Shape, margin, echogenicity, and presence of calcification are helpful criteria for the discrimination of malignant from benign nodules; the diagnostic accuracy of US criteria is dependent on tumor size.

Objective-Increased risk of cardiovascular disease in patients with chronic renal failure (CRF) has been explained by accelerated atherosclerosis and impaired angiogenesis, in which endothelial progenitor cells (EPCs) may play key roles. We hypothesized that altered EPC biology may contribute to the pathophysiology of CRF. Methods and Results-EPCs were isolated from CRF patients on maintenance hemodialysis (nϭ44) and from a normal control group (nϭ30). CRF patients showed markedly decreased numbers of EPC (44.6%) and colonies (75.3%) when compared with the controls (PϽ0.001). These findings were corroborated by 30.5% decrease in EPC migratory function in response to vascular endothelial growth factor (VEGF) (Pϭ0. T he lifespan of patients with chronic renal failure (CRF) is reduced, and coronary artery disease is the most important cause of morbidity and mortality in these patients. 1,2 Even the results of therapeutic strategies such as percutaneous coronary intervention and bypass surgery have shown poor procedural success rates and dismal long-term eventfree survival in CRF patients. 3,4 Most of the increased cardiovascular morbidity and mortality in CRF has been accounted for by the rapid progression of atherosclerosis, which is clinically shown to be accelerated in CRF. 5,6 Experimental studies have also shown that even mild renal dysfunction causes a dramatic acceleration of atherosclerosis. 7 Angiogenesis, which is an essential compensation for myocardial ischemia, is also impaired in CRF. 8 However the mechanism underlying the acceleration of atherosclerosis and impaired angiogenesis by CRF has not been examined closely. Although the phenomenon has been partially explained by the higher prevalence of established risk factors in CRF, such as hypertension, abnormal carbohydrate metabolism, and increased low density lipoprotein (LDL) cholesterol, the extent and severity of cardiovascular disease is clearly disproportionately high relative to the underlying risk factor profile. 9,10 Recent studies have identified that normal adults have a small amount of circulating endothelial progenitor cell (EPC) in the peripheral blood. In response to cytokine stimulation and ischemic insult, these cells are mobilized from bone marrow, home to the ischemic tissue, and contribute to neovascularization and angiogenesis. 11-14 Moreover, EPC is regarded to have a key role in the maintenance of vascular integrity and to act as "repair" cells in response to the endothelial injury, 15,16 which has been regarded as an initial step in atherosclerosis and a result of the actions of various cardiovascular risk factors. 17 Current data suggest that decrease in circulating EPC contributes not only to impaired angiogenesis but also to the progression of atherosclerosis, 18 and patients at risk for coronary artery disease have a decreased number of circulating EPC with impaired activity. 19 -22 Therefore, we reasoned that EPC, which is critical for neovascularization and the maintenance of vascular integrity, Methods Study SubjectsWe...

RS was independently associated with good outcomes without increasing symptomatic intracranial hemorrhage or mortality. RS seemed considered in MT-failed internal carotid artery or middle cerebral artery M1 occlusion.