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1.
Background: Although bleeding is an unavoidable complication of endoscopic submucosal dissection (ESD), endoscopic hemostasis using an insulation‐tipped electrosurgical knife (IT) knife is impossible because an insulator is mounted at the tip of the knife. We have developed a new type of hood which could perform both coagulation and irrigation simultaneously. Methods: Our new device was fabricated by drilling a side hole in the cap portion of a conventional transparent hood followed by attaching a machined papillotomy knife to the exterior surface of the hole. Results: Our new hood was useful for hemorrhage during ESD using IT knife. Conclusions: With this method, endoscopic hemostasis using IT knife is easy, as hemostatic procedure can be performed under irrigation and coagulation using conventional endoscopy.  相似文献   
2.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。  相似文献   
3.
Background : Nonsteroidal anti–inflammatory drugs (NSAIDs) inhibit prostaglandin synthesis which may result in impaired platelet function. Because NSAIDs have different abilities to inhibit cyclo–oxygenases we compared the effect of intravenous ketoprofen, ketorolac and diclofenac on platelet function in volunteers. Methods : Ten healthy male volunteers were given ketoprofen 1.4 mg kg-1, ketorolac 0.4 mg kg-1 and diclofenac 1.1 mg kg-1 in saline i.v. on three different occasions, at more than one–week intervals, in a randomized double–blind crossover study. Platelet function was evaluated before (sample 0), 2 (sample 2) and 24 h (sample 3) after the beginning of the infusion. Results : Two of the volunteers had no secondary platelet aggregation in their aggregation curves before the experiment (sample 0, studied three times) and their results were excluded from the final analysis. Diclofenac inhibited adrenaline (0.9 μg–ml-1) induced platelet aggregation less (median maximal aggregation 22.5%) than ketoprofen (18.3%) and ketorolac (15.7%) (P<0.05) in sample 2. In the ketorolac group in sample 3 an impairment of adrenaline (0.9 ng ml-1) induced platelet aggregation was still seen (26.7%) (P<0.05) but not in the other groups. Diclofenac did not affect adenosine diphosphate (ADP) induced platelet aggregation. However, ketorolac caused an impairment in ADP (3 μM and 6 μM) induced platelet aggregation and ketoprofen in ADP (6 μM) induced platelet aggregation in sample 2. Bleeding time was prolonged (P<0.05) after ketoprofen and ketorolac (sample 2) but not after diclofenac. Platelet retention on glass beads was unaffected by the tested drugs. Conclusion : Ketoprofen, ketorolac and diclofenac caused a reversible platelet dysfunction. Diclofenac had the mildest effect, while platelet dysfunction was still seen 24 h after the beginning of ketorolac.  相似文献   
4.
A prospective study was conducted to evaluate a new compact portable coagulation monitor (Ciba–Corning Biotrack 512 Monitor), which enables the clinician to perform instantaneous activated partial thromboplastin time (APTT) and prothrombin time (PT). 126 patients scheduled for heparinized and nonheparinized vascular surgery, and gynaecological surgery, were included. A drop of capillary or venous whole blood was applied in disposable cartridges to successively perform APTT and PT, and the results of the tests were compared with conventional laboratory methods, performed in two different laboratories (Lab. A and B). Comparisons between Lab. A. and Lab. B. enables determination of the bias, precision, and percent of outliers (patients whose values differed more than 20%) in conventional methods. The reference value was defined as the mean of Lab. A. and Lab. B. values. For PT, there were no statistical differences between the capillary and venous samples performed with the portable monitor, and the reference value, for the bias, the precision and the proportion of outliers. For APTT, there were no statistical differences between the capillary and venous samples performed with the portable monitor, and the reference value, for the bias and the precision. The percent of outliers, however, was significantly greater with the venous sample of the compact monitor than with the reference (48 versus 22%), and even if it did not reach the statistical significance ( P = 0.07) it was also higher with the capillary sample performed with the Ciba Monitor than with the reference (33%). In conclusion the assessment of blood coagulation using this new compact monitor could be of major interest during the intraoperative period when immediate results are mandatory, even if PT is more accurate than APTT with this new method.  相似文献   
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6.
Platelet activation and thrombus formation have been implicated to be detrimental for intraportal pancreatic islet transplants. The platelet-specific collagen receptor glycoprotein VI (GPVI) plays a key role in thrombosis through cellular activation and the subsequent release of secondary mediators. In aggregometry and in a microfluidic dynamic assay system modeling flow in the portal vein, pancreatic islets promoted platelet aggregation and triggered thrombus formation, respectively. While platelet GPVI deficiency did not affect the initiation of these events, it was found to destabilize platelet aggregates and thrombi in this process. Interestingly, while no major difference was detected in early thrombus formation after intraportal islet transplantation, genetic GPVI deficiency or acute anti-GPVI treatment led to an inferior graft survival and function in both syngeneic mouse islet transplantation and xenogeneic human islet transplantation models. These results demonstrate that platelet GPVI signaling is indispensable in stable thrombus formation induced by pancreatic islets. GPVI deficiency resulted in thrombus destabilization and inferior islet engraftment indicating that thrombus formation is necessary for a successful intraportal islet transplantation in which platelets are active modulators.  相似文献   
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目的观察内镜下止血治疗烧伤后应激性溃疡大出血的临床效果。方法对15例烧伤后应激性溃疡大出血患者应用电子胃镜行病灶局部注射硬化剂止血,并同时给予综合治疗。结果所有病例均在内镜下止血成功。平均随访一年,无一例复发,未进行外科手术。结论内镜下止血治疗烧伤后应激性溃疡疗效确切,使病人避免了外科手术治疗,复发率低,值得开展。  相似文献   
9.
茜草饮片炒炭前后止血机制的比较   总被引:4,自引:1,他引:4  
目的:探讨茜草及茜草炭止血作用机制。方法:比较茜草和茜草炭对小鼠凝血时间、出血时间、血小板计数、毛细血管通透性、肝素和华发林所致病理性出血模型以及大鼠凝血酶时间(TT)、凝血酶原时间(PT)、部分凝血活酶时间(APTT)的影响。结果:茜草和茜草炭均能抑制小鼠腹腔毛细血管通透性,均能明显缩短大鼠TT、PT、APTT,但茜草炭作用强于茜草。茜草大小剂量和茜草炭饮片大剂量能提高小鼠血小板计数,明显对抗肝素及华发林的出血作用,茜草作用强于茜草炭。结论:茜草主要通过提高血小板计数,对抗肝素及华发林的出血来发挥止血作用;茜草炭主要通过抑制毛细血管通透性,缩短TT、PT、APTT来发挥止血作用;茜草和茜草炭的止血作用机制不同。  相似文献   
10.
目的观察消痔洗剂的抗炎、镇痛、止血作用。方法采用二甲苯致小鼠耳肿胀法、醋酸致小鼠扭体反应法、小鼠尾尖止血法,分别观察消痔洗剂的抗炎、镇痛、止血作用。结果消痔洗剂可显著降低二甲苯致小鼠耳肿胀,其最高的肿胀抑制率超过40%;显著降低小鼠的扭体反应数,其中以8.4 g生药/kg剂量组最为显著,该剂量组各时间段的镇痛百分率均在40%以上,最高为50.6%;显著缩短小鼠尾尖的出血时间,以消痔洗剂的1.68,3.36 g生药/mL剂量组作用最为明显。结论消痔洗剂具有显著的抗炎、镇痛、止血作用。  相似文献   
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