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Elizabeth Juneman Layth Saleh Hoang Thai Steven Goldman Mohammad Reza Movahed 《Experimental & Clinical Cardiology》2012,17(1):17-19
A history of severe allergic reaction to iodine contrast leading to anaphylactic shock presents a dilemma in patients requiring cardiac catheterization. As an alternative, gadolinium has been an interesting and potentially useful agent. However, gadolinium produces poor image quality and has been associated with significant arrhythmias in small case series. Furthermore, there is no consensus about the maximal allowable dose that can be administered to a patient. In the present report, a successful combination of gadolinium contrast with a power injector that produced adequate image quality in a patient with severe allergy to iodine contrast is described. The case was complicated by the occurrence of ventricular fibrillation when damping occurred during injection of contrast into the right coronary artery. This complication has been reported previously with intracoronary gadolinium injection. The report is followed by a brief literature review. 相似文献
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Maryam Shojaeifard MD Sedigheh Saedi MD Alireza Alizadeh Ghavidel MD Mohammad Reza Karimlu MD Mohammad Kasaei MD Hamid Reza Pouraliakbar MD Kambiz Mozaffari MD 《Echocardiography (Mount Kisco, N.Y.)》2020,37(3):462-464
Primary tumors of the heart are rare with a reported incidence of about 0.002% to 0.3% at autopsy. A cardiac hemangioma is a form of benign primary cardiac tumor that often presents with atypical clinical symptoms. Hemangiomas are generally isolated lesions. Here, we report a patient with previous hepatic hemangioma who later was found to have a large coexistent cardiac hemangioma presenting with cardiac compressive symptoms. 相似文献
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High rate of A2142G point mutation associated with clarithromycin resistance among Iranian Helicobacter pylori clinical isolates 下载免费PDF全文
Reza Khashei Mahintaj Dara Abdollah Bazargani Kamran Bagheri Lankarani Alireza Taghavi Maryam Moeini Behzad Dehghani Maryam Sohrabi 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(9):787-793
This study aimed to investigate the clarithromycin resistance and its associated molecular mechanisms among Helicobacter pylori isolates from dyspeptic patients in Shiraz, Iran. From January to May 2014, 100 H. pylori strains were isolated from patients with gastroduodenal disorders. The resistance to clarithromycin was quantitatively evaluated, using Epsilometer (E‐test) method. Polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) was performed on all the isolates to detect A2143G and A2142G mutations in 23S rRNA gene. The H. pylori isolation rate was found to be 31.4%. E‐test showed that 20% of isolates were resistant to clarithromycin (MIC ≥ 1 mg/L). MIC of clarithromycin ranged between 0.016 and 24 mg/L. Findings of PCR‐RFLP showed that the A2142G was the most (90%) frequently point mutation, followed by the A2143G (10%). No statistically significant difference was found between H. pylori clarithromycin resistance point mutations and patients’ gender or age. To the best of our knowledge, this is the first report of high frequency of A2142G point mutation in Iran and probably in other regions of the world. Considering the increasing trend of H. pylori resistance to clarithromycin due to these mutations, it is crucial to investigate the new therapeutic approaches against H. pylori infection. 相似文献
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Samuel John Fahrenholtz Reza Madankan Shabbar Danish John D. Hazle R. Jason Stafford David Fuentes 《International journal of hyperthermia》2018,34(1):101-111
Purpose: Neurosurgical laser ablation is experiencing a renaissance. Computational tools for ablation planning aim to further improve the intervention. Here, global optimisation and inverse problems are demonstrated to train a model that predicts maximum laser ablation extent.Methods: A closed-form steady state model is trained on and then subsequently compared to N?=?20 retrospective clinical MR thermometry datasets. Dice similarity coefficient (DSC) is calculated to provide a measure of region overlap between the 57?°C isotherms of the thermometry data and the model-predicted ablation regions; 57?°C is a tissue death surrogate at thermal steady state. A global optimisation scheme samples the dominant model parameter sensitivities, blood perfusion (ω) and optical parameter (μeff) values, throughout a parameter space totalling 11?440 value-pairs. This represents a lookup table of μeff–ω pairs with the corresponding DSC value for each patient dataset. The μeff–ω pair with the maximum DSC calibrates the model parameters, maximising predictive value for each patient. Finally, leave-one-out cross-validation with global optimisation information trains the model on the entire clinical dataset, and compares against the model naïvely using literature values for ω and μeff.Results: When using naïve literature values, the model’s mean DSC is 0.67 whereas the calibrated model produces 0.82 during cross-validation, an improvement of 0.15 in overlap with the patient data. The 95% confidence interval of the mean difference is 0.083–0.23 (p?0.001).Conclusions: During cross-validation, the calibrated model is superior to the naïve model as measured by DSC, with +22% mean prediction accuracy. Calibration empowers a relatively simple model to become more predictive. 相似文献
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Khadijeh Jamialahmadi Hamid Reza Sadeghnia Ghazaleh Mohammadi Ali Masoudi Kazemabad Mahmoud Hosseini 《Pathophysiology》2013,20(4):263-267
Introduction and objectiveBeneficial effects of glucosamine in spatial learning and memory impairment induced by scopolamine has been evaluated in rats by using Morris water maze.MethodsMale Wistar rats were randomly divided into control, scopolamine and scopolamine plus glucosamine groups. All injections were given in 5 consecutive days and 30 min after each injection, the rats were tested in the Morris water maze test. Escape latency and path length to reach the hidden platform were subjected to analysis of variance [ANOVA].ResultsThe rats treated with scopolamine showed increased escape latency and path length to reach the hidden platform compared to control group (P < 0.001). Both escape latency and traveled path length to reach the hidden platform in glucosamine treated animals (1 and 2 g/kg) were significantly lower (P < 0.05 to P < 0.001) than in the scopolamine group.ConclusionThe results of this study showed that the glucosamine can inhibit scopolamine-induced impairments of spatial learning and memory in rats. Glucosamine might offer a promise in either the prevention or the treatment of neurodegenerative diseases such as Alzheimer's disease. 相似文献