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81.
目的 利用可吸收缝线缝扎部分胆总管建立兔损伤性胆管狭窄动物模型.方法 24只新西兰兔按完全随机方法分为3组:正常对照组、假手术对照组和手术组.手术组用6-0可吸收缝线缝扎1/2胆总管,手术当天和术后15、30 d检验血清肝功能指标,取狭窄段胆总管行HE染色、Masson三色染色检测胶原纤维和肌纤维的表达,免疫组化DAB法检测狭窄段胆管组织Ⅰ、Ⅲ型胶原的表达.结果 手术组动物直接胆红素、间接胆红素、丙氨酸氨基转移酶和天门冬氨酸氨基转移酶在30 d均高于术前(P<0.01).术中观察胆总管损伤处明显狭窄,手术组病理切片中,胶原纤维大量增生形成瘢痕组织,Ⅰ、Ⅲ型胶原随着时间推移表达强度逐渐增强.结论 可吸收缝线缝扎法可有效建立兔胆总管良性狭窄模型.  相似文献   
82.
目的:探讨经尿道前列腺电切术(transurethral resection of the prostate,TURP)术后尿道狭窄的形成原因及防治措施。方法:回顾性分析21例TURP术后尿道狭窄患者的临床资料,针对不同情况分别采取尿道扩张、尿道内切开、残留前列腺组织切除或瘢痕切除等治疗措施。结果:随访3~8个月,行尿道扩张18例(86%)中,有16例排尿通畅,有2例仍进行巩固性尿道扩张,1次/月;3例(14%)手术患者中,有2例排尿满意,1例患者定期扩张尿道,总体效果满意。结论:尿道狭窄是TURP术后常见的并发症,其原因主要是医源性因素,需根据尿道狭窄的部位及程度选择适当的治疗方法。采取提高手术操作技能、加强尿管护理等措施有助于预防TURP术后尿道狭窄的发生。  相似文献   
83.
Currently used stents for malignant esophageal strictures include self-expanding metal stents (SEMS), self-expanding plastic stents (SEPS), and biodegradable stents. For the palliative treatment of malignant dysphagia, both SEMS and SEPS effectively provide rapid relief of dysphagia. SEMS are preferred over SEPS as randomized controlled trials have shown more technical difficulties and late migration with plastic stents. Despite specific characteristics of recently developed stents, recurrent dysphagia due to food impaction, stent migration, and both tumoral and nontumoral tissue overgrowths are common. Complication rates are probably also affected by stent “behavior” in the esophagus, with radial and axial forces being important determinants. The efficacy of stents with an antireflux valve for patients with distal esophageal cancer has not convincingly been proven. Concurrent treatment with chemotherapy and radiotherapy seems to be safe and effective, although biodegradable stents have shown disappointing results. It can be expected that removable stents will increasingly be used as bridge to surgery to maintain luminal patency during neoadjuvant treatment.  相似文献   
84.
Increasingly frequent dilation may become a self‐defeating cycle in refractory stricture as recurrent trauma enhance, scar formation, and ultimately recurrence and potential worsening of the stricture. In 12 patients of caustic induced esophageal stricture, who failed to respond despite rigorous dilatation regimen for more than one year, a trial of topical mitomycin‐C application to improve dilatation results was undertaken, considering the recently reported efficacy and safety of this agent. Mitomycin‐C was applied for 2–3 minutes at the strictured esophageal segment after dilation with wire‐guided Savary‐Gilliard dilator. Patient was kept nil by mouth for 2–3 hours. After 4–6 sessions of mitomycin‐C treatment, resolution of symptoms and significant improvement in dysphagia score and periodic dilatation index was seen in all 12 patients. Mitomycin‐C topical application may be a useful strategy in refractory corrosive esophageal strictures and salvage patients from surgery.  相似文献   
85.
Although balloon dilatation is the primary treatment for benign dysphagia, information about the optimal inflation time is lacking. The aim of the current pilot study was to compare 10 seconds inflation time with 2 minutes inflation time, regarding the efficacy. Twenty patients with symptomatic strictures were prospectively studied in a randomized fashion. The 10‐second group required an average of 1.4 dilations per patient; the 2‐minute group required an average of 1.5 dilations per patient. This pilot study indicates that 10 seconds inflation time is as effective as 2 minutes. Because the treatment is both painful and unpleasant, this is an important finding.  相似文献   
86.
Fibroblast infiltration and collagen deposition result in structural changes in the bowel wall, and lead to strictures in intestinal inflammatory disease. While strictures can also occur in other contexts, such as malignancy, this review focuses on the surgical treatment of stricture secondary to inflammatory bowel disease. Distinguishing between predominantly inflammation vs established fibrosis as the cause of a stricture can be challenging. While inflammatory strictures may be responsive to medication, predominantly fibrotic strictures usually need surgical intervention. Both endoluminal and extraluminal approaches are described in this review. Endoscopic dilatation of strictures is suitable for short‐segment isolated small bowel strictures. Other options are to divide the stricture surgically but preserve the length, performing a strictureplasty or resecting the strictured segment. The mesentery is increasingly recognized as playing a role in stricture recurrence. In a relapsing‐remitting disease such as Crohn's disease, the preservation of intestinal length is essential and balance is needed between this and a complete resection to reduce the risk of recurrence. Pre‐ and postoperative involvement of the multidisciplinary team is essential to improve outcomes in this challenging clinical scenario.  相似文献   
87.
