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21.
Aims: The aim of this study was to develop and refine a decision rule on when to undertake brain imaging (BI) in neurologically normal children with headaches. Methods: From the literature and a questionnaire study, a list of red flags (RFs) was drawn‐up. During the prospective 4‐year period, consecutive children with headache were classified according to RFs and the headache diagnosis. Result: Three of 709 (0.4%) neurologically normal children had significant brain abnormalities. BI was carried out in 389 of 498 (78%) children with RFs. Significant abnormalities were found in three of 389 children (0.8%), all had unclassified headache (UH). BI was not arranged for the 211 children with no RFs. None of these developed RFs or abnormal signs on follow‐up for a mean of 13 months. Conclusion: In addition to BI for those with neurological signs, we think BI should be considered for neurologically normal patients with UH and RFs. This would have saved imaging children needlessly: only 101 of 709 (14%) would have had scans arranged, instead of 389 of 709.  相似文献   
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Jolles  PR; Shin  MS; Jones  WP 《Radiology》1986,159(3):647-651
A retrospective morphologic study of 80 cases was undertaken to determine factors affecting detectability of computed tomographically (CT) proved aortopulmonary (AP) window lesions on conventional posteroanterior (PA) and lateral chest radiographs. Criteria used for determining abnormality were: solitary lymph node enlargement over 1.5 cm or three or more 1-cm nodes and obvious large masses or vascular anomalies. CT scans and corresponding PA and lateral radiographs were analyzed for lesion detectability, size, and location. In 49% of cases there was no detectable lesion in the AP window on radiographs; a definite AP window lesion was seen in 41%, and 10% were equivocal. Major contributing factors to low detectability of AP window lesions on radiographs include size and, more important, location of the lesion. An additional 45 cases of CT-proved normal AP windows were retrospectively reviewed to determine the false-positive rate of PA and lateral radiographs in detection of AP window lesions: 43 (96%) were classified as negative, the remaining two (4%) as equivocal. Although the AP window is a small space, it is the site of many pathologic conditions; the study results indicate that CT may be an essential procedure for its evaluation.  相似文献   
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High-resolution P-31 MR spectra were obtained in four patients with bone tumors of their distal extremities. In one case the tumor, a Ewing sarcoma of the tibia, was investigated during clinical remission after radiation therapy and chemotherapy. The other three cases - one low-grade chondrosarcoma of the tibial head, one malignant fibrous histiocytoma of the tibia, and one chondroblastoma of the medial femoral condyle - showed clinically active tumor growth, with corresponding increased metabolism as demonstrated by bone scintigraphy. The spectra of the three active tumors indicated a comparably high adenosine triphosphate content, similar to previously published spectra from animal tumors or human tumors implanted into animals. There were also high resonances of inorganic phosphate and low resonances of phosphocreatine; there were definite peaks in the phosphodiester and phosphomonoester regions, indicating the existence of these metabolites in the tumors. Slight but definite changes in the metabolite content were observed in one tumor after chemotherapy. The spectra of the unaffected leg did not show any well-resolved P-31 signals, which is typical for healthy bone. These are the first P-31 MR spectra of human bone tumors measured in patients to our knowledge.  相似文献   
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Epidural lipomatosis   总被引:10,自引:0,他引:10  
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To determine the value of sonography in the emergent evaluation of suspected leaking abdominal aortic aneurysms, the authors examined 60 patients in the emergency department using sonography and a protocol involving advance radio notification from the ambulance; arrival of sonographic personnel and equipment in the triage room before patient arrival; and, during other triage activities, rapid sonographic evaluation of the aorta for aneurysm and of the paraaortic region for extraluminal blood. Sonographic findings were correlated with surgical results and clinical outcome. When performed under these circumstances, sonography was accurate in demonstrating presence or absence of aneurysm (98%), but its sensitivity for extraluminal blood was poor (4%). A combination of sonographic confirmation of aneurysm, abdominal pain, and unstable hemodynamic condition resulted in the correct decision to perform emergent surgery in 21 of 22 patients (95%). An abbreviated sonographic examination done in the emergency room can provide accurate, useful information about the presence of aneurysm; this procedure does not significantly delay triage of these patients.  相似文献   
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Hammond  WP; Dale  DC 《Blood》1982,59(1):179-184
The cycling of blood cell counts in grey collie dogs with cyclic hematopoiesis can be eliminated by treatment with oral lithium carbonate. To explore the mechanism by which lithium alters this stem cell disorder, studies of bone marrow granulocyte-macrophage progenitor cells (CFU-C), neutrophil colony-forming cells (neutrophilic CFU-C), and colony-stimulating activity (CSA) were performed. In untreated dogs, the proportions of CFU-C were found to fluctuate cyclically, but the cyclic fluctuations in neutrophil colony-forming cells were even more marked, with numbers decreasing to undetectable levels during each period of neutrophilia. Dogs on lithium, however, did not cycle the numbers of total or neutrophilic CFU-C. Tritiated thymidine suicide rates were not altered by treatment with lithium. Serum CSA levels and bone marrow cell elaboration of CSA were not increased by lithium. These studies suggest that lithium corrects cyclic neutropenia by a direct effect on the differentiation and proliferation of CFU-C; normalization of the proportion of CFU-C that enter neutrophilopoiesis appears to be an important effect of the lithium therapy.  相似文献   
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