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41.
This multicentre, double-blind, randomized, placebo-controlled, parallel study was designed to evaluate the efficacy of combined oral lysine acetylsalicylate and metoclopramide (LAS-MCP) in the acute treatment of migraine attacks. A total of 266 patients, 18–65 years old, with two to six attacks of migraine with or without aura (IHS criteria) per month were included. The patients had to treat two migraine attacks with LAS-MCP (1620 mg lysine acetylsalicylate-the equivalent of 900 mg aspirin- combined with 10 mg metoclopramide) or placebo. The main outcome measure was headache relief (reduction in headache severity from grade 3 or 2-severe or moderate-to grade 1 or 0-mild or none) 2 h after treatment. LAS-MCP was superior to placebo for headache relief (56% vs 28%) and for the following secondary outcome measures: complete headache relief (18% vs 7%; p < 0.001), nausea (28% vs 44%; p < 0.001), vomiting (3% vs 11%; p = 0.001), use of rescue medication (47% vs 68%; p < 0.001), global efficacy judged as good or excellent (32% vs 14%; p < 0.001). The tolerability was considered as good in 94% of treated attacks in both groups. Combined oral lysine acetylsalicylate and metoclopramide is an effective and well-tolerated acute treatment of migraine attacks.  相似文献   
42.
BACKGROUND: Hepatitis G virus (HGV) is a blood-borne flavivirus that may cause acute and chronic transfusion-transmitted infections. Patients with complement component 1 (C1) inhibitor (C1-INH) deficiency may acquire blood-borne infections through infusion of plasma concentrates. STUDY DESIGN AND METHODS: Serum samples from 84 patients with C1-INH deficiency (19 who received unmodified C1-INH concentrates, 23 who received steam-heated concentrates, and 42 untreated patients) were tested for HGV RNA and hepatitis C virus (HCV) RNA by a nested polymerase chain reaction (PCR). The samples were also tested for antibodies to the E2 envelope protein of HGV (anti-HGV) and to HCV with enzyme-linked immunosorbent assays. RESULTS: Nine (11%) patients had serum HGV RNA; that is, 7 (17%) of 42 patients previously treated with C1-INH concentrates and 2 of 42 previously untreated patients. HGV RNA was as common in the 19 patients treated with unmodified concentrates as in the 23 given steam-heated concentrates (16 vs. 17%, p = 0.60). Anti-HGV was more common among the recipients of unmodified concentrates than among those given steam-heated concentrates (26 vs. 0%, p = 0.014). HCV RNA was more frequently detected in treated patients than in untreated patients (33 vs. 7%, p = 0.005) and in the 19 recipients of unmodified concentrates than in the 23 treated with steam-heated concentrates (58 vs. 16%, p = 0.003). Only one HGV RNA- seropositive patient had elevated serum aminotransferase activity, compared to 11 with HCV RNA. CONCLUSION: HGV was transmitted by both unmodified and steam-heated concentrates, but it caused persistent viremia in a minority of the cases and was rarely associated with liver disease.  相似文献   
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Background and purpose:

Tecarfarin (ATI-5923) is a novel vitamin K epoxide reductase inhibitor that is metabolized by esterase (mainly human carboxylesterase 2) to a single major metabolite, ATI-5900, in rats, dogs and humans. Tecarfarin is not significantly metabolized by CYP450 enzymes. The objective of this study was to test and compare the efficacy of tecarfarin with that of warfarin, when administered either intravenously or once a day orally, to produce stable anticoagulation in beagle dogs.

Experimental approach:

Effects on coagulation were assessed by measuring the activity levels of Factor VII and Factor X and thromboplastin-induced coagulation times, reported as prothrombin time (PT).

Key results:

Continuous intravenous infusions and oral administration of tecarfarin and warfarin caused a dose-dependent decrease in activity of Factor VII and Factor X, and associated increase in PT. Intravenous fresh frozen canine plasma or subcutaneous vitamin K1 treatment reversed the anticoagulant effects of orally administered tecarfarin. Consistent with the inhibitory effects of amiodarone on CYP2C9, co-administration of amiodarone significantly increased the anticoagulation effect of warfarin and plasma warfarin concentrations. In contrast, amiodarone had no effect on the anticoagulation induced by tecarfarin or tecarfarin plasma concentrations in this model.

