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Of 41 cases of acute paracetamol poisoning one died of gastrointestinal haemorrhage and acute massive necrosis of the liver, three became jaundiced, and 13 others had biochemical evidence of hepatocellular damage. Liver damage is a toxic effect which is present in most patients who ingest more than 15 g. of paracetamol. One patient with liver damage survived renal failure due to acute tubular necrosis. It is suggested that the renal lesion was also the result of paracetamol overdosage.Profound hypoglycaemia and metabolic acidosis may also complicate severe poisoning. Plasma levels of para-aminophenol fall rapidly, and procedures currently used to enhance the elimination of the drug cannot be expected to prevent development of hepatic damage. 相似文献
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Conversion of dethiobiotin to biotin in Aspergillus niger 总被引:1,自引:0,他引:1
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A high frequency of distinct ATM gene mutations in ataxia-telangiectasia. 总被引:10,自引:1,他引:9 下载免费PDF全文
J. Wright S. Teraoka S. Onengut A. Tolun R. A. Gatti H. D. Ochs P. Concannon 《American journal of human genetics》1996,59(4):839-846
The clinical features of the autosomal recessive disorder ataxia-telangiectasia (AT) include a progressive cerebellar ataxia, hypersensitivity to ionizing radiation, and an increased susceptibility to malignancies. Epidemiological studies have suggested that AT heterozygotes may also be at increased risk for malignancy, possibly as a consequence of radiation exposure. A gene mutated in AT patients (ATM) has recently been isolated, making mutation screening in both patients and the general population possible. Because of the relatively large size of the ATM gene, the design of screening programs will depend on the types and distribution of mutations in the general population. In this report, we describe 30 mutations identified in a panel of unrelated AT patients and controls. Twenty-five of the 30 were distinct, and most patients were compound heterozygotes. The most frequently detected mutation was found in three different families and had previously been reported in five others. This corresponds to a frequency of 8% of all reported ATM mutations. Twenty-two of the alterations observed would be predicted to lead to protein truncation at sites scattered throughout the molecule. Two fibroblast cell lines, which displayed normal responses to ionizing radiation, also proved to be heterozygous for truncation mutations of ATM. These observations suggest that the carrier frequency of ATM mutations may be sufficiently high to make population screening practical. However, such screening may need to be done prospectively, that is, by searching for new mutations rather than by screening for just those already identified in AT families. 相似文献
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