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11.
妊娠肝内胆汁淤积症患者血清一氧化氮和内皮素的变化及意义 总被引:2,自引:0,他引:2
目的:探讨妊娠肝内胆汁淤积症(ICP)患者外周静脉血清、新生儿脐静脉血清中一氧化氮(NO)、内皮素(ET)、丙二醛(MDA)和超氧化物歧化酶(SOD)含量的变化及在ICP发病中的作用。方法:以ICP组28例为研究组,测定其外周静脉血清及新生儿脐静脉血清中的NO、ET、MDA和SOD,以年龄相近的24例正常孕妇作为对照组。结果:ICP患者的MDA和ET含量较正常晚期妊娠显著增高(P<0.01),ICP患者的NO和SOD含量与对照组相比无显著性差异(P>0.05)。母血清中NO、ET、MDA含量均较新生儿脐静脉血清中的含量高,差异有显著性(P<0.01)。结论:妊娠期体内氧化和抗氧化失衡及ET水平的增高可能与ICP的发生、发展有关。 相似文献
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Hepatic processing of transforming growth factor beta in the rat. Uptake, metabolism, and biliary excretion. 总被引:21,自引:7,他引:14 下载免费PDF全文
R J Coffey Jr L J Kost R M Lyons H L Moses N F LaRusso 《The Journal of clinical investigation》1987,80(3):750-757
Transforming growth factor beta (TGF beta), a recently discovered polypeptide, modulates growth of normal and neoplastic cells. Since little is known concerning in vivo disposition of TGF beta, we performed studies to examine the hepatic processing of biologically active 125I-TGF beta in the rat. After intravenous injection, 125I-TGF beta disappeared from the plasma with an initial t1/2 of 2.2 min; partial hepatectomy delayed the plasma disappearance of 125I-TGF beta by 80%. 60 min after intrafemoral injection, 63% of the recovered label was present in liver and/or bile; by 90 min, most of the label removed by the liver (83%) had been slowly excreted into bile. Nearly all the label in bile (96%) was soluble in trichloracetic acid and not immunoprecipitable by specific antiserum. Colchicine and vinblastine inhibited cumulative biliary excretion of label by 28 and 37%, respectively; chloroquine and leupeptin each increased the amount of label in bile that was precipitable by trichloracetic acid and that coeluted with authentic 125I-TGF beta on molecular sieve chromatography. There was efficient first-pass hepatic extraction of 125I-TGF beta (36%) in the isolated perfused rat liver, which was inhibited by unlabeled TGF beta (but not by epidermal growth factor, EGF) and by lectins in a dose-dependent manner; prolonged fasting also decreased clearance (26%). After fractionation of liver by differential or isopycnic centrifugation, radiolabel codistributed with marker enzymes for lysosomes. The results indicate rapid, extensive, inhibitable, and organ-selective extraction of TGF beta by the liver. After extraction, TGF beta undergoes efficient transhepatic transport, extensive intracellular metabolism, and slow but complete biliary excretion of its metabolites. Liver fractionation studies and pharmacologic manipulations suggest that these processes are associated with organelles that include microtubules and lysosomes. The data suggest that the liver is a major target tissue or site of metabolism for biologically active TGF beta. 相似文献
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G. P. Sadler S. McGee N. S. Dallimore I. J. Monypenny A. G. Douglas-Jones Mr K. Lyons K. Horgan 《The British journal of surgery》1994,81(9):1315-1317
Fine-needle aspiration cytology (FNAC) plays a key role in the preoperative diagnosis of carcinoma of the breast but is less reliable in the diagnosis of infiltrating lobular carcinoma. The method of diagnosis was reviewed in 56 patients with lobular carcinoma who had attended screening and symptomatic clinics. In 29 patients FNAC results demonstrated malignant cells; 15 of these had palpable disease and the mean tumour size was 21 mm. In 27 patients FNAC failed to demonstrate malignant cells; 13 lesions were palpable and the mean tumour size was 23 mm. Ten patients were diagnosed by needle-core biopsy when FNAC was not diagnostic. FNAC may fail to diagnose even large lobular carcinoma and needle-core biopsy is strongly recommended in this situation. 相似文献
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Occupational therapy is based on core values of altruism, equality, and honoring the dignity of others. Embedded in these values is the ever-present negotiation of power. To honor the concern for the welfare of others, researchers are challenged to think about issues of power throughout the research process. This paper identifies dilemmas and raises questions researchers might ask themselves as they struggle to share power in the interpretive research process. 相似文献
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M Lyons 《Sexually transmitted infections》1994,70(2):138-145
First noticed in Uganda in 1863 by a European explorer, sexually transmitted diseases (STDs) were cited as a major cause of morbidity and mortality throughout this century. In 1908 the venereal diseases campaign was launched marking the real introduction of western medicine. By the mid-1920s, the campaign was combined with the medical service but throughout the colonial period (1901-1962) venereal diseases were considered intractable. A 1991 survey revealed alarming incidence rates and in light of the importance of STDs as a co-factor in the transmission of HIV, it is of paramount importance to implement more effective control measures. 相似文献