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61.
Background: We evaluated the endoscopic microvascular architecture of the gastric mucosa in portal hypertension patients using the prototype of narrow band imaging (NBI). Material and Methods: The study included 103 Helicobacter pylori‐negative patients with chronic liver disease (22 without portal hypertension (group 1), 81 with portal hypertension (group 2)). Results: (i) Abnormality of collecting venules, reddening mucosa, red spots, a mosaic‐like pattern, and gastric antral vascular ectasia (GAVE) were observed on the gastric mucosa, and an obscure change in collecting venules (73% vs 14%; P < 0.001), reddening mucosa (49% vs 5%; P < 0.001), red spots (36% vs 5%; P < 0.01) and a mosaic‐like pattern (40% vs 5%; P < 0.01) were more frequently observed in group 2 than in group 1. (ii) On magnifying endoscopy with NBI, the mucosa with an obscure change in collecting venules was demonstrated as dilation of the capillaries surrounding the gastric pits in various degrees, and reddening mucosa was observed as extended and swollen gastric pits and various degrees of dilated and convoluted capillaries surrounding the gastric pits. Red spots were demonstrated as extended and swollen gastric pits, dilated and convoluted capillaries surrounding the gastric pits, and intramucosal hemorrhage around these capillaries. GAVE was recognized as partial and marked dilatation of the capillaries surrounding the gastric pits. Conclusion: Abnormality of collecting venules, swelling of gastric pits, dilatation of capillaries surrounding the gastric pits, intramucosal hemorrhage around capillaries, and partial and marked dilatation of the capillaries were observed on the gastric mucosa in portal hypertension patients.  相似文献   
62.
目的 利用包裹绿脓杆菌外毒素单元Ⅲ的VEGF(血管内皮生长因子)-脂质体于体外靶向杀伤肿瘤血管内皮细胞。方法 通过结合实验。验证VEGF连接脂质体对肿瘤血管内皮细胞具有特异结合能力。利用体外细胞毒实验(MTT)方法,检测外毒素单元Ⅲ及靶向脂质体包裹的单元Ⅲ对肿瘤血管内皮细胞的杀伤作用。结果 连有VEGF的脂质体可与表达血管内皮生长因子受体(VEGFR)的肿瘤血管内皮细胞特异性结合。结合率可达非特异性脂质体的2倍。在去除外毒素单元Ⅰ和Ⅱ后,单元Ⅲ的细胞毒作用消失。但包裹单元Ⅲ的VEGF-脂质体可特异性杀伤肿瘤血管内皮细胞。结论 VEGF-脂质体可特异性地识别肿瘤血管内皮细胞。并作为良好载体将绿脓杆菌外毒素单元Ⅲ带入细胞,实现其杀伤作用,可望成为一种有效的抗肿瘤物质。  相似文献   
63.
导航辅助脊柱胸腰段椎弓根钉植入的临床应用   总被引:1,自引:0,他引:1  
目的探讨临床运用计算机影像导航技术引导脊柱胸腰段椎弓根钉植入的准确性。方法2003年5月-2007年5月,29例患者接受116枚计算机影像导航技术引导脊柱胸腰段椎弓根钉植入手术治疗,T10-T1250枚胸椎弓根钉,L1-L3 66枚腰椎弓根钉。术中记录椎弓根钉植入所需时间及C-臂透视工作次数,椎弓根钉植入完成后,即行C-臂正侧位摄片并与导航路径进行比较测量。术后CT进行椎弓根层面扫描,根据椎弓根钉与椎弓根皮质问关系分为四级:A=在椎弓根内;B=突破皮质,〈2mm;C=突破皮质,2-4mm;C=突破皮质,〉4mm。结果术后CT椎弓根位置扫描显示:A级101枚(87.07%);B级10枚(8.62%);C级2枚(1.72%);D级3枚(2.59%)。1枚椎弓根钉植入平均所需时间:2.73±0.64min(1.15~4.02min)。下胸椎9枚(7.75%)胸椎弓根钉突破皮质,上腰椎6枚(5.17%)腰椎弓根钉突破皮质,且临床观察未发现与椎弓根钉突破皮质相关的神经血管等并发症。植入的椎弓根钉C-臂正侧位摄片与导航路径吻合比较,进钉点均差2.6mm(最大3.1mm),角度均差3.3°(最大5.4°)。结论计算机影像导航辅助脊柱胸腰段椎弓根钉植入,提供二维、多平面实时显示,保证了脊柱胸腰段椎弓根钉植入的准确性及安全性,明显减少放射线的暴露强度。  相似文献   
64.
