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Prosthetic valve endocarditis is considered to be 15% of all infectious endocarditis in developed countries, more frequently during the first 45 days after surgery. Between 45 and 60% of patients with prosthetic valve endocarditis present periannular involve. The aortic valve injury and early symptoms onset after surgery are related with a higher power of aggressive prosthetic endocarditis invasion. We present the case of a patient affected with early aortic prosthetic valve endocarditis by S. epidermidis with a high aggressive and proliferating course, accompanied by fistula to left atrial, severe aortic regurgitation and left atrial roof rupture detected at the time of surgery, along with interventricular membranous septal defect.  相似文献   
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Cardiovascular manifestations are frequent findings in patients with thyroid hormone disorders. Nitric oxide (NO) plays a key role in vascular, endothelial-mediated relaxation. NO is synthesized from L-arginine by NO synthase, an enzyme inhibited by endogenous compounds, mainly asymmetric dimethylarginine [asymmetric N(G),N(G)-dimethyl-L-arginine (ADMA)]. The aim of our work was to investigate whether plasma L-arginine and dimethylarginine concentrations and NO production are altered in hypo- and hyperthyroid patients, compared with control subjects. L-arginine, ADMA and symmetric dimethylarginine were analyzed by HPLC. NO was measured as plasma nitrite plus nitrate (NO(x)) concentration by a colorimetric method based on Griess reagent. L-arginine, ADMA, and symmetric dimethylarginine plasma levels in the hypothyroid group were similar to those of the control group; whereas in hyperthyroidism, these values were significantly increased. However, the L-arginine/ADMA ratio was decreased in hyperthyroid patients, resulting in diminished NO(x) production. When all subjects were analyzed together, free T(4) levels were directly correlated with ADMA and inversely correlated with NO(x).  相似文献   
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In 112 untreated myeloma patients we have analysed the immunophenotype of plasma cells both by immunofluorescence (IF) and immunocytochemistry (APAAP). Both techniques yielded similar results pointing to an important degree of heterogeneity in antigenic expression not only between different patients but also within the same patient. The expression of CD38 and Han-PC1 antigens (Ags) was almost constant (greater than 90% positive cases), while CD9 was detected in 66% of the cases. On the other hand, less than one third of patients were positive for CD10, CD20 and HLA-DR and generally with a weak expression (less than 30% positive plasma cells). In occasional cases plasma cells were weakly positive for the myelomonocytic markers CD13 (9%), CD15 (25%) and CD14 (6%). The possibility that this heterogeneity might be the result of different stages of differentiation of the neoplastic clone is suggested both by the positive correlation in the expression of some of these antigens (CD10, CD9, CD20, HLA-DR) and by the relationship between CD10 and myeloid antigens with immature plasma cell morphology. Finally, the cALLA antigen does not seem to be of significant value in predicting survival. Moreover, none of the other markers explored showed a clear influence in the course of the disease, although the tendency towards a lower survival found for the CD20+ cases as well as the association of the expression of some antigens and advanced clinical stage, may warrant further studies in a larger series of patients.  相似文献   
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We present a retrospective study of long-term outcome and predictive factors of survival and relapse in 219 paediatric patients with acute lymphoblastic leukaemia (ALL) in second remission. They received allogeneic (allo) or autologous (auto) haemopoietic cell transplantation (HCT) depending on the availability of a matched sibling donor. The probability of event-free survival (EFS) for the total patient group was 0.35+0.03 at 14 years. No significant differences were observed for EFS between allo- and auto-HCT: 0.39+0.05 vs 0.32+0.04 (P=0.43). A better EFS was seen in patients with a late relapse (LR) (P=0.06 and 0.02, for allogeneic and autologous respectively). Significantly better EFS was observed in allo-HCT patients under 10 years of age and in auto-HCT patients with leukocytes at diagnosis below 25 x 109/l and late relapse. Predictive factors of failure in both groups were early relapse (ER), medullary relapse and age over 10 years. The probability of relapse (RP) for the total group of patients was 0.57+0.03, and it was significantly higher in auto-HCT patients: 0.65+0.04 vs 0.42+0.06 (P=0.002). Factors predictive for relapse were medullary and early relapse, auto-HCT and WBC >25 x 109/l at diagnosis.  相似文献   
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