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This is a retrospective analysis of 5037 patients with squamous cell carcinoma of the nasopharynx treated during the years 1976-1985. The stage distribution according to Ho's classification was 9% Stage I, 13% II, 50% III, 22% IV, and 6% Stage V. Only 4488 (89%) patients had a full course of megavoltage radiation therapy. The median equivalent dose to the nasopharyngeal region was 65 Gy and cervical region in node-positive patients 53 Gy. Seventy percent (906/1290) of the node-negative patients had no prophylactic neck irradiation. The overall actuarial 10-year survival rate was 43%, and the corresponding failure-free survival 34%. Altogether, 4157 (83%) patients achieved complete remission lasting more than 6 months, but 53% (2205/4157) of them relapsed after a median interval of 1.4 years. The 10-year actuarial local, regional, and distant failure-free rates were 61%, 64%, and 59%, respectively. Thirty-eight percent (338/891) of all patients with local recurrence achieved second local remission. The local complete remission rate with aggressive re-irradiation alone was 47% (333/706). But 37% (124/338) of the responders recurred the second time. The incidence of distant failure correlated significantly with both the N-stage and the T-stage, with the highest (57%) occurring in patients with N3 disease. The incidence of nodal relapse in node-negative patients was 11% (44/384) among those given prophylactic neck irradiation, but 40% (362/906) among those without. Therapeutic irradiation achieved a complete regional remission rate of 90% (306/339). However, despite successful salvage, these patients had a significantly higher distant failure rate than those without nodal relapse, even if they remained local-failure-free (21% vs 6%). Patients treated during 1981-1985 achieved significantly better treatment results than those treated during 1976-1980, especially in terms of the overall survival (57% vs 47% at 5-year), the overall failure-free survival (42% vs 35% at 5-year), and the local failure-free rate (70% vs 63% at 5-year). The possible contributing factors are discussed.  相似文献   
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Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation.  相似文献   
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Deprenyl, a selective inhibitor of monoamine oxidase, type B, which is free of the "tyramine effect," may ameliorate symptom fluctuations in advanced Parkinson's disease (PD). We randomized 96 patients with marked symptom fluctuations at three centers to receive either deprenyl 5 mg b.i.d. or placebo in parallel fashion in addition to a previously optimized levodopa/carbidopa (Sinemet) regimen. Disability was recorded hourly at home by patients 3 days weekly during the 2-week baseline and the 6-week treatment period. Disability during the "on" state was assessed each week by examination. Mean hourly self-assessment of gait improved in 28 of 50 patients (56%) receiving deprenyl (mean degree of improvement 0.25 points on a 0-2 scale) and in 14 of 46 (30.4%) taking placebo (mean 0.15). Mean hourly overall symptom control improved in 29 (58%) taking deprenyl (mean 0.34) and in 12 (26.1%) taking placebo (mean 0.15) (p less than 0.01 for each parameter). No significant improvement occurred in the objective quality of the "on" state with deprenyl. Mean daily Sinemet dosage decreases were 17% in the deprenyl group and 7% in the placebo group. Adverse effects included nausea, light-headedness, dyskinesias, and hallucinations, all of which abated after the Sinemet dose was reduced. We conclude that deprenyl is of moderate benefit in a majority of patients with symptom fluctuations complicating PD and is generally well tolerated.  相似文献   
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An assessment was made of the value of: (i) the demonstration of intestinal alkaline phosphatase in plasma for the differentiation of intrahepatic from post-hepatic jaundice in 122 jaundiced patients; and (ii) the demonstration of an intermediate molecular mass gamma glutamyltransferase in plasma for the identification of post-hepatic cholestasis in 74 jaundiced patients. The first test had a diagnostic sensitivity of only 32% with a specificity of 86%; the second test had a sensitivity of 50% and specificity of 75%. It is concluded that neither procedure is worth while.  相似文献   
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