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51.
Marinus J. Becks Rashindra Manniesing Jeroen Vister Sjoert A.H. Pegge Stefan C.A. Steens Ewoud J. van Dijk Mathias Prokop Frederick J.A. Meijer 《Journal of neuroradiology. Journal de neuroradiologie》2019,46(2):124-129
Background and purpose
To evaluate whether brain CT perfusion (CTP) aids in the detection of intracranial vessel occlusion on CT angiography (CTA) in acute ischemic stroke.Materials and methods
Medical-ethical committee approval of our hospital was obtained and informed consent was waived. Patients suspected of acute ischemic stroke who underwent non-contrast CT(NCCT), CTA and whole-brain CTP in our center in the year 2015 were included. Three observers with different levels of experience evaluated the imaging data of 110 patients for the presence or absence of intracranial arterial vessel occlusion with two strategies. In the first strategy, only NCCT and CTA were available. In the second strategy, CTP maps were provided in addition to NCCT and CTA. Receiver-operating-characteristic (ROC) analysis was used for the evaluation of diagnostic accuracy.Results
Overall, a brain perfusion deficit was scored present in 87–89% of the patients with an intracranial vessel occlusion, more frequently observed in the anterior than in the posterior circulation. Performance of intracranial vessel occlusion detection on CTA was significantly improved with the availability of CTP maps as compared to the first strategy (P = 0.023), due to improved detection of distal and posterior circulation vessel occlusions (P-values of 0.032 and 0.003 respectively). No added value of CTP was found for intracranial proximal vessel occlusion detection, with already high accuracy based on NCCT and CTA alone.Conclusion
The performance of intracranial vessel occlusion detection on CTA was improved with the availability of brain CT perfusion maps due to the improved detection of distal and posterior circulation vessel occlusions. 相似文献52.
Lianne J. Stevens Joanne M. Donkers Jeroen Dubbeld Wouter H. J. Vaes Catherijne A. J. Knibbe Ian P. J. Alwayn 《Drug metabolism reviews》2020,52(3):438-454
AbstractTo predict the absorption, distribution, metabolism and excretion (ADME) profile of candidate drugs a variety of preclinical models can be applied. The ADME and toxicological behavior of newly developed drugs are often investigated prior to assessment in humans, which is associated with long time-lines and high costs. Therefore, good predictions of ADME profiles earlier in the drug development process are very valuable. Good prediction of intestinal absorption and renal and biliary excretion remain especially difficult, as there is an interplay of active transport and metabolism involved. To study these processes, including enterohepatic circulation, ex vivo tissue models are highly relevant and can be regarded as the bridge between in vitro and in vivo models. In this review the current in vitro, in vivo and in more detail ex vivo models for studying pharmacokinetics in health and disease are discussed. Additionally, we propose novel models, i.e., perfused whole-organs, which we envision will generate valuable pharmacokinetic information in the future due to improved translation to the in vivo situation. These machine-perfused organ models will be particularly interesting in combination with biomarkers for assessing the functionality of transporter and CYP450 proteins. 相似文献
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Influence of WHO versus ELN advanced phase chronic myeloid leukemia definitions on overall survival 下载免费PDF全文
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Left ventricular reverse remodeling after aortic valve surgery for acute versus chronic aortic regurgitation 下载免费PDF全文
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