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71.
Localization of small intestinal bleeding 总被引:1,自引:0,他引:1
The preoperative identification of a bleeding site is not always possible, particularly when bleeding originates in the small intestine. Small vascular abnormalities, such as the telangiectatic lesion described in this report, comprise about 40–60% of such cases. Preoperative location using arteriography, radionuclide bleeding scan, and enteroclysis were nondiagnostic. The lesion was demonstrated by intraoperative endoscopy. A segment of small intestine was resected, and the patient made an uneventful recovery. 相似文献
72.
Light-emitting diodes and half-cell electrodes in experimental recording of electroretinogram c-wave
Marko Hawlina MD Peter L. G. De Villiers 《Documenta ophthalmologica. Advances in ophthalmology》1992,81(2):227-237
A method of electroretinogram c-wave recording in the rat was developed that uses a contact lens electrode connected through a saline bridge with a silver-silver chloride half-cell. A cluster of light-emitting diodes, regulated by an electronic light-emitting diode stimulator, was used as a light source. The method enables recordings of c-waves of 0.4–1.6 mV amplitude as well as other electroretinogram components in narrow limits of variation. The two main sources of response variability are voltage shunting and eyeball protrusion. 相似文献
73.
F. Bossa G. Cocomazzi M.R. Valvano A. Andriulli V. Annese 《Digestive and liver disease》2006,38(8):599-602
BACKGROUND AND STUDY AIM: Capsule endoscopy is a non-invasive technique for small bowel examination but its evaluation is time consuming. The aim of this study was to assess whether, following adequate training, an endoscopy nurse is capable of picking up all significant images without reducing the diagnostic accuracy of the procedure. PATIENTS AND METHODS: Between April 2003 and December 2004, a total of 41 consecutive capsule endoscopy studies were blindly reviewed by both an endoscopy nurse and an endoscopist. The two operators had to select all significant images independently and to complete a structured questionnaire. Thirty-nine capsule endoscopy examinations (two studies discharged for premature battery failure) were evaluated. The agreement between the two operators was calculated by kappa statistics (coefficient of agreement). RESULTS: Agreement was excellent for all kind of selected lesions (mean kappa>0.85); the agreement was complete (kappa=1) for site identification, active bleeding, stenosis and negative studies. The greater disagreement (kappa=0.77) was found in cases of subtle mucosal abnormalities (i.e. reduction of villi), which were over-estimated by the nurse. CONCLUSIONS: The preview recordings made by the nurse may increase the cost/effectiveness of the study, by considerably reducing the time needed for the endoscopist to make the final report (about 5-10 min), without compromising final diagnosis. 相似文献
74.
Michelle Lucinda DeOliveira M.D. Tarcisio Triviño M.D. Ph.D. Gaspar de Jesus Lopes Filho M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(8):1140-1143
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies.
Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable
than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor,
although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis
of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance
and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with
final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison
was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy
were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although
preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value
of the endoscopic appearance was superior to endoscopic biopsy in this series.
Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003.
Supported by FADA-CAPES/PROP 200J (M.L.D.). 相似文献
75.
R. Kapoor R. Pradeep S. S. Sikora R. Saxena V. K. Kapoor S. P. Kaushik 《ANZ journal of surgery》1994,64(9):599-603
One hundred and ten patients with common bile duct (CBD) stones were treated in the Department of Surgical Gastroenterology at SGPGIMS, Lucknow, India between January 1989 and December 1992. The primary modality of treatment was surgery in 62 patients (group I) and endoscopic sphincterotomy (ES) in 48 (group II). The two groups were well matched with respect to clinical features and presence of medical risk factors. Surgical clearance of CBD stones was achieved in 58 patients (93.5%; group Ia). Four patients (7%) had retained stones following surgery (group Ib). In group II, the CBD was cleared by endoscopic means in 20 out of 48 patients (42%) and was categorized into group IIa. In the remaining patients ES was followed by CBD exploration (group IIb). Significantly higher morbidity was seen in patients needing CBD surgery following attempted endoscopic clearance, because of ES-related complications, such as bleeding, cholangitis, septicaemia and numerous others. Use of ES to treat CBD stones on a routine basis was therefore not found to be any better than one-time surgical exploration. 相似文献
76.
