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Scoring manual for the Thought Disorder Index 总被引:1,自引:0,他引:1
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G T Mogavero B Jones J L Cameron J Coleman 《AJR. American journal of roentgenology》1992,159(5):1001-1003
OBJECTIVE. Our objective was to study the imaging findings in patients who had gastric and duodenal obstruction as a long-term complication of cholangiocarcinoma and to determine if the obstruction was associated with radiation therapy. MATERIALS AND METHODS. Between 1973 and 1989, 96 patients had either curative resection or palliative stenting for cholangiocarcinoma involving the hepatic duct bifurcation. Sixty-three (66%) also received adjuvant radiation therapy ranging from 4960 to 7220 rad (cGy). Gastric outlet or duodenal obstruction or both developed subsequently in seven of the 63 patients treated with radiation therapy. Radiographic studies, including upper gastrointestinal series and CT, and medical and surgical records for these seven patients were retrospectively reviewed. RESULTS. Upper gastrointestinal series in the seven patients with obstruction showed narrowing of the lumen, deformity and enlargement of gastric and duodenal mucosal folds, and delayed gastric emptying. CT performed in five of the seven patients showed thickening of the wall of the gastric antrum and small bowel and retained food and fluid within the stomach. All seven patients required gastrojejunostomy; at surgery, dense adhesions and fibrosis were found, and it was not evident whether the obstruction was due to the tumor or to radiation fibrosis. However, because this complication was seen only after radiotherapy, it was presumed to be radiation fibrosis. CONCLUSION. Our experience suggests that radiation therapy increases the risk of postoperative gastric and duodenal obstruction in patients undergoing surgery for cholangiocarcinoma. 相似文献
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Fat absorption in premature infants: medium-chain triglycerides and long-chain triglycerides are absorbed from formula at similar rates 总被引:1,自引:0,他引:1
M Hamosh N R Mehta C S Fink J Coleman P Hamosh 《Journal of pediatric gastroenterology and nutrition》1991,13(2):143-149
Fat absorption from two different premature infant formulas and one full-term formula containing three different fat blends was investigated in two groups of premature infants. The first group of nine infants (gestational age, 29.1 +/- 0.88 weeks; postnatal age, 3.13 +/- 0.71 weeks) was fed alternately for 1 week each SMA preterm formula containing either high levels (50%) of medium-chain triglycerides (MCT) (6:0, 8:0, and 10:0) or high levels (86%) of long-chain triglycerides (LCT) (greater than or equal to C12). Except for fat blends, the formulas were otherwise identical. The second group of 11 infants (gestational age, 30.5 +/- 0.77 weeks, studied at a postnatal age of 4.33 +/- 0.91 weeks) was fed for 1 week a full-term infant formula, S-26, containing 98% LCT. Fat absorption (studied during a 3-day fat balance period) was similar irrespective of fat blend: 89.08 +/- 2.37% during feeding of preterm SMA, 50% MCT; 87.0 +/- 3.81% during feeding of preterm SMA, 86% LCT; and 83.00 +/- 2.89% during feeding of S-26, 98% LCT. Weight gain (grams per day) and increase in length (centimeters per day) were 23.2 +/- 1.7, 21.20 +/- 1.7, and 14.28 +/- 2.9, and 0.17 +/- 0.06, 0.16 +/- 0.04, and 0.22 +/- 0.07 during feeding of the three fat blends, respectively. Lipase activity levels in fasting gastric aspirates were higher during feeding of the LCT than the MCT formula. The possible stimulation of gastric lipase secretion secondary to long-chain fatty acid stimulation of cholecystokinin secretion might be related to the efficient digestion of formula fat, irrespective of triglyceride-fatty acid chain length.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Laurie M. Lomasney John F. Madden Wagdy S. Rizk Lawrence W. Hedlund Salutorio Martinez Robert E. Coleman William J. Richardson H. Dirk Sostman 《Journal of magnetic resonance imaging : JMRI》1994,4(3):441-449
Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise. 相似文献
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G Bradley T J Ward J C White J Coleman A Taylor K F Rhodes 《Journal of medicinal chemistry》1992,35(9):1515-1520
A series of benzoylureas derived from bicycle amines were prepared and evaluated for 5-HT3 antagonist activity on the rat isolated vagus nerve. From among these compounds, those analogues which were ortho substituted by an alkoxy group on the benzoyl function were shown to be potent 5-HT3 antagonists with similar or greater potency than the standard agent ondansetron. NMR and X-ray crystallography studies showed these o-alkoxy compounds to exist as a planar, hydrogen-bonded, tricyclic ring system. In molecular modeling studies on endo-N-[[(8-methyl-8-azabicyclo[3.2.1]octan-3-yl-amino] carbonyl]-2-(cyclopropylmethoxy)benzamide (30) the central hydrogen-bonded ring was able to mimic an aromatic ring present in previously reported 5-HT3 antagonists. 相似文献
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Inhibition of dapsone-induced methaemoglobinaemia in the rat isolated perfused liver 总被引:1,自引:0,他引:1
M D Coleman P E Hoaksey A M Breckenridge B K Park 《The Journal of pharmacy and pharmacology》1990,42(5):302-307
We have investigated the disposition of dapsone (DDS, 1 mg) in the rat isolated perfused liver in the absence and the presence of cimetidine (3 mg). After the addition of DDS alone to the liver there was a monoexponential decline of parent drug concentrations and rapid formation of DDS-NOH (within 10 min) which coincided with methaemoglobin formation (11.7 +/- 3.0%, mean +/- s.d.) which reached a maximum (22.6 +/- 9.2%) at 1 h. The appearance of monoacetyl DDS (MADDS) was not apparent until 30-45 min. Addition of cimetidine resulted in major changes in the pharmacokinetics of DDS and its metabolites. The AUC of DDS in the presence of cimetidine (1018.8 +/- 267.8 micrograms min mL-1) was almost three-fold higher than control (345.0 +/- 68.1 micrograms min mL-1, P less than 0.01). The half-life of DDS was also prolonged by cimetidine compared with control (117.0 +/- 48.2 min vs 51.2 +/- 22.9, P less than 0.05). The clearance of DDS (3.0 +/- 0.55 mL min-1) was greatly reduced in the presence of cimetidine (1.03 +/- 0.26 mL min-1 P less than 0.01). The AUC0-3h for DDS-NOH (28.3 +/- 21.2 micrograms min mL-1) was significantly reduced by cimetidine (8.1 +/- 3.40 micrograms min mL-1, P less than 0.01). In contrast, there was a marked increase in the AUC0-3h for MADDS (32.7 +/- 25.8 micrograms min mL-1) in the presence of cimetidine (166.0 +/- 26.5 micrograms min mL-1 P less than 0.01). The methaemoglobinaemia associated with DDS was reduced to below 5% by cimetidine. Hence, a shift in hepatic metabolism from bioactivation (N-hydroxylation) to detoxication (N-acetylation) caused by cimetidine, was associated with a fall in methaemoglobinaemia. These data suggest that the combination of DDS with a cytochrome P450 inhibitor might reduce the risk to benefit ratio of DDS. 相似文献