Conclusions and implications:

Overall, the data presented herein indicate that tecarfarin, via a vitamin K-dependent mechanism, causes changes in key parameters of haemostasis in beagle dogs that are consistent with effective anticoagulation. Compared to warfarin it has a decreased potential to interact metabolically with drugs that inhibit CYP450 enzymes and, therefore, may offer an improved safety profile for patients.  相似文献   
45.
46.
Mean platelet survival and turnover were simultaneously determined with autologous 111In-labeled platelets (111In-AP) and homologous 51Cr- labeled platelets (51Cr-HP) in ten patients with chronic immune thrombocytopenic purpura (ITP). In vivo redistribution of the 111In-AP was quantitated with a scintillation camera and computer-assisted image analysis. The patients were divided into two groups: those with splenic platelet sequestration (spleen-liver 111In activity ratio greater than 1.4), and those with diffuse sequestration in the reticuloendothelial system. The latter patients had more severe ITP reflected by pronounced thrombocytopenia, decreased platelet turnover, and prominent early hepatic platelet sequestration. Mean platelet life span estimated with 51Cr-HP was consistently shorter than that of 111In-AP. Platelet turnover determined with 51Cr-HP was thus over-estimated. The difference in results with the two isotope labels was apparently due to greater in vivo elution of 51Cr. Although the limitations of the techniques should be taken into account, these findings indicate that platelet turnover is not always normal or increased in ITP, but is low in severe disease. We suggest that this may be ascribed to damage to megakaryocytes by antiplatelet antibody. The physical characteristics in 111In clearly make this radionuclide superior to 51Cr for the study of platelet kinetics in ITP.  相似文献   
47.
48.
Background  Pemphigus is an autoimmune disease characterized by the formation of intra-epidermal blisters. Patients develop auto-antibodies against desmoglein 1 and 3 proteins and induce acantholysis.
Objective  This work addresses the issue of whether the Fas pathway mediates acantholysis. Furthermore, the possible suppliers of the Fas pathway were investigated.
Methods  Seventeen biopsies of pemphigus patients were studied by haematoxylin and eosin staining, and apoptosis was defined by TUNEL. The expression of Fas, FasL and caspase 3 was studied by in situ hybridization and immunohistochemistry. Cell infiltrates were studied by immunofluorescence with monoclonal anti-CD3, CD4, CD8, CD19 and CD69.
Results  All of the biopsies showed intra-epidermal blisters, acantholytic cells and inflammatory infiltrates. The blisters expressed Fas, FasL and caspase 3. Cell infiltrates were composed of CD8 and a few CD4+CD69+ cells. Additionally, CD19+ cells were detected. Interestingly, the Fas expression was increased in acantholytic cells and perilesional keratinocytes. Incidentally, these cells exhibited apoptotic features. Interestingly, the CD8 cells expressed FasL.
Conclusion  This paper presents the morphological evidence that apoptosis and acantholysis are linked. Therefore, the Fas pathway is associated with CD8 cells in pemphigus lesions.

Conflicts of interest


None declared.  相似文献   
49.
50.
Farace  MG; Ullu  E; Fantoni  A; Rossi  GB; Cioe  L; Dolei  A 《Blood》1979,53(1):134-141
The poly (A)-containing nuclear RNA from dimethylsulfoxide-induced Friend leukemia cells was fractionated by acrylamide gel electrophoresis in denaturing conditions and analyzed for alpha and beta globin RNA sequences. The results indicate that nuclear RNA contains one species of large-size RNA (0.6 X 10(6) daltons), which is the putative precursor for beta globin mRNA only. In addition, it was shown by electrophoretic analysis that the complex of RNA molecules not resolved by sucrose gradient centrifugation (11S) comprises sequences of decreasing size (0.34, 0.28, and 0.26 X 10(6) daltons), which might be the precursors of alpha and beta globin mRNA.  相似文献   
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