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排序方式: 共有1700条查询结果,搜索用时 15 毫秒
1.
Endoscopic alternatives in the management of colonic strictures 总被引:10,自引:0,他引:10
A 10-year review of our experience with all patients with symptoms of colonic narrowing (n = 61) revealed 14 patients who were treated endoscopically. The site of narrowing was the sigmoid colon in 12 patients and the rectum in two patients. The strictures occurred after anastomosis in seven patients, with carcinoma in four patients, and with inflammatory disease, external compression, and idiopathy in one patient each. Although combinations of endoscopic techniques were occasionally used, the predominant method responsible for successful management of the narrowing was bouginage in four patients, endoscopy with a prototype dilating endoscope in four patients, balloon dilatation in three patients, and electrocautery and laser surgery in one patient each. There were no perforations or bleeding complications. Repeated treatments were usually needed. As less invasive methods evolve to treat colonic narrowing, appropriate matching of available techniques with the underlying disease becomes easier. We have found that dilation with a bougie, balloon, or a prototype dilating endoscope can provide especially beneficial results when used on patients with strictures resulting from inflammatory disease or external compression. Cutting and ablating tools such as the electrocautery and laser tools are more suited for management of strictures that result from carcinoma and anastomotic webs. Appropriate matching of endoscopic technique to underlying colonic pathology will allow increasingly successful and safer management of colonic narrowing without operation. 相似文献
2.
Baki Hazer Alipaa Ayas Necati Beirli Necdet Saltek Bahattin M. Baysal 《Macromolecular chemistry and physics.》1989,190(8):1987-1996
Some new macroinitiators ( 5 ) containing azo and peroxy groups were synthesized by transformation of esters of poly(ethylene glycol) ( 1 ) (PEG) of different molecular weight with hydroxyl end groups and an azo group in the middle into the corresponding polymers with tert-butylperoxycarbonyl end groups by reaction with terephthaloyl chloride and subsequently with tert-butyl hydroporoxide. Decomposition in the presence of styrene at 60°C or with 3,6,9-triazaun-decane-1,11-diamine in presence of methyl methacrylate gave the corresponding ABA block copolymer 6 and the ABBA block copolymer 7 , respectively. Both block copolymers were used as polymeric initiators. The ABCBA block copolymer 8 was synthesized from 6 and methyl methacrylate or from 7 and styrene by thermally induced polymerization at 80°C. The resulting block copolymers were separated from the homopolymers by selective solvent extraction and characterized by spectroscopic and fractional precipitation methods. 相似文献
3.
Which patient, which pump? 总被引:1,自引:0,他引:1
4.
Nadir Y?net?i Nevin Oru? A Omer Ozütemiz Kamil Kumanlioglu Gül Yüce Yücel Batur 《Experimental and toxicologic pathology》2002,54(3):197-201
BACKGROUND: Many interrelationships exist between the thyroid gland and the gastrointestinal tract. Several past and recent studies have shown that the thyroid gland profoundly influences the structure and function of the exocrine pancreas in the rat. In the present study we investigated the effect of methimazole (METZ), an antithyroid drug, on cerulein induced acute pancreatitis (AP) in rats. METHODS: Rats were divided into 3 groups (10-12 weeks age, 200-250 g weight, n: 10). Group B was made hypothyroid with methimazole 5 mg/kg daily for 10 days and the others were untreated euthyroid groups. After 10 days, acute pancreatitis was induced with four doses of 20 microg/kg body weight of cerulein administered s.c at hourly intervals in group A and B while the control group C was given 4 doses of I ml saline. Pancreas wet weight (mg), plasma amylase activity (IU/l) and pancreatic histology were used as endpoints to quantify the severity of the AP. RESULTS: Plasma tri-iodothyronine (T3) (ng/dl) and thyroxine (T4) (microg/dl) levels were significantly reduced after METZ treatment for 10 days (p < 0.01). METZ pretreatment reduced significantly the cerulein induced increase in pancreatic weight (1,205 +/- 12 mg in METZ treated AP group versus 1,617 +/- 14 mg in AP group, p < 0.05) and the rise in amylase activity (7,078 +/- 816 IU/l in METZ treated AP group versus 8,611 +/- 830 IU/l in AP group p < 0.05). CONCLUSION: METZ reduces the severity of cerulein induced AP in rats. This effect might be through its antithyroid property. 相似文献
5.
