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101.
Summary The interaction between rauwolscine and angiotensin II was investigated in the isolated mesenteric artery of the rabbit. Rauwolscine, known as an antagonist at 2-adrenoceptors, did not induce contraction itself but interacted with angiotensin to produce a facilitated response of the vascular tissue. In the presence of rauwolscine, the contractile response of the tissue to angiotensin was markedly enhanced. The degree of facilitation appeared to be dependent on the rauwolscine concentration used rather than that of angiotensin. Moreover, rauwolscine induced a concentration-dependent increase in tension (pD2=6.8) in the presence of even subcontractile concentrations of angiotensin (10–10 mol/l). This effect was not attributable to an indirect action involving presynaptic catecholamines, as revealed by the use of tissue strips from animals pretreated with reserpine or after chemical sympathectomy. Furthermore, an interaction via the prostaglandin system was excluded by negative results obtained with indomethacin. The agonistic effect of rauwolscine was significantly attenuated by phentolamine (1/2) but not by prazosin (1) or phenoxybenzamine when applied for only a short time. The 2-antagonist BDF 6143 behaved like rauwolscine whereas the 1-antagonist corynanthine, a stereoisomer of rauwolscine, did not. The results indicate that the rauwolscine effect is mediated by a receptor with 2-characteristics. In general, angiotensin appears to interfere with some process which determines the expression of a drug's intrinsic effect.This study was supported by a grant of the Deutsche Forschungsgemeinschaft  相似文献   
102.
肺癌支气管动脉灌注化疗并发症的防治   总被引:1,自引:0,他引:1  
目的 :探讨肺癌支气管脉灌注化疗 (BAI)并发症产生原因及防治措施。方法 :中晚期肺癌 38例行BAI6 2例次 ,15例次出现并发症。结果 :恶心 ,呕吐 8例次 ,局部皮损 3例次 ,脊髓损伤 2例次。经积极治疗 ,以上并发症均得以控制。结论 :BAI可出现不同并发症 ,应注意预防 ,积极处理  相似文献   
103.
目的观察髂内动脉灌注化疗联合手术治疗膀胱癌的疗效。方法对32例中晚期膀胱癌先行介入治疗,再手术切除。结果32例膀胱癌完全缓解(CR)率为71.9%。结论介入治疗中晚期膀胱的手术提供了良好基础,对一部分原本行扩大切除术甚至全切的患实行单纯部分切除术,从而保留了膀胱生理功能,有助于提高患生活质量,延长生命。  相似文献   
104.
目的 探讨植物有效成分蜕皮甾酮(ecdysteron,EDS)对心肌梗死有益作用,并探讨其机制。方法 采用冠状动脉左前降支结扎致大鼠心肌梗死模型,ip EDS,连续7d。测定血清肌酸磷酸激酶(CPK)、谷草转氨酶(GOT)、乳酸脱氢酶(LDH)活性、心肌梗死面积、冠状动脉血清、毛细血管密度及血管内皮生长因子(VEGF)的表达量。结果 0.5,5,50mg/kgEDS能剂量能依赖地影响大鼠血清CPK、GOT、LDH活性,以5mg/kg剂量的EDS降低心肌酶谱为最佳。5mg/kgEDS能明显减少心肌梗死面积、增加冠状动脉血流量、毛细血管密度和VEGF表达量。结论 EDS能减轻冠状动脉结扎致心肌梗死,机制在于促进VEGF的表达和毛细血管再生及增加冠状动脉血流量。  相似文献   
105.
