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991.
Can nurses practice caring within a healthcare system that promotes codependency? Caring promotes mutual empowerment of all participants while codependent caring disempowers. Nurses are expected to practice caring with clients, The authors contend, however, that nursing, as historically and currently practiced within bureaucratic/patriarchal organizations, is founded on a vlue system that fosters codependency. Until nursing is practiced within the context of caring organizations and a caring healthcare system, nurses will continue to be powerless to shape their own practice as carers and burnout will continue to be a problem. 相似文献
992.
V. M. Mann J. M. Cooper S. E. Daniel K. Srai P. Jenner C. D. Marsden A. H. V. Schapira 《Annals of neurology》1994,36(6):876-881
Elevated iron levels, enhanced oxidative damage, and complex I deficiency have been identified in the substantia nigra of Parkinson's disease patients. To understand the interrelationship of these abnormalities, we analyzed iron levels, ferritin levels, and complex I activity in the substantia nigra of patients with Parkinson's disease. Total iron levels were increased significantly, ferritin levels were unchanged, and complex I activities were decreased significantly in the substantia nigra samples. The failure of ferritin levels to increase with elevated iron concentrations suggests that the amount of reactive iron may increase in the substantia nigra of Parkinson's disease patients. There was no correlation between the iron levels and complex I activity or the iron-ferritin ratio and complex I activity in the substantia nigra samples. 相似文献
993.
U.M. Hodges BSc Hons MBBS FRCA S. Berg BSc MBBS FRCA S.K. Naik FRCS S. Bower MBChB PhD A. Lloyd-Thomas MBBS FRCA M. Elliot MD FRCS 《Journal of cardiothoracic and vascular anesthesia》1994,8(6)
Modified ultrafiltration after cardiopulmonary bypass in children has been shown to be associated with an increase in arterial blood pressure. As part of a series of studies to investigate the possible causes of this blood pressure elevation, the hypothesis that if filtration was removing a significant amount of fentanyl, then the increase in blood pressure might be due to pain was proposed. Ten children, aged between 0.5 and 9.3 years (median 3.8 years), weighing 5.9 to 25..5 kg (median 15.7 kg), underwent corrective cardiac surgery (incorporating modified ultrafiltration). A standard anesthetic protocol was followed, with up to 78 μg/kg of fentanyl given prebypass for analgesia. After completion of cardiopulmonary bypass, modified ultrafiltration was commenced at 100 mL/min until a hematocrit of 35% was reached. Samples were taken of arterial blood (prefiltration, 3, 10, and 20 minutes postfiltration), the venous reservoir blood (prefiltration) and the filtrate (5 and 10 minutes into filtration). Hemodynamic data were recorded both prefiltration and postfiltration. The hemodynamic data showed the expected rise in both systemic arterial pressure and cardiac index after ultrafiltration. The plasma fentanyl concentrations did not significantly change after ultrafiltration: 1.59 to 12.39 ng/mL (median 6.27 ng/mL) prefiltration and 2.05 to 15.59 ng/mL (6.29 ng/mL) at 3 minutes, 2.22 to 12.64 ng/mL (6.87 ng/mL) at 10 minutes, and 1.83 to 11.52 ng/mL (5.85 ng/mL) at 20 minutes postfiltration. The concentration of fentanyl in the venous reservoir, 2.06 to 11.64 ng/mL (7.04 ng/mL), was not significantly different from the plasma levels. The level of fentanyl in the filtrate was significantly less than the plasma levels, 0.243 to 1.87 ng/mL (0.894 ng/mL) at 5 minutes and 0.385 to 1.688 ng / mL (0.952 ng / mL) at 10 minutes into filtration; (P < 0.02 by the Wilcoxon signed-rank method). The data show that the plasma fentanyl concentration was not significantly reduced by modified ultrafiltration. The fentanyl levels found prefiltration were maintained postfiltration, and the observed changes in systemic arterial pressure were not due to an acute fall in the plasma concentration of analgesic drug. 相似文献
994.
Heat Flow and Distribution during Epidural Anesthesia 总被引:43,自引:0,他引:43
995.
Nitrous oxide does not exacerbate pulmonary hypertension or ventricular dysfunction in patients with mitral valvular disease 总被引:1,自引:0,他引:1
Using the rapid-response thermistor pulmonary artery catheter and transoesophageal echocardiography, this study examined the effects of 100 per cent oxygen, 70 per cent nitrous oxide/30 per cent oxygen, and 70 per cent nitrogen/30 per cent oxygen on the pulmonary circulation and ventricular function in ten patients with pulmonary hypertension. In comparison with baseline measurements, nitrous oxide administration resulted in small but statistically significant (P less than 0.05) changes in mean arterial pressure (76 +/- 14 to 67 +/- 12), mean pulmonary arterial pressure (37 +/- 14 to 33 +/- 13 mmHg), and cardiac output (3.7 +/- 1.4 to 3.2 +/- 1.1 L.min-1). Seventy per cent nitrogen resulted in no significant changes from baseline. The repeat 100 per cent oxygen measurements were nearly identical to the nitrous oxide measurements. It is concluded that nitrous oxide does not exacerbate pulmonary hypertension or ventricular dysfunction during high-dose fentanyl anaesthesia in patients with mitral valvular disease. 相似文献
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