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71.
BACKGROUND: Little is known about the function of T cells in the inflammatory infiltrate in Helicobacter pylori-associated gastritis and B-cell lymphoma of mucosa-associated lymphoid tissue (MALT type). Previous studies have proposed a dominant Th1-type response in low-grade MALT lymphoma consistent with the Th1 response observed in H. pylori-associated gastritis. METHODS: We performed a novel flow cytometric approach in which CD3 panning for enrichment and activation of small numbers of T cells and intracellular cytokine analysis were combined to selectively characterize the cytokine profile of T cells (IFN-gamma for Th1) derived from the gastric mucosa of 23 patients with low-grade MALT lymphoma stage IEI1 (lymphoma infiltration of mucosa/submucosa sparing the muscularis). Endosonography was performed in each case to control the depth of lymphoma infiltration. For comparison, 19 patients with H. pylori-positive gastritis were also analysed. RESULTS: There was a CD4/CD8 ratio of 4 in patients with MALT lymphoma and of 2 in chronic gastritis. The proportion of IFN-gamma producing cells within the CD4-positive T-cell population in MALT lymphoma was 22%; in chronic gastritis it was 13% while no such difference could be encountered in CD8-positive T cells. CONCLUSIONS: The data point towards a dominant intratumoral IFN-gamma dominated T-cell response associated with early low-grade MALT lymphoma. A polarized IFN-gamma dominated Th1-type response may either contribute to the inability of the immune system to eradicate H. pylori infection, thereby promoting the activation status of the lymphocytic infiltrate in low-grade MALT lymphoma, or may mirror a concomitant tumor-specific T-cell response accompanying early stages of tumor progression.  相似文献   
72.
A randomised controlled multicentre trial was performed in 160 patients with gastric ulcer, proved by endoscopy and biopsy, to compare ulcer healing with sucralfate and ranitidine (double blind double dummy design) and to assess the effect of maintenance treatment with sucralfate on ulcer recurrence (double blind placebo controlled design). The healing rates were similar with 4 g sucralfate suspension per day and 300 mg ranitidine per day (82% and 88% after 12 weeks, respectively). Of the 109 patients with healed ulcers, 92 were entered into the maintenance trial and treated with sucralfate tablets (2 g per day) or placebo tablets. Maintenance treatment with sucralfate delayed symptoms of gastric ulcer recurrence. Lifetable analysis showed significant differences between sucralfate and placebo, both after six months (p = 0.018) and after 12 months (p = 0.044). The rates of symptom recurrences were 13% and 34% after six months and 34% and 55% after 12 months for sucralfate and placebo, respectively. The rate of asymptomatic recurrences after 12 months was similar in the two groups (9% and 10%, respectively). The recurrence rate was higher in patients who had never taken non-steroidal anti-inflammatory drugs than in those who had but had stopped on admission to the study. It was also higher in patients with recurrent ulcer and in those with scarring deformation and narrowing of the pylorus. Maintenance treatment with sucralfate slowed the appearance of symptom recurrences of gastric ulcer.  相似文献   
73.
Percutaneous transhepatic catheterization of the gallbladder for dissolution of cholesterol stones by instillation of methyl tert-butyl ether (MTBE) is an invasive therapeutic procedure. The only non-invasive alternative available to now, endoscopic retrograde cannulation of the cystic duct, was difficult because of the cystic duct's tortuosity and spiral valves. We therefore developed a catheter system which, using conventional duodenoscopes during a routine endoscopic retrograde cholangiography (ERC) procedure, permits reliable and safe catheterization of the gallbladder without the need for endoscopic sphincterotomy. In 18 of 22 patients (82%) we were able to place a cysto-nasal catheter, and in 14 patients MTBE dissolution therapy was then performed. Eight patients (57%) were completely free of stones after treatment; the other six (43%) had residual debris. In 4 of 22 patients (18%) cannulation attempts failed, in 3 patients due to cystic duct blockage by a calculus. Endoscopic retrograde cannulation of the gallbladder (ERCG) represents a promising alternative to the invasive percutaneous transhepatic catheterization procedure.  相似文献   
74.
75.
In three male duodenal ulcer patients, the effects of a 4-week treatment with a long-acting synthetic secretin -- daily s.c. administrations of 10 clinical units secretin/kg b.w. -- were assessed symptomatically, endoscopically, immunologically, and by means of gastric and pancreatic secretory analyses. Improvement in epigastric pain was noted within a few days following the onset of secretin therapy. In all cases, duodenoscopy revealed complete healing of ulcers after a 2- to 3-week treatment period. Before therapy, cutaneous anaphylactoid reactions due to intradermal injections of secretin could be elicited in each subject; skin reactions were found mitigated after 4 weeks of therapeutic secretin administration thus suggesting some desensitisation. Neither gastric acid secretion nor pancreatic bicarbonate production were substantially influenced by the 4-week course of secretin therapy; consequently, prevention of ulcer relapse is rather unlikely to be achievable with the conditions employed in this study. However, it seems therapeutically promising that the duodenal ulcers under study showed complete healing already after 2-3 weeks of secretin administration.  相似文献   
76.
