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981.
BACKGROUND: Metal skin clips are used in surgery. They may contain metals that might cause allergic reactions and delayed wound healing. METHODS: The metal composition of 18 different surgical clamps was examined. The allergy status of 184 patients was determined by patch tests and was correlated with the clinical outcome of wound healing after application of skin clips. RESULTS: Skin clips contained chromium, nickel, molybdenum, cobalt, and titanium in concentrations high enough to cause allergic reactions. Eighteen percent of the men and 23% of the women were sensitive to nickel and 16% of the men to chromium. We found a positive correlation between the grade of nickel allergy and the reaction to the skin clips. CONCLUSIONS: Our study suggests that allergic reactions and delayed wound healing can be caused by the use of surgical skin clips. Therefore skin clips are not recommended for patients with a history of contact dermatitis to metals and/or atopy. 相似文献
982.
HJ Bernsen PF Rijken JP Peters H Bakker AJ van der Kogel 《Canadian Metallurgical Quarterly》1998,43(3):570-5; discussion 575-6
OBJECTIVE: The purpose of this study was to examine the delayed effects of antivascular endothelial growth factor treatment on tumor growth and vascularity in a subcutaneous mouse tumor model of human glioblastoma. METHODS: Antivascular endothelial growth factor antibody treatment was administered for a period of 6 weeks, to suppress tumor growth. To detect late vascular effects, tumor vascular parameters for treated tumors and control tumors were analyzed 4 weeks thereafter. By that time, tumors had grown to adequate sizes (diameter, 8-10 mm) for comparison with untreated control tumors. Vascular parameters were quantified by using an image-analysis system. RESULTS: Vascular density was significantly lower in antivascular endothelial growth factor antibody-treated tumors, compared with control tumors of similar size. The vascular architecture of treated tumors was also distinctly different, compared with control tumors, showing larger but sparser vessel structures. CONCLUSION: These findings suggest that antiangiogenic therapy may have a prolonged effect on the vascular architecture of certain tumors, resulting in enduring changes in the tumor vessels. Because tumor vasculature plays an important role in the sensitivity to various treatment modalities, these changes are likely to influence the responses of these tumors to further therapy. 相似文献
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PF Rosier JJ de la Rosette MJ de Wildt FM Debruyne H Wijkstra 《Canadian Metallurgical Quarterly》1996,15(1):1-10; discussion 10-5
Analysis of the pressure/flow relation renders objective and detailed information on bladder outlet obstruction. The benefit of pressure/flow analysis for clinical and fundamental research questions, however, cannot be acknowledged without comparison of the different methods that exist. We compared one parameter analysis (URA) with two parameter (PURR) analysis in 99 consecutive patients with benign prostatic enlargement. The normal (instantaneous intrapatient) variability of both the PURR parameter Pvoidmin (minimal pressure during voiding) and the URA is approximately 10-15 cm H2O. Within these limits agreement between the two methods of analysis in the quantification of (minimal) outlet obstruction was observed in about 50% of the cases. However, when Qmax is less than 6 ml/s (in 49.5% of the patients) the URA number exceeds the value Pvoidmin in 96% of the cases. Predominantly this is caused by the fact that in the majority of these cases the type of bladder outlet obstruction is more constrictive than the URA curve, based on Pdet at Qmax indicated. In patients with a low flow rate and/or a constrictive type of obstruction, the Pvoidmin resulting from PURR analysis indicates a lower minimal pressure during voiding compared to URA. 相似文献
984.
L Bolognese D Antoniucci D Rovai P Buonamici G Cerisano GM Santoro C Marini A L'Abbate PF Fazzini 《Canadian Metallurgical Quarterly》1996,28(7):1677-1683
OBJECTIVES: We sought to compare myocardial contrast echocardiography with low dose dobutamine echocardiography for predicting 1-month recovery of ventricular function in acute myocardial infarction treated with primary coronary angioplasty. BACKGROUND: The relation between myocardial perfusion and contractile reserve in patients with acute myocardial infarction, in whom anterograde flow is fully restored without significant residual stenosis, is still unclear. METHODS: Thirty patients with acute myocardial infarction treated successfully with primary coronary angioplasty underwent intracoronary contrast echocardiography before and after angioplasty and dobutamine echocardiography 3 days after the index infarction. One month later, two-dimensional echocardiography and coronary angiography were repeated in all patients and contrast echocardiography in 18 patients. RESULTS: After coronary recanalization, 26 patients showed myocardial reperfusion within the risk area, although 4 did not. At 1-month follow-up, all patients had a patient infarct-related artery without significant restenosis. Both left ventricular ejection fraction and wall motion score index within the risk area significantly improved in the patients with reperfusion ([mean +/- SD] 38 +/- 8% vs. 48 +/- 12%, p < 0.005; and 2.35 +/- 0.5 vs. 2 +/- 0.6, p < 0.001, respectively), but not in those with no reflow. Of the 72 nonperfused segments before angioplasty, 27 showed functional improvement at follow-up. Myocardial contrast echocardiography had a sensitivity and a negative predictive value similar to dobutamine echocardiography in predicting late functional recovery (96% vs. 89% and 89% vs. 93%, respectively), but a lower specificity (18% vs. 91%, p < 0.001), positive predictive value (41% vs. 86%, p < 0.001) and overall accuracy (47% vs. 90%, p < 0.001). CONCLUSIONS: Microvascular integrity is a prerequisite for myocardial viability after acute myocardial infarction. However, contrast enhancement shortly after recanalization does not necessarily imply a late functional improvement. Thus, contractile reserve elicited by low dose dobutamine is a more accurate predictor of regional functional recovery after reperfused acute myocardial infarction than microvascular integrity. 相似文献
985.
SP Bradley WR Auger KM Moser PF Fedullo RN Channick CM Bloor 《Canadian Metallurgical Quarterly》1996,78(5):584-587
Right ventricular free wall biopsy specimens in 40 patients undergoing surgery for relief of chronic thromboembolic pulmonary hypertension were normal in 5%, disclosed only myocyte hypertrophy in 80%, mild focal fibrosis in 12.5%, and myocarditis in 2.5%. There was no relation between postsurgical functional or hemodynamic outcomes and the presence of focal fibrosis. 相似文献
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