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221.
OBJECTIVE: The role of routine endoscopic duodenal biopsies obtained during the evaluation of iron deficiency anaemia is being increasingly emphasized, but insufficiently applied. Diagnostic yield of this practice, mainly identification of coeliac disease, differs in different populations and geographic regions. The aim of this study is to assess the usefulness of routine duodenal biopsies during upper endoscopy in patients presenting with iron deficiency anaemia in Western Anatolia. METHODS: Routine duodenal biopsies were evaluated over a 12-month period in 100 consecutive adult patients with iron deficiency anaemia undergoing upper endoscopy. All potential bleeding lesions were identified and gastric as well as duodenal biopsies were taken for histopathologic investigation. RESULTS: A bleeding lesion is identified in 44% of cases. Duodenal biopsy gives an additional 5% diagnostic yield and revealed three patients with coeliac disease and two patients with giardiasis. One of the patients diagnosed with coeliac disease had a second bleeding lesion at the upper endoscopic examination. Appearance of the duodenal mucosa was normal in all patients including those with diagnostic duodenal biopsy. CONCLUSIONS: Routine duodenal sampling during the upper endoscopic examination gives an additional 5% diagnostic benefit and this practice should be included in the diagnostic work-up of patients with iron deficiency anaemia. As one of the patients who was found to have coeliac disease had a second bleeding lesion that may otherwise explain iron deficiency anaemia, finding a source for bleeding at the upper endoscopy should not preclude duodenal biopsy. Moreover, performing duodenal biopsy is still necessary even though the endoscopic appearance of the mucosa is normal. Aside from coeliac disease, Giardia infestation could be identified as a contributory factor for iron deficiency anaemia, in endemic regions.  相似文献   
222.
BACKGROUND: Although atherosclerosis is supposed to be responsible for more than 50% of coronary artery ectasia, the precise pathology of coronary artery ectasia is not clearly understood. A histopathological examination of ectatic segments has revealed mainly destruction of the media layer of the artery. In the present study, we assessed carotid intima-media thickness and common carotid artery diameter in patients with and without coronary artery ectasia. MATERIALS AND METHODS: Thirty-five consecutive patients with coronary artery ectasia and coronary artery disease and 35 age and sex-matched patients with coronary artery disease alone were included in the study. The common carotid artery was studied as the longitudinal plane within 10 mm from the bifurcation of the common carotid artery. The intima-media thickness was measured in the far wall at end-diastole from the B-mode screen to a point within the 10-mm segment proximal to the bifurcation by one investigator blinded to clinical data. RESULTS: No significant differences with respect to age, body mass index, hypertension, diabetes mellitus, hypercholesterolemia and smoking habits were observed between the two groups studied. Intima-media thickness of the common carotid artery of the patients with coronary artery ectasia was significantly lower than that of the patients with coronary artery disease alone (0.71 +/- 0.13 vs. 0.77 +/- 0.09 mm, respectively, P = 0.04). CONCLUSION: Decreased intima-media thickness of the carotid artery in patients with coronary artery ectasia and coronary artery disease may have pathogenic mechanisms different from coronary artery disease per se.  相似文献   
223.
Background: Oxidative stress has been associated with tissue injury in alcoholic liver disease. Although this close association is well known, whether prevention of oxidative stress retards tissue injury has not been thoroughly investigated.Objective: The aim of this study was to determine the effects of supplementation with vitamins E and C on antioxidant enzyme status and histologic changes in hepatic tissue in a rat model of alcoholic liver disease.Methods: This 8-week, blinded, controlled study was conducted at the Department of Internal Medicine, Trakya University, Edirne, Turkey. Weanling albino female protein-deficient Wistar rats weighing ∼200 g were randomly assigned to 1 of 6 groups: (1) liquid diet+ethanol+vitamin E 15 mg/kg PO (LDetvitE); (2) liquid diet+ethanol+vitamin C 10 mg/kg PO (LDetvitC); (3) liquid diet+ethanol+vitamin E 15 mg/kg+vitamin C 10 mg/kg PO (LDetvitEC); (4) liquid diet+ethanol (LDet); (5) liquid diet+isocaloric sucrose (LDS); and (6) normal diet (control). The primary end point of the study was to determine whether antioxidant vitamin E/C combination therapy prevents development of hepatic fibrosis (ie, cirrhosis in a period of 1 year). After being euthanized at week 8, the rats were weighed, and their livers and spleens were weighed. Hepatic tissue specimens were histopathologically assessed according to the Brunt system. Hepatic tissue glutathione peroxidase, superoxide dismutase, and catalase activities were determined. Biochemical tissue collagen concentrations were measured to determine the presence of hepatic fibrosis.Results: Seventy-two rats were included in the study (mean [SE] weight, 205 [21] g) (12 rats per group). Initially planned to last 48 weeks, the study was terminated at 8 weeks due to the death of 3 rats in each group (except the LDS group and control group). The relative liver weight was significantly lower in the LDetvitEC group compared with that in the LDet group (mean [SE], 3.7% [0.5%] vs 4.8% [0.9%]; P<0.01). Mean (SE) hepatic tissue glutathione peroxidase activity was significantly reduced in the LDet-treated rats compared with controls (1.2 [0.2] vs 2.6 [0.3] U/mg protein; P<0.001). The groups that received supplementation with vitamin E, vitamin C, and vitamins E and C combined had significantly more hepatic glutathione peroxidase activity (mean [SE], 2.1 [0.5], 2.5 [0.2], and 2.6 [0.7] U/mg protein, respectively) compared with the LDet group (1.2 [0.2] U/mg protein) (all, P<0.001). No significant between-group differences in hepatic superoxide dismutase or catalase activities were found. Compared with controls (14.5 [1.9] μg collagen/mg protein), the mean (SE) histologic hepatic collagen concentration was significantly higher in all groups (19.2 [1.2], 19.5 [3.3], 18.5 [3.0], 25.9 [3.3], and 21.6 [1.5] μg collagen/mg protein in the LDetvitE, LDetvitC, LDetvitEC, LDet, and LDS groups, respectively; P<0.01, P<0.01, P<0.05, P<0.001, and P<0.001, respectively). Compared with the LDet group, the mean hepatic collagen concentration was significantly lower in the LDetvitE, LDetvitC, and LDetvitEC groups (P<0.01, P<0.05, and P<0.01, respectively). The LDetvitEC group had a significantly lower mean (SE) hepatic inflammatory score compared with the LDet group (0.8 [0.1] vs 1.3 [0.2]; P<0.05). The LDetvitEC group had a significantly lower mean (SE) hepatic necrosis score compared with that in the LDet group (1.5 [0.2] vs 2.4 [0.3]; P<0.05).Conclusions: The results of this study in protein-deficient rats fed with a high-fat liquid diet suggest that supplementation with vitamin E, vitamin C, and a combination of vitamins E and C was associated with decreased ethanol-induced hepatic glutathione peroxidase activity and hepatic fibrosis, and that supplementation with vitamins E and C might have attenuated the development of hepatomegaly and hepatic necroinflammation, whereas this result was not found in the group given a liquid diet and ethanol in this 8-week study. (Curr Ther Res Clin Exp. 2006;67:118-137) Copyright © 2006 Excerpta Medica, Inc.  相似文献   
224.
