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排序方式: 共有7051条查询结果,搜索用时 15 毫秒
41.
Qian Z Maynar M Usón-Garallo J Sanchez-Margallo F Lima-Rodriguez MA Lima-Rodrigues JR Kim JK Gonzalez-Roman A Castañeda WR 《Academic radiology》1999,6(5):317-320
RATIONALE AND OBJECTIVES: The purpose of the study was to evaluate a method of producing obstruction of the common bile duct and concomitant biliary duct dilatation in an animal model. MATERIALS AND METHODS: Laparoscopic placement of a double-balloon occlusion device was used to produce common bile duct obstruction and bile duct dilatation in pigs. RESULTS: One week after the procedure, common bile duct obstruction and dilatation of the biliary tree were demonstrated with either percutaneous transhepatic cholangiography or percutaneous cholecystography. CONCLUSION: The use of this method is technically feasible and provides a useful subacute and chronic animal model of common bile duct obstruction and dilatation of the biliary tree for percutaneous interventional training and research purposes. 相似文献
42.
Novel imaging techniques for diabetic macular edema 总被引:2,自引:0,他引:2
Lobo C Bernardes R Faria de Abreu JR Cunha-Vaz JG 《Documenta ophthalmologica. Advances in ophthalmology》1999,97(3-4):341-347
Retinal edema should be defined as any increase of water of the retinal tissue resulting in an increase in its volume. It
may be of cytotoxic or vasogenic origin. Development of vasogenic macular edema is dependent on a series of factors such as
blood pressure, blood-retinal barrier permeability, retinal cell damage, retinal tissue osmotic pressure and retinal tissue
compliance. Objective measurements of retinal thickness are now possible using the Retinal Thickness Analyser. Localised measurements
of blood-retinal barrier permeability may also be obtained using the Retinal Leakage Analyser, a modified confocal scanning
laser fluorometer, while obtaining simultaneously angiographic images of the choroid and retina. These new imaging techniques
show that cytotoxic and vasogenic retinal edema may occur independently in the early stages of diabetic retinopathy. These
findings offer new perpectives for designing novel therapeutic strategies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
43.
Jose L. Ortiz José M. Vallés Miguel Martí-Cabrera Julio Cortijo Esteban J. Morcillo 《Naunyn-Schmiedeberg's archives of pharmacology》1996,353(2):200-206
There is currently interest in the potential use of selective inhibitors of cyclic nucleotide phosphodiesterases (PDE) in the treatment of asthma. In this study we examined the effects of three selective PDE inhibitors, milrinone (PDE III), rolipram (PDE IV) and zaprinast (PDE V), on the broncoconstriction produced by antigen and histamine, the airway hyperreactivity and microvascular leakage after aerosol exposure to platelet-activating factor (PAF) and antigen, and the antigen-induced eosinophil infiltration in guinea-pig lung. Inhaled rolipram (0.01–10 mg ml–1) inhibited dose dependently the bronchospasm produced by aerosol antigen (5 mg ml–1) an anaesthetised, ventilated guinea-pigs. Rolipram (10 mg ml–1) produced maximal inhibition of antigen-induced bronchoconstriction but only partial inhibition of the response to aerosol histamine (1 mg ml–1). Milrinone and zaprinast (each 10 mg ml–1) showed weak, or no, inhibitory effects against bronchoconstriction produced by aerosol antigen or histamine. Pretreatment with rolipram (10 mg kg–1, i.p.) prevented airway hyperreactivity to histamine which develops 24 h after exposure of conscious guinea-pigs to aerosol PAF (500 g ml–1) or antigen (5 mg ml–1). The pulmonary eosinophil infiltration obtained with 24 h of antigen-exposure was inhibited by rolipram. In contrast, milrinone and zaprinast (each 10 mg kg–1, i.p.) failed to reduce either the airway hyperreactivity of the eosinophil accumulation in these animals. Rolipram (1–10 mg ml–1) reduced the extravasation of Evans blue after aerosol PAF (500 g ml–1) at all airway levels while a lower dose (0.1 mg ml–1) was only effective at intrapulmonary airways. Rolipram (0.01–1 mg ml–1) markedly reduced airway extravasation produced by inhaled antigen (5 mg ml–1). Zaprinast (1–10 mg ml–1) was also effective against airway microvascular leakage produced by aerosol PAF or antigen while milrinone (10 mg ml–1) had no antiexudative effect. These data support previous suggestions that pharmacological inhibition of PDE IV results in anti-spasmogenic and anti-inflammatory effects in the airways and may be useful in the treatment of asthma. 相似文献
44.
E. Petzinger 《Naunyn-Schmiedeberg's archives of pharmacology》1981,316(4):345-349
Summary Cholic acid inhibits the uptake of demethylphalloin (DMP), in a competitive manner. The bile acid increases the Michaelis constant but not V
max of the inward transport. The inhibition constant K
i for cholate was found to be 8 M. Cholate competes for the transport system but not for intracellular binding of phallotoxins. Various experimental data presented in this paper exclude an accumulation of phallotoxins in hepatocytes by intracellular binding only.Preincubation of hepatocytes with small concentrations of either (3H)-demethylphalloin or (14C)-cholate and subsequent treatment with high concentrations of the nonlabelled compounds reduces the intracellular concentration of both radioactive substrates. In accordance with earlier findings the above results suggest a common component needed for the transport of both phallotoxins and cholic acid.This work was supported by the Deutsche Forschungsgemeinschaft 相似文献
45.
