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151.
J Svanvik C A Pellegrini B Allen R Bernhoft L W Way 《The Journal of surgical research》1986,41(4):425-431
In acute cholecystitis the cystic duct is usually obstructed by a gallstone and the gallbladder is often tensely distended with clear fluid. Because these findings suggest that fluid absorption in the gallbladder may be reversed in cholecystitis, we examined the effect of inflammation on the gallbladder mucosal function in dogs. In 20 dogs cholecystitis was induced by ligating the cystic duct and allowing inflammation to develop from bile stasis and the presence of a chronic indwelling cannula in the gallbladder. Every morning an aliquot of normal hepatic bile was infused into the gallbladder through a cannula in the gallbladder fundus. After either 4 or 24 hr the gallbladder contents were aspirated, the volume was measured, and the concentrations of bile acids, cholesterol, phospholipids, and protein were determined. Changes in volume were checked using [14C]PEG as a nonabsorbable tracer. A net absorption of fluid, bile acids, cholesterol, and phospholipids occurred during the first 24 to 48 hr after ligation of the cystic duct. Thereafter, fluid, cholesterol, and protein were secreted into the lumen, but absorption of bile acids continued. The lithogenic index of bile placed in the inflamed gallbladder was always greater when the bile was removed 24 hr later. The rate of fluid secretion into the lumen of the inflamed gallbladder increased after a meal and decreased after indomethacin. These findings demonstrate that inflammation can stimulate the gallbladder mucosa to secrete fluid, a process that may be important in the pathophysiology of acute cholecystitis in man. Since inflammation also resulted in an increased cholesterol saturation of gallbladder bile, cholecystitis per se may contribute to the formation of cholesterol gallstones. 相似文献
152.
C A Pellegrini C W Deveney M G Patti M Lewin L W Way 《American journal of surgery》1986,151(1):117-125
We examined small bowel transit of solid food in 10 patients 3 to 30 months after total gastrectomy and Roux-Y esophagojejunostomy and compared the transit pattern with that in five control subjects. All persons ate a test meal consisting of 213 g of beef stew mixed with 30 g of chicken liver which was labeled with 1 mCi of technetium 99m sulfur colloid, and they stood in front of a gamma scintillation camera and were studied for 6 to 10 hours. Solid food passed rapidly from the esophagus through the Roux-Y limb and became uniformly distributed throughout a long segment of the small intestine. Mouth-to-colon transit time was 223 +/- 18 minutes in the control subjects and 298 +/- 37 minutes in the patients with gastrectomy. Small bowel transit of the head of the meal was 187 +/- 19 minutes in the control subjects and 293 +/- 37 minutes in the patients (p less than 0.02). Transit time of the tail of the meal was 175 +/- 26 minutes in the control subjects and 396 +/- 28 minutes in the patients (p less than 0.001). After total gastrectomy and Roux-Y esophagojejunostomy, the proximal jejunum does not act as a reservoir; transit of food through the small intestine is slower than in control subjects, and because the proximal jejunum empties rapidly during eating, a meal of normal size can be consumed. These findings do not support the idea that an artificial gastric reservoir is important after total gastrectomy. 相似文献
153.
Twenty patients, aged 4 months to 58 years, were evaluated for liver transplantation by duplex sonography, and 15 transplantations were completed; 42 postoperative examinations were performed. Sonographic findings were correlated with seven preoperative and five postoperative angiographic evaluations. Preoperative duplex US findings included tumors, portal vein occlusion, varices, biliary obstruction, and variant vascular anatomy. Postoperative findings included hepatic artery occlusion, portal vein occlusions (one with cavernous transformation), portal vein stenosis, biliary obstruction, intrahepatic and extrahepatic fluid collections, and air in the portal vein due to ischemic bowel. Use of angiography allowed confirmation of the vascular abnormalities and demonstrated evidence of rejection in patients with normal Doppler waveforms. Duplex sonography is a valuable portable technique for evaluating these patients and can be used in triage of patients requiring angiography. 相似文献
154.
Gastric emptying and small bowel transit of solid food after pylorus-preserving pancreaticoduodenectomy 总被引:5,自引:0,他引:5
We examined the gastric emptying and small bowel transit of solid food in ten patients one to 45 months after pylorus-preserving pancreaticoduodenectomy. Gastric emptying and small bowel transit were measured by computer analysis of data from a scintillation camera using technetium Tc 99m-tagged chicken liver mixed with beef stew and were compared with the results in five control subjects. The nutritional status of the patients was also evaluated. Gastric emptying was normal in six patients, rapid in three patients, and delayed in one patient. Small bowel transit was normal in two patients, rapid in seven patients, and delayed in one patient. Most of the patients were asymptomatic, ate three meals a day, and gained weight after the operation. These findings show that after pylorus-preserving pancreaticoduodenectomy, most patients consume a regular diet and achieve an excellent nutritional status. Gastric emptying is normal, not slowed. Small bowel transit is faster than normal but is without clinical sequelae. 相似文献
155.
Lymphatic vascular endothelium both on tissue section and in culture exhibits positivity for Factor VIII-associated antigen although staining is generally less intense and more spotty than in comparable blood vascular endothelium. Lymphatic endothelium also exhibits Weibel-Palade bodies. Neither marker, therefore, reliably distinguishes blood vascular endothelium from lymphatic endothelium. 相似文献
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157.
2-[对-(二甲氨基)苯乙烯]氯化甲基吡啶(DSPM-Cl),是由氯取代2-[对-(二甲氨基)苯乙烯]碘化甲基吡啶(DSPM)上的碘而得。本文应用心电图、机械收缩描记方法及细胞内标准微电极技术,研究DSPM-Cl对大鼠心电图(ECG)、豚鼠心房肌量效曲线及对豚鼠乳头肌快反应动作电位(AP)、高钾除极慢反应动作电位(SAP)的影响。结果显示,DSPM-Cl(2mg·kg-1)对大鼠有明显的负性频率、负性传导作用,分别使PP间期、PR间期延长达66.2%(P<0.01),17.0%(P<0.01),50μmol·L-1能明显抑制左心房收缩力,非竟争性拮抗Iso及CaCl2对豚鼠左心房的正性肌力作用,PD2'分别为4.6,4.34,100μmol·L-1DSPM-Cl延长动作电位时程APD90,有效不应期(ERP),降低高钾除极豚鼠乳头肌0期最大上升速率Vmax,其作用与Ver相似,提示DSPM-Cl可能为钙拮抗剂。 相似文献
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