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31.
Summary As the pharmacokinetics of a drug may be altered in haemodynamically compromised patients, the plasma concentrations and haemodynamic effects of the calcium entry blocker nimodipine have been examined in patients resuscitated after out-of-hospital cardiac arrest.In 7 patients nimodipine was infused at increasing rates up to 30 µg·kg–1·h–1. The plasma concentrations increased with increasing dose; at the highest dose a mean steady-state plasma concentration of 22.1 ng·ml–1 was obtained, and the mean plasma clearance was 1.4 l·kg–1·h–1. There were no marked changes in mean arterial blood pressure or heart rate.In 9 other patients nimodipine was given as a bolus infusion of 10 µg·kg–1 over 3 min, followed by a continuous infusion of 30 µg·kg–1·h–1. A mean steady-state plasma concentration of 17.6 ng·ml–1 was obtained and the mean plasma clearance was 1.9 l·kg–1·h–1. Heart rate did not change significantly, but the mean arterial blood pressure fell.The data indicate that in patients resuscitated after cardiac arrest, the pharmacokinetics of nimodipine are not markedly different from patients with other conditions, e.g. subarachnoid haemorrhage. However, if a loading dose is given to obtain a steady-state concentration sooner, there will be a fall in arterial blood pressure.  相似文献   
32.
Although nitrous oxide is commonly administered to patients with ischemic heart disease, recent reports suggest that it may induce myocardial ischemia in these patients. The authors compared the effects of nitrous oxide on segmental left ventricular (LV) function and the ST segment of the electrocardiogram with the effects of an equal concentration of nitrogen (crossover design) before the start of surgery in 18 patients who required coronary-artery bypass grafting. The patients studied did not have valvular or LV dysfunction. Anesthesia was induced and maintained with intravenous fentanyl. After endotracheal intubation and 20 min of ventilation with 100% oxygen, either 60% nitrous oxide or 60% nitrogen (randomly assigned) was added to the inspired gas mixture of each patient for 10 min. This was followed by 10 min of 100% oxygen, and then 10 min of 60% nitrous oxide or 60% nitrogen, whichever had not been administered previously. Patients were monitored for myocardial ischemia using a standard 12-lead electrocardiogram and trans-esophageal two-dimensional echocardiography. Surgery did not begin until the study was concluded. No patient experienced an ST segment change greater than 1 mm during the study, and none developed a new segmental wall motion abnormality during inhalation of either nitrous oxide or nitrogen. The authors conclude that nitrous oxide does not induce myocardial ischemia when used as an adjunct to fentanyl anesthesia in patients who have severe coronary-artery disease accompanied by well-preserved valvular and LV function.  相似文献   
33.
Plasma and synovial fluid concentrations of the enantiomers of flurbiprofen were measured in 15 rheumatoid patients receiving 100 mg racemic flurbiprofen twice daily. Pharmacokinetic parameters showed considerable variability within the group of patients, although differences in S(+)/R(-) plasma concentration ratios were small. The average values (+/- s.d.) of oral plasma clearance, volume of distribution and elimination half-life for R(-)-flurbiprofen were 0.075 (+/- 0.066) l min-1, 12.47 (+/- 5.79) l and 138 (+/- 61) min, respectively. The average values (+/- s.d.) of oral plasma clearance, volume of distribution and elimination half-life for S(+)-flurbiprofen were 0.057 (+/- 0.035) l min-1, 12.81 (+/- 4.43) l and 155 (+/- 49) min, respectively. S(+)/R(-) ratios (+/- s.d.) rose from 1.06 (+/- 0.12) to 1.75 (+/- 0.61) at the end of the 12 h interval in plasma and from 1.18 (+/- 0.13) to 1.47 (+/- 0.24) over the measured time course in synovial fluid. Increases in S(+)/R(-) ratios may be clinically important as they demonstrate accumulation of the pharmacologically active species.  相似文献   
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Nowak J  Pols G  Brands W  Rosseel P 《Perfusion》1992,7(1):59-65
This paper reports a clinical evaluation of Bentley's new Univox membrane oxygenator (Bentley Laboratories, Irvine, California). In this new device, the blood flow path is outside the fibre, the incorporated heat exchanger consists of a 22-channel stainless-steel bellows, and the polypropylene fibres are woven into fibre ribbons and wound into each of the bellows channels. In this way, heat and gas transfers take place simultaneously. The priming volume has been reduced to 220ml and the membrane has an effective surface area of 1.6m 2. A BMR 1900 collapsible reservoir (Bentley Laboratories, Irvine, California) was used as a venous reservoir. Ten consenting patients undergoing elective coronary artery bypass surgery were perfused with this new oxygenator. BSA was between 1.7 and 2.11m 2; mean BSA was 1.81. Minimum priming was 1200 ml. The blood-gas results were all within or close to the normal range used in our institution. Acid-base management was performed using alpha-stat regulation and no problems occurred in this series of patients. Average pO 2 was 155mmHG+/-53 with a mean O 2 transfer of 90.7ml and a maximum of 185ml. The heat exchange performance was very good, with a mean coefficient of heat exchange of 0.54+/-0.11 and a maximum of 0.87.  相似文献   
37.
Pharmacokinetics of ciprofloxacin after single oral administration of 250 mg were studied in patients with and without renal failure. Ciprofloxacin concentrations were measured by HPLC. The elimination half-life was 8.7 +/- 0.9 h (mean +/- S.E.M.) in six renal failure patients not on haemodialysis, as compared to 4.4 +/- 0.2 h in six patients with normal renal function. The urinary recovery of unchanged ciprofloxacin was 5.3 +/- 1.7% of dose over 24 h in the renal failure patients, as compared to 37.0 +/- 3.7% in the patients with normal renal function. In haemodialysis patients, the half-life was 5.8 +/- 0.9 h on an interdialysis day, and 3.2 +/- 0.4 h during haemodialysis.  相似文献   
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Background  

The relationship between poor health and unemployment is well established. Health promotion among unemployed persons may improve their health. The aims of this study were to investigate characteristics of non-participants and drop-outs in a multidisciplinary health promotion programme for long-term unemployed persons with health complaints, to evaluate changes in physical health among participants, and to investigate determinants of improvement in physical health.  相似文献   
40.
BACKGROUND: In the context of the increasing interest in the study and assessment of emotional abilities in psychology, we translated into French and evaluated the construct validity of the emotional intelligence inventory (EII) designed in English [Psychol Rep; 88 (2001):353-64]. This self-rating scale is modelled along the theoretical constructs of the Mayer, Caruso and Salovey's model [Intelligence; 27 (1999):267-98]; it comprises 41 items tapping the four following factors: (1) empathy; (2) utilization of feelings, (3) handling relationships and; (4) self-control. METHODS: One thousand three hundred and thirty-five students (42.7% men) with a mean age of 19.6 years and affiliated to several school and faculties participated to this Belgian interuniversity study. They were administered the French version of the EII, as well as a series of related questionnaires. Confirmatory factor analyses (CFA) were applied to these data and various fit indices examined in order to assess the factorial adjustment to the data of the four-factor a priori structure. RESULTS: CFA did not support the original 41-item four-factor structure for the scale in French, but a good statistical fit to the data could be obtained with the reduction of the scale to 20 items. The content of the resulting item set, keeping Tapia's four factors, encourages a revision of the domain covered by the subscales. CONCLUSION: Further efforts should be directed at assessing the content validity of the proposed revised scale as a reliable tool in measuring emotional intelligence by self-report.  相似文献   
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