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81.
P M Ellis R Beeston C J McIntosh C E Salmond R R Cooke 《Acta psychiatrica Scandinavica》1992,86(2):108-112
Decreased binding of tritiated imipramine to platelets has been considered to be a potential biological marker of depression. However, it has been unclear how binding values alter during treatment and recovery. This study investigated imipramine binding parameters and depressive symptoms in 25 patients suffering from major depression at entry to the study and 1, 3 and 6 months later. Although the initial Bmax values were significantly lower in the depressed patients than in healthy subjects, it was not possible to establish a clear relationship between recovery from depression and Bmax. The power of this study to detect an effect of at least 10% of the variance in Bmax due to factors related to recovery from depression was 0.78. 相似文献
82.
目的 :了解活化血小板葡萄糖摄取过程及血小板膜整合素对其影响 ,探讨整合素与血小板能量代谢的关系 ,旨在研究血小板能量代谢涉及的信号传导 ,并为目前临床应用血小板膜糖蛋白Ⅱb/Ⅲa(GPⅡb/Ⅲa)单抗抗血小板活化提供新的理论依据。方法 :用液态闪烁计数方法检测在血小板膜糖蛋白Ⅱb/Ⅲa单抗 10E5及血小板整合素αυβ3 单抗 6 0 9干预与否情况下凝血酶激活后血小板摄取氚标 2 脱氧葡萄糖 ([3 H]2 DG)率。结果 :在生理浓度范围内活化血小板 [3 H]2 DG摄取率较静息时明显升高 ,单抗 10E5可充分阻断活化血小板葡萄糖摄取 ,单抗 6 0 9可部分阻断。结论 :整合素家族单抗可抑制血小板激活后葡萄糖摄取 ,提示其可能参与血小板能量代谢信号传导过程 ,并可能以GPⅡb/Ⅲa为主 相似文献
83.
84.
V. EVANGELISTA G. DE BERARDIS† L. TOTANI F. AVANZINI‡ C. B. GIORDA§ L. BRERO¶ G. LEVANTESI G. MARELLI†† M. PUPILLO‡‡ G. IACUITTI‡ G. POZZOLI‡ P. DI SUMMA¶ E. NADA§ G. DE SIMONE G. DELL'ELBA C. AMORE S. MANARINI R. PECCE A. MAIONE† G. TOGNONI† A. NICOLUCCI† 《Journal of thrombosis and haemostasis》2007,5(11):2197-2203
BACKGROUND: The percentage of diabetic patients who do not benefit from the protective effect of aspirin is larger than in other populations at cardiovascular risk. OBJECTIVE: We compared the ability of aspirin to suppress TxA2 and platelet activation in vivo, in type-2 diabetics vs. high-risk non-diabetic patients. METHODS: Urinary 11-dehydro-TXB2, plasma sCD40 L, and sP-selectin were measured, together with indices of low-grade inflammation, glycemic control, and lipid profile, in 82 patients with type-2 diabetes and 39 without diabetes, treated with low doses of aspirin. RESULTS: Urinary 11-dehydro-TxB2, plasma sCD40L and sP-selectin were significantly higher in diabetics than in controls: [38.9 (27.8-63.3) vs. 28.5 (22.5-43.9) ng mmol(-1) of creatinine, P = 0.02], [1.06 (0.42-3.06) vs. 0.35 (0.22-0.95) ng mL(-1); P = 0.0001], [37.0 (16.8-85.6) vs. 20.0 (11.2-35.6) ng mL(-1), P = 0.0001], respectively. The proportion of individuals with diabetes increased across quartiles of 11-dehydro-TxB2, sCD40L, and sP-selectin, with the highest quartiles of 11-dehydro-TxB2, sCD40L and sP-selectin, including 66%, 93.3%, and 93.3% of individuals with diabetes. Markers of platelet activation positively correlated with indices of glycemic control but not with markers of low-grade inflammation. CONCLUSIONS: Platelet dysfunction associated with insufficient glycemic control, may mediate persistent platelet activation under aspirin treatment. 相似文献
85.
Alexey V. Mazurov Dimitry V. Vinogradov Svetlana G. Khaspekova Anatoly V. Krushinsky Ludmila V. Gerdeva Sergei A. Vasiliev 《European journal of haematology》1996,57(1):38-41
Abstract: Patient B.G. is a 29-yr-old female with a lifelong bleeding disorder characterized clinically by a highly increased bleeding time, menorrhagias, long-lasting bleeding after cuts and tooth extractions and large post-traumatic haematomas. Her coagulation tests were within normal range, platelet count was 140,000–160,000 per μl, but platelet function was impaired as demonstrated by the absence of collagen-induced aggregation, although no abnormalities were detected in aggregation response to ADP and ristocetin. Morphologically her platelets were characterized by gigantic size – average profile area was about 2.5 times higher than that of control donors, and severe deficiency of α-granules – only 16% of their number in control donors. These features taken together indicated the diagnosis of grey platelet syndrome. As has been shown by quantitative immunoblotting, patient's platelets contained small amounts of α-granule membrane protein P-selectin – about 15% of that in control donors. The content of plasma membrane glycoproteins IIb–IIIa and Ib was not reduced, suggesting the specific deficiency of α-granule membrane protein. Thus, B.G. is the second patient described in the literature (see also Lages et al, J Clin Invest 1991: 87: 919–929) with combined deficiency of α-granules and P-selectin. 相似文献
86.
