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61.
Female rats develop haemolytic anaemia and disseminated thrombosis and infarction in multiple organs, including bone, when exposed to 2-butoxyethanol (BE). There is growing evidence that vascular occlusion of the subchondral bone may play a part in some cases of osteoarthritis. The subchondral bone is the main weight bearer as well as the source of the blood supply to the mandibular articular cartilage. Vascular occlusion is thought to be linked to sclerosis of the subchondral bone associated with disintegration of the articular cartilage. The aim of this study was to find out whether this model of haemolysis and disseminated thrombosis supports the vascular hypothesis of osteoarthritis. Six female rats were given BE orally for 4 consecutive days and the two control rats were given tap water alone. The rats were killed 26 days after the final dose. The mandibular condyles showed histological and radiological features consistent with osteoarthritis in three of the four experimental rats and in neither of the control rats. These results may support the need to explore the vascular mechanism of osteoarthritis further.  相似文献   
62.
目的 探讨小分子多肽血栓显像剂99Tcm-邻苯二甲酸二甲酯(DMP) 444在PE和下肢深静脉血栓(DVT)动物模型中的显像效果.方法 选5条杂种犬,制备左下肺动脉血栓和右股静脉血栓动物模型.注射显像剂后即刻(30 s)、2、3、4、5、10、15、30、60、90和120 min分别取静脉血1ml,测质量及放射性计数.以注射后即刻的血液放射性计数为100%,计算各时间点的99Tcm-DMP444血液清除率.注射后15、30、60、90和120 min,分别进行胸部及双后肢平面显像.应用ROI方法,分别计算肺血栓/肺本底(P/L)、股静脉血栓/对侧股静脉血(D/B)和股静脉血栓/肌肉本底(D/M)的放射性比值.显像结束后,取出血栓分别测定肺动脉血栓和股静脉血栓摄取99Tcm-DMP444的%ID/g.不同时间点均数之间的差异采用单向重复测量方差分析.结果 99Tcm-DMP444注射后120 min的血液清除率为(65.4±3.9)%.左下肺动脉及右股静脉血栓部位放射性摄取随时间逐步增强,注射后15至120 min,P/L,D/B和D/M比值分别从2.41±0.28、1.67±0.33、2.20±0.14增加至3.96±0.64、2.56±0.57、3.90±0.95,差异均有统计学意义(F=14.57、7.68和9.37,P均<0.05).PE和后肢DVT的%ID/g分别为0.085±0.023和0.054±0.018.结论 99Tcm-DMP444能无创性地早期检测急性PE和下肢DVT,是较为理想的小分子多肽血栓显像剂.  相似文献   
63.
The benefit of antiplatelet therapy remains unclear, although it does appear that aspirin monotherapy started within 48 hours of stroke onset may result in a modest clinical improvement. Glicoprotein (GP) IIb/IIIa antagonists are currently considered the most powerful specific inhibitors of platelet activation in acute thrombosis. Glicoprotein IIb/IIIa inhibitor therapy could merit a prominent role also in the initial management of patients with acute ischemic stroke. Abciximab may be promising in this setting and should be evaluated in further clinical trials.  相似文献   
64.
甘慧珍  董宏  李斌  顾红菲 《中医临床研究》2012,4(15):83+85-83,85
脑梗塞是常见缺血性脑血管疾病,发病率逐年增高,其致死率、致残率高的特性严重危害着患者身体健康及生活质量。近年已成为医学和社会重点关注的课题,如何进一步提高对脑梗塞的治疗效果,降低致残率,提高患者的生活质量同时做好二级预防,降低复发率,是我们目前需要解决的一个重要问题。各种围绕治疗卒中的药物有很多,具体疗效各有不同,我们对脑血栓片治疗脑梗塞的疗效进行了观察。  相似文献   
65.
