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排序方式: 共有1283条查询结果,搜索用时 31 毫秒
1.
Intratemporal vascular tumors: detection with CT and MR imaging 总被引:1,自引:0,他引:1
Lo WW; Shelton C; Waluch V; Solti-Bohman LG; Carberry JN; Brackmann DE; Wade CT 《Radiology》1989,171(2):445-448
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion. 相似文献
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Retrospective analysis of 5037 patients with nasopharyngeal carcinoma treated during 1976-1985: overall survival and patterns of failure. 总被引:33,自引:0,他引:33
A W Lee Y F Poon W Foo S C Law F K Cheung D K Chan S Y Tung M Thaw J H Ho 《International journal of radiation oncology, biology, physics》1992,23(2):261-270
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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WW Thompson 《Transfusion》1993,33(4):333-335
This study was designed to determine the blood donation behavior and attitudes of Hispanic residents of the Lower Rio Grande Valley for the purpose of developing promotional and educational approaches to enhance levels of donor participation. Personal interviews of 545 respondents were conducted in English and Spanish using quota sampling and standard intercept techniques at lower- and middle-income supermarkets in five cities during a payday weekend. A number of research hypotheses were established to test for demographic, behavioral, and attitudinal differences that were observed in donors and nondonors using chi-square analysis and multiple discriminant analysis. After analyzing the difference between Hispanics and non-Hispanics for blood donation rates, all non-Hispanics were eliminated from analysis, and the remaining 419 Hispanics were evaluated on the basis of their donor behavior. Donation among Hispanics was most likely to be by better- educated, English-speaking, higher-job-status individuals who had participated in a blood donation drive. Donors tend to have parent(s) who were donors, and they were also more likely to carry an organ donor card. Donors were found to vary in their behaviors as well as their attitudes and beliefs. Perceptions of a lack of safety in donating, the risk of contracting acquired immune deficiency syndrome, and the financial motivation of donors were most pronounced among Hispanics, which indicated a need for improved education on these issues. 相似文献
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Chun Yuan Jay S. Tsuruda Kirk N. Beach Cecil E. Hayes Marina S. Ferguson Charles E. Alpers Thomas K. Foo D. Eugene Strandness 《Journal of magnetic resonance imaging : JMRI》1994,4(1):43-49
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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L I Golbe A N Lieberman M D Muenter J E Ahlskog G Gopinathan A N Neophytides S H Foo R C Duvoisin 《Clinical neuropharmacology》1988,11(1):45-55
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