目的:探讨外周血循环内皮细胞(CEC)和糖尿病肾病(DN)的相关性,以及银杏达莫注射液在DN防治中的可能作用。方法:检测65例2型糖尿病患者24h尿白蛋白排泄率(UAER)及CEC数,分析两者的相关性。将UAER为30~300mg·d-1的45例患者随机分为两组,常规治疗组22例,进行常规降血糖、控制血压等治疗;银杏达莫治疗组23例,在常规治疗基础上静脉滴注银杏达莫注射液2周。比较两组治疗前后血糖、血压、UAER及CEC水平的变化。结果:单纯糖尿病(SDM)组和早期糖尿病肾病(EDN)组的外周血CEC水平比对照组(NC)显著性升高,并呈逐渐增高的趋势(P<0.01)。UAER与收缩压(SBP)、外周血CEC水平呈正相关(P<0.01)。EDN组中,银杏达莫治疗后UAER及CEC明显降低(P<0.01);而常规治疗组无明显变化。线性多元逐步回归分析表明,银杏达莫治疗后UAER的改变与CEC数的变化成正相关(P<0.01)。结论:血管内皮细胞(VEC)损伤在DN发生发展中起重要作用,银杏达莫对VEC的保护作用可能是其延缓DN发展的重要机制。  相似文献   
65.
CD-Horizon器械治疗特发性脊柱侧凸的临床研究   总被引:4,自引:1,他引:3  
[目的]探讨特发牲脊柱侧凸治疗方法,总结应用CD-Horizon(CD-H)钉-棒系统与钉-钩-棒系统的治疗效果。[方法]自2000年1月~2004年1月,采用CD-H器械治疗85例特发性脊柱侧凸患者,其中钉-棒系统51例(A组),钉-钩-棒系统34例(B组),比较术前、术后与随访2年冠状面与矢状面的角度及旋转度。[结果]85例患者平均随访3年半,术后及随访2年时冠状面及矢状面矫正率A组明显优于B组(P<0.05)。术后2年2组冠状面矫正度的丢失有明显的差异。2组患者旋转矫正Ⅰ~Ⅱ度。术前、术后及术后2年,2组Cobb s角自身得分显示术后明显低于术前(P<0.05),与术后2年随访得分相比无差异(P>0.05)。[结论]CD-Horizon器械是治疗特发性脊柱侧凸比较有效的方法,钉-棒系统较钉-钩-棒系统相比效果更佳。  相似文献   
66.
67.
王宝奎  邓树才  窦如明  甄刚 《中国矫形外科杂志》2007,15(9):660-662,671,I0004
[目的]探讨椎弓根螺钉系统联合椎间植骨融合器治疗峡部不连性腰椎滑脱症的远期疗效。[方法]自1996年10月~2002年10月本组收治峡部不连性腰椎滑脱症105例,随访资料齐全者86例。所有患者均行椎弓根螺钉系统复位滑脱,椎间植骨融合器行椎间融合固定。62例患者中1枚融合器从后斜向前呈45°植入,24例为2枚融合器从后向前垂直植入。随访测定固定节段的椎体间有无移位、滑脱有无复发,比较术前、术后2周及随访时固定椎间隙高度与近端第2椎间隙高度比值的变化。[结果]随访2~8年,平均35个月。根据NaKai评分标准,本组优56例,良13例,可17例,优良率为80.23%。Ⅰ度腰椎滑脱19例术后全部解剖复位;Ⅱ度腰椎滑脱51例中5例遗留Ⅰ度滑脱;Ⅲ度腰椎滑脱16例中4例留有Ⅰ度滑脱。末次随访时使用1枚融合器或2枚融合器所固定的椎间隙高度与近端第2椎间隙高度的比值与术后2周时的比值相比有所减低,滑脱无复发。[结论]椎弓根螺钉加椎间植骨融合器治疗腰椎滑脱症手术疗效满意,显著提高融合率,预防神经根管狭窄、神经卡压的发生,减少术后断钉和滑脱复发等问题。  相似文献   
68.
