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A patient with Hodgkin’s disease received a fractionated 3, 740 rad dosage over 4 weeks to a portal that included both kidneys. Three months later a computed tomographic scan obtained 2 hours after intravenous contrast injection demonstrated sharply demarcated, dense, persistent nephrograms corresponding to the irradiated areas. These changes are ascribed to acute radiation nephritis, reflecting tubular stasis and ischemia. 相似文献
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Elevated levels of free putrescine and N1-acetylspermidine in cyst fluids of malignant brain tumours. 下载免费PDF全文
H Yamazaki T Tsukahara J Uki S Matsuzaki 《Journal of neurology, neurosurgery, and psychiatry》1986,49(2):209-210
The contents of free and conjugated polyamines in cyst fluids of brain tumours were analysed. The putrescine and N1-acetylspermidine levels in cyst fluids of malignant brain tumours were significantly higher than those of benign tumours. The free spermidine levels in malignant and benign tumours were about the same, while the total spermidine levels were higher in malignant than those in benign tumours. These results suggest that polyamine levels in cyst fluids reflect the altered polyamine metabolism in brain tumours. 相似文献
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Katherine A Hillman Tanya M Johnson Paul J D Winyard Geoffrey Burnstock Robert J Unwin Adrian S Woolf 《Experimental nephrology》2002,10(1):34-42
BACKGROUND: Purinergic receptors are cell-surface molecules that bind extracellular nucleotides, notably ATP. The P2X family includes seven nonselective ion channels with one member, P2X(7), implicated in cytolytic pore formation and cell death. MATERIALS AND METHODS: We sought P2X(7) expression in mouse nephrogenesis and cpk/cpk renal cyst growth, conditions in which both proliferation and apoptosis are prominent. RESULTS: P2X(7) immunolocalized to condensed metanephric mesenchyme: both proliferation and apoptosis were detected in this compartment, assessed by proliferating cell nuclear antigen expression and propidium iodide-stained pyknotic nuclei respectively. Later in nephrogenesis, P2X(7) was detected in collecting ducts, a pattern persisting to maturity. A mesenchymal to epithelial shift of P2X(7) expression was also documented in ureter development. In cpk/cpk kidneys, P2X(7)-expressing collecting duct cysts dominated histology from two weeks until four weeks after birth, when animals die from uremia. In polycystic kidneys pyknotic nuclei were rarely identified in P2X(7)-expressing epithelia, but were detected between cysts, consistent with a non-apoptotic role for P2X(7) in cyst enlargement. CONCLUSION: P2X(7) is expressed during normal nephrogenesis and in a model of congenital polycystic kidney disease. Further experiments are necessary to define possible functions of P2X(7) in these settings. 相似文献