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991.
GA Lazaros GB Dounis FC Panou VP Georgoulas AA Zacharoulis 《Canadian Metallurgical Quarterly》1998,39(5):659-662
BACKGROUND: Endoscopic diagnosis of short segments of Barrett's epithelium (SSBE)' is difficult and its meaning in terms of the presence of specialised columnar epithelium (SCE) has not been prospectively evaluated. AIMS: To evaluate the prevalence of SCE in patients with an endoscopic diagnosis of SSBE and in individuals with normal appearing oesophagogastric junctions, and to compare the clinical characteristics of these two groups. PATIENTS: Thirty one patients with an endoscopic diagnosis of short Barrett's oesophagus, less than 3 cm in length (group A), and 44 consecutive patients with normal appearing oesophagogastric junctions (group B). METHODS: Multiple biopsies were performed in suspicious epithelium and at the oesophagogastric junction in groups A and B, respectively. RESULTS: Age and sex distribution were similar in both groups. Reflux symptoms were more frequent in group A (p < 0.001), as were endoscopic and histological signs of oesophagitis (p < 0.001 and p = 0.001, respectively). SCE was found in 61.3% of group A patients compared with 25% in group B (p < 0.002), with men predominating in group A while women were more frequent in group B (p = 0.02). The differences in reflux symptoms and endoscopic/histological oesophagitis remained significant. CONCLUSIONS: These results show that endoscopic diagnosis of SSBE is associated with a high prevalence of SCE, significantly higher than that found in normal appearing oesophagogastric junctions. Differences between patients with SCE in the two groups suggest they may represent two different entities. 相似文献
992.
AA van den Berg 《Canadian Metallurgical Quarterly》1996,51(2):194-197
One hundred and sixty seven operating theatre personnel familiar with the practice of venous cannulation were asked to rank (in increasing order from one to five, corresponding to least to most painful) their opinion of the pain which they considered might accompany venous cannulation of each of five vein sites on the upper limb (dorsum of arm, dorsum of hand, cephalic, ventrum of arm and cubital fossa) which may be selected for this purpose. The skin sensitivity of each of the test sites of each volunteer was then assessed with a test device comprising a Tuohy needle and clamp, which together weighed 75.02 g. Following random application of the device to each of the test sites, the volunteer was asked to rank (in increasing order from one to five, corresponding to least to most painful) the actual pain felt. Analysis of pain expectations showed that there was no significant consensus view as to which site would be most tender. Following application of the test device the tenderness of the five sites was ranked (i) according to frequencies; dorsum of arm < dorsum of hand < cephalic < ventrum of arm < cubital fossa and, (ii) following statistical analysis: dorsum of arm = dorsum of hand = cephalic < ventrum of arm < cubital fossa. There was no correlation between expected and actual skin sensitivities. Knowledge of the different skin sensitivities of the upper limb may be useful when selecting a vein for venepuncture or the insertion of an indwelling venous catheter. 相似文献
993.
AA Lubberink 《Canadian Metallurgical Quarterly》1997,122(24):705-707
994.
995.
Cardiodepressive and arrhythmogenic properties of cordarone were studied on cat in conditions of experimental acute ischemia and myocardial infarction upon intravenous infusion. The obtained results showed an increase cordarone cardiotoxicity and arrhythmogenic properties in conditions of myocardial infarction. No reliable difference was observed in dynamics of cordarone-induced changes in ECG parameters in animals with myocardial ischemia of various duration and intact animals. 相似文献
996.
997.
PR Brakeman AA Lanahan R O'Brien K Roche CA Barnes RL Huganir PF Worley 《Canadian Metallurgical Quarterly》1997,386(6622):284-288
998.
Glucose-sensitive phase-reversible hydrogels have been prepared based on the specific interaction between polymer-bound glucose and concanavalin A (Con-A). The main goal of this study was to characterize the release of model proteins (insulin and lysozyme) through the hydrogel membrane as the free glucose concentration in the environment was changed. The diffusion of the model proteins through the hydrogel membrane was examined using a diffusion cell. Porous poly(hydroxyethyl methacrylate) (PHEMA) membranes were used to sandwich the mixture of glucose-containing polymers and Con-A in between the donor and receptor chambers. The porous PHEMA membranes allowed diffusion of glucose, insulin and lysozyme, while preventing loss of glucose-containing polymers and Con-A in the sol state. The release rate of model proteins through the glucose-sensitive hydrogel membrane was dependent on the concentration of free glucose. The release rate of the proteins did not remain constant, however, due to the change in free glucose concentration resulting from diffusion of glucose from the receptor chamber to the donor chamber. This study demonstrated the possibility that the glucose-sensitive phase-reversible hydrogels can be used to regulate the insulin release as a function of the free glucose concentration in the environment. 相似文献
999.
1000.
A nonsteroidal antiinflammatory drug, 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl) thiophene (BFMeT), induced ileal ulcers in rats after oral administration, while no ulcers were observed after subcutaneous injection. The ileal ulcer formation in BFMeT-treated rats was examined to correlate the administration of cultures of Lactobacillus acidophilus or Bifidobacterium adolescentis with intestinal bacteria in the ileal contents and lipid peroxidation of the small intestinal mucosa. Ileal ulcers were observed in more than 85% of the rats treated with BFMeT at a dose of 1,000 mg/kg when they were given tap water as drinking water. The incidence of ulcer formation was repressed by giving culture supernatants of L. acidophilus or B. adolescentis as drinking water, but not by giving the cell suspension as drinking water. Gram staining of the ileal contents of normal rats revealed that 97% of the stained bacteria were gram-positive rods and only 1.5% were gram-negative rods. The percentage of gram-negative rods 72 hr after BFMeT administration was 49.8% and increased over 30-fold in BFMeT-treated rats. However, the percentage of gram-negative rods was 9.7 % or 16%, respectively, in rats taking culture supernatants of L acidophilus or B. adolescentis. In addition, thiobarbituric acid-reactive substances in the ileal mucosa increased significantly in the rats given tap water for 72 hr after BFMeT treatment, but not in rats given the culture supernatants of L. acidophilus or B. adolescentis. Since BFMeT induced an unbalanced intestinal microflora, the effect of antibiotic treatment on ulcer formation in rats was examined. The magnitude of the ulcer formation in the antibiotic-treated rats was, in decreasing order, metronidazole >none > kanamycin > a mixture (bacitracin, neomycin and streptomycin). These results suggest that the intestinal microflora plays an important role in ulcer formation and that a metabolite(s) of L. acidophilus and B. adolescentis inhibits ileal ulcer formation by repressing changes in the intestinal microflora and lipid peroxidation in BFMeT-treated rats. 相似文献