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Because copper-containing ointments are frequently used in anthroposophical medicine, a phase I trial to investigate the cutaneous absorption of copper was conducted. Sixty-one volunteers were randomized [group A: 0.4% copper (I) oxide, 13 men and 18 women (19-55 years); group B: 20% elementary copper, 11 men and 19 women (18-70 years)]. The ointment was applied over a 4-week period followed by a 4-week wash-out phase. Serum and urine copper concentrations were measured by atomic absorption spectrometry and hair copper concentration by inductive coupled plasma mass spectrometry. For statistical analysis, the Student t test for related random samples was used; alpha = 0.05 was chosen for the standard error. In group A, an increase of copper in serum and scalp hair and a decrease in urine were found in the study period. The mean serum concentration in all premenopausal women using oral contraceptives was above normal. In group B, the serum copper concentration increased significantly; in urine, it decreased, and in scalp hair, it remained stable. A higher level of serum copper was found in female volunteers using hormonal contraception. Treatment with the 2 different ointments did not cause toxic irritations on the skin, and it can therefore be deduced that the appropriate application of ointment preparations containing copper in concentrations up to 20% do not present a toxic risk.  相似文献   
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Abstract Background:   Major trauma is the leading cause of mortality and morbidity in children of developed countries. Little research has been done about the health-related quality of life (HRQL) in these children. The aim of the current research is to describe the HRQL of children in the long term after major trauma and to compare it with healthy peers. Methods:   A prospective cohort study of severely injured children (ISS ≥ 16, age < 16 years) who survived the trauma and were admitted to the emergency department of a Dutch level 1 trauma center in 1999 and 2000 (n = 40) was conducted. Between 6 and 8 years after trauma (mean 7.3, SD 0.7 years), outcome was assessed by the Pediatric Quality of Life Inventory (PedsQL 4.0), the EuroQol 5D (EQ-5D), and the EuroQol Visual Analogue Scale (EQ-VAS). Results:   The mean age at the time of the accident was 8.9 years (SD 4.6 years), the mean ISS was 24.9 (SD 11.1), and 25 (63%) cases were male; 28 out of 40 patients were followed up. The mean score on the PedsQL was 81.2 and this did not differ significantly from the norm value. On the EQ-5D, more health problems were reported than in a healthy reference population. The mean EQ-VAS score was 79.4 and was significantly lower than in healthy peers. The lowest scores on the PedsQL and the EQ-VAS were seen in teenagers and in respondents with spinal cord and/or severe cerebral injury. Conclusion:   The results on HRQL in children in the long term after major trauma are inconclusive. Special attention should be given to teenagers with spinal cord or severe cerebral injury who reported the lowest HRQL.  相似文献   
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Human platelets rapidly lose their responsiveness to PAF-acether after blood collection. We collected blood from fasting donors and prepared gel-filtered platelets that remained responsive to PAF-acether for about 6 hours. Log-dose response studies showed bi-phasic aggregation between 20 and 100 nM PAF-acether with secretion of dense-, - and lysosomal granule contents during the second wave of aggregation. Between 0.2 and 10 nM PAF-acether aggregation was weak and no secretion occurred whereas 300 nM PAF-acether or more induced maximal aggregation and secretion. Secretion, however, was never more than 70, 55, and 30% of maximal secretable amount of 5HT, βTG and βN, respectively. Aggregation and secretion were enhanced by fibrinogen (optimal concentration 0.3–0.7 g.l−1), required Ca2+ or Mg2+ but were inhibited when Mg2+ or Ca2+ were present at a concentration of 2 mM or more. These date show that human platelets are almost equally sensitive to PAF-acether as rabbit platelets, and respond with incomplete secretion of dense-, - and lysosomal granule contents.  相似文献   
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Arko FR  Murphy EH  Davis CM  Johnson ED  Smith ST  Zarins CK 《Journal of vascular surgery》2007,46(5):891-6; discussion 896-7
