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PURPOSE: High cumulative epipodophyllotoxin dosages are reported to be associated with an elevated risk for secondary acute myeloid leukemia (s-AML). This study examined the risk of s-AML following cumulative etoposide doses greater than 2 g/m2 in patients with metastatic germ cell tumors (GCT). PATIENTS AND METHODS: The incidence of s-AML was retrospectively assessed in patients treated within clinical trials between January 1986 and February 1996 at four university centers. All patients received high-dose chemotherapy (HDCT) plus autologous stem-cell support for metastatic GCT, including high cumulative etoposide doses (> 2 g/m2). Minimum patient follow-up was 12 months. Standardized morbidity ratio (SMR) was calculated to estimate the risk associated with high cumulative etoposide doses, as compared with the general population. RESULTS: A total of 302 patients with a median age of 29 years (range, 15 to 55) received a median cumulative etoposide dose of 5 g/m2 (range, 2.4 to 14 g/m2). Four cases of s-AML were observed, which resulted in a cumulative incidence of 1.3% (95% confidence interval [CI], 0.38% to 3.59%) at 52 months of median follow-up (range, 12 to 198). Two cases of secondary myelodysplasia (s-MDS) developed in patients with primary mediastinal GCT. Based on the observed four cases of AML, which are most likely etoposide-related, the risk for developing s-AML (SMR, 160 [95% CI, 43.7 to 411.2]) is significantly increased in comparison to the age-matched general population. CONCLUSION: Due to the low incidence of AML in the general population, the significantly elevated risk for developing s-AML affects only 1.3% of all patients who receive etoposide doses greater than 2 g/m2. HDCT, including etoposide doses greater than 2 g/m2, is associated with an acceptably low incidence of s-AML in patients with advanced GCT. 相似文献
993.
We evaluated a protocol involving two types of choice presentations for assessing leisure choice-making skills of seven older adults with severe disabilities. Initially when presented with pairs of objects representing choices, choice making was validated through demonstration of an object preference. A more complex choice-presentation format was then employed, involving pictures to represent choices. If the preference identified with objects was not demonstrated using pictures, a replication of the object format occurred to ensure changes in choice making using pictures was not due to a preference change. Five participants demonstrated choice-making skills using objects and two demonstrated choices using pictures. These results reflect the importance of assessing choice-making skills prior to presenting choice opportunities. Suggestions for future research focus on expanding the assessment protocol to include a wider array of choice-making skills and training staff to provide choices in a format commensurate with an individual's skill level. 相似文献
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RM Santos JF Tanguay JJ Crowley KR Kruse D Sanders-Millare JP Zidar HR Phillips Y Merhi E Garcia-Cantu R Bonan G C?té RS Stack 《Canadian Metallurgical Quarterly》1998,82(5):673-5, A8
We compared the effect on platelet deposition of the glycoprotein IIb/IIIa receptor antagonist L-703,081, administered locally via a drug delivery stent, with that of a standard metal stent in a canine coronary model. There was a significant reduction in platelet deposition using the L-703,081-impregnated stent compared with the bare metal stent. This study demonstrates an alternative route of delivery of GPIIb/IIIa antagonists with potential advantages over systemic administration. 相似文献
997.
Eight patients with common carotid artery (CCA) occlusion underwent bypass with saphenous vein to either the carotid bifurcation (five), the internal carotid artery (two), or the external carotid artery (one). Indications included ipsilateral transient ischemic attack (two), recent nondisabling hemispheric stroke (two), and transient nonhemispheric cerebral symptoms (two). Two asymptomatic patients with CCA occlusion and contralateral internal carotid stenosis underwent prophylactic revascularization prior to planned aortic surgery. There were no perioperative strokes, occlusions, or deaths. Late ipsilateral stroke occurred in two patients, and one patient had a single transient ischemic attack after 2 years. The four patients with preoperative transient cerebral ischemia experienced relief of their symptoms. Duplex ultrasound is an accurate screening modality for distal patency. Collateral filling of the internal or external carotid artery can usually be demonstrated after aortic arch or retrograde brachial contrast injection. End-to-end distal anastomosis after endarterectomy eliminates the original occlusive plaque as a potential source of emboli. The subclavian artery is preferred for inflow on the left. The CCA origin is easily accessible for inflow on the right. Bypass of the occluded CCA is safe and may be effective in relieving transient cerebral ischemic symptoms, although long-term ipsilateral neurologic sequelae may still occur. 相似文献
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The unstable fracture dislocation of the proximal interphalangeal joint remains a difficult injury to manage despite the availability of a wide variety of treatment options. We describe a simple alternative method of treatment called the doorstop procedure. 相似文献
999.
Laurent Hodges 《Energy》1985,10(12):1273-1276
Analyses of the energy used for winter space heating in residences (and other buildings) often involve only the energy source used in the space-heating system. We demonstrate that serious errors can result from this approach, since the internal heat gains from other energy sources may play an important or dominant role in meeting the heating requirements. It is even possible for energy-conservation measures to lead to apparent increases in energy consumption if the analysis does not include all energy sources. Internal gains should also be considered in analyses of annual energy consumption. 相似文献
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