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INTRODUCTION AND OBJECTIVES: The aim of this study was to analyze the distribution and extent of the myocardium at risk using polar maps obtained with myocardial perfusion SPECT. Myocardial perfusion of territories irrigated by the left anterior descending (LAD), right coronary (RCA) and left circumflex artery (CX) was studied with the help of a technetium-radiolabeled tracer during occlusion of the vessels in the course of percutaneous coronary angioplasty. PATIENTS AND METHOD: We studied 50 patients (24 LAD, 15 RCA and 11 CX). The 99mTc compound was injected immediately after inflation of the balloon, and the artery was occluded for approximately 90 seconds. Tomographic images were acquired, and polar maps showing the extent of the ischemic region (uptake < 50% of maximum) were generated. RESULTS: Mean percentage extent of the ischemic territory was 49.8 +/- 10.3% (minimum 35%, maximum 67%), for the proximal LAD, 39.8 (8.3%) (minimum 20%, maximum 51%) for the mid LAD, 20.3 (7.6%) (minimum 8.3%, maximum 35%) for the RCA, and 21.3 (10.8%) (minimum 10.2%, maximum 30%) for the CX. CONCLUSIONS: The contours and extent of the jeopardized myocardial territory found during coronary occlusion allowed us to generate polar maps that illustrated actual coronary risk. The distribution and extent of the areas at risk differed from those in polar maps generated by most current applications used with myocardial perfusion SPECT.  相似文献   
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Primary cardiac tumors are infrequent, but their clinical presentation is variable and their associated mortality is high. By the time they produce symptoms and the diagnosis is made, they have usually progressed to a large mass causing considerable hemodynamic compromise. Although Doppler echocardiography is the usual technique for the initial diagnosis, magnetic resonance imaging or computed tomography can offer more anatomically useful information. We describe three patients with cardiac angiosarcoma, two in the right atrium and one in the left ventricle, the latter diagnosed by computed tomography-guided biopsy. All three patients underwent surgery, but the short-term course was fatal in all cases.  相似文献   
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The scarce integration and coordination of treatment is considered to be a very important problem in our health system. Can capitation, which means something like "charging a fee on each citizen based on his/her treatment necessities" resolve this problem? Can capitation favor clinical and treatment integration?  相似文献   
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Purpose Imaging with metaiodobenzylguanidine (MIBG) is used for the assessment of neuronal dysfunction in various cardiovascular disorders. Although valuable information is obtained by resting MIBG imaging, it is conceivable that competitive interference with the re-uptake mechanism would exaggerate MIBG defects and might unmask subclinical neuronal dysfunction. Tricyclic antidepressants, such as amitriptyline, have been reported to significantly increase cardiac MIBG washout and inhibit uptake into presynaptic neurons. This study was undertaken to assess whether a single oral dose of amitriptyline could influence cardiac MIBG distribution.Methods Six patients (aged 62–81 years; four males, two females) who had demonstrated a normal cardiac MIBG scan during work-up for movement disorders were studied. The patients underwent a second 123I-MIBG study after oral administration of 25 mg amitriptyline within 1 week. Single-photon emission computed tomography images were acquired at 4 h to assess the regional distribution of MIBG, after generation of polar maps and employing a 20-segment model. Mean percentage of peak activity was calculated for each segment at rest and after amitriptyline administration.Results After amitriptyline administration, there was a decrease in regional MIBG uptake in 10±4 segments per patient [62/120 segments (52%): 37 segments with a 5–10% decrease, 25 segments with a >10% decrease]. This change was statistically significant in lateral (P=0.003), apical (P<0.0001) and inferior (P=0.03) regions.Conclusion A single oral dose of amitriptyline can induce changes in the uptake and retention of cardiac MIBG, indicating the feasibility of use of pharmacological intervention in cardiac neurotransmission imaging.  相似文献   
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BACKGROUND: Primary carcinomas of the fallopian tube are rare and their preoperative diagnosis is difficult due to the lack of specific symptoms. CASES: We present two tumors diagnosed in women 74 and 77 years old. On examination both patients presented as acute pelvic peritonitis with abdominal pain and tenderness with guarding and rebound, as well as fever and leukocytosis. At surgery, a left tubal carcinoma was found in each patient. Marked inflammatory and purulent reaction involving the uterus, the adnexa, and the pelvic peritoneum, and no abnormalities in the digestive tract were identified. A total hysterectomy with bilateral salpingo-oophorectomy was performed in both patients. CONCLUSION: Carcinoma of the fallopian tube should be considered in the differential diagnosis of pelvic peritonitis, a previously poorly reported clinical presentation.  相似文献   
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BACKGROUND: The use of unconventional therapies is growing in western countries. Few studies on their frequency and rationale among multiple sclerosis (MS) patients have been carried out in Europe. OBJECTIVE: To assess the frequency of use of unconventional therapies among MS patients and to explore associated clinical variables. METHODS: Structured questionnaires were given to 380 consecutive patients seen at two hospital-based MS clinics in Barcelona. Clinical and demographical data were recorded at the same time. The questionnaire inquired about demographical features, education, income, use of unconventional therapies for MS and satisfaction with conventional medicine both in general and specifically in MS. RESULTS: The response rate was 50.78%. Forty-one per cent of patients admitted using unconventional therapies during the previous year. Low levels of satisfaction with conventional medicine in general and for MS, and higher Expanded Disability Status Scale (EDSS) scores (EDSS mean: 4.43 in users versus 3.48 in nonusers) were significantly associated with use of unconventional therapies. CONCLUSION: Use of unconventional therapies is not rare among MS patients, and it is associated with high disability levels and dissatisfaction with conventional medicine.  相似文献   
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Postoperative cognitive dysfunction in middle-aged patients   总被引:19,自引:0,他引:19  
BACKGROUND: Postoperative cognitive dysfunction (POCD) after noncardiac surgery is strongly associated with increasing age in elderly patients; middle-aged patients (aged 40-60 yr) may be expected to have a lower incidence, although subjective complaints are frequent. METHODS: The authors compared the changes in neuropsychological test results at 1 week and 3 months in patients aged 40-60 yr, using a battery of neuropsychological tests, with those of age-matched control subjects using Z-score analysis. They assessed risk factors and associations of POCD with measures of subjective cognitive function, depression, and activities of daily living. RESULTS: At 7 days, cognitive dysfunction as defined was present in 19.2% (confidence interval [CI], 15.7-23.1) of the patients and in 4.0% (CI, 1.6-8.0) of control subjects (P < 0.001). After 3 months, the incidence was 6.2% (CI, 4.1-8.9) in patients and 4.1% (CI, 1.7-8.4) in control subjects (not significant). POCD at 7 days was associated with supplementary epidural analgesia and reported avoidance of alcohol consumption. At 3 months, 29% of patients had subjective symptoms of POCD, and this finding was associated with depression. Early POCD was associated with reports of lower activity scores at 3 months. CONCLUSIONS: Postoperative cognitive dysfunction occurs frequently but resolves by 3 months after surgery. It may be associated with decreased activity during this period. Subjective report overestimates the incidence of POCD. Patients may be helped by recognition that the problem is genuine and reassured that it is likely to be transient.  相似文献   
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