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101.
We studied the pharmacokinetics and toxicity of 220 mg/m2 melphalan (HDM 220) followed by autologous stem cell transplantation in 16 patients with advanced haematological malignancies. Pharmacokinetic parameters (mean values of steady-state volume of distribution 14.6 l/m2, total body clearance 313 ml/min/m2, elimination half-life 46 min) were the same as those of 140 or 200 mg/m2 melphalan in previous reports. HDM 220 was feasible. Extramedullary toxicity was mainly W.H.O. grade 4 mucositis (13/16 patients). The median duration of 41 d (10, not reached) of thrombocytopenia <25 × 109/l was long. In multiple myeloma the response rate was 89% in heavily pretreated patients, suggesting that HDM 220 could be considered earlier in the course of the disease as an alternative consolidation therapy.  相似文献   
102.
The nuclear factor-B (NF-B) path-way has been implicated in tumor B-cell survival, growth, and resistance to therapy. Because tumor cells overcome single-agent antitumor activity, we hypothesized that combination of agents that target differentially NF-B pathway will induce significant cytotoxicity. Therapeutic agents that target proteasome and Akt pathways should induce significant activity in B-cell malignancies as both pathways impact NF-B activity. We demonstrated that perifosine and bortezomib both targeted NF-B through its recruitment to the promoter of its target gene IB using chromatin immunoprecipitation assay. This combination led to synergistic cytotoxicity in Waldenstrom macroglobulinemia (WM) cells that was mediated through a combined reduction of the PI3K/Akt and ERK signaling pathways, found to be critical for survival of WM cells. Moreover, a combination of these drugs with the CD20 monoclonal antibody rituximab further increased their cytotoxic activity. Thus, effective WM therapy may require combination regimens targeting the NF-B pathway.   相似文献   
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104.
The role of catecholamines in the genesis of ventricular arrhythmias during the reperfusion period following coronary occlusion remains incompletely understood. An isolated rat heart preparation, free from the influence of autonomic innervation or of circulating catecholamines, was used to assess the effects of beta-adrenoceptor blockade. The hearts were prelabeled with tritiated norepinephrine ( NE3H ), and the total radioactivity and that in NE3H were measured in the effluent coronary flow. The left main coronary artery was ligated for 10 minutes after which reperfusion followed. The liberation of NE3H and the development of ventricular tachycardia and fibrillation were monitored throughout. The cardioselective beta-antagonist agent, acebutolol, in a high concentration (1.1 X 10(-4)M), had good beta-antagonist effect in response to the added isoproterenol (10(-6)M); this concentration of acebutolol also suppressed sustained reperfusion ventricular arrhythmias but unexpectedly increased the release of NE3H . Atenolol, another cardioselective agent, did not prevent reperfusion ventricular arrhythmias even in a high concentration of 40 mg/L (1.5 X 10(-4)M). The d-isomer of propranolol, with poorer beta-antagonist properties than the l-isomer, prevented such ventricular arrhythmias in a concentration of 1.3 X 10(-5)M, which was low when compared to that of atenolol. It is proposed that the beta-antagonist activity of the compounds tested could not explain the inhibition of reperfusion ventricular arrhythmias and that another quality such as membrane-stabilizing activity may be involved.  相似文献   
105.
OBJECTIVE: Carotid arterial compliance is reduced with age in sedentary estrogen-deficient women, contributing to the development of cardiovascular disorders. We determined the effects of regular aerobic exercise, hormone replacement therapy (HRT), and their interaction on carotid arterial compliance using a combination of cross-sectional and intervention study designs. METHODS: Cross-sectionally, we studied three groups of healthy postmenopausal women (50-80 years): 20 sedentary not taking HRT; 24 sedentary taking HRT; and 14 endurance-trained not taking HRT; and 11 sedentary premenopausal controls (20-37 years). In the intervention study, 12 sedentary postmenopausal women (58+/-3 years) who were taking HRT were studied before and after participation in a 3-month aerobic exercise (walking) program. Carotid arterial compliance was measured via simultaneous common carotid artery ultrasound imaging and applanation tonometry. RESULTS: Cross-sectional study. Carotid arterial compliance was lower (P<0.001) in all three postmenopausal groups compared with premenopausal women. Among the postmenopausal groups, arterial compliance was 33-43% higher in the sedentary HRT and endurance-trained women than in their sedentary estrogen-deficient peers. Intervention study. Arterial compliance increased (P<0.05) by approximately 40% to levels that were no longer different than premenopausal women. CONCLUSIONS: HRT use and regular aerobic exercise are associated with augmented carotid arterial compliance in healthy postmenopausal women. Moderate, short-term aerobic exercise can restore carotid arterial compliance in previously sedentary postmenopausal women taking HRT.  相似文献   
106.