OBJECTIVE: Chronic peritoneal dialysis (PD) may eventually result in vascular alterations of varying degree, which lead to progressive reduction in dialytic efficacy. Although the pathogenesis has not been elucidated yet, vascular endothelial growth factor (VEGF) has been proposed to play a central role in the process leading to vascular alterations. DESIGN: Rats were allocated to three groups: no treatment, intraperitoneal introduction of hypertonic PD solution alone, and intraperitoneal introduction of hypertonic PD solution plus octreotide. After 4 weeks, a 1-hour peritoneal equilibration test (PET) was performed. Dialysate-to-plasma urea ratio (D/P urea), glucose reabsorption (D1/D0 glucose), ultrafiltration volume (UF), and levels of dialysate protein and VEGF were determined. Peritoneal membrane histology was evaluated by light microscopy. RESULTS: Compared with the control group, rats treated with hypertonic PD solution showed dramatically deranged peritoneal function tests (UF: 5.8 +/- 0.9 mL vs 1.3 +/- 0.6 mL; D/P urea: 0.49 +/- 0.1 vs 0.74 +/- 0.04; D1/D0 glucose: 0.55 +/- 0.05 vs 0.34 +/- 0.06) and morphology (thickness: 4.6 +/- 0.4 mu vs 62 +/- 12 mu; neovascularisation: 0.1 +/- 0.3 vessels per field vs 2.2 +/- 0.3 vessels per field). Similarly, a higher level of VEGF was found in the rats treated with hypertonic PD solution. In rats treated with hypertonic solution plus octreotide, peritoneal thickness was not completely reduced (25 +/- 5 mu), but peritoneal functions were protected (UF: 4.0 +/- 0.5 mL; D/P urea: 0.58 +/- 0.02; D1/D0 glucose: 0.51 +/- 0.02). Moreover, VEGF level and neoangiogenesis were significantly less in the octreotide group than in the group treated with hypertonic dextrose alone. CONCLUSION: Our data document that, by increasing the production of VEGF, a high glucose concentration can cause vascular alterations within the peritoneal membrane. Octreotide can protect against the vascular alterations and preserve peritoneal function by inhibiting overexpression of VEGF and regulating the inflammatory response in the peritoneum.  相似文献   
225.
The EUROMET project 428 examines efficiency transfer results for Ge gamma-ray spectrometers when the efficiency is known for a reference point source geometry. For this, different methods are used, such as Monte Carlo simulation or semi-empirical computation. The exercise compares the application of these methods to the same selected experimental cases to determine the usage limitations versus the requested accuracy. For carefully examining these results and trying to derive information for improving the computation codes, this study was limited to a few simple cases. The first part concerns the simplest case of geometry transfer, i.e., using point sources for 3 source-to-detector distances: 2, 5 and 20 cm; the second part deals with transfer from point source geometry to cylindrical geometry with three different matrices. The general conclusion is that the deviations between the computed results and the measured efficiencies are mostly within 10%. The quality of the results is rather inhomogeneous and shows that these codes cannot be used directly for metrological purposes. However, most of them are operational for routine measurements when efficiency uncertainties of 5-10% can be sufficient.  相似文献   
226.
AIM: On the suspected carpal instabilities stress views are recommended but not often used. The present study evaluates the reliability of the dorsal and volar stress radiographs on patients with posttraumatic wrist pain. PATIENTS AND METHODS: Stress radiographs of the wrists were examined in 22 patients with chronic wrist pain and the results were compared with scaphoid shift test and standard and positional views. The stress examination consists of applying to the wrist dorsal and volar stresses on the hand. RESULTS: Static scapholunate instability was diagnosed in 4 patients in whom 3 of them had positive scaphoid shift test sign as well. There were, however, 18 patients with dynamic scapholunate instability in whom the standard films were normal but dorsal stress radiography showed gap greater than 3mm between the scaphoid and lunate. CONCLUSION: Stress tests may provide considerable information in the evaluation of a patient who has a painful wrist in whom routine and special views do not demonstrate scapholunate dissociation.  相似文献   
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