对肝外胆管梗阻时“软藤征”的再认识 总被引:5,自引:0,他引:5
本文回顾性分析了48例“软藤征”的病因,其中恶性疾病28例(占58.3%),良性疾病20例(占41.7%)。据本文资料,作者认为“软藤征”是肝管分叉部及肝外胆管急性完全(或接近完全)性梗阻时肝内胆管扩张的特征性X线表现,并非恶性梗阻特有,良性梗阻亦常见。作者指出,只要肝内胆管无或仅有轻度炎症,胆管具有良好的弹性和扩张性,不论良、恶性病变都可出现“软藤征”。那种认为当梗阻病变未显示时,仅根据“软藤征”即可作出恶性梗阻诊断的观点很值得商榷。作者认为,“软藤征”的定性及病因诊断主要应根据PTC或ERCP,或二者联合显示梗阻局部病变的形态学特征来确定。 相似文献
46.
47.
The aim of this article is to give a short review of problems associated with the intensive caretreatment of patients after esophageal resection.Pulmonary dysfunction,supraventricular tachyarrhyth-mia,anastomotie leakage and mental disorders are the topics covered.Systemic inflammatory reaction andsepsis is the linking topic between these specific complications.Pulmonary dysfunction having an incidenceof up to 40% is the most important complication.Low tidal volume ventilation,pain management includingepidural analgesia and early tracheostomy are the mainstay of therapy.Supraventricular tachyarrhythmiais an early indicator of emerging complications.Its symptomatic treatment is standardized using electriccardioversion,beta-blockers and amiodarone.Anastomotic leakage must be suspect in any septic episode.Endoscopy and contrast studies allow for precise diagnosis.Interventional endoscopy is increasingly suc-cessful in the therapy of these leakages.Microbiological surveillance and specific antibiotic therapy ensurethat a complication does not cause a septic cascade leading to multiorgan failure.The workload on ICUcaused by a patient after esophageal resection still exceeds that of most other patients with gastrointestinalsurgery. 相似文献
48.
216例恶性阻塞性黄疸患者手术疗效的因素分析 总被引:10,自引:0,他引:10
目的 探讨影响恶性阻塞性黄疸临床治疗的预后因素。方法 对1990年1月~1997年12月216例恶性阻塞性黄疸手术患者的17种临床指标进行分析。结果 173例(80.1%)手术后1个月存活,发生并发症81例,发生率37.5%。台术者胆管炎、胆瘘、出血、肾功能衰竭等并发症均高于姑息术者,差异均有显著性(P〈0.01);1月生存率和术后并发症发生率与ASA分级、黄疸持续的时间等有明显关系(P〈0.01 相似文献
49.
Subjective and functional results after total gastrectomy: prospective study for longterm comparison of reconstruction procedures 总被引:7,自引:0,他引:7
Shinya Adachi Satoshi Inagawa Tsuyoshi Enomoto Eiji Shinozaki Tatsuya Oda Toru Kawamoto 《Gastric cancer》2003,6(1):0024-0029
Background:
Many reconstruction procedures have been developed in efforts to resolve patients' complaints after total gastrectomy. However,
there have been few reports of longterm comparisons between reconstruction procedures, especially with regard to the prevention
of duodenal food passage. This study was undertaken to compare the longterm subjective and functional results among Roux-en-Y
esophagojejunostomy (R-Y), R-Y with pouch (P-Y), and jejunal interposition with pouch (P-I) after total gastrectomy.
Methods:
Consecutive patients requiring curative total gastrectomy were enrolled in this prospective study by the envelope method.
Results:
Hospital stay was longer following a P-I than an R-Y or a P-Y. Over 50% of R-Y patients complained of heartburn, and 20%
of R-Y patients showed dumping syndrome throughout the postoperative period, with this rate being significantly different
from rates in the other two groups. P-Y patients complained of early satiety in the late postoperative period, while P-I patients
complained of early satiety in the early postoperative period. The nutritional index in P-I patients was higher than those
in patients with the other two procedures. Gastrointestinal and hepatobiliary dual scintigraphy (GHDS) showed that the rate
of bile reflux with an R-Y was relatively high after surgery. Food reflux with a P-Y was increased (9.4% to 11.1%), but with
a P-I food reflux was decreased at 3 years after surgery (13.3% to 9.9%). Patients with a P-Y had a faster recovery of body,
weight in the early postoperative period; however, at 5 years after operation, body weight recovery with a P-I was greatest.
Conclusion:
Reconstruction should be performed with pouch formation after total gastrectomy with curative intent.
Received: March 7, 2002 / Accepted: September 26, 2002
Acknowledgments This study was partly supported by the University of Tsukuba Research Project.
Offprint requests to: S. Adachi 相似文献
50.
金属支架联合立体定向适形放疗治疗肝门部胆管癌 总被引:14,自引:0,他引:14
目的评价金属支架联合立体定向适形放疗肝门部胆管癌的疗效。方法31例肝门部胆管癌患者行金属支架置入联合立体定向适形放疗,并与23例行单纯支架治疗者进行对比研究。结果联合治疗组生存时间平均为11.1个月;对照组为5.1个月,差异有显著性意义(P<0.01)。结论胆道金属支架置入联合立体定向适形放疗是不能手术肝门部胆管癌的一种有效治疗方法。 相似文献