Background: Retinal pigment epithelium (RPE)lesions are predictive congenital phenotypic markersfor familial adenomatous polyposis (FAP). Thisprospective screening study aims at assessing theincidence and significance of these lesions in FAPpatients and their family members.Methods: Sixty-two members from three familiesincluding five patients with the diagnosis of FAP havebeen ophthalmologically surveyed. All RPE lesions weredocumented with fundus photography and fluoresceinangiography was performed in 13 subjects.Sigmoidoscopy and/or radiological examination wereperformed annually in 9 family members with typicalRPE lesions during 4 years to allow early diagnosis ofFAP.Results: Typical RPE lesions were present infive FAP patients and 15 family members.Telangiectatic dilatations in the retinal peripherywith small dot-like hemorrhages were detected in 6subjects from 3 families These lesions wereparticularly evident on fluorescein angiography.Annual colon analysis showed polyps in 3 out of 9subjects who were positive for RPE lesions.Conclusion: RPE lesions are valuable as aclinical marker in predicting FAP. The co-existingperipheral vascular alterations which have not beenreported before, are probably related to FAP.  相似文献   
69.
Antiarrhythmic and Placental Vessels. Introduction : Antiarrhythmic medications are commonly used during pregnancy for treatment of maternal or fetal arrhythmias, but little is known about their effect on human placental vascular tone and, consequently, placental blood flow. The objective of this study was to evaluate the tone responses caused by antiarrhythmic medications in human placental vessels from normal term pregnancies in vitro.
Methods and Results : Isolated human placental arteries and veins from uncomplicated term pregnancies incubated in Krebs'-bicarbonate under 5% oxygen/5% carbon dioxide/balance nitrogen (PO2 35 to 38 torr) were exposed to cumulative doses of quinidine, procainamide, lidocaine, flecainide, propranolol, amiodarone, verapamil, digoxin, and adenosine after submaximal contraction with 5-hydroxytryptamine. The study was conducted both in the presence and absence of endothelium. The addition of the tested medications caused a significant, dose-dependent relaxation of human placental arteries and veins except for adenosine, which induced a sustained, dose-dependent contraction of human placental vessels regardless of the presence or absence of tone. Removal of the endothelium did not alter these responses.
Conclusions : Based on these results, the medications tested should have no decremental effect on placental blood flow, with the possible exception of adenosine, which causes significant. dosedependent contraction of human placental vessels in vitro. Should similar contraction be present in vivo, it may have an adverse effect on the fetus when administering adenosine to pregnant women at term or during labor.  相似文献   
70.
The goal of the present study is to develop a technique for laparoscopic aortobifemoral bypass.Piglets weighing between 60 and 78 kg were anesthetized with halothane. The lateral retroperitoneal approach was preferred to the more familiar anterior transperitoneal approach and was successfully completed in 19 piglets. The piglets were placed in the right lateral decubitus position. The first port (2 cm) was inserted halfway between the tip of the 12th rib and the iliac crest. Four other trocars were placed in the retroperitoneum after balloon inflation had allowed creation of a space which permitted visualization of the aorta from the left renal artery down to the aorto-iliac junction. After evacuation of the retropneumoperitoneum, the cavity was maintained using an abdominal lift device and a retractor.Using this approach, we performed four aortobifemoral bypasses (end-to-end aortic anastomosis) after conventional intravenous heparinization (100 IU/kg) in less than 4 h. Blood loss did not exceed 250 ml and the hematocrit remained stable. Postmortem evaluation of the grafts revealed they were positioned as in a conventional bypass, their limbs having followed in the created retroperitoneal tunnels along the path of the native arteries. No mortality occurred before sacrifice of the animals. We believe that this first performed series of totally retroperitoneal laparoscopic aortobifemoral bypasses in the porcine model is useful in preparation for human application due to the anatomical similarities in the periaortic region.  相似文献   
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