Jeffrey A Morgan Ranjit John Yookyung Park Linda J Addonizio Mehmet C Oz Niloo M Edwards Jan M Quaegebeur Ralph S Mosca 《The Journal of heart and lung transplantation》2005,24(1):58-62
BACKGROUND: Many cardiac transplant programs have liberalized donor eligibility criteria in an attempt to maximize donor supply and to accommodate increasing demand. Although many studies have evaluated the potential adverse effects of prolonged donor ischemic time (DIT) in adults undergoing cardiac transplantation, relatively few have focused specifically on pediatric recipients that include a substantial number of patients and long-term follow-up. The focus of this study was to examine the effect of extended DIT on mortality after pediatric heart transplantation. METHODS: We conducted a retrospective review of our pediatric cardiac transplant experience in the past 11 years, comparing patients who received allografts and had ischemic times >240 minutes with those who had ischemic times <240 minutes. RESULTS: A total of 129 pediatric patients (<19 years) underwent orthotopic heart transplantation, of whom 78 (60.5%) had DIT <240 minutes and 51 (39.5%) had DIT >240 minutes. We found no statistically significant difference in age, sex, race, height, weight, or donor age between the groups (p = not significant). Post-transplant survival at 1, 5, and 10 years was similar for both groups: 91.2%, 88.0%, and 85.2%, respectively, for patients with DIT <240 minutes vs 89.6%, 87.2%, and 79.8%, respectively, for patients with DIT >240 minutes (p = 0.433). Additionally, using Cox proportional hazard models, extended DIT >240 minutes was not a statistically significant independent predictor of post-transplant mortality (odds ratio, 0.655; 95% confidence interval, 0.518-0.972; p = 0.684; standard error = 0.468). CONCLUSION: Procurement of hearts from distant locations with associated extended DIT is justified in the setting of increased demand and a fixed donor population. 相似文献
6.
Misdiagnosed fibrosarcoma of the mandible mimicking temporomandibular disorder: a rare condition. 总被引:1,自引:0,他引:1
Kaan Orhan Ay?e Isil Orhan Ula? Oz Filiz Namdar Pekiner Cagri Delilbasi 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(4):e26-e29
The jawbones can be sites of various neoplastic conditions. Given the variety of processes affecting this particular anatomical area, formulation of a precise diagnosis can be challenging to clinicians. Limited jaw movement, pain, and facial asymmetry are common signs among patients, especially those with temporomandibular disorder (TMD). This paper reports a case of primary fibrosarcoma affecting the mandible and surrounding structures in a 14-year-old girl presenting signs and symptoms similar to TMD. Her condition was misdiagnosed, and she was treated for TMD over an extended period before the correct diagnosis was made for fibrosarcoma. The patient underwent surgical resection with postsurgical radiotherapy and chemotherapy and now is being followed up. Although malignant lesions are rare in the temporomandibular joint (TMJ) region, dentists are advised to be aware of the condition and to keep in mind that patients who are admitting for TMD can also possibly be affected from neoplasms. Hence, those patients have to be examined meticulously to avoid misdiagnosis and mistreatment. 相似文献
7.
8.
A huge and extremely organoid mass, protruding from the mouth of a newborn and causing respiratory embarrassment, was resected. It was difficult to make a clear distinction whether this mass was fetus in fetu or a highly organoid epignathus dealing with the findings obtained from its gross and histological examination of the mass. 相似文献
9.
R C Ashton M C Oz J F Lontz M Matsumae R Taylor G M Lemole N Shapira G M Lemole 《The Journal of surgical research》1991,51(4):324-328
Characterization of the stress-strain profiles of welded tissue would provide an additional means of analyzing this new technology and comparing it with alternative anastomosing techniques. Rabbit longitudinal aortotomies were repaired with either 7-O polypropylene sutures or an 808-nm diode laser (power density, 4.8 watts/cm2) after topical application of fibrinogen mixed with indocyanine green dye (peak absorption, 805 nm). The rabbits were sacrificed between 0 and 28 days, and the fresh aortic specimens were strained axially in diluted plasma solution until ultimate breakage occurred in order to produce a stress-strain profile graph. No significant differences were noted between sutured and bonded aorta at any time interval. Nonincised aortic tissue (378 lb/in2) withstood significantly higher stress (P less than 0.05) than both sutured (257 lb/in2) and bonded (210 lb/in2) groups at the time of creation. By 7 days after operation, however, no significant differences were noted among any of the three groups. At 28 days after operation, the laser-bonded aorta was significantly stronger than the control aorta (P less than 0.05). The only significant difference in modulus (stretchability) identified the sutured aorta (373 lb/in2) to be more rigid than the control aorta (231 lb/in2) (P less than 0.05). Both sutured and laser-bonded anastomoses are weaker than control aorta initially; however, after an early critical period, both treatments achieve the strength of control aorta. By 1 month postoperatively, sutured anastomoses have the disadvantage of being less distensible. 相似文献
10.
Attempts to improve the speed and patency of microvascular anastomosis with laser-assisted techniques have provided a modest reduction in operative time and comparable success rates. Using sutureless microvascular anastomoses, 30 end-to-end anastomoses were created in the rat carotid artery using the gallium-aluminum-arsenide diode laser (808 nm). Indocyanine green and fibrinogen were applied to enhance tissue absorption of the laser energy and strengthen the bond created. These were compared with previously reported welds using the THC:YAG laser (2150 nm). Mean welding times were 140 and 288 s, and mean bursting pressures immediately after welding were 515 and 400 mmHg for the diode and THC:YAG laser groups, respectively. Histologically, both lateral and vertical spread of thermal damage was limited. Since both lasers create welds of adequate initial strength without stay sutures and are faster and easier to use than existing systems, evaluation of long-term patency would be worthwhile. 相似文献