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161.
Philip J. Currie MBBS Michael J. Kelly FRACP Aubrey Pitt FRACP 《The American journal of cardiology》1983,52(10):1167-1173
Exercise-induced electrocardiographic ST depression was compared during supine and erect graded bicycle exercise in 43 patients with chest pain but no prior myocardial infarct; all had ≥1 mm of ST depression during either erect or supine exercise; 16 had multivessel, 24 had 1-vessel and 3 had no coronary artery disease. Supine exercise used 4 minutes/stage and erect exercise used either 4 minutes or 3 minutes/stage with identical graded work loads for both postures. Chest pain occurred in 31 patients during erect and in 29 during supine exercise. ST depression was ≥1 mm in 28 patients during erect exercise and in all 43 during supine exercise (p <0.001); mean maximal ST depression was 1.3 ± 0.2 mm during erect and 2.6 ± 0.2 mm during supine exercise (p <0.001). Maximal work load was higher during erect than supine exercise (745 ± 32 versus 678 ± 32 kpm/min; p <0.001). The accentuation of ST depression by supine posture was not attributable to the changes in heart rate, rate-pressure product or mean blood pressure during supine versus erect exercise. In the 10 patients who had 2 erect bicycle tests using work load durations of 3 and 4 minutes, the maximal ST depression was not significantly different (erect 3 minutes 1.3 ± 0.5 mm and erect 4 minutes 1.4 ± 0.4 mm). In 7 patients who also had a maximal treadmill exercise test, the maximal ST depression was significantly greater during supine exercise (2.3 ± 0.4 mm) than during either an erect bicycle test (0.6 ± 0.4 mm) or treadmill exercise (0.7 ± 0.4 mm) (p <0.05). Supine posture should be considered as an important potentiator of exercise-induced myocardial ischemia whem comparing indicators such as electrocardiography, radionuclide ventriculography and thallium-201 myocardial perfusion imaging during exercise. 相似文献
162.
Thomas Klopstock MD Aleksandar Videnovic MD Almut Turid Bischoff MD Cecilia Bonnet MD Laura Cif MD Cynthia Comella MD Marta Correa-Vela MD Maria L. Escolar MD Jamie L. Fraser MD Victoria Gonzalez MD Neal Hermanowicz MD Robert Jech MD Hyder A. Jinnah MD Tomasz Kmiec MD Anthony Lang MD Maria J. Martí MD Saadet Mercimek-Andrews MD Migvis Monduy MD Graeme A.M. Nimmo MBBS Belen Perez-Dueñas MD Helle Cecilie Viekilde Pfeiffer MD Lluis Planellas MD Emmanuel Roze MD Nivedita Thakur MD Laura Tochen MD Nora Vanegas-Arroyave MD Giovanna Zorzi MD Colleen Burns PhD Feriandas Greblikas MD 《Movement disorders》2021,36(6):1342-1352
163.
Mustafa R. Bashir MD Lubna Bhatti MBBS Daniele Marin MD Rendon C. Nelson MD 《Journal of magnetic resonance imaging : JMRI》2015,41(4):884-898
Ferumoxytol is an ultrasmall superparamagnetic iron oxide (USPIO) agent initially approved by the Food and Drug Administration (FDA) as an iron replacement therapy for patients with anemia due to chronic renal failure. Recently, ferumoxytol has been investigated extensively as an intravenous contrast agent in magnetic resonance imaging (MRI). Since it causes regional T1 and T2* shortening in vivo, conventional pulse sequences can be used following ferumoxytol administration to demonstrate signal enhancement or loss. Ferumoxytol can be administered as a rapid bolus and has a long intravascular half‐life on the order of 14–15 hours, making it a potentially useful agent for vascular and perfusion‐weighted MRI. In comparison to other USPIOs, ferumoxytol is less limited by allergic and idiosyncratic reactions. Furthermore, since ferumoxytol is an iron‐based agent with no potential for causing nephrogenic systemic fibrosis, it may be useful as an alternative to gadolinium‐based contrast agents in patients with compromised renal function. Ferumoxytol is ultimately taken up by macrophages/the reticuloendothelial system in the liver, spleen, and lymph nodes, and this uptake mechanism is being explored as a novel imaging technique for vascular lesions, tumors, and lymph nodes. This article reviews the properties of ferumoxytol relevant to MRI as well as many of the uses for the agent currently under investigation. J. Magn. Reson. Imaging 2015;41:884–898 . © 2014 Wiley Periodicals, Inc . 相似文献
164.
Inlet and outlet valve flow and regurgitant volume may be directly and reliably quantified with accelerated,volumetric phase‐contrast MRI 下载免费PDF全文
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166.
Primary stroke prevention in Nigerian children with sickle cell disease (SPIN): Challenges of conducting a feasibility trial 下载免费PDF全文
Najibah A. Galadanci MBBS FMCPath Shehu U. Abdullahi MD FWACPaed Musa A. Tabari MBBS FMCR FICS Shehi Abubakar MBBS Raymond Belonwu MBBS FWACPaed Auwal Salihu MBBS FMCPsych Kathleen Neville MD MS Fenella Kirkham MD FRCP FRCPCH Baba Inusa MD FRCPCH DCP Yu Shyr PhD Sharon Phillips MSPH Adetola A. Kassim MBBS FMCPath Lori C. Jordan MD PhD Muktar H. Aliyu MBBS MPH DrPH Brittany V. Covert MPH Michael R. DeBaun MD MPH 《Pediatric blood & cancer》2015,62(3):395-401
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Patient knowledge and perception of computed tomography scan in the management of chronic rhinosinusitis symptoms 下载免费PDF全文
170.