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BACKGROUND: The procoagulant effect of anionic phospholipid may play a major role in the development of arterial thrombosis. METHODS AND RESULTS: Annexin V, a calcium-dependent anionic-phospholipid-binding protein, was expressed and isolated from Escherichia coli and its antithrombotic effect examined in a rabbit carotid artery thrombosis model. A partially occlusive thrombus was formed in the left carotid artery by application of electric current to produce an approximately 50% occlusion of the lumen. After the current was discontinued, flow ceased completely within 42+/-12 minutes (n=6) because of continuing platelet/fibrin thrombus formation. When annexin V was given at doses of 2.8 to 16.6 microg x kg(-1) x min(-1) for a period of 180 minutes, starting at the time the current was stopped, there was a dose-dependent inhibition of thrombus formation. At a dose of 5.6 microg x kg(-1) x min(-1), blood flow remained patent throughout the infusion and for an additional 60 minutes after the infusion was stopped. In addition, there was a decrease in thrombus weight (16+/-7.4 versus 2.0+/-1.0 g), (125)I-fibrin deposition (approximately 45% reduction, P<.001), and (111)In-labeled platelet accumulation (approximately 43% reduction, P<.001). Prior mixing of annexin V with phosphatidylserine micelles abolished the antithrombotic effect of annexin V, whereas mixing with phosphatidylcholine micelles had no effect. The antithrombotic effect of annexin V was not associated with bleeding tendency, as judged by the amount of blood absorbed in a gauze pad placed in a surgical incision extending to the muscle tissue and by the standard template bleeding time. CONCLUSIONS: These observations support a potentially important role for anionic phospholipid exposure in platelets in arterial thrombosis, and inhibition of this activity could be a novel target for therapy in coronary thrombosis and stroke and after angioplasty. 相似文献
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Complicated colorectal carcinoma has several symptoms, the most common being bleeding and obstruction. Occasionally it will cause perforation, which carries a worse prognosis. We report a case of perforated adenocarcinoma of the cecum that presented as an abscess of the thigh. We also present a review of the literature on this subject. 相似文献
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Shelton D.J. Cleary J.W. Ginn J.C. Wadsworth S.L. Peale R.E. Kotter D.K. Boreman G.D. 《Electronics letters》2008,44(22):1288-1289
Frequency selective surfaces using Ag dipole antenna elements have been simulated, fabricated and tested to demonstrate improved narrowband transmission compared to the current state of the art in the 1?2 THz. Several designs are presented including variations in dipole packing density, and sensitivity to a cladding layer. The sharpest resonant response was measured to have a bandwidth of 90 GHz at a centre frequency of 1.3 THz, for a Q of 14.5, which is the highest thus far reported for a terahertz narrowband filter. In addition, the sensitivity of the resonance of the structures to material properties may be exploited as a way to measure the permittivity and loss tangent of thin films in the terahertz band. 相似文献
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NJ Carty A Foggitt CR Hamilton GT Royle I Taylor 《Canadian Metallurgical Quarterly》1995,21(6):607-608
Many patients diagnosed with breast cancer will develop metastases and these have diverse presentations. We have reviewed 100 consecutive patients who have died with metastatic breast cancer, to determine the frequency, sites and mode of presentation of recurrent disease. The commonest site of failure was loco-regional (n = 61), this usually presented with a mass, but a minority of patients also complained of pain. Bone metastases developed in 60 patients and produced bone pain, pathological fracture (n = 6) or cord compression (n = 5). Pulmonary metastases producing shortness of breath were diagnosed in 34 patients and were asymptomatic in a further 10. Intra-abdominal metastases were found at some time in 23 patients, most commonly in the liver (n = 20) and the majority complained of epigastric pain (n = 17). Brain metastases occurred in 23 patients and produced a wide range of symptoms including those of a space-occupying lesion (n = 10), cranial nerve palsy (n = 7), diabetes insipidus (n = 3), focal limb weakness (n = 2) and meningitis (n = 1). Three patients had choroid metastases producing reduced visual acuity. Recurrent breast carcinoma can present in a variety of ways, therefore any new symptom or sign should be considered to represent recurrence until proved otherwise. 相似文献
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G. R. Shelton 《Journal of the American Ceramic Society》1929,12(2):79-142
The relationship among the minerals pyrophyllite, kaolinite, and steatite together with a statement of the properties of pyrophyllite are given. The North Carolina deposits of pyrophyllite are briefly described. A preliminary report is made on tests now being conducted to determine the possible use of pyrophyllite as a constituent in whiteware bodies. 相似文献
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