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21.
The pH and acid content of 63 glucose-based solutions was measured up to eight years after their expiry. The pH ranged from 2.27 to 4.33. Newly manufactured solutions with 5 per cent or less of glucose which were packaged in plastic bags contained in the order of 0.01 mEq/L of acid per gram of glucose. Solutions with higher glucose concentrations had lower pH and greater acid. As solutions in bags became older, pH decreased and acid increased. In contrast, 25 per cent and 50 per cent glucose solutions in glass containers were much less acid and showed only slight changes with age in pH or acid. The greater rate of acid increase in glucose solutions in plastic bags may be due to the bags being permeable to oxygen and thus allowing slow oxidation of the glucose. 相似文献
22.
Community surveys are increasingly being used as a method of collecting health and lifestyle data. This report describes the use of a simple question on hearing difficulties within such a survey. A systematic sample of 2.5% of the electoral register of the four Parliamentary constituencies of Cardiff, Wales, was drawn. Of the 5145 individuals in the sample, 83% responded. Age and social class explained much of the variability in reported hearing difficulties. A recent fall and cigarette consumption were associated with hearing problems, but the contribution of alcohol consumption while potentially important did not reach statistical significance. This self-administered community survey provided hearing data which are consistent with other specialized studies and is a viable route for the assessment of community needs. 相似文献
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Two experiments were conducted to assess the effects of chronic subcutaneous injections of morphine (1.0 mg/kg) or saline on the pattern and amount of sweetened ethanol and water intake in fluid restricted Long-Evans rats. Following daily injections, 2-h two-bottle choice tests were conducted with water and an ethanol solution (15% ethanol v/v in 5% sucrose w/v). During a 20-day acquisition phase (Experiment 1), ethanol intake patterns and amounts did not differ between saline (n = 6) and morphine (n = 6) groups. Both groups exhibited ethanol intake patterns that decreased exponentially throughout the session suggesting control by fluid restriction procedures. Morphine decreased water intake during initial periods of each session and increased intake during later periods. In Experiment 2, morphine and saline injections were reversed across three phases with the same rats. Morphine increased total ethanol consumption during the first few days of each 15-day phase, but the groups did not differ thereafter, and the initial increases produced no statistically significant group differences. Additionally, morphine augmented ethanol intake in early portions of sessions, while water intake was decreased and increased during early and later portions of each session, respectively. Analysis of the data from the last 5 days of each phase indicated that, when injected with morphine, the group which received saline during acquisition consumed significantly more ethanol solution than the group injected with morphine during acquisition. The effect on patterns of water and ethanol intake were observed, regardless of the drug injected during acquisition.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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P S Withington T R Graham R J Meikle A Allan M T Marrinan C T Lewis 《Journal of medical engineering & technology》1991,15(2):68-71
The development of implantable left ventricular assist devices (LVADs) has almost reached the stage of providing permanent circulatory support in patients who are unsuitable for, or denied, the transplant option. As part of our ongoing haemodynamic evaluation of the Thermo Cardiosystems Inc. (Boston, USA) Mark 14 pneumatic LVAD, pressure-volume loops have been produced from in vitro studies using a modified National Heart Lung and Blood Institute (NHLBI, USA) mock circulatory loop. These studies have demonstrated that during certain phases of the pump cycle non-physiologically high and low pressures are generated within the LVAD. Such abnormal pressures may damage either the bioprosthetic valves in the LVAD or the native heart, and may have adverse effects on cardiovascular control mechanisms. 相似文献
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This article describes a specialized rehabilitation education program, based on adult learning theory, that was developed to promote retention of rehabilitation nurses at MetroHealth Center for Rehabilitation in Cleveland. The curriculum encompasses the skills required to care for rehabilitation patients needing both advanced rehabilitation nursing and critical care nursing. Critical care and rehabilitation nurses collaborated in the presentation of topics and were guided by the course coordinators. Learners were chosen based on experience in rehabilitation, with priority given to those certified in rehabilitation nursing. A variety of evaluation methods elicited positive responses. A 6-month postcourse survey also was completed to assess the long-term effects of the course. 相似文献
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Alan J. Lewis Janet Parker Joanne Diluigi Louis J. Datko Richard P. Carlson 《Immunopharmacology and immunotoxicology》1981,3(3):289-308
Delayed hypersensitivity (DH) was induced in the footpads of mice sensitized to methylated bovine serum albumin (MBSA). The magnitude of this DH response increased with increasing sensitizing concentration of MBSA. Levamisole administered 1 hr prior to MBSA challenge stimulated the DH response and this was optimal using subliminal sensitizing concentrations of antigen. A number of antirheumatic agents, immunomodulators mediator antagonists and antiallergies were subsequently examined using the subliminal sensitizing concentration of MBSA. The same drugs were also evaluated using a normal sensitizing procedure. These studies indicate that the sensitizing concentration of antigen is critical in establishing whether a drug will stimulate or suppress a DH response. 相似文献