BackgroundRemoval of biliary Fully Covered Self Expandable Metal Stents can fail due to stent migration and/or hyperplastic ingrowth/overgrowth.MethodsA case series of 5 patients with benign biliary strictures (2 post-cholecystectomy, 2 following liver transplantation and 1 related to chronic pancreatitis) is reported. The biliary stricture was treated by temporary insertion of Fully Covered Self Expandable Metal Stents. Stent removal failed due to proximal stent migration and/or overgrowth. Metal stent removal was attempted a few weeks after the insertion of another Fully Covered Metal Stent into the first one.ResultsThe inner Fully Covered Self Expandable Metal Stent compressed the hyperplastic tissue, leading to the extraction of both the stents in all cases. Two complications were reported as a result of the attempt to stents removal (mild pancreatitis and self-limited haemobilia).ConclusionIn the present series, the “SEMS in SEMS” technique revealed to be effective when difficulties are encountered during Fully Covered Self Expandable Metal Stents removal.  相似文献   
88.
Malignant gastric outlet obstruction(MGOO) is a clinical condition characterized by the mechanical obstruction of the pylorus or the duodenum due to tumor compression/infiltration, with consequent reduction or impossibility of an adequate oral intake. MGOO is mainly secondary to advanced pancreatic or gastric cancers, and significantly impacts on patients' survival and quality of life.Patients suffering from this condition often present with intractable vomiting and severe malnutrition, which further compromise therapeutic chances. Currently,palliative strategies are based primarily on surgical gastrojejunostomy and endoscopic enteral stenting with self-expanding metal stents. Several studies have shown that surgical approach has the advantage of a more durable relief of symptoms and the need of fewer re-interventions, at the cost of higher procedure-related risks and longer hospital stay. On the other hand, enteral stenting provides rapid clinical improvement, but have the limit of higher stent dysfunction rate due to tumor ingrowth and a subsequent need of frequent reinterventions. Recently, a third way has come from interventional endoscopic ultrasound, through the development of endoscopic ultrasound-guided gastroenterostomy technique with lumen-apposing metal stent. This new technique may ideally encompass the minimal invasiveness of an endoscopic procedure and the long-lasting effect of the surgical gastrojejunostomy, and brought encouraging results so far, even if prospective comparative trial are still lacking. In this Review, we described technical aspects and clinical outcomes of the above-cited therapeutic approaches, and discussed the open questions about the current management of MGOO.  相似文献   
89.
90.
AIM: To identify pharmaceuticals for the prophylaxis of anastomotic leakage (AL), we systematically reviewed studies on anastomosis repair after colorectal surgery.METHODS: We searched PubMed and EMBASE for articles published between January 1975 and December 2012. We included studies in English with the primary purpose of promoting healing of anastomoses made in the colon or rectum under uncomplicated conditions. We excluded studies on adverse events from interventions, nutritional interventions or in situ physical supporting biomaterials. The primary outcome was biomechanical strength or AL. We performed meta-analyses on therapeutic agents investigated by three or more independent research groups using the same outcome. The DerSimonian-Laird method for random effects was applied with P < 0.05.RESULTS: Of the 56 different therapeutic agents assessed, 7 met our inclusion criteria for the meta-analysis. The prostacyclin analog iloprost increased the weighted mean of the early bursting pressure of colonic anastomoses in male rats by 60 mmHg (95%CI: 30-89) vs the controls, and the immunosuppressant tacrolimus increased this value by 29 mmHg (95%CI: 4-53) vs the controls. Erythropoietin showed an enhancement of bursting pressure by 45 mmHg (95%CI: 14-76). The anabolic compound growth hormone augmented the anastomotic strength by 21 mmHg (95%CI: 7-35), possibly via the up-regulation of insulin-like growth factor-1, as this growth factor increased the bursting pressure by 61 mmHg (95%CI: 43-79) via increased collagen deposition. Hyperbaric oxygen therapy increased the bursting pressure by 24 mmHg (95%CI: 13-34). Broad-spectrum matrix metalloproteinase inhibitors increased the bursting pressure by 48 mmHg (95%CI: 31-66) on postoperative days 3-4. In the only human study, the AL incidence was not significantly reduced in the 103 colorectal patients treated with aprotinin (11.7%) compared with the 113 placebo-treated patients (9.7%).CONCLUSION: This systematic review identified only one randomized clinical trial and seven therapeutic agents from pre-clinical models that could be explored further for the prophylaxis of AL after colorectal surgery.  相似文献   
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