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941.
CT findings in patients with esophagitis 总被引:4,自引:0,他引:4
OBJECTIVE: The purpose of our study was to determine the CT findings in patients with esophagitis. MATERIALS AND METHODS: A search of medical and radiology files revealed 29 patients with esophagitis in whom thoracic CT was performed within 1 month of the diagnosis. The CT scans were reviewed retrospectively for esophageal wall thickening, a target sign, or other abnormalities. The thickness of the esophageal wall was also measured on CT in these 29 patients and compared with a control group of 85 patients. RESULTS: We found that 16 patients (55%) with esophagitis had abnormal findings on CT, including a thickened esophageal wall (using 5 mm as the threshold for wall thickening) in all 16 (55%) and a target sign in five (17%). The overall mean esophageal wall thickness was 4.7 mm (standard deviation [SD], 2 mm; 95% confidence interval [CI], 0.7-8.7 mm) in patients with esophagitis versus a mean wall thickness of 2.9 mm (SD, 0.8 mm; 95% CI, 1.3-4.5 mm) in controls (p <.001). Using the same 5-mm threshold for wall thickening, we found that only three (4%) of 85 controls had a thickened esophageal wall on CT. CONCLUSION: The majority of patients with esophagitis had abnormalities on CT, including a thickened esophageal wall (> or =5 mm) in 55% and a target sign in 17%. Although barium studies and endoscopy are more sensitive modalities for detecting this condition, the CT finding of a relatively long segment of circumferential esophageal wall thickening, with or without a target sign, should suggest the diagnosis of esophagitis in the proper clinical setting. 相似文献
942.
Shelley Brown DuTeaux John W Newman Christophe Morisseau Elise A Fairbairn Karen Jelks Bruce D Hammock Marion G Miller 《Toxicological sciences》2004,78(2):187-195
Epoxide hydrolases play an important role in detoxifying epoxides that arise from the metabolism of xenobiotic and endogenous compounds. Both the soluble and microsomal forms of epoxide hydrolase (sEH and mEH, respectively) have been detected in the rat testis. Because of the important role the epididymis plays in sperm maturation and protection, the present study evaluated the presence and activity of these two epoxide hydrolases in the rat epididymis. Using Western blotting, protein bands consistent in size with both mEH and sEH were detected in the caput, corpus, and cauda of the epididymis. The mEH immunoreactive bands in the epididymis ( approximately 50 kDa) were consistent with mEH detected in the liver and kidney. The sEH immunoreactive bands in the epididymis ( approximately 65 kDa) were consistent with a recombinant sEH standard and sEH detected in the liver, kidney, and testis. The presence of mEH and sEH in the epididymis was supported by observations from substrate-based enzyme assays. Results indicated that epididymal mEH can hydrolyze [(3)H]-cis-stilbene oxide to the corresponding diol at levels approximately 9% of the kidney. Epididymal sEH hydrolyzed the substrate [(3)H]-trans-diphenylpropene oxide to the corresponding diol and this activity was inhibited by cyclohexyl-dodecyl urea. Arachidonic acid epoxygenase activity was detected in epididymal S9 fractions, suggesting that fatty acid metabolism by epididymal cytochrome P450s can form epoxides that subsequently become substrates for epididymal sEH. Results from the present study indicate that the epididymis contains at least two active forms of epoxide hydrolase. The role of these enzymes in the detoxification of xenobiotic epoxides is well known, although it is unclear what cellular role they may play in the formation of biologically active metabolites in the epididymis. 相似文献
943.
BACKGROUND: The pathogenesis of generalized microvascular injury after hemorrhagic shock is known to involve the generation of platelet-activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine [PAF]). The release of PAF is manifested in several ways, including by increased vascular permeability, altered vascular reactivity, and increased leukocyte adherence to the endothelium. WEB 2086 is a PAF antagonist that has been shown experimentally to improve survival after hemorrhagic shock. The purpose of this study was to examine the efficacy of WEB 2086 in attenuating leukocyte adherence before, during, and after hemorrhagic shock. METHODS: After a control period, blood was withdrawn to reduce the mean arterial pressure to 40 mm Hg for 30 minutes in urethane-anesthetized rats. Mesenteric venules in a transilluminated segment of the small bowel were examined to quantitate leukocyte adherence using intravital microscopy. RESULTS: In sham-operated rats (control), there was minimal to no leukocyte adherence throughout the experiment. Hemorrhagic shock resulted in a significant increase in leukocyte adherence postshock during resuscitation (10.9 +/- 1.8 cells/100 microm, p < 0.01) when compared with controls. WEB 2086, when given before shock, significantly attenuated leukocyte adherence (0.1 +/- 0.08 cells/100 microm, p < 0.01) when compared with hemorrhagic shock alone. This effect of WEB 2086 on adherence could be demonstrated even when it was given during (3.5 +/- 0.9 cells/100 microm, p < 0.01) and 10 minutes into (5.8 +/- 1.1 cells/100 microm, p < 0.05) hemorrhagic shock. CONCLUSION: Our findings suggest that WEB 2086 may be of therapeutic benefit against the microvascular damage sustained after hemorrhagic shock. 相似文献
944.
