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Papillary thyroid microcarcinomas (PTMs) are small tumors (< or =1 cm of diameter) that belong to the well-differentiated low-risk carcinomas of the thyroid, which are characterized by benign behavior, probably of little clinical significance, and do not affect patients' survival. They are found in otherwise normal thyroids or in multinodular goiters with a clinical frequency varying substantially according to different series. Sometimes, PTM may be associated with lymph node metastases at presentation and/or locoregional recurrences during follow-up. Distant metastases are extremely rare, but have been reported. Although deaths related to PTM are almost unknown, PTM raises therapeutic implications. This review addresses the issue of definition, treatment, and follow-up of PTM.  相似文献   
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AIM: A classification of ischemic stroke subtypes tailored for individual patients is hard to achieve. In 1993, the Trial of Org 10172 in Acute Stroke Treatment (TOAST) group developed a new system to classify the subtypes of ischemic stroke. In our study we applied the TOAST classification to a group of consecutive patients affected by ischemic stroke, to evaluate outcome and factors associated to each stroke subtype. METHODS: To evaluate the prognosis and the associated factors of ischemic stroke subtypes, we classified according to the TOAST classification a cohort of 159 consecutive patients affected by an acute ischemic stroke. We evaluated neurological deficit at admission by Scandinavian Stroke Scale and scored disability at discharge and 6 months after discharge using the Rankin disability scale. We determined 30 days survival and anamnestically evaluated major vascular risk factors. RESULTS: Patients with cardioembolic stroke and stroke of undetermined etiology had a greater neurological deficit on admission and the worst prognosis either in terms of disability or mortality. Lacunar stroke had the least neurological deficit at admission and the best prognosis. Hypercholesterolemia and smoking were more frequent among patients with large artery atherosclerotic stroke. Hypertension, a history of transient ischemic attack and diabetes were more frequent among patients with lacunar stroke. A weak association with hypertension and smoking was observed for cardioembolic stroke. CONCLUSIONS: The TOAST classification is useful in the clinical setting because it identifies ischemic stroke subtypes with different prognosis and with a different profile of associated factors.  相似文献   
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Cancer cells elaborate metalloproteinases which may play a role in invasion and metastasis. The serum level of the M(r) 72,000 type IV collagenase (MMP-2) was measured in 87 lung cancer patients. Stage IV cancer levels were significantly elevated (P less than 0.0001) compared to normal sera. A significant difference (P less than 0.01) was found between enzyme levels in the presence versus the absence of distant metastasis. For 29 patients treated with combination chemotherapy, a positive relationship was noted between response failure and elevated enzyme levels. Serum metalloproteinase levels may provide information relevant to prognosis as well as treatment decisions.  相似文献   
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BACKGROUND: Coronary vasculopathy is the main cause of cardiac graft failure. Because yearly coronary angiography is invasive in children, a non-invasive method for detecting graft vasculopathy is needed. The aim of this study was to test dobutamine-stress echocardiography in a pediatric population to determine its feasibility, safety and reliability in the detection of graft coronary artery disease. METHODS: Eighteen patients, aged 2 days to 16.8 years at transplantation (mean 8.4 years), underwent 44 dobutamine-stress echocardiography (DSE) exams, at a follow-up of 1.1 to 11.8 years (mean 5.1 years). Selective coronary angiography was performed for comparison. Echocardiographic recordings were obtained in 4 standard views of the left ventricle and measurements carried out within the frames of a 16-segment model. Segmental scores of contractility were obtained for each segment and a total segmental contractility index was calculated at each stage. RESULTS: All patients reached the maximum dose stage. Maximum heart rate was 57% to 90% of predicted maximum. Maximum systolic blood pressure reached 190 mmHg. Segmental scores were normal in 37 and abnormal in 7 cases. Echographic results were concordant with angiography in 82% and discordant in 18% of the cases (4 negative DSEs with minor angiographic lesions, 2 positive DSEs with normal angiography), but there was no significant angiographic lesion with normal DSE. CONCLUSIONS: DSE is a safe and highly feasible non-invasive technique in transplanted children. A normal DSE study successfully predicts the absence of significant coronary artery disease in the post-transplant population.  相似文献   
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