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51.
52.
We investigated the effects of statin treatment on platelet-derived microparticles (PMPs) and thrombin generation in atherothrombotic disease. Nineteen patients with peripheral arterial occlusive disease were randomised to eight weeks of treatment with atorvastatin or placebo in a cross-over fashion. Expression of GPIIIa (CD61), P-selectin (CD62P), tissue factor (TF, CD142) and phosphatidylserine (PS; annexin-V or lactadherin binding) was assessed on PMPs. Thrombin generation in vivo was assessed by measurement of prothrombin fragment 1+2 in plasma (F1+2) and ex vivo by using the calibrated automated thrombogram (CAT). During atorvastatin treatment, expression of TF, P-selectin and GPIIIa was significantly reduced vs. placebo (p<0.001 for all). No effect on annexin-V or lactadherin binding was seen. Thrombin generation was significantly reduced during atorvastatin as assessed by both the CAT assay (p<0.001) and by measurements of F1+2 (p<0.01). Subsequent in vitro experiments showed that when TF on microparticles (MPs) was blocked by antibodies, the initiation of thrombin generation was slightly but significantly delayed. Blocking PS on MPs using annexin-V or lactadherin resulted in almost complete inhibition of thrombin generation. In conclusion, atorvastatin reduces thrombin generation and expression of TF, GPIIIa and P-selectin on PMPs in patients with peripheral vascular disease. Microparticle-bound TF slightly enhances initiation of thrombin generation whereas negatively charged surfaces provided by MPs or lipoproteins could reinforce thrombin generation. Statins may inhibit initiation of thrombin generation partly through a microparticle dependent mechanism but the main effect is probably through reduction of lipoprotein levels.  相似文献   
53.
This is a narrative review of various treatment modalities for advanced hepatocellular carcinoma (HCC), with a focus on recent updates in radiological treatments, as well as novel treatment concepts related to immune checkpoint inhibitors and combination therapies with locoregional treatments. Interventional radiologists have made efforts toward developing alternative and/or combination treatments for first-line systemic treatment of patients with advanced HCC. Locoregional treatments with or without systemic therapy may be considered in the selected patients. Various treatment modalities for advanced HCC are emerging, and several randomized controlled trials, including those of combination treatments with immunotherapy, are ongoing.  相似文献   
54.
SYNOPSIS
The prophylactic anti-migraine effect of atenolol was compared to placebo in a multicentre study on 63 patients with classical and/or common migraine. The study design was double-blind cross-over and patients were given atenolol 100 mg o.d. or matching placebo during a study treatment period of 24 weeks. The effect of atenolol was significantly better than that of placebo: integrated headache values were reduced in 70% of the patients (p = 0.004) and the proportion of days with headache was reduced in 59% of the patients (p = 0.010). Few side effects were reported with both atenolol and placebo. This study shows atenolol to be safe and effective in the prophylactic treatment of migraine.  相似文献   
55.
目的 探讨和评估选择性靶动脉栓塞骶骨肿瘤后对外科切除肿瘤的价值和方法。方法 运用Seldinger技术,对9例骶骨肿瘤患者进行肿瘤供血动脉及肿瘤内血管全部彻底栓塞,栓塞材料应用明胶海绵,栓塞后1周内行手术切除术。结果 彻底的术前栓塞手术中失血量明显减少,9例骶骨肿瘤均得到彻底切除,平均失血量为1090ml。术后平均随访15个月,未见肿瘤局部复发。结论 骶骨肿瘤切除术前选择性靶动脉栓塞可有效减少术中出血,有利于肿瘤的彻底切除,为顺利切除骶骨肿瘤提供了有价值的方法。  相似文献   
56.
Transmission estimation is the most challenging part for single image haze removal and very sensitive to environment noise. However, most existing single image dehazing algorithms are far from satisfactory in terms of restoring an image’s details and noise removal. To address this issue, an improved haze imaging model with transmission refinement based on dark channel prior is constructed to preserve the edge details and enhance visibility. Then, a fast single image dehazing algorithm called TSGA algorithm is proposed for complex real-world images. A refined transmission map obtained by TGVSH regularity scheme provides more edges and finer details and is less susceptible to noise. Guided filter and adaptive histogram equalization greatly enhance the visibility and color contrast of the scenes and significantly improve the drawback of halo artifacts. A large quantity of comparative experiment results demonstrate that the proposed algorithm simultaneously removes the serious effect of haze and noise, effectively makes the restored images look more natural, and has a lower time complexity. All these make it a good candidate for image segmentation, object recognition, and target tracking in complex real-world weather conditions.  相似文献   
57.
Nasal osteotomies are the most important cause of periorbital edema and ecchymosis. Injection of lidocaine and adrenaline is recommended to reduce bleeding. Whilst the lidocaine and adrenaline combination (LAC) is claimed to reduce postoperative ecchymosis and edema, this effect remains to be proven conclusively. This study, on 48 patients, was designed to investigate the effects of LAC injection on postoperative edema/ecchymosis in rhinoplasty. LAC was applied at a random side prior to the lateral osteotomy. The opposite side was used as a control. The relationship between edema/ecchymosis and the degree of LAC on the injected and uninjected sides was evaluated on the first, third and seventh day postoperatively. The relationships between edema and ecchymosis with operation time and intraoperative systolic blood pressure were also evaluated. Bleeding was reduced on the side treated with LAC (p = 0.050). The degrees of edema/ecchymosis increased with increases in the duration of operation and the systolic blood pressure on the first postoperative day for the LAC-applied side (p < 0.05). This correlation was not observed on the opposite side (p > 0.05). Application of LAC reduces bleeding during rhinoplasty and pain control postoperatively but reduced edema and ecchymosis should not be expected following LAC application.  相似文献   
58.
腰椎椎管狭窄症(lumbar spinal stenosis,LSS)是临床常见的脊柱外科疾病之一,老年人多见。其临床特点为神经源性跛行或根性痛,它是腰椎椎管、神经根管或椎间孔狭窄所致马尾或/和神经根的压迫综合征。治疗LSS的腰椎后路植骨融合术可分为腰椎后外侧植骨融合术(posterolateral lumbar  相似文献   
59.
60.
Bone morphogenetic proteins (BMPs) and transforming growth factor‐beta (TGF‐β) contribute to the growth of some skeletal metastases through autocrine stimulation. Secreted phosphoprotein 24 kDa (spp24) has been shown to bind to both BMP‐2 and TGF‐β and to markedly inhibit the osteogenic properties of rhBMP‐2. We hypothesized that the addition of spp24 would sequester autocrine growth factors (especially BMP‐2) and reduce tumor growth in a system (A549 human non‐small cell lung cancer cell line) where autocrine stimulation by BMP‐2 is known to be important. A549 cells were injected into two sites (subcutaneous and intraosseus) in SCID mice with and without the co‐injection of BMP‐2 and spp24. Tumor growth after 8 weeks was assessed through gross examination, radiological imaging, and histological analysis. Spp24 attenuated the tumor growth enhancing effects of rhBMP‐2 and reduced the tumor growth when added to tumor cells that were not treated with BMP‐2. We conclude that spp24 can reduce A549 cell tumor growth in both soft tissue and intraosseus environments. We hypothesize that the mechanism for this inhibition is interruption of autocrine stimulation through the sequestration of BMP‐2. Spp24 can be developed into a therapeutic agent that can be employed in clinical situations where the inhibitions of BMPs and related proteins is advantageous. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1712–1718, 2011  相似文献   
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