87.
支气管哮喘患者早期病理形态学改变 总被引:3,自引:1,他引:2
目的:应用电镜对支气管哮喘患者以气管粘膜进行观察,了解支气管病理形态学改变。方法:对持续咳嗽3 ̄12个月的12例哮喘患者,1周内未使用类固醇、妥痉平湍及抗组织胺类药物,行支气管镜常规检查,每例患者取2 ̄3块病理组织行电镜检查。结果:电镜下观察早期哮喘患者已具备了哮喘病理形态学改变,并且还发现线粒体变性、粗面内质网(RER)扩张及髓磷体的出现和轻度钙过载。意义:即使是早期哮喘患者的病理形态学改变也与 相似文献
88.
目的 探讨癌胚抗原相关细胞黏附分子(CEACAM1)源性多肽KM17对血小板聚集、释放、黏附功能的影响。方法 采用血小板聚集仪观察多肽KM17对凝血酶、胶原、花生四烯酸(AA)、二磷酸腺苷(ADP)等激动剂诱导的血小板聚集的影响;流式细胞术观察多肽KM17对ADP激活血小板后P-选择素释放的影响;显微镜下观察多肽KM17对血小板静态黏附于胶原基质的影响。结果 多肽KM17能显著促进ADP诱导的血小板聚集且呈剂量依赖(P <0.05),而对AA、胶原及凝血酶诱导的血小板聚集差异均无统计学意义(P>0.05);此外,多肽KM17对ADP激活血小板后P-选择素释放及血小板静态黏附于胶原基质的差异也无统计学意义(P>0.05)。结论 多肽KM17可明显促进ADP诱导的血小板聚集,但对ADP活化血小板后P-选择素释放及血小板静态黏附于胶原基质未见明显作用。 相似文献
89.
90.
Priming effect of RANTES on eosinophil oxidative metabolism 总被引:1,自引:0,他引:1
J. Chihara H. Yamada T. Yamamoto D. Kurachi N. Hayashi-Kameda K. Honda H. Kayaba O. Urayama 《Allergy》1998,53(12):1178-1182
Background RANTES has been shown to possess chemotactic activity for eosinophils, which have also been considered to play a role in allergic inflammation through reactive oxygen species. Thus, in this study, we examined the effect of RANTES on radical oxygen products from eosinophils.
Methods Purified eosinophils by CD16-negative selection or an eosinophilic cell line (EoL-1) were incubated with or without RANTES (2.5 x 10−6 ). To the mixture of eosinophils and luminol, calcium ionophore (A23187) or opsonized zymosan (OZ) was added, and radical oxygen products were determined by luminol-dependent chemiluminescence for 600 s.
Results Eosinophil-mediated radical oxygen products of untreated eosinophils produced with A23187 gave a peak value of 14.09 + 2.40 (mean±SE, n = 12) relative light units (RLU) and an integrated value of 3232.20 + 513.09 RLU. However, with treatment with RANTES, a peak value of 18.66 + 2.40 RLU and an integrated value of 5301.05 ±561.02 RLU were obtained. Eosinophil oxidative metabolism-induced A23187 or OZ was apparently augmented by the preincubation with RANTES. In addition, the radical oxygen products of EoL-1 showed similar results.
Conclusions Thus, we concluded that RANTES may play an important role the pathogenesis of allergic inflammation through its involvement in eosinophil activation, as evidenced by oxygen products, as well as in selective eosinophil infiltration as selective eosinophil chemoattractant. 相似文献
Methods Purified eosinophils by CD16-negative selection or an eosinophilic cell line (EoL-1) were incubated with or without RANTES (2.5 x 10
Results Eosinophil-mediated radical oxygen products of untreated eosinophils produced with A23187 gave a peak value of 14.09 + 2.40 (mean±SE, n = 12) relative light units (RLU) and an integrated value of 3232.20 + 513.09 RLU. However, with treatment with RANTES, a peak value of 18.66 + 2.40 RLU and an integrated value of 5301.05 ±561.02 RLU were obtained. Eosinophil oxidative metabolism-induced A23187 or OZ was apparently augmented by the preincubation with RANTES. In addition, the radical oxygen products of EoL-1 showed similar results.
Conclusions Thus, we concluded that RANTES may play an important role the pathogenesis of allergic inflammation through its involvement in eosinophil activation, as evidenced by oxygen products, as well as in selective eosinophil infiltration as selective eosinophil chemoattractant. 相似文献