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排序方式: 共有823条查询结果,搜索用时 0 毫秒
821.
Winner P Mannix LK Putnam DG McNeal S Kwong J O'Quinn S Richardson MS 《Mayo Clinic proceedings. Mayo Clinic》2003,78(10):1214-1222
OBJECTIVE: To evaluate the efficacy and tolerability of sumatriptan, 50-mg and 100-mg tablets, compared with placebo for treatment of migraine at the first sign of pain. PATIENTS AND METHODS: Two identical multicenter randomized, double-blind, placebo-controlled, single-attack studies were conducted from May through November 2000 in adults (aged 18-65 years). Patients treated migraine at the first sign of pain, while pain was mild, but not more than 2 hours after onset with oral sumatriptan, 50 mg or 100 mg, or matching placebo. The primary end point was pain-free relief at 2 hours after treatment with 50 mg of sumatriptan compared with placebo. RESULTS: There were 354 patients in study 1 and 337 patients in study 2. Significantly more patients treated with sumatriptan, 50 mg and 100 mg, were completely free from pain 2 and 4 hours after treatment vs patients treated with placebo (at 2 hours, 50% and 57% vs 29%; at 4 hours, 61% and 68% vs 30%; for both, P < .001). Also, significantly more patients treated with sumatriptan, 50 mg and 100 mg, were migraine-free (no pain or associated symptoms) vs those treated with placebo at 2 and 4 hours after treatment (at 2 hours, 43% and 49% vs 24%; at 4 hours, 54% and 63% vs 28%; for both, P < .001). The incidence of overall adverse events was low with the 50- and 100-mg dose of sumatriptan (placebo, 7%; sumatriptan at 50 mg, 14%; sumatriptan at 100 mg, 16%). CONCLUSIONS: Treatment of migraine at the first sign of pain with sumatriptan, 50-mg and 100-mg tablets, provides superior pain-free relief at 2 and 4 hours after treatment compared with placebo. Results of these studies suggest that sumatriptan at 100 mg may be more efficacious than at 50 mg when used in the early treatment paradigm. Because these studies were not powered to detect statistical differences between active doses, studies to investigate this finding are warranted. 相似文献
822.
Granulocyte-macrophage colony-stimulating factor enhances phagocytosis of bacteria by human neutrophils 总被引:19,自引:0,他引:19
In order to determine whether human granulocyte-macrophage colony- stimulating factor (GM-CSF) can enhance phagocytosis, neutrophils were combined with Staphylococcus aureus (S aureus), and both the number of bacteria per neutrophil and the percent of neutrophils phagocytizing were assessed in the absence and presence of GM-CSF. Exposure to GM-CSF did not enable neutrophils to ingest unopsonized bacteria. When bacteria were opsonized with serum, both the number of bacteria per neutrophil and the percent of cells phagocytizing were increased by treatment with GM-CSF. Digestion of extracellular organisms by lysostaphin was used to substantiate phagocytosis. These results indicate that another effect of GM-CSF on the mature neutrophil is the enhancement of phagocytosis. 相似文献
823.
Monocytotropic human immunodeficiency virus type 1 (HIV-1) isolates from patients with acquired immunodeficiency syndrome (AIDS) infect mononuclear phagocytes as well as activated T cells, but do not usually infect immature human myeloid cell lines in vitro. The HL-60 promyelocytic/myeloblastic cell line and the promonocytic line, U937, were susceptible to productive infection by monocytotropic HIV-1 isolates (HIV-1JR-FL and HTLV-IIIBa-L) after treatment with retinoic acid, dimethyl sulfoxide, dibutyryl cAMP, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), or 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Virus production was only detected when these compounds were added before virus infection. Virus replication did not correlate with CD4 receptor expression because undifferentiated HL-60 cells express CD4 and the level of CD4 expression did not increase after differentiation in the presence of retinoic acid, 1,25(OH)2D3, or TPA. A mature monocytic cell line (THP-1) was capable of infection without pretreatment, and treatment with differentiating agents enhanced virus production. A chronically infected cell line (J-HL-60) was isolated after HIV-1JR-FL infection of HL-60 cells treated with retinoic acid. Virus production in this cell line was enhanced more than 10-fold after differentiation in the presence of 1,25(OH)2D3 or TPA. The majority of virus production by 1,25(OH)2D3-treated J-HL-60 cells was associated with the mature, adherent population. Molecular analysis of a cloned line of J-HL-60 showed integration of a single DNA provirus. These results suggest that cellular factors associated with precursor cell differentiation along the myelomonocytic pathway are required for optimal replication of monocytotropic HIV-1 strains in vitro. 相似文献