress resistance program. We suggest that it may be possible to develop methods for life extension in mammals, including humans, using relatively straightforward manipulations, such as drug treatments. It should be obvious that these findings have tremendous implications for human society at large, and we suggest that the implications of these findings should be explored. 相似文献
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960.
SM Shrestha DM Shrestha TE Gafney KG Maharjan F Tsuda H Okamoto 《Canadian Metallurgical Quarterly》1996,17(4):212-213
Prevalence of hepatitis B and C virus infection amongst intravenous drug users (IDU) in Nepal is not known. To estimate such prevalence 72 IDU individuals were tested for HBV and HCV markers. About 80% of the drug abusers are both anti-HBc (59/72) and anti-HCV (58/72) sero-positive. However persistent infection with hepatitis B, as indicated by positive HBsAg, was detected in only 5.5% (n = 4). Active hepatitis C infection, as indicated by HCV RNA positivity, was documented in 74% (42/58) of those who were anti-HCV positive. Importance of awareness of this observation among the healthcare workers in the prevention of hepatitis C in the community is stressed. 相似文献