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41.
N-ras gene point mutations in childhood acute lymphocytic leukemia correlate with a poor prognosis 总被引:2,自引:2,他引:2
Lubbert M; Mirro J Jr; Miller CW; Kahan J; Isaac G; Kitchingman G; Mertelsmann R; Herrmann F; McCormick F; Koeffler HP 《Blood》1990,75(5):1163-1169
Ras genes can be altered by point mutations at critical portions of their coding regions to acquire transforming ability in vitro. These point mutations have been detected in a variety of human malignancies. However, their relevance for the clinical and biologic behavior of the subgroups of patients exhibiting these mutations in unclear. We analyzed 100 patients with childhood acute lymphocytic leukemias (ALLs) for point mutations of exons 1 and 2 of all three ras genes (H-ras, K- ras, and N-ras) by polymerase chain reaction and a combination of oligonucleotide hybridization and direct DNA sequencing. A 6% incidence of N-ras gene mutations was detected, all of which occurred at different nucleotides of codons 12 or 13 of N-ras. When correlating presence of ras mutations with the clinical and biologic features and the clinical outcome of these cases, a significantly higher risk for hematologic relapse (P = .01) and a trend toward a lower rate of complete remission (P = .07) was noted. The two groups did not differ in any of the known high-risk factors of ALL. These results suggest that presence of an N-ras mutation in children with ALL may be an independent predictor for worse clinical outcome and therefore may have therapeutic implications; further studies to confirm these findings are required because of the small number of patients with N-ras mutations. 相似文献
42.
Chronic myelocytic leukemia (CML) is a clonal disorder involving neutrophil, monocyte, erythrocyte, and platelet precursors. In order to determine if the eosinophils are also involved in the leukemic clone, we purified the eosinophils from a woman heterozygous for the common electrophoretic variants of the G6PD gene. Only type B enzyme was demonstrable in the eosinophils, neutrophils, and red cells, but both A and B enzymes were found in the fibroblasts. The data provide evidence that the eosinophil is involved in the malignant clone. 相似文献
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Hepatic spiral CT: reduction of dose of intravenous contrast material 总被引:13,自引:0,他引:13
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Ambulatory sclerotherapy for malignant pleural effusions 总被引:12,自引:0,他引:12
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Thirteen patients who had undergone prolonged adrenocorticotropic hormone (ACTH) therapy for infantile spasms or myoclonic encephalopathy were examined with sonography. Nine patients were found to have appearances characteristic of medullary nephrocalcinosis. In each of these infants the cortical echogenicity was normal in the presence of focal areas of increased echogenicity within the renal pyramids. Five patients also showed a homogeneously increased echogenicity of the whole pancreas on sonography, and two of these showed increased density on computed tomography. Density measurements were in the range of calcific material within the papillae and pancreatic tissue. On abdominal survey radiographs, even in retrospect no calcifications could be recognized. 相似文献
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Digital imaging (digital image intensifier radiography, storage phosphor/selenium radiography) is increasingly becoming commonplace in radiology departments for diagnostic purposes. Despite 10 years of experience, the advantages and disadvantages of those methods are still heavily discussed among users, financiers and prescribers. This paper is to offer additional arguments for a thorough and objective discussion. No further comments or interpretations have been added to this paper. This paper consists of two main parts, A and B. The first part deals with the results of a user survey, the other part presents the results, i. e. statements, of a consensus conference. 相似文献