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111.
A Brainsky RH Fletcher HA Glick PN Lanken SV Williams HL Kundel 《Canadian Metallurgical Quarterly》1997,25(5):801-805
OBJECTIVE: To determine the effects and net costs of routine chest radiographs in a medical intensive care unit (ICU). DESIGN: A prospective, cohort study. A survey of experts in critical care and pulmonary diseases was undertaken to assess the effect of routine radiographs on patient management. SETTING: Medical ICU of a university hospital. PATIENTS: Eighty randomly selected patients admitted to a medical ICU. Two hundred fourteen experts were surveyed; 118 (55%)/214 responded. MEASUREMENTS AND MAIN RESULTS: Daily interviews with medical ICU clinicians were conducted to assess the radiographic findings in the routine radiographs and actions taken based on these findings. Experts evaluated the findings, their importance, the actions taken, and the probability of complications if the actions had not been taken at that time. Experts also predicted increases in length of stay associated with these complications. Presence of radiographic findings, changes in management because of the findings, net costs of routine chest radiographs, cost per finding that prompted an action, and expected changes in length of stay resulting from the actions were also assessed. Seventy-two (33%) of 221 routine radiographs (95% confidence interval: 25% to 39%) had findings, of which 44 (61%) were judged important, and 18 (8%, 95% confidence interval: 5% to 12%) prompted actions. Experts predicted that each action averted, on average, 2.1 +/- 1.7 days (SD) in the medical ICU. Mean savings per routine radiograph was $98. Net savings from routine chest radiographs remained after sensitivity analysis for expected change in length of stay, percentage of patients with routine radiographs, and percentage of routine radiographs that produce changes in management. CONCLUSION: The policy of obtaining routine chest radiographs in the medical ICU is effective and results in net savings. 相似文献
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SJ Vacha GD Bennett SA Mackler MJ Koebbe RH Finnell 《Canadian Metallurgical Quarterly》1997,21(3):212-222
Neural tube defects (NTDs) are among the most common congenital malformations, affecting approximately 1 per 1,000 liveborn infants in the United States [Nakano, 1973; Richards et al., 1972]. Maternal exposure to hyperthermia, either through recreational sources or due to an infectious agent, is thought to account for approximately 10% of observed NTD cases. The specific genes conferring susceptibility or resistance to hyperthermia-induced NTDs have not been identified. This study used differential display-polymerase chain reaction (DD-PCR) to characterize alterations in gene expression in the anterior embryonic neural tube of two highly inbred murine strains (SWV/Fnn, LM/Bc/Fnn) known to differ in their genetically determined susceptibility to heat-induced NTDs. Herein, we report the neural tube-specific differential expression of the growth arrest specific (gas 5) gene in the highly susceptible SWV/Fnn strain during neural tube closure (NTC). Although the expression of gas 5 did not appear to be altered by the teratogenic heat treatment, its spatial and strain-specific pattern of expression makes it an excellent candidate gene responsible for the observed genetic differences in NTD susceptibility between these two inbred murine strains. 相似文献
114.
Recent finding suggest that many fetuses have to adapt to a limited supply of nutrients and in doing so they permanently change their physiology and metabolism. These 'programmed' changes may be the origins of a number of diseases in life, including coronary heart disease and the related disorders stroke, diabetes and hypertension. 相似文献
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HS Cronjé P Divall RH Bam BF Cooreman I Niemand 《Canadian Metallurgical Quarterly》1997,41(4):1091-1094
BACKGROUND: Mesothelial integrity is essential for the prevention of pericardial adhesions. This study was performed to determine the effect of physical protection of the pericardium on mesothelial integrity. METHODS: A pericardial biopsy specimen was obtained at the time of pericardiotomy (0 minutes) in 10 patients undergoing a cardiac operation for the first time. The left free edge of the pericardiotomy was plicated inward to protect the mesothelium. Biopsy specimens were obtained from the protected and unprotected pericardium at 45 and 90 minutes after the start of extracorporeal circulation. Mesothelial integrity and the local inflammatory response were then assessed and graded histologically. RESULTS: The mesothelium was found to be present in the protected specimens at 0, 45, and 90 minutes, but it was found to be denuded in the unprotected specimens (p = 0.003 at 45 minutes; p = 0.004 at 90 minutes). Local inflammation was totally established in both the protected and unprotected specimens at 45 minutes. CONCLUSIONS: Physical agents appear to be the main factor that is damaging to the pericardial mesothelium, and this is an important concept to be taken into consideration when designing a method to prevent pericardial adhesions. 相似文献
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