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111.
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Small (1.5 cm or less) liver metastases: US-guided biopsy 总被引:2,自引:0,他引:2
113.
Modulation of liver tumor blood flow with hepatic arterial epinephrine: a SPECT study 总被引:3,自引:0,他引:3
Changes in the relative arterial flow to hepatic tumors and adjacent normal liver, in response to varied doses of hepatic arterial epinephrine, were studied with single photon emission computed tomography. In 18 patients with known hepatic tumors, hepatic artery perfusion scans were obtained with the concurrent infusion of technetium-99m-labeled macroaggregated albumin and escalating doses of epinephrine (0-10 micrograms/min). Regions of interest were drawn around tumor and adjacent normal liver in three planes, and the average tumor-to-liver ratio (T:L) was calculated. In all 18 patients, there was a measurable baseline T:L perfusion advantage (range, 1.7-18.7; mean, 4.8). In 12 of 18 patients, this ratio increased with epinephrine (range, 1.1-53.6 times the baseline value; mean, 7.1). In six patients, no improvement in T:L could be demonstrated. In 14 patients the lung shunt index, a measurement of arteriovenous shunting, increased with escalating doses of epinephrine. This pilot study suggests that the infusion of epinephrine may improve the therapeutic index of certain regional therapies such as bolus drug infusions, hepatic arterial embolization, and radioactive microsphere therapy. 相似文献
114.
To determine the effect of a fraction of licorice extract, FM100, on the endogenous release of secretin and exocrine pancreatic secretion, five dogs were prepared with chronic pancreatic fistulas and gastric cannulas. Intraduodenal administration of licorice extract (pH 7.4) in three different doses (0.5, 1.0, and 2.0 g) resulted in significant increases of both plasma secretin concentrations and pancreatic bicarbonate secretion in a dose-related manner. The plasma secretin concentration and pancreatic bicarbonate output produced by licorice extract correlated well. Intragastric administration of licorice extract (2 g) in 5% liver extract meal (in which pH was maintained at 5.5 by the intragastric titration method) resulted in significant increases of both plasma secretin concentration and pancreatic bicarbonate output. The increase in pancreatic bicarbonate secretion was completely abolished by intravenous infusion of a rabbit antisecretin serum in the two dogs so studied. Thus, the present study indicates that the endogenous release of secretion is involved in a mechanism of an increase in exocrine pancreatic secretin induced by FM100. 相似文献
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Dr. Thomas V. Nowak MD William W. Chey MD Ta-Min Chang PhD John P. Weisbruch BS Gary Fouquet BS 《Digestive diseases and sciences》1995,40(4):828-836
Representative longitudinal muscle strips (6 × 10 mm) from proximal and distal small intestine were excised from control and streptozotocin-treated rats after one month of untreated and insulin-treated diabetes. Untreated diabetes significantly reduced tissue concentrations of vasoactive intestinal polypeptide (VIP) at both intestinal loci. Insulin treatment of the diabetic animals restored tissue VIP concentrations to control group levels, although the beneficial effect of insulin treatment was only significant in the duodenum. Spontaneous release of VIP was significantly attenuated by untreated diabetes at both intestinal sites. In the duodenum, insulin treatment of the diabetic animals restored VIP release to levels indistinguishable from control group values. In the ileum, insulin treatment produced levels of VIP release that were not significantly different from those of the control and untreated diabetic groups. Tetrodotoxin (5 × 10?6 M) significantly—but incompletely—inhibited VIP release from control group animals at both intestinal sites. These observations indicate that diabetes mellitus significantly diminishes VIP tissue concentrations and release from intestinal myenteric nerves. These abnormalities improve with insulin treatment. However, the mechanisms of VIP release from proximal and distal intestine appear to differ not only in their response to the diabetic state, but also in their response to insulin treatment. 相似文献
120.
Enterohepatic circulation is essential for regular cycling of duodenal migrating motor complexes in dogs. 总被引:6,自引:0,他引:6
The role of enterohepatic circulation and specific bile acids in the initiation and caudad migration of duodenal migrating motor complexes (MMCs) was investigated in conscious dogs. All dogs had spontaneous duodenal MMCs that migrated to the terminal ileum when bile flow was intact. During the first 3 days after total external biliary diversion, no MMCs originated in the duodenum. Instead, all MMCs originated in the jejunum and migrated to the ileum. During the next 4 days of total external biliary diversion, 81% of the MMCs originated in the jejunum and 19% in the duodenum. When normal bile flow was restored after 9 days of total external biliary diversion, regular duodenal MMCs resumed after a delay of 126 +/- 27 minutes. Perfusion of individual bile acids or dogs' own bile, but not saline or alkaline solution, into the duodenum or perfusion of dogs' own bile directly into the ileum during total external biliary diversion restarted duodenal MMCs with a time lag of about 2 hours. The authors conclude that intact enterohepatic circulation is essential for the initiation of regular duodenal MMCs. 相似文献