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661.
The aim of the present randomized trial was to compare high-dose therapy (HDT) with continued conventional chemotherapy in patients with multiple myeloma (MM) who responded to the initial treatment. From May 1994 to October 1999, 216 patients (122 men/94 women; stage II or III; Eastern Cooperative Oncology Group [ECOG] score less than 3) entered the study. Initial chemotherapy consisted of 4 cycles of alternating vincristine, BCNU, melphalan, cyclophosphamide, prednisone/vincristine, BCNU, Adriamycin, dexamethasone (VBMCP/VBAD). Responding patients were randomly assigned to receive 8 additional cycles of VBMCP/VBAD, intensification with melphalan 200 mg/m2, or melphalan 140 mg/m2 plus 12 Gy fractionated total body irradiation (TBI). One-hundred sixty-four patients were randomly assigned, 83 to continued chemotherapy and 81 to HDT. The complete remission (CR) rate was significantly higher with HDT (30% vs 11%; P = .002). However, progression-free survival (PFS) was not significantly different between HDT and conventional therapy (median, 42 vs 33 months; P = not significant [NS]), and overall survival (OS) was similar in both groups (median, 61 vs 66 months). Finally, survival after relapse was identical in the 2 arms (15.9 vs 16.4 months). In conclusion, these results show that HDT intensification, when given to myeloma patients who have responded to the initial chemotherapy, significantly increases the CR rate but has no significant impact on PFS or OS.  相似文献   
662.
Binding of urokinase-type plasminogen activator (uPA) to its glycosylphosphatidylinositol-anchored receptor (uPAR) initiates signal transduction, adhesion, and migration in certain cell types. To determine whether some of these activities may be mediated by associations between the uPA/uPAR complex and other cell surface proteins, we studied the binding of complexes composed of recombinant, soluble uPA receptor (suPAR) and single chain uPA (scuPA) to a cell line (LM-TK- fibroblasts) that does not express glycosylphosphatidylinositol (GPI)-anchored proteins to eliminate potential competition by endogenous uPA receptors. scuPA induced the binding of suPAR to LM-TK- cells. Binding of labeled suPAR/scuPA was inhibited by unlabeled complex, but not by scuPA or suPAR added separately, indicating cellular binding sites had been formed that are not present in either component. Binding of the complex was inhibited by low molecular weight uPA (LMW-uPA) indicating exposure of an epitope found normally in the isolated B chain of two chain uPA (tcuPA), but hidden in soluble scuPA. Binding of LMW-uPA was independent of its catalytic site and was associated with retention of its enzymatic activity. Additional cell binding epitopes were generated within suPAR itself by the aminoterminal fragment of scuPA, which itself does not bind to LM-TK- cells. When scuPA bound to suPAR, a binding site for alpha 2-macroglobulin receptor/LDL receptor-related protein (alpha 2 MR/LRP) was lost, while binding sites for cell-associated vitronectin and thrombospondin were induced. In accord with this, the internalization and degradation of cell-associated tcuPA and tcuPA-PAI- 1 complexes proceeded less efficiently in the presence of suPAR. Further, little degradation of suPAR was detected, suggesting that cell- bound complex dissociated during the initial stages of endocytosis. Thus, the interaction of scuPA with its receptor causes multiple functional changes within the complex including the dis-appearance of an epitope in scuPA involved in its clearance from the cell surface and the generation of novel epitopes that promote its binding to proteins involved in cell adhesion and signal transduction.  相似文献   
663.
PurposeTo evaluate the association of body mass index (BMI) and physical activity (PA) during adulthood and at the age of 18 years with risk of non-Hodgkin lymphoma (NHL).MethodsWe enrolled 950 newly diagnosed NHL patients and 1146 frequency-matched clinic-based controls. Height, weight, and PA (recent adult and at the age of 18 years) were self-reported. Odds ratios (ORs), 95% confidence intervals, and tests for trend were estimated using unconditional logistic regression adjusted for age, gender, and residence.ResultsBMI at the age of 18 years was associated with an increased NHL risk (OR, 1.38 for highest vs. lowest quartile; p-trend = .0012), which on stratified analysis was specific to females (OR, 1.90; p-trend = .00025). There was no association of adult BMI with NHL risk. Higher PA in adulthood (OR, 1.03; p-trend = .85) or at the age of 18 years (OR, 0.88; 95% confidence interval, 0.72–1.07) was not associated with risk, but there was an inverse association for adult PA that was specific to females (OR, 0.71; p-trend = .039). Only BMI at the age of 18 years remained significantly associated with NHL risk when modeled together with PA in adulthood or at the age of 18 years. There was little evidence for heterogeneity in these results for the common NHL subtypes.ConclusionsEarly adult BMI may be of greatest relevance to NHL risk, particularly in females.  相似文献   
664.
Basilar artery fenestration aneurysms are very rare and endovascular management of large and complex aneurysms is extremely challenging. Most of these type of cases are managed with stent assisted coiling, dual flow diverters (FD) and single FD with additional coiling of aneurysm and occlusion of one of the vertebral artery. Here, we report a case of large complex basilar artery fenestration aneurysm successfully treated with single FD using novel technique called “crossing flow diverter technique” without any additional coiling of aneurysm or occlusion of vertebral artery. Using this technique cost of procedure and procedural complexity inherent with other above mentioned techniques can be significantly reduced.  相似文献   
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