Introduction and objectivesPreoperative renal artery embolization (PRAE) for large renal masses may be performed prior to nephrectomy in order to simplify the procedure and reduce intraoperative bleeding. The objective of this work is to determine the role of PRAE on intraoperative bleeding and postoperative complications in left renal tumors with tumor thrombus limited to the left renal vein (level 0).Material and methodsRetrospective analysis to evaluate 46 patients who underwent left radical nephrectomy and thrombectomy for the treatment of renal cell carcinoma with level 0 tumor thrombus during the period 1990-2020. PRAE was limited to those cases in which surgical access to the main renal artery was presumed a priori difficult in the preoperative imaging study (n = 9; 19.6%). Intraoperative bleeding was estimated based on the perioperative transfusion rate, and postoperative complications were categorized according to the Clavien-Dindo classification. The Chi-squared test was used for comparisons. A multivariate analysis was performed to identify predictors of transfusion and complications.ResultsThere were no significant differences in the overall complication rate (11.1% vs. 32.4%, P = .19), major complication rate (0% vs.8.1%, P = .51), or transfusion rate (11.1% vs. 19%, P = .49) between both groups (PRAE vs. non-PRAE). In the multivariate analysis, PRAE did not behave as a predictor of complications (OR:0.11, 95%CI 0.01-2.86; P = .18) nor transfusion (OR:0.46, 95%CI 0.02-7.38;P = .58).ConclusionsIn our study on left renal cell carcinomas with level 0 tumor thrombus and difficult access to the main renal artery, PRAE was not associated with increased bleeding or postoperative complications, and it did not behave as an independent predictor of these variables. Therefore, it could be used as a preoperative maneuver to facilitate vascular management in selected cases.  相似文献   
106.
Epistaxis     
《Surgery (Oxford)》2021,39(9):577-590
Epistaxis is a common problem that can affect the whole population. The majority of cases are self-limiting and do not require any medical intervention, but epistaxis can be associated with morbidity and even death in very rare circumstances. If epistaxis does not resolve with first aid measures, or episodes are frequent, patients may require specialist assessment and treatment by ENT, either in the outpatient clinic or via an unscheduled (emergency) admission to the hospital. Here, we provide an overview of the management of epistaxis in the outpatient setting and during an emergency admission in both paediatric and adult patients. We highlight the key considerations in the history and management, covering the common and rare conditions that are associated with epistaxis. This article provides an update from our previous article published in 2018 to include the more recent literature and a useful learning resource for examinations.  相似文献   
107.
108.
IntroductionAneurysm of splenic artery arising from splenomesentric trunk is an extremely rare condition. The aim of this study is to report a new case with literature review.Presentation of caseA 52-year-old housewife presented with mild central abdominal pain for two month duration. Abdomen was soft. Abdominal ultrasound examination showed a focal aneurysmal dilatation in the splenic artery (SA) near the portal vein. Abdominal computed tomographic angiography (CTA) revealed presence of the splenomesentric trunk with fusiform aneurysm (45 × 33 mm) of the proximal part of the SA. In supine position, through upper midline laparotomy incision, exploration of both superior mesenteric artery (SMA) and SA was performed, total excision of the aneurysm was done, the SMA was side-repaired and SA was ligated. The post-operative period was uneventful.DiscussionIt is interesting to note that orthotopic SA aneurysms, most commonly present in the distal third of the artery, followed by the middle third, while in cases of splenomesentric trunk, all reported cases of anomalous SA aneurysms including the current one, showed the aneurysms to be located in the proximal portion or root of the SA.ConclusionSplenomesentric trunk is a rare anatomical anomaly, aneurysm of which is even rarer. It can be managed either by endovascular intervention or open surgery.  相似文献   
109.
110.
臀上动脉深上支髂骨骺移植的解剖学研究   总被引:16,自引:1,他引:16  
目的 :为带血供的髂骨骺移植提供解剖学依据。方法 :在 40侧经动脉灌注红色乳胶的成人臀部标本以及 2侧儿童标本上 ,观测臀上动脉深上支的行程、分支及滋养支 ;选用 5 0块髋骨 ,观察髂骨嵴前外侧部的滋养孔。结果 :儿童臀上动脉深上支的分支、分布与成人相似 ,位于臀中肌深面和臀小肌上缘 (相当臀前线 ) ,循髂骨嵴弓形向前 ,达髂前上嵴 ,沿途分出平均 (4 .2± 1.1)支外径 0 .5~ 1.1mm的髂嵴支 ,分布髂嵴骨膜 ,并发细小分支进入滋养孔。从髂前上棘至结节区 ,在距髂嵴缘下方 2cm范围内 ,平均有(2 2 .4± 6.7)个滋养孔。结论 :以臀上动脉深上支及其分支为蒂 ,在髂嵴前部可切取带骺骨瓣 ,以修复长管骨骨骺缺损。  相似文献   
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