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41.
Recent advances in MRI have made this modality an important tool for evaluating heart disease. Faster scanning techniques, high spatial resolution, lack of ionizing radiation, lack of dependence on contrast material, and capability for functional imaging have made it an emerging noninvasive diagnostic tool with great potential in younger patients with heart disease. This article discusses the role of cardiac MRI, methods of evaluation, and newer application of MRI in evaluating congenital heart disease in pediatric and young adult patients.  相似文献   
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Bhalla  K; Holladay  C; Arlin  Z; Grant  S; Ibrado  AM; Jasiok  M 《Blood》1991,78(10):2674-2679
Hematopoietic growth factors (HGFs) interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) individually have been shown to increase the percentage of acute myeloid leukemia (AML) blasts in S phase and enhance the cytotoxic effects of Ara-C against these blasts in culture. We compared in vitro the effects of a combined treatment with GM-CSF (10 ng/mL) plus IL-3 (10 ng/mL) on the metabolism and cytotoxicity of Ara-C in normal bone marrow mononuclear cells (NBMMC) and AML blasts. NBMMC from six healthy volunteers and AML blasts from 10 patients were incubated for 20 hours with or without IL- 3 plus GM-CSF, followed by a concurrent treatment with Ara-C for 4 additional hours. Exposure to the HGFs and Ara-C produced significantly higher intracellular Ara-CTP levels as well as higher Ara-CTP/dCTP pool ratios in AML blasts as compared with NBMMC. Treatment with HGFs resulted in [3H] Ara-C DNA incorporation that was significantly higher in AML blasts versus NBMMC. This selective improvement of Ara-C metabolism in AML blasts was associated with an enhanced Ara-C-mediated leukemia colony-forming unit (CFU) growth inhibition. In contrast, exposure to HGFs resulted in an improved colony growth of normal CFU granulocyte-monocyte and CFU-granulocyte, erythroid, monocyte, megakaryocyte. These in vitro studies indicate that a combined treatment with IL-3 plus GM-CSF may improve the selectivity of Ara-C against AML blasts.  相似文献   
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Overactivation of mineralocorticoid receptor pathways has been implicated in the pathophysiology of central serous chorioretinopathy (CSCR). Recently, mineralocorticoid receptor antagonists such as eplerenone have demonstrated success in treating subretinal fluid in CSCR. This case demonstrates a patient who was initially presumed to have subretinal fluid secondary to CSCR and was started on a trial of oral eplerenone. It quickly became evident that her subretinal fluid was secondary to a peripapillary polypoidal choroidal vasculopathy network, but she demonstrated a significant improvement with oral eplerenone. To the authors'' knowledge, this is the first case of eplerenone use to treat polypoidal choroidal vasculopathy.Key Words: Eplerenone, Mineralocorticoid antagonist, Polypoidal choroidal vasculopathy  相似文献   
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Journal of Interventional Cardiac Electrophysiology - Atrial fibrillation is associated with an increased risk of cognitive impairment. It is unclear whether the restoration of sinus rhythm with...  相似文献   
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OBJECTIVES: The purpose of the present study was to assess whether preoperative and postoperative B-type natriuretic peptide (BNP) levels could be used as predictors of postoperative complications and outcomes in patients after open-heart surgery. BACKGROUND: A variety of multifactor indexes have been proposed for preoperative risk assessment of patients undergoing cardiac surgery, but they have shown limited ability and utility in accurately predicting postoperative complications, hospital stay, and mortality. METHODS: Subjects consisted of 98 male patients (63 +/- 9.1 years) undergoing open-heart surgery at the San Diego Veterans Administration Health System during a 19-month period. B-type natriuretic peptide levels were analyzed, and postoperative data recorded. RESULTS: There was a higher preoperative BNP level in patients requiring the use of intra-aortic balloon pumps (IABPs) (mean BNP = 387 +/- 112 pg/ml vs. 181 +/- 25 pg/ml), in patients who died within one year (357 +/- 93 pg/ml vs. 184 +/- 26 pg/ml), and in patients with postoperative hospital stays of 10 days or more (307 +/- 68 pg/ml vs. 179 +/- 27 pg/ml). Receiver operating characteristic curves demonstrated preoperative BNP levels as predictors of postoperative IABP use, hospital stay 385 pg/ml predict the postoperative complications and one-year mortality after heart surgery. Postoperatively, elevated peak BNP levels and elevated change to peak BNP levels were associated with prolonged hospital stay and mortality within one year.  相似文献   
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OBJECTIVES: We investigated the antiarrhythmic effects of intrapericardial nitroglycerin (NTG) during acute myocardial ischemia in the porcine heart. BACKGROUND: Nitroglycerin is a nitric oxide donor that exerts potent effects on the cardiovascular system. Intrapericardial administration allows investigation of pharmacologic actions on cardiac tissue in an in vivo system while minimizing the confounding influences of systemic effects. METHODS: In 29 closed-chest pigs, myocardial ischemia was induced by intraluminal balloon occlusion of the left anterior descending coronary artery. Arrhythmia incidence was monitored during 5-min balloon inflations performed without drug and at 15, 45, 75, and 105 min after NTG (4,000 microg bolus) administered by percutaneous transatrial access into the pericardial space. Electrocardiograms were monitored for ischemia-induced T-wave alternans (TWA), a marker of electrical instability. The antiadrenergic potential of NTG was investigated by examining the drug's suppression of dobutamine-induced increase in myocardial contractility. RESULTS: Control coronary artery occlusion provoked ventricular fibrillation (VF) in all animals