We investigated the effects of viral infection on Tissue Factor (TF) expression and activity in mice within the myocardium to understand increased thrombosis during myocarditis. Mice were infected with coxsackie virus B3 (CVB3) and the hearts were collected at day 4, 8 and 28 post infection (p.i.). Myocardial TF expression and cellular activity as well as plasma activity were analyzed from CVB3 infected mice by Western blot, chromogenic Factor Xa generation assay, in situ staining for active TF and immunohistochemistry. In addition to TF expression, hemodynamic parameters were measured during the time course of infection. Furthermore, we analyzed myocardial tissues from patients with suspected inflammatory cardiomyopathy. TF protein expression was maximally 5-fold elevated 8 days p.i. in mice and remained increased on day 28 p.i. (P < 0.001 vs. non-infected controls). Alterations in TF expression were associated with fibrin deposits within the myocardium. The TF pathway inhibitor protein expression in the myocardium was not altered during myocarditis. Active cellular TF co-localized with CD3 positive cells and VCAM-1 positive endothelial cells in the myocardium. The TF expression was positively correlated with the amount of infiltrating CD3 and Mac3 positive cells (Spearman-Rho ρ = 0.749 P < 0.0001 for CD3+ and ρ = 0.775 P < 0.0001 for Mac3+; N = 35). Increased myocardial TF expression was associated with a 2-fold elevated plasma activity (P < 0.05 vs. non-infected controls). In the human hearts, the TF expression correlated postively with an endothelial cell activation marker (ρ = 0.523 P < 0.0001 for CD62E; N = 54). Viral myocarditis is a hypercoagulative state which is associated with increased myocardial TF expression and activity. Upregulation of TF contributes to a systemic activation of the coagulation cascade.  相似文献   
66.
Summary To demonstrate the wide variety of clinical syndromes associated with the lupus anticoagulant (LAC), we report the case histories of three young females with arterial thrombosis in whom LAC was demonstrated. Two patients had a diagnosis of systemic lupus erythematosus and mixed connective tissue disease respectively; the other patient had no signs of underlying auto-immune disease. Arterial thrombotic events in young females should arouse suspicion of the presence of LAC although its pathophysiological significance is not established.  相似文献   
67.
BACKGROUND: Little is known about the morphological and functional evolution of ventricular abnormalities in Loeffler endocarditis. METHODS AND RESULTS: We describe 5 patients, including 3 with long-term echocardiographic follow-up, in whom apical obliteration due to fibro-thrombotic thickening of the endocardium showed favorable patterns of evolution. In one patient there was almost complete resolution of the obliterative process with consequently increased effective ventricular volume. In two patients formation of a flow-passage in the fibrocalcific apical 'floor' between the main medioventricular cavity and the apical chamber, leading to a 'double-chambered' left ventricle was observed. CONCLUSIONS: Medical therapy and appropriate anticoagulation, can induce favorable long-term ventricular remodeling in Loeffler endocarditis.  相似文献   
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70.
范星  林利  任星峰  彭隽  兰天飚 《中国药师》2015,(8):1328-1330
摘 要 目的: 研究肝素联合低分子肝素对预防动静脉内瘘(AVF)术后早期血栓形成的影响。方法: 采用前瞻性研究方法,将299例行AVF术的患者随机分为两组,对照组患者术后给予低分子肝素5 000 IU皮下注射qd×7 d;观察组术中在游离动脉端与静脉端分别推注1 500 u肝素钠,术后给予低分子肝素5 000 IU皮下注射qd×7 d。观察两组患者术后1周和4周AVF血栓形成率及药品不良反应(ADR)发生情况。结果: 术后1周,对照组和观察组的AVF血栓形成率分别为3.4%和0;术后4周分别为4.8%和0.67%,观察组均明显低于对照组(P<0.05)。两组ADR发生率差异无统计学意义(P>0.05),未发生严重不良反应。结论: 肝素联合低分子肝素可降低AVF术后早期血栓形成率,提高手术成功率,安全性较好。  相似文献   
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