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181.
Whipple''s disease is a rare multi-organ infectious disease caused by Tropheryma whipplei. It is fatal without treatment. We report on a 40-year old Afro-Jamaican man who presented with a six-month history of weight loss and diarrhoea. Investigations revealed iron deficiency anaemia and hypoalbu-minaemia. Upper gastrointestinal endoscopy revealed white patchy lesions in the duodenum. The duodenal biopsy showed broadening and thickening of the villi by a dense infiltrate of foamy histiocytes within the lamina propria and focally extending into the attached submucosa. Periodic Acid-Schiff stains were positive. Electron microscopy was confirmatory and polymerase chain reaction testing conclusively identified the organisms as T whipplei. Antibiotic treatment resulted in resolution of symptoms. Although the diagnosis of Whipple''s disease is difficult, increased awareness should lead to an increase in reported cases with the improvements in diagnostic capabilities.  相似文献   
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We describe an adapted first-transit (FT) technique to perform left ventricular ejection fraction (LVEF) measurements on patients with Swan-Ganz catheters in the intensive cardiac care unit (ICCU). The radionuclide is introduced directly into the right pulmonary artery through the catheter. High-quality images of the left ventricle are obtained owing to minimal activity in the right ventricle and left lung. LVEF measurements obtained by FT compared well with measurements obtained from gated blood pool studies (r = 0.91) but gave consistently lower values. The adapted FT method improves LVEF determination and left-ventricular wall motion evaluation in the ICCU patient.  相似文献   
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Anaemia is a common feature of rheumatoid arthritis (RA) and other chronic diseases. Among the alterations in iron metabolism contributing to this effect is a decrease in intestinal iron absorption. The mechanism for this is unknown, but might involve a 'mucosal block' process similar to that proposed in iron overload, whereby increased expression of an enterocyte storage protein binds absorbed iron and prevents its transfer to the circulation. We examined the effect of disease-modifying therapy on ferritin expression in duodenal mucosa in RA to determine whether it may play a role in the 'mucosal block' process. Endoscopic small bowel biopsies were obtained from 11 patients with active RA both before, and 6 months after, a course of either gold or methotrexate (MTX). Mucosal ferritin levels in small bowel and stomach were measured by radio-immune assay. Duodenal mucosal ferritin decreased significantly following treatment (p <0.05). There were no changes in gastric mucosal ferritin. The fall in duodenal mucosal ferritin correlated with indices of disease activity at start of therapy, and the largest decreases were in those patients showing the best response to treatment in terms of a fall in inflammatory markers. Site-specific changes in mucosal ferritin may underlie the altered iron absorption observed in active inflammatory disease by modifying the enterocyte 'mucosal block'.   相似文献   
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A prospective blinded study of 201 patients was performed to determine the relative sensitivities and specificities of excretory urography/linear tomography (EU/LT) and ultrasound (US) for the diagnosis of renal parenchymal masses. Computed tomography (CT) was used as a standard. EU/LT permitted detection of 10% of CT-confirmed masses (cystic or solid) less than 1 cm, 21% of lesions greater than or equal to 1 cm but less than 2 cm, 52% of lesions greater than or equal to 2 cm but less than 3 cm, and 85% of lesions 3 cm or more in diameter. US permitted detection of 26% of CT-confirmed lesions less than 1 cm, 60% of lesions greater than or equal to 1 cm but less than 2 cm, 82% of lesions greater than or equal to 2 cm but less than 3 cm, and 85% of lesions 3 cm or more in size. The results confirm the relative insensitivity of EU/LT for masses less than 3 cm in diameter and of US for masses less than 2 cm. Further, they suggest that CT may have a role not only in evaluation of cases in which the urographic or sonographic results are questionable or positive, but also in confirmation of apparently negative urographic findings when clinical suspicion of a lesion is high.  相似文献   
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