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91.
Smith  R; Rosen  JM; Gallo  LN; Alderson  PO 《Radiology》1985,156(3):797-800
Gallbladder nonvisualization in cholescintigraphy has been shown to be a reliable finding in acute cholecystitis. In some cholescintigrams, we have observed faintly increased pericholecystic hepatic activity in conjunction with gallbladder nonvisualization. To determine the frequency and significance of the pericholecystic hepatic activity finding, we evaluated 334 consecutive adult patients who had cholescintigrams with technetium-99m diisopropylphenylcarboamoyl iminodiacetic acid. Pericholecystic hepatic activity was seen in 21% of the abnormal scans demonstrating gallbladder nonvisualization but in none of the other scans. Thirteen of these patients underwent surgery; 11 (85%) were found to have acute cholecystitis, and two (15%) had chronic cholecystitis. Four patients (31%) had acute gangrenous cholecystitis, and five (39%) had cholecystitis complicated by gallbladder perforation. The pericholecystic hepatic activity sign is not specific for gangrenous cholecystitis or gallbladder perforation but does reliably indicate inflammatory gallbladder disease and is associated with a relatively high incidence of cholecystitis complicated by perforation.  相似文献   
92.
Although five patients with severe pre-eclamptic toxaemia (PET) had increased anticomplementary activity in their serum, there was no evidence of complement activation in the plasma of four of the five patients. These results are not implicated in the pathogenesis of PET. No significant correlation was found between anticomplementary activity and pregnancy-associated alpha2-glycoprotein.  相似文献   
93.
Myelolipoma of the adrenal gland is a rare tumor composed of varying proportions of fat and bone marrow elements. In about half of the reported cases with radiologic findings the mass was radiolucent, indicating the presence of fat; the remainder were of soft tissue density or calcified. Arteriography is of limited value in diagnosis, since myelolipomas are typically avascular. With the advent of gray scale ultrasound and computed tomography (CT), fat can be detected in lesions which do not appear radiolucent on radiographs. Two cases of myelolipoma are reported in which ultrasound showed a markedly echogenic mass, an appearance chracteristic of lipomatous tumors. In the second case, the mass was of soft tissue density on radiographs, markedly echogenic on sonogram, and definitively fatty on CT scan. Ultrasound and CT are valuable techniques for making a preoperative diagnosis of this tumor.  相似文献   
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Terminals of the commissural projection in the cat were characterized ultrastructurally by autoradiographic and horseradish peroxidase methods. The results of the two studies are complementary. Terminals of commissural cells are present in the intermediate and deep layers of the cat superior colliculus. Two distinct populations of terminals are present: one containing mostly round vesicles and forming asymmetric specializations, and a second containing mostly pleomorphic vesicles and forming symmetric specializations. Both populations contact small dendrites or dendritic appendages. The two populations, mostly round and mostly pleomorphic, are present in the ratio of 2:1. Terminals measure approximately 1.1 micron in mean diameter and contact profiles ranging in size from 0.2 to 4.6 micron. There is no significant difference between the two populations in either pre- or postsynaptic profile size. The colocalization of terminals of commissural neurons with other afferent and efferent projections of the intermediate layers of the superior colliculus is discussed.  相似文献   
96.
The possibility that acute disseminated encephalomyelitis (ADEM) and epidemic myalgic encephalomyelitis (''epidemic neuromyasthenia'') may share a common pathogenesis is examined and many factors common to the two diseases are described. It is suggested that further study of ADEM may help our understanding of epidemic myalgic encephalomyelitis.  相似文献   
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The relationship between the group B Coxsackieviruses and a wide variety of illnesses, particularly pleurodynia and myo/pericarditis, is already well established. The detection of raised levels of neutralizing antibody to these viruses in a group of patients in a rural practice presenting with an illness resembling myalgic encephalomyelitis (ME) was therefore unexpected. This is a most distressing and debilitating illness for the patient and the affected family. What is the immunological failure in these patients which apparently allows this virus to persist causing such unusual and bizarre illness? At present ME is probably much commoner than is realized, the majority of patients being given the dismissive diagnosis of psychoneurosis.  相似文献   
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