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41.
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.  相似文献   
42.
Summary:  The goal of this study was to develop a new model of ischemia-induced seizures in immature rats using injection of vasoconstrictor Endothelin-1 (ET-1) into the brain. ET-1 (10, 20, or 40 pmol) was infused into the left dorsal hippocampus of freely moving Wistar rats 12 (P12) and 25 (P25) days old. Animals were then video/EEG-monitored for 100 min and monitoring was repeated 22 h later. Parameters of electrographic seizures (frequency and mean duration) as well as pattern of their behavioral correlates were evaluated. The pattern of behavioral seizures was used to develop model-specific scoring system. Cresyl violet and Fluoro Jade-B-staining were used to evaluate brain damage. Extension of the lesion was correlated with seizure severity. After ET-1-injection, seizures occurred in 83–100% animals of all age-and-dose groups and persisted for 24 h except P12 rats with 10 pmol. There were no differences in average seizure duration (18–40 s) or seizure frequency (3–7 seizures/100 min) among individual dose-groups. Between the 1st and 2nd observation period, total seizure duration decreased in 71% of P12 and 47% of P25 rats. Electrographic seizure activity was most frequently accompanied by clonus, incidence of more severe convulsions (barrel rolling or generalized clonic seizures) increased with dose of ET-1. Morphologic examination did not reveal any dose-related difference in damage severity, hippocampal damage was however more extensive in P12 compared to P25 animals. Seizure severity correlated positively with severity of the damage in both age groups. Our study presents focal injection of ET-1 into the brain as a new and practical model of ischemia-induced seizures in immature rats.  相似文献   
43.
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer.  相似文献   
44.
BACKGROUND: Traditionally patients with a high rectosigmoid carcinoma and a synchronous large distal rectal adenoma would be treated by low anterior resection with associated loss of rectal function. METHOD: Four patients with a carcinoma of the upper rectum or distal sigmoid colon and a synchronous distal rectal adenoma were treated by high anterior resection followed by staged Transanal Endoscopic Microsurgery (TEM) thus conserving the distal rectum. Preoperative and postoperative rectal function was assessed using the St. Mark's incontinence score. RESULTS: The proximal carcinomas and distal adenomas were 12-18 cms and 0.5-9 cms respectively from the dentate line. The mean surface area of the distal adenomas was 9.7 cms2. There were no deaths or major complications. There were no recurrences after a mean follow-up of 31.5 months. Rectal function was unchanged in three patients with a minor increase in the score in one. CONCLUSION: Staged high anterior resection and 'rEM offers effective treatment of synchronous rectosigmoid carcinoma and distal rectal adenoma with preservation of rectal function.  相似文献   
45.
46.
电视硬质气管镜治疗大气道良性肿瘤   总被引:4,自引:4,他引:0  
目的探讨电视硬质气管镜在大气道良性肿瘤治疗中的价值.方法2002年9月~2005年4月,我院应用电视硬质气管镜治疗大气道良性肿瘤7例,其中气管1例,隆突1例,左主支气管3例,右主支气管2例.手术采用静脉全身麻醉,喷射通气供氧,探查评估气道后,首先冷冻或电凝肿瘤,破坏肿瘤血供,再以活检钳分块取出,蒂部采用冷冻或氩气凝固处理;对于宽蒂肿瘤,内镜下将肿瘤主体清除后中转开胸行气管局部切除吻合术.结果7例手术均顺利,无一例死亡和严重并发症发生.6例气管窄蒂良性肿瘤镜下完整摘除,1例气管膜部宽蒂平滑肌瘤先内镜清除肿瘤主体后中转开胸行气管局部切除.术后病理为错构瘤2例,平滑肌瘤3例,嗜酸性肉芽肿性腺瘤1例,炎症组织1例.7例随访3~36个月,平均17.3月,无肿瘤复发.结论电视硬质气管镜治疗大气道良性肿瘤安全可靠.  相似文献   
47.
OBJECTIVE: Pediatric gastric access for long-term enteral feeding may be performed via a laparotomy, laparoscopy, or a percutaneous approach. In children and adolescents, laparoscopic-assisted gastrostomy may be difficult due to a thick abdominal wall. Therefore, if the abdominal wall is estimated to be >2 cm on physical examination, or in children in whom a percutaneous endoscopic gastrostomy was unsuccessfully attempted by a gastroenterologist, we routinely perform a laparoscopic-assisted percutaneous endoscopic gastrostomy. METHODS: From January 1998 through February 2003, we retrospectively reviewed 15 cases of a laparoscopic-assisted percutaneous endoscopic gastrostomy. Instruments used to perform this technique are a percutaneous endoscopic gastrostomy kit, an Olympus flexible endoscope, and one 5-mm STEP port placed through an infraumbilical incision for a 5-mm, 30-degree scope. RESULTS: Age range was 2 years to 20 years (mean, 10). Operative time ranged from 20 minutes to 45 minutes. When a concurrent laparoscopic Nissen fundoplication was performed (n = 6), the percutaneous endoscopic gastrostomy was placed after completion of the Nissen fundoplication. No intraoperative complications occurred, and all tubes were successfully placed. Feeds were instituted the following day and advanced to goal. To date, no postoperative complications have occurred, and revision has not been necessary. CONCLUSIONS: Laparoscopic-assisted percutaneous endoscopic gastrostomy in children and adolescents is safe and effective. Utilizing laparoscopy permits evaluation of the peritoneum and lysis of adhesions, if necessary. Moreover, laparoscopy provides excellent exposure for accurate placement of the PEG, while avoiding injury to other organs.  相似文献   
48.
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.  相似文献   
49.
电视胸腔镜辅助胸壁小切口肺叶切除术   总被引:13,自引:0,他引:13  
目的比较电视胸腔镜辅助胸壁小切口与胸部单纯小切口肺叶切除术的临床效果. 方法 64例按手术先后顺序编号,按照随机数字表分为2组,电视胸腔镜辅助胸壁小切口(A组)和单纯小切口开胸手术(B组)进行肺叶切除术. 结果 A组切口长度(5.3±0.6)cm比 B组(8.9±0.5)cm显著缩短(t=-24.360,P=0.000);A组术中出血量(279.7±74.0)ml显著少于B组(331.7±42.5)ml(t=-3.330,P=0.002);A组手术当日引流量(162.5±47.4)ml显著少于B组(202.0±49.2)ml(t=-3.220,P=0.002);A组并发症5例,B组11例(χ2=4.099,P=0.043);A组术后住院(8.0±2.2)d显著短于B组(9.7±1.9)d(t=-3.280,P=0.002);2组手术时间无统计学差异(t=-1.130,P=0.262).57例随访6~12个月,术后6个月A组1例Ⅲa期鳞癌局部复发,B组2例Ⅲa期小细胞肺癌、1例腺癌术后7~8个月远处转移、局部复发,上述4例均于1年内死亡.3例死于与手术无关的其他疾病,余50例无局部复发、远处转移. 结论电视胸腔镜辅助胸壁小切口比单纯微创小切口进行肺叶切除术创伤小、并发症少、恢复快.  相似文献   
50.
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.  相似文献   
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