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121.
Juliano L. Fernandes Matheus A. Silveira Kleber Fertrin Samira Lauar Andre Fattori Otavio Coelho Flavia Pegado Junqueira Guilherme Moura da Cunha Antonio Carlos Coutinho Jr. Fabricio B. Pereira Monica Verissimo Sara T. Saad 《Annals of hematology》2012,91(12):1839-1844
Thalassemia major (TM) patients have altered ventricular volumes and ejection fraction compared to normals, although evidence for these findings stem from restricted patient groups and has never been reproduced. We sought to evaluate cardiac parameters by cardiovascular magnetic resonance (CMR) in a group of young TM patients not covered by previous studies that are more representative of the TM population in many countries. Seventy patients including 40 TM with normal myocardial iron concentrations, and 30 age- and gender-matched normal (NL) volunteers underwent a CMR study for assessment of left and right ventricle volumes and function using a 1.5-T scanner. Left and right ventricle ejection fraction, indexed systolic and diastolic volumes, and indexed mass were compared between the two groups. Mean age of TM patients was 18.2?±?7.1 versus 17.5?±?8.5?years in NL with no significant differences (P?=?0.73). There was no difference in left ventricular (LV) ejection fraction between the groups (TM 64.9?±?5.7?%, NL 64.9?±?5.2?%; P?=?0.97). LV normalized end-diastolic and end-systolic volumes were significantly higher in patients with TM compared to NL volunteers (76.8?±?19.4 versus 66.6?±?11.7?mL/m2, P?=?0.008, and 27.0?±?8.8 versus 23.6?±?5.0?mL/m2, P?=?0.045). LV indexed mass was also higher in TM patients compared to NL (51.2?±?11.9 versus 42.0?±?8.5?g/m2, P?<?0.001). No significant differences were observed in right ventricular parameters. In conclusion, younger patients with TM do not present different left or right ventricular function values compared to normal controls despite having increased left ventricular volumes and mass. 相似文献
122.
OPINION STATEMENT: Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide, and it is associated with an elevated risk of thromboembolic events, including ischemic stroke. Evidence suggests that at least 90?% of left atrial thrombi discovered in patients with AF are localized to the left atrial appendage (LAA). Surgical ligation or excision of the LAA is considered the standard of care in patients who undergo mitral valve surgery or as an adjunct to a surgical Maze procedure for treatment of AF. In addition, in selected patients with AF and an elevated risk of thromboembolic events, particularly in those with contraindication to oral anticoagulation (OAC) therapy, it is reasonable to consider LAA exclusion to offer protection against ischemic stroke and other embolic complications. This can be achieved through a number of different strategies, including surgical amputation or ligation of the LAA, percutaneous endocardial occlusion of the LAA by deployment of occlusive devices, and also ligation of the LAA via a closed-chest, percutaneous, epicardial catheter-based approach in select patients. Although results from several recent percutaneous LAA closure and ligation studies are highly promising, the evidence for long-term efficacy and safety is insufficient to presently recommend this approach to all patients other than those in whom long-term OAC is contraindicated. Future randomized studies are required to further address the long-term safety and efficacy of these therapeutic options. Finally, the role for LAA occlusion and ligation seems less clear in patients who undergo successful catheter ablation of AF, since at least in a subgroup of these patients antiplatelet therapy alone has been shown to be sufficient. 相似文献
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Adrian S. Fairey Wassim Kassouf Eric Estey Simon Tanguay Ricardo Rendon David Bell Jonathan Izawa Joseph Chin Anil Kapoor Edward Matsumoto Peter Black Alan So Jean‐Baptiste Lattouf Fred Saad Darrel Drachenberg Ilias Cagiannos Louis Lacombe Yves Fradet Niels‐Erik B. Jacobsen 《BJU international》2013,112(6):791-797
127.
The presubiculum (PrS) plays critical roles in spatial information processing and memory consolidation and has also been implicated in temporal lobe epileptogenesis. Despite its involvement in these processes, a basic structure–function analysis of PrS cells remains far from complete. To this end, we performed whole‐cell recording and biocytin labeling of PrS neurons in layer (L)II and LIII to examine their electrophysiological and morphological properties. We characterized the cell types based on electrophysiological criteria, correlated their gross morphology, and classified them into distinct categories using unsupervised hierarchical cluster analysis. We identified seven distinct cell types: regular‐spiking (RS), irregular‐spiking (IR), initially bursting (IB), stuttering (Stu), single‐spiking (SS), fast‐adapting (FA), and late‐spiking (LS) cells, of which RS and IB cells were common to LII and LIII, LS cells were specific to LIII, and the remaining types were identified exclusively in LII. Recorded neurons were either pyramidal or nonpyramidal and, except for Stu cells, displayed spine‐rich dendrites. The RS, IB, and IR cells appeared to be projection neurons based on extension of their axons into LIII of the medial entorhinal area (MEA) and/or angular bundle. We conclude that LII and LIII of PrS are distinct in their neuronal populations and together constitute a more diverse population of neurons than previously suggested. PrS neurons serve as major drivers of circuits in superficial (LII–III) entorhinal cortex (ERC) and couple neighboring structures through robust afferentation, thereby substantiating the PrS's critical role in the parahippocampal region. J. Comp. Neurol. 521: 3116–3132, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
128.
During cancer treatment, doses must be carefully administered and monitored to guarantee efficacy and minimize side-effects. A potentiometric sensor was developed for the direct real-time assay of a widely used antineoplastic drug (vinblastine (VB)) in plasma samples. Membrane cocktails were drop-casted over a glassy-carbon electrode coated with a lipophilic conducting polymer (polyaniline). The study investigated five cation exchangers, five plasticizers (of different polarities and dielectric constants), and four ionophores with different physicochemical characters on the sensor performance. The study substantiates a data-driven selection of the optimum membrane recipe. The latter included sodium tetraphenylborate as an ion exchanger, dioctylphthalate as a plasticizer, and hydroxypropyl-β-cyclodextrin as ionophore. The membrane proved a near-Nernstian slope of 37.5 mV per decade, a LOQ of 2.99 × 10−6 M, and a stable fast response. The selectivity study proved poor responses to common physiological ions. The developed sensor was used for the determination of VB in its pure powder form, marketed formulation, and plasma samples. The fast and direct sensor response enables a wide range of applications in quality control laboratories and clinical studies.Potentiometric glassy carbon electrode for determination of vinblastine. 相似文献
129.
William M. Sherk Minhaj S. Khaja Bill S. Majdalany Wael E. Saad Aaron M. Udager Kyle J. Cooper David M. Williams 《Journal of vascular and interventional radiology : JVIR》2019,30(1):54-60
Between September 2008 and August 2017, 36 patients (mean age 56 y; range, 30–89 y) underwent transvenous biopsy of suspected tumor thrombus or perivascular tumor. Intravascular biopsy was pursued because of inaccessible percutaneous access in 9 patients (25%) and as part of a planned revascularization procedure in 27 patients (75%). Histopathologic results showed malignancy in 26 patients (72%) and benign etiologies in 10 patients (28%). No patients required repeat biopsy. There were no complications related to the biopsy procedure. The present series suggests that transvenous biopsy is a safe and accurate method of intravascular and perivascular mass tissue sampling. 相似文献