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41.
42.
To determine if and how clonidine and tricyclic antidepressants affect gastric contractility. Guinea pig fundic and antral circular muscle strips were studied in vitro. The effects of clonidine or amitriptyline added in graded concentrations on contractions to electric field stimulation (EFS), acetylcholine (ACh), and SP in the presence of N(epsilon)-nitro-l-arginine methyl ester (l-NAME) were studied. EFS produced frequency dependent contractions of fundic and antral muscle that were abolished by atropine or tetrodotoxin (TTX). ACh contractions were abolished by atropine but not TTX. Clonidine reduced contractile response to EFS but had no effect on ACh contractions. The threshold concentration of clonidine to inhibit EFS contractions was lower in the fundus than in the antrum. Amitriptyline reduced contractions to both EFS and ACh but not to SP. The threshold concentration of amitriptyline to inhibit EFS contractions was lower in the antrum than in the fundus. Both clonidine and amitriptyline affect gastric contractility. At threshold concentrations, clonidine affects fundic contractility whereas amitriptyline affects antral contractility. Clonidine affects gastric contractility in response to EFS but not to ACh, suggesting alpha-2 receptors on cholinergic nerves that reduce ACh release. Amitriptyline inhibits gastric contractility to EFS and ACh suggesting an inhibitory muscle effect. 相似文献
43.
S. Carmagnola P. Cantù D. Savojardo M. Allocca & R. Penagini 《Neurogastroenterology and motility》2004,16(3):287-292
A simple and reliable experimental model would be useful in human research on new drugs which target transient lower oesophageal sphincter (LOS) relaxation. The aim was to investigate the effect of repeated distensions on the rate of transient LOS relaxation, LOS pressure and motor function of the proximal stomach. Twelve healthy subjects were studied with a multilumen manometric assembly incorporating a sleeve sensor for the LOS and a bag positioned in the proximal stomach and connected to a barostat. Intrabag volume was set at 75% of the threshold for gastric discomfort and maintained for two 30-min distension periods separated by a 45-min washout with the bag deflated. The studies lasted 145 +/- 2 min. The rate of transient LOS relaxations was similar during the two distensions, 3.5;2-4 vs 3;2.5-4 (median;interquartile range) and so was LOS pressure. Baseline intrabag pressure, as a measure of gastric tone, and the number of pressure waves, as a measure of phasic contractions, were also similar, 11.3;9.3-12.3 mmHg vs 10.8;9.3-12.5 mmHg and 16;13-28 mmHg vs 19;15-29 mmHg, respectively. Our model allows to perform 1-day studies which can assess two experimental conditions on transient LOS relaxations and motor function of the proximal stomach within an acceptable time span. 相似文献
44.
TheClinicalEfectsofAlantoinPowderforGargleonPeriodontalDiseasesandAphthousUlcerYuWeiyi(俞未一)SunWeibin(孙卫斌)DepartmentofStomatol... 相似文献
45.
Takeo MAEKAWA Kiyotaka YABUKI Koichi SATO Takanori HABA Kaoru OGAWA Michio MATSUMOTO 《Digestive endoscopy》1998,10(1):46-50
Abstract: A 63-year-old man was hospitalized because of jaundice and anorexia. An upper gastrointestinal series and hypotonic duodenography revealed circumferential sclerosis and stenosis of the duodenal wall. Endoscopic examination disclosed an ulcer, the upper margin of which was located at the papilla of Vater. The papilla was situated in the base of the ulcer. Endoscopic retrograde cholangiopancreatography disclosed mild dilatation of the common bile, intrahepatic bile and pancreatic ducts, but with neither severe stenosis nor occlusion. Nevertheless, there was some degree of circumferential compression and mild stenosis of the terminal portions of the bile and pancreatic ducts, as potential causes of obstructive jaundice in this patient. Computed tomographic examination of the abdomen revealed a tumorous lesion at the duodenal bulb. Because malignancy in the duodenum could not be ruled out, a pancreatoduodenectomy was performed. Histopathological examination showed a postbulbar duodenal ulcer, associated with inflammation of the papillary orifice and fibrosis of the region near the papilla. There was no evidence of a tumorous lesion. In this case, a postbulbar duodenal ulcer may have caused obstructive jaundice. 相似文献
46.