A case history of a 32-year-old female Olympic pole vaulter is reported. Two months after endoscopic surgery for chronic Achilles tendinopathy, she developed a keloid lesion on the hindfoot area. She was treated with corticosteroids, topical and intralesional injections. A satisfactory result was obtained, and the athlete was able to resume her competitive activity at 5 months after surgery. Keloid pathogenesis, treatment, and prevention are briefly discussed. 相似文献
77.
Nuthapong Ukarapol Nirush Lertprasertsuk George J. Fuchs Lumduan Wongsawasdi Virat Sirisanthana 《Digestive endoscopy》2004,16(1):26-29
Objective: To evaluate the role of gastrointestinal (GI) endoscopy in human immunodeficiency virus (HIV)‐infected children with GI problems. Methods: From 1998 to 2002, we retrospectively reviewed all cases of HIV‐infected children presenting with GI problems in which an upper or lower GI endoscopy was indicated. The initial diagnostic endoscopic examination and any repeat endoscopic session leading to a new diagnosis were used in the data analysis. Tissue biopsies were obtained from all abnormal lesions and representative sites of normal‐appearancing GI mucosa. Results: Fourteen patients (median age: 22.5 months) underwent 23 sessions of GI endoscopy, including 10 esophagogastroduodenoscopy, nine colonoscopy and four flexible sigmoidoscopy. Chronic diarrhea was the most common indication, followed by lower GI bleeding, abdominal/retrosternal pain, dysphagia/odynophagia, and upper GI bleeding. Gross endoscopic abnormalities were observed in 78.3%; whereas histological inflammation and opportunistic pathogens were identified in 87% and 43.5%, respectively. Cytomegalovirus was the most common identified pathogen. Abnormal gross findings were significantly associated with histological inflammation and identification of pathogens (P = 0.006 and 0.046, respectively). Specific changes in medical management were made in 50% of cases as a result of endoscopic investigation. Conclusion: If non‐invasive investigations for HIV‐infected children with GI symptoms fail to establish a diagnosis, gastrointestinal endoscopy should be performed and often yields a positive result leading to changes in medical management. 相似文献
78.
强脉冲光对大鼠皮肤胶原蛋白影响的定量分析 总被引:14,自引:0,他引:14
目的 定量分析强脉冲光对大鼠皮肤胶原蛋白含量的影响,进一步明确强脉冲光在治疗皮肤光老化中的作用机制。方法 选择15只SD大鼠,每只选3个部位用强脉冲光治疗,采用同一治疗参数,能量密度34J/cm2 ,分为3个脉冲,脉宽各为4ms、5ms、6ms,脉冲延时为2 0ms及2 5ms。分别切取治疗后第1、3、5、7、15、30天皮肤和未治疗部位皮肤,进行组织学观察。结果 治疗后,第1、3、5、7天皮肤胶原蛋白染色与未治疗部位比较无明显差别,第15天强于未治疗部位,第30天明显强于未治疗部位,免疫组化染色Ⅰ、Ⅲ型胶原明显增多(P <0 .0 0 1)。结论 强脉冲光治疗大鼠皮肤后可引起胶原含量的增加,在实验基础上为强脉冲光的临床应用提供了理论依据。 相似文献
79.
Background and Objective: Although the empirical characteristics of ArF excimer laser corneal ablation have been well documented, the exact ablation mechanisms are not well understood. The present paper reports a quantitative analysis of corneal ablation plumes using in situ time resolved laser light scattering and Raman spectroscopy. Study Design/Materials and Methods: Bovine corneas were used as the ArF excimer laser ablation targets. Light scattering data were recorded from the ablation plume as a function of height above the tissue surface and as function of delay time with respect to the ablative ArF laser pulse. Results: Raman spectra of the ablation plume allow identification of the particles as water. Mean plume particle diameters are found to decrease with height, while the particle volume fractions are relatively constant. The total volume of plume particles correlates well with the total volume of water in the ablated corneal tissue. Conclusion: The finding of a non-evolving plume composed of water spherules, combined with the excellent agreement between total volume of water in the plume and the content of water in the ablated corneal tissue, support the concept of photodecomposition or “cold ablation” for corneal tissue during ArF excimer laser ablation. © 1995 Wiley-Liss, Inc. 相似文献
80.
合成了稀土(Ln)与2,2-联吡啶(L1)、1,10-菲罗啉(L2)的三元固态配合物。通过元素分析、IR谱、TGA谱和摩尔电导等对该系列配合物进行了表征,实测结果与通式LnL1L2Cl3·3H2O符合较好。抗菌试验表明,该系列配合物有较强的广谱抗菌作用。 相似文献