A phase III prospective randomized multicenter study was performed to determine whether quinine could improve the response rate of poor-risk acute leukemias (ALs) to standard chemotherapy including a multidrug resistance (MDR)-related cytotoxic agent. The rationale of the study was based on the negative prognostic value of MDR phenotype in ALs and the ability of quinine to reverse this phenotype both in vitro and ex vivo. Three hundred fifteen patients (median age, 49 years; range, 16 to 65) with relapsed (n = 108) or refractory (n = 32) acute myeloblastic leukemia (AML), relapsed (n = 27) or refractory (n = 9) acute lymphoblastic leukemia (ALL), secondary AL (n = 22) or blastic transformation of myelodysplastic syndrome ([MDS] n = 74) or myeloproliferative syndrome ([MPS] n = 43) were randomly assigned to receive mitoxantrone ([MXN] 12 mg/m2/d, days 2 to 5) and cytarabine ([Ara-C] 1 g/m2/12 h, days 1 to 5) alone or in combination with quinine (30 mg/kg/d, days 1 to 5; continuous intravenous infusion beginning 24 hours before MXN infusion). Side effects of quinine were observed in 56 of 161 quinine-treated patients and disappeared in all but four cases after one or two 20% dose decreases. Sera from quinine-treated patients showed increased MXN uptake in an MDR-positive cell line compared with matched sera obtained before quinine infusion. Quinine induced a significant increase in the incidence of nausea, vomiting, mucositis, and cardiac toxicity. A complete response (CR) was observed in 85 of 161 patients (52.8%) from the quinine-treated group versus 70 of 154 patients (45.5%) in the control group (P = .19). The most important differences between quinine and control group CR rates were observed in patients with refractory AMLs and blastic transformation of MDS and MPS. The CR rate was higher in P-glycoprotein-positive cases, although the difference was not significant. Failure of the regimen due to blastic persistence or blast number increase was higher in the control group (61 of 154 patients) than in the quinine group (45 of 161, P = .04). Early death was observed in eight cases (four in each arm) and death in aplasia in 27 cases (20 in quinine group v seven in control group, P = .01). The significant increase of toxicity in the quinine arm could have masked the clinical benefit of MDR reversion in poor- risk ALs.  相似文献   
107.
This retrospective study compares high-dose therapy (HDT) with autologous stem cell transplantation and combined-modality treatment (CT) as a first-line therapy for Hodgkin's disease (HD) for patients with both a clinical stage (CS) IV and/or a mediastinal mass > or =0.45 of the thoracic diameter (MM > or =0.45) at diagnosis, and an incomplete response after the first-line chemotherapy. Data on 42 grafted patients (GP) in Nantes Hospital, France and on 108 combined-modality treated patients (CTP) from two protocols of the GOELAMS group, France (POF 81 and H90) was analyzed. Both groups were comparable except for pulmonary disease in excess in the grafted group (P = 0.01). Among GP, 95% were in complete response at the end of first-line treatment and 77% among CTP. Median follow-up was 53 months (range, 7 to 128 months) for GP and 88 months (range, 25 to 181 months) for CTP. The 5-year freedom from progression (FFP) and event-free survival (EFS) rates were better for GP (87% vs 55% for FFP: P = 0.0004 and 81% vs 51% for EFS: P = 0.0004) whereas the overall survival (OS) rates did not differ significantly (85% for GP vs 71% for CTP: P = 0.06). Similar results were obtained for the groups with a response > or =50% after initial chemotherapy: 91% vs 65% for FFP, P = 0.01; 87% vs 61% for EFS, P = 0.02; and 92% vs 77% for OS, P = 0.2; and for the groups with a response <50%: 80% vs 22% for FFP, P = 0.0003; 72% vs 13% for EFS, P = 0.0001; and 76% vs 46% for OS, P = 0.04. This study shows a better control of the disease with HDT.  相似文献   
108.
109.
Background: In patients with cirrhosis, severe sepsis may stimulate the extrinsic coagulation pathway resulting in thrombin generation and fibrin formation. Aims: To compare 23 patients with severe sepsis to 13 infected patients without severe sepsis and 18 patients without infection. Methods: Zymogen forms of clotting factors involved in the extrinsic pathway (i.e., factors VII+X, V, prothrombin), and the presence of soluble fibrin were assessed. Results: Zymogen forms of clotting factors were significantly lower, while Child–Pugh score and the proportion of patients with soluble fibrin were higher in the severe‐sepsis group than in the other groups. Decreased zymogen levels were independently correlated with an elevated Child–Pugh score and the presence of severe sepsis. In the severe‐sepsis group, after adjustment for the severity of cirrhosis, decreased zymogen levels were associated with significant increases in the relative risk ratios of in‐hospital death. Conclusions: Cirrhotic patients with severe sepsis have decreased blood levels of zymogen forms of factors VII+X, V, and prothrombin, which may be due not only to the severity of cirrhosis but also, at least in part, to the consumption of these zymogens by the extrinsic coagulation pathway.  相似文献   
110.
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