Lysine acetylsalicylate (LAS), a water soluble derivative of acetylsalicylic acid and parenterally administrable analgesic, locally inhibits the incorporation of 14C protein hydrolysate into proteins of the rat isolated gastric mucosa. A similar effect on protein synthesis was observed after s.c. administration of the drug, whereas DNA and RNA synthesis were not affected. Obviously, LAS inhibits the translation step during biosynthesis of proteins. It is conceivable that this effect contributes to the potential ulcerogenic action of acetylsalicylate and that parenteral administration is not a criteria to protect the stomach from salicylate-induced side effects.  相似文献   
77.
Background: The accuracy of intraductal ultrasonography (IDUS) and endoscopic ultrasonography (EUS) were compared in diagnosing biliary obstruction and in predicting surgical resectability. Methods: Fifty-six patients with biliary obstruction were investigated preoperatively with both conventional EUS and IDUS. The ultrasonographic miniprobe was inserted into the bile duct system through the working channel of the duodenoscope during endoscopic retrograde cholangiopancreatography (ERCP). Conventional endosonography was performed with echoendoscopes in a standard technique. Images of endoluminal ultrasonography were prospectively reviewed and compared with intraoperative findings and resection specimen analyses. Results: IDUS exceeded EUS in terms of accuracy (IDUS, 89.1%; EUS, 75.6%; P < 0.002), sensitivity (IDUS, 91.1%; EUS, 75.7%; P < 0.002), specificity (IDUS, 80%; EUS, 75%; NS), and T-staging (IDUS, 77.7%; EUS, 54.1%; P < 0.001). In bile duct carcinomas the accuracy rate for lymph node staging using IDUS (60%) is comparable with that using EUS (62.5%). In pancreatic carcinomas, however, lymph node staging using IDUS (13.3%) is significantly (P < 0.002) inferior to EUS (69.2%). Endoluminal ultrasonography may predict the potential resectability of bile duct tumors (IDUS, 81.8%; EUS, 75.6%; P < 0.002). Conclusions: IDUS proved to be accurate in preoperative diagnosing and T-staging of malignant biliary strictures, whereas it is not suitable for lymph node staging. IDUS using miniprobes during ERCP exceeds conventional EUS in terms of depiction of bile duct obstruction, diagnostic accuracy, and sensitivity and in the prediction of surgical tumor resectability. Additionally, different to EUS, IDUS can conveniently be performed during ERCP in one and the same session.  相似文献   
78.
Background: Ultrasound-guided biopsies of abdominal organs are not without risks for the patients; in particular, hemorrhagic complications may occur. Thus, over the last few years, automatic biopsy guns have been developed to facilitate the biopsy process. Methods: The aim of our retrospective study was to examine the quality of specimens and the complication rate of ultrasound-guided biopsies of abdominal organs carried out in our institution using the automatic Autovac biopsy system during a period of 1.5 years. Of the total number of 321 biopsies, 290 were performed with the 1.2-mm Autovac needle, and in 31 cases the 0.95-mm needle was used. Among the 321 biopsies there were 211 of the liver parenchyma (66%), 47 of a liver tumor (14%), 38 of the pancreas (12%), 15 of the kidney parenchyma (5%), and 10 of a retroperitoneal tumor (3%). Results: In 310 of the 321 biopsies it was possible to obtain sufficient diagnostically usable material for the pathologist (96.6%). In the other 11 cases the material obtained did not enable proper histologic diagnosis (3.4%). Two of these 11 biopsies were carried out with the 0.95-mm needle, and the other 9 with the 1.2-mm needle.Twenty-four hours after the biopsy each patient underwent routine ultrasound examination to exclude a possible bleeding. In eight cases an afterbleeding occurred (total hemorrhagic rate, 2.5%), four times without clinical consequences. The other four bleeding complications were more serious (1.2% of all taps), and all occurred after liver biopsies in patients with a history of liver complaints and abnormal clotting variables. There were no fatalities among our biopsies (mortality rate, 0%). Conclusion: The automatic Autovac biopsy system is suitable and relatively safe for obtaining sufficient histopathologic material from intra-abdominal organs.  相似文献   
79.
Cystic lesions located in the gastric wall are a rare finding in endosonography of the gastrointestinal tract. Compared to all forms of benign and malignant tumours of the stomach, gastric duplication cysts are an uncommon anomaly – especially in adults. We report on a 59-year-old woman suffering from intermittent abdominal pain, weight loss and nausea. A gastric duplication cyst was identified by endoscopic ultrasound (EUS), but malignancy was excluded by EUS and fine-needle aspiration histology. Because of continuously increasing abdominal complaints, surgery was performed with partial resection of the gastric corpus and splenectomy. Gross anatomy and histology showed a gastric cyst measuring 150 mm in maximum diameter with no evidence of malignancy or inflammation. Following surgery, the patient's condition recovered fully.  相似文献   
80.
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