BACKGROUND: It is commonly assumed that the aortic wall deforms uniformly and has uniform wall thickness about the circumference. The purpose of this study was to evaluate the aortic wall motion and thickness in the infrarenal aortic neck of patients with abdominal aortic aneurysms who were undergoing endovascular repair (EVAR) and to compare the dynamic measurements of intravascular ultrasonography with the static measurements of computed tomographic angiography (CTA). METHODS: A total of 25 patients were evaluated before surgery with CTA and three-dimensional reconstructions on a Vitrea workstation, followed by intraoperative assessment of the proximal aortic neck with intravascular ultrasonography (IVUS) before EVAR. Infrarenal aortic neck dimensions on CTA were obtained at 1-mm intervals, but for the purposes of this study all dimensions on CTA were obtained 1 cm below the lowest renal artery. IVUS analysis of the proximal aortic neck was obtained with a 10-second recorded data loop of aortic wall motion. A Digital Imaging and Communications in Medicine viewer was used to view the recorded loop of aortic movement, and each image was captured and then evaluated with a SCION PCI Frame Grabber to determine aortic dimensions and wall thickness. IVUS diameters (250 measurements of each aorta) were recorded through a full continuous cardiac cycle from the epicenter of the lumen (maintaining the left renal vein in its normal anatomic configuration) in an anteroposterior (AP) direction in the area of greatest wall movement and 90 degrees perpendicular to this direction (lateral movement). RESULTS: There was significant variation in infrarenal aortic wall movement about the circumference, with 1.7 +/- 0.6 mm (range, 0.6-2.7 mm) displacement in the AP direction and 0.9 +/- 0.5 mm (range, 0.3-1.5 mm) displacement in the lateral direction (P < .001). Aortic wall thickness was greater in the region of increased AP wall motion than in the area of lesser lateral wall motion (2.3 +/- 0.6 mm vs 1.2 +/- 0.3 mm; P < .001). There was no difference between the IVUS and CTA aortic neck measurements (25.5 vs 25.6 mm; not significant) during the midpoint of the cardiac cycle of IVUS. However, at peak systole, IVUS recorded a greater diameter than CTA (26.4 vs 25.6 mm; P < .001), and at end-diastole, IVUS recorded a smaller diameter than CTA (24.7 vs 25.6 mm; P = .01). CONCLUSIONS: The infrarenal neck of aortic aneurysms deforms anisotropically during the cardiac cycle. The greatest displacement is in the AP direction and corresponds with a significantly greater wall thickness in this area. The magnitude of cyclic change in aortic diameter can be as high as 11%. Further evaluation of proximal aortic neck wall motion after EVAR is warranted to determine the interaction of various stent designs and the aortic wall.  相似文献   
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Introduction: For postgraduate training of doctors there is a need for valid and reliable instruments to assess their daily performance. Various instruments have been suggested, some of which use incognito simulated patients (SPs). These methods are resource intensive. Computerised Case-based testing (CCT) is logistically simpler and may still predict performance well. The research question was to evaluate the predictive validity of CCT for performance.Methods: Seventeen rheumatologists were each visited by eight incognito SPs presenting various rheumatological complaints, and scoring the performance of the rheumatologists using a predefined checklist. From this checklist a panel of experts identified essential items. In addition the rheumatologists sat a CCT test containing 55 cases with a total of 121 items.Results: Negative correlations were found between the SP scores and the CCT scores. This was unexpected. Therefore, background variables on experience were used to compare both methods. The correlation between these and CCT were high and positive and with the SP scores high and negative. This pattern did not differ when using the essential items of the checklist. Reliabilities of the SP scores were markedly high.Discussion: Although CCT was not predictive of SP scores, it was related to working experience. There are good reasons to assume that although SP-scores were more authentic, they were less valid than CCT scores, mainly because they focussed more on thoroughness than on efficiency in data gathering. The results underpin the assumption that for valid performance assessment the most important issue is what information about the candidate is collected and now how authentic the method is.  相似文献   
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