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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.
高强度聚焦超声及其医学应用   总被引:1,自引:0,他引:1  
HIFU技术的研究在国内外已掀起了热潮.到目前为止.HIFU技术已得到广泛的实验和临床支持。本文将对HIFU治疗设备的总体结构做一阐述.并讨论其在医学领域中的应用及发展方向。  相似文献   
4.
凝血酶(thromibin,Ⅱa)是一种生成于损伤处血管内皮细胞多功能蛋白酶,它是参与凝血过程各个环节反应中的关键酶。在发挥止血作用的同时,还可能诱导炎症、增生及修复等反应。最近发现的凝血酶受体(thrombin receptor,TR)分子可能为解释上述现象提供了一个理论框架。同时,TRN端被Ⅱa切下的41个氨基酸片段是否具有特殊功效,值得研究探讨。  相似文献   
5.
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   
6.
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   
7.
8.
Recently neurosurgical operations have been carried out with water irrigation such as endoscopic third ventriculostomy and tumor resections in ventricles. Water irrigation is one of several published methods that promote hemostasis; however, not enough experimental evidence exists on its efficacy. In this study, we investigate whether hydrostatic pressure and persistent irrigation promote hemostasis in neuroendoscopic surgery. We dissected tails of 12–16-week-old C57BL/6 male mice at 5 mm proximal from the tip and checked for bleeding times under dry and wet conditions at pressures of 0 cmH2O, 10 cmH2O, 15 H2O, and 20 cmH2O without persistent irrigation to bleeding point and 10 cmH2O with persistent irrigation. We then examined the dissected edge with hematoxylin–eosin staining and measured the size of vessels. The average bleeding time of each group is as follows: dry: 203.4 sec, wet: 164.4 sec, 5 cmH2O: 138.6 sec, 10 cmH2O: 104.6 sec (P <0.001), 20 cmH2O: 56 sec (P <0.001), and 10 cmH2O with persistent irrigation: 72.8 sec (P <0.01 compared to 10 cmH2O without persistent irrigation). The maximum caliber of mice’s tail artery was 50–60 μm. Hydrostatic pressure and irrigation are important factors contributing to hemostasis.  相似文献   
9.
目的探讨结直肠癌根治术后吻合口出血病人使用急诊内镜检查及止血的安全性和有效性。方法回顾性分析华中科技大学同济医学院附属协和医院2014年1月至2019年11月结直肠癌根治术后吻合口出血行急诊内镜检查以及内镜下治疗的28例病人资料。结果28例病人包括直肠癌术后15例、左半结肠癌术后3例及右半结肠癌术后10例。上述病例均完成急诊内镜检查并接受内镜下止血治疗。仅1例直肠癌术后吻合口出血病人因合并吻合口漏经内镜下止血效果不佳,最终接受外科手术治疗;其余27例吻合口出血病人均经过内镜止血成功。所有病例住院期间无再发出血,内镜诊疗并未导致术后吻合口漏及穿孔。结论结直肠癌根治术后吻合口出血急诊内镜检查及止血的方案,不增加吻合口出血、穿孔及漏等风险。术后急诊内镜下止血是安全有效的治疗手段,能明显提高止血成功率,降低再手术率。在病人出血后8 h内行急诊内镜是非常关键的诊治措施。  相似文献   
10.
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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