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111.
Renal angiography using carbon dioxide 总被引:1,自引:0,他引:1
The many advantages of carbon dioxide (CO2) angiography in the investigation of renal arterial disease include an absence of both nephrotoxicity and allergic reactions. An automated delivery system facilitates injection of CO2 whilst ensuring that there is no contamination of the injection with air. We report our initial experience using a prospective study of this delivery system in 47 patients referred for renal angiography, and assess diagnostic image quality and adverse reactions to CO2 angiography using the automated delivery system. The majority (37/47; 79%) of angiograms were of diagnostic quality and there were no significant adverse reactions in response to the CO2 contrast agent. 相似文献
112.
AIM: To determine the role of microbubble-enhanced colour Doppler ultrasound (CDUS) in assessing portal venous patency prior to liver transplantation. MATERIALS AND METHODS: Over a 2-year period, all patients with chronic liver disease undergoing routine pre-transplant CDUS examination in whom the portal venous system was inadequately demonstrated were recruited to the study. CDUS was performed in 368 patients and 33 patients (9%) were recruited. A repeat CDUS examination following an intravenous bolus injection of the microbubble contrast agent Levovist (Schering Healthcare AG, Berlin, Germany) was performed. Diagnostic confidence was recorded on a free linear analogue scale for both examinations. Findings were compared with indirect portography and surgery. RESULTS: Of the 33 patients with sub-optimal baseline examinations, improvement in portal vein visualization was achieved in 31 patients (94%). Median diagnostic confidence increased from 50% (interquartile range 30-60) to 90% (interquartile range 75-98) (P < 0.001) following administration of Levovist. Overall accuracy of portal vein assessment using microbubble-enhanced CDUS in 15 patients in whom a definitive diagnosis was made within 2 months was 87%. CONCLUSION: Microbubble-enhanced CDUS is a simple, inexpensive adjunct to standard pre liver transplant screening of the portal vein. It is particularly helpful in patients with end-stage cirrhosis who are at high risk of portal vein thrombosis and in whom the conventional examination is sub-optimal. 相似文献
113.
We report a case of extensive fatty change in a Wilms' tumour after chemotherapy demonstrated on CT associated with an increase in tumour volume, in a 10-month-old girl with Beckwith-Wiedemann syndrome. Changes in tumour characteristics after chemotherapy on imaging usually reflect necrosis, haemorrhage and calcification. Assessment of response to therapy is dependent on a documented reduction in tumour volume. In this case, CT showed an increase in tumour size with development of an extensive fatty component following treatment. Subsequent histological examination on the nephrectomy specimen confirmed an extensive fatty component with no evidence of residual blastema. The development of such an extensive fatty component is very unusual. In this case such fatty change was an indicator of tumour sensitivity and response to treatment. 相似文献
114.
Dose-dependent localization of TCDD in isolated centrilobular and periportal hepatocytes 总被引:3,自引:1,他引:2
Santostefano MJ; Richardson VM; Walker NJ; Blanton J; Lindros KO; Lucier GW; Alcasey SK; Birnbaum LS 《Toxicological sciences》1999,52(1):9-19
Dose-response relationships for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)
suggest a differential sensitivity of liver cell types to the induction of
cytochrome P450 gene expression, and that the induction of hepatic protein
CYP1A2 causes sequestration of TCDD. In addition, immunolocalization of
hepatic CYP1A1/1B1/1A2 proteins is not uniform after exposure to TCDD. The
mechanism for the regio-specific induction of hepatic P450s by TCDD is
unknown, but may involve the differential distribution of participants in
the AhR-mediated pathway and/or regional P450 isozymes, as well as,
non-uniform distribution/sequestration of TCDD. Therefore, this study
examined the effects of TCDD in unfractionated, centrilobular and
periportal hepatocytes isolated from female Sprague-Dawley rats acutely
exposed (3 days) to a single oral dose of 0.01-10.0 microg [3H]TCDD/kg. A
dose- dependent increase in concentration of TCDD was accompanied by a
dose- dependent increase in CYP1A1, CYP1A2, and CYP1B1 mRNA expression and
associated enzymes in all liver-cell populations. Centrilobular hepatocytes
showed a 2.7- to 4.5-fold higher concentration of TCDD as compared to the
periportal hepatocytes at doses up to 0.3 microg TCDD/kg. Centrilobular
hepatocytes also exhibited an elevated MROD activity as compared to the
periportal hepatocytes at doses up to 0.3 microg TCDD/kg. Furthermore,
centrilobular hepatocytes showed an elevated concentration of induced
CYP1A2 and CYP1B1 mRNA as compared to periportal hepatocytes within the
0.01- and 0.3-microg TCDD/kg- treatment groups. This is the first study to
demonstrate that a dose- dependent difference in distribution of TCDD
exists between centrilobular and periportal cells that might be related to
regional differences in P450 induction.
相似文献
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117.
Nebulized budesonide versus oral steroid in severe exacerbations of childhood asthma 总被引:10,自引:0,他引:10
EE Matthews PD Curtis BI McLain LS Morris ML Turbitt 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(8):841-843
The aim of this study was to assess whether nebulized budesonide may substitute for oral prednisolone in the management of children whose asthma is severe enough to warrant hospital admission, but who have no life threatening features. In a prospective, double-blind, randomized study nebulized budesonide (2 mg 8 hourly) was compared with oral prednisolone (2 mg/kg at entry and again at 24 h) in 46 children admitted to hospital with severe asthma exacerbations. Efficacy variables (including lung function measurements such as the primary outcome variable, Forced Expiratory Volume in 1 second (FEV1) and symptoms) were measured 24 h after treatment initiation. FEV1 improved significantly compared to baseline in patients who received nebulized budesonide compared to the prednislone group. The data show nebulized budesonide to be at least as effective as oral steroid in improving lung function and symptom severity in severe exacerbations of childhood asthma. 相似文献
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119.
弯喙乌头的化学成分研究 总被引:1,自引:0,他引:1
从弯喙乌头(Aconitum campylorrhynchum)中分离出一个微量新生物碱,经光谱和化学方法证明为8-乙酰嘟啦碱-(8-acetytdolaconine,Ⅰ),同时分离得到2个已知生物碱;即嘟啦碱(Ⅱ)和aconosine,(Ⅲ),后者是该植物的主要生物碱成分,在非生物碱部分还分离得到β-谷甾醇,棕榈酸和香豆酸。 相似文献
120.