945.
Matthew. B. Miller Julienne Brackett Eric S. Schafer Rachel E. Rau 《Pediatric blood & cancer》2019,66(4)
Skewing of mercaptopurine (6‐MP) metabolism preferentially toward the 6‐methylmercaptopurine (6‐MMP) metabolite over the antileukemic metabolite 6‐thioguanine (6‐TGN) is associated with 6‐MP‐related hepatotoxocity. Allopurinol when coadministered with 6‐MP can reduce this skewing and ameliorate the associated adverse effects. The cases we report here demonstrate that aberrant overproduction of 6‐MMP is also associated with profound 6‐MP‐associated hypoglycemia, which can be reversed by administration of allopurinol. This case series contributes to the scant literature on 6‐MP‐induced hypoglycemia and provides evidence that addition of allopurinol to reduced dose 6‐MP can successfully manage this severe toxicity. 相似文献
946.
947.
D.P. Beavers K.M. Beavers M. Miller J. Stamey M.J. Messina 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2012,22(3):182-191
Background and AimsTo determine whether and to what degree exposure to isoflavone-containing soy products affects EF. Endothelial dysfunction has been identified as an independent coronary heart disease risk factor and a strong predictor of long-term cardiovascular morbidity and mortality. Data on the effects of exposure to isoflavone-containing soy products on EF are conflicting.Methods and ResultsA comprehensive literature search was conducted using the PUBMED database (National Library of Medicine, Bethesda, MD) inclusively through August 21, 2009 on RCTs using the keywords: soy, isoflavone, phytoestrogen, EF, flow mediated vasodilation, and FMD. A Bayesian meta-analysis was conducted to provide a comprehensive account of the effect of isoflavone-containing soy products on EF, as measured by FMD. A total of 17 RCTs were selected as having sufficient data for study inclusion. The overall mean absolute change in FMD (95% Bayesian CI) for isoflavone-containing soy product interventions was 1.15% (?0.52, 2.75). When the effects of separate interventions were considered, the treatment effect for isolated isoflavones was 1.98% (0.07, 3.97) compared to 0.72% (?1.39, 2.90) for isoflavone-containing soy protein. The models were not improved when considering study-specific effects such as cuff measurement location, prescribed dietary modification, and impaired baseline FMD.ConclusionsCumulative evidence from the RCTs included in this meta-analysis indicates that exposure to soy isoflavones can modestly, but significantly, improve EF as measured by FMD. Therefore, exposure to isoflavone supplements may beneficially influence vascular health. 相似文献
948.
949.
Nancy Fagley Paul Miller Dr. John Sullivan Ph.D. 《Behavioral medicine (Washington, D.C.)》2013,39(2):15-22
Abstract Symptom proneness (SP), the 20 psychiatric items of the Cornell Medical Index, here called the Cornell Psychiatric Items (CPI), and a test developed partially from the Schedule of Recent Experiences called the Utah Stress Scales (STRESS) were used to predict general adaptational distress (GAD) symptoms during pregnancy on a sample of 1306 primigravidas. The causal model explored in seven path analyses developed for months 3–9 of pregnancy is that SP and STRESS affect CPI, and that SP, STRESS, and CPI directly affect GAD symptoms. Results suggest that CPI is most predictive of GAD symptoms until the ninth month when SP and STRESS become more predictive. It is suggested that GAD pregnancy symptoms are affected by situational stress, symptom proneness, and level of psychological upset and that this system of relations changes over the course of pregnancy. This information should have important implications for anticipating potential problems and improving the quality of nursing care of pregnant women. 相似文献
950.