MASASHI YOSHIDA GO WAKABAYASHI HIDEKI ISHIKAWA YOSHIHIDE OTANI MOTOHIDE SHIMAZU TETSURO KUBOTA KOICHIRO KUMAI IWAO KUROSE SOICHIRO MIURA HIROMASA ISHII MASAKI KITAJIMA 《Journal of gastroenterology and hepatology》1998,13(1):104-108
The effects of camostat mesilate, a synthetic serine protease inhibitor on gastric microcirculation and active oxygen species generated by leucocytes from the gastric and jugular veins in the early period after thermal injury were assessed. Male Wistar rats were anaesthetized and a 30% full skin-thickness dorsal burn was inflicted. Camostat mesilate (100 mg/kg) was dissolved in distilled water and administered orally to rats 40 min before thermal injury (the camostat group). The control animals (the vehicle group) were administered distilled water orally. Rolling leucocytes as well as Monastral blue B deposits in venules were observed using in vivo microscopy. Active oxygen species were measured by chemiluminescence. Camostat mesilate decreased the total length of gastric erosion, venular deposits of Monastral blue B, and rolling of leucocytes in venules, and relatively increased luminol-dependent chemiluminescence activity generated by zymosan-stimulated leucocytes 15 min after thermal injury. These results suggest that serine proteases are involved in the formation of gastric erosions and gastric microcirculatory disturbance in the early period after thermal injury. 相似文献
47.
Combined laparoscopic and endoscopic treatment of perforated gastroduodenal ulcer using the ligamentum teres hepatis (LTH) 总被引:2,自引:2,他引:0
We propose a novel technique for laparoscopic treatment of perforated gastroduodenal ulcers. The principle of this procedure involves the closure of the perforated ulcer using the ligamentum teres hepatis (LTH). The LTH is cut near its umbilical end and then dissected up to the site of its hepatic insertion. The umbilical extremity of LTH is grasped with a Dormia noose passed through the ulcerated perforation via a gastroscope. Using the noose, the LTH is pulled through the ulcerated perforation until its volume fits and completely closes the perforation. This laparoscopic technique was performed in 15 patients (12 M, 3 F) with anterior perforated duodenal ulcer revealed within the previous 6 h. The procedure could not be performed in three cases: diameter of the perforation exceeding 1.5 cm (n=1), general purulent peritonitis (n=2). In the other 12 cases, closure of the ulcerated perforation with the LTH was realized without technical difficulty. The postoperative course was uncomplicated. The posttreatment comfort was excellent; the mean period of hospitalization was 10 days (range, 8–14 days). An endoscopic examination carried out following 5 weeks of anti-H2 treatment showed that cicatrization of the ulcer was good and that no pyloric stenosis remained. These initial results suggest that laparoscopic treatment of perforated gastroduodenal ulcer using the LTH is a simple procedure which can be performed with general assurance of success in patients whose perforated ulcers have occurred quite recently. As the laparoscopic procedure is less aggressive than a laparotomy, it enhances the postoperative comfort of patients and prevents the risk of parietal complications. Compared to laparoscopic endosuture this procedure is simple, effective, easier, and particularly adapted to large ulcerated perforation or when an ulcer's edges are tough or friable, tending to tear when knots are tied.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Nashville, TN, USA, 18–19 April 1994. 相似文献
48.
李和泉 《中国病理生理杂志》1986,(2)
用反射光谱法,研究了组胺H_2受体阻断剂Famotidine对急性失血大鼠胃粘膜血液量及血氧饱和度的影响。同时观察了胃液量和酸排出量的变化,并计量了溃疡指数。Famotidine(3mg/kg及8mg/kg,iv)对失血前大鼠胃粘膜血液量和血氧饱和度均未见有影响;对失血后胃粘膜血液量和血氧饱和度的降低有明显保护作用,对胃液量和酸排出量均有显著抑制作用,溃疡指数减小。 相似文献
49.
Atypical gastric carcinoids 总被引:1,自引:0,他引:1
Four examples of infiltrating gastric tumours which had light microscopic features suggestive of carcinoid or oat-cell carcinoma are documented. Histological and ultrastructural findings indicated that these tumours were atypical carcinoids. A spectrum of endocrine cell neoplasia in the stomach analagous to that observed in the bronchus is postulated. It is felt that increased recognition of poorly differentiated endocrine tumours of the stomach might be of prognostic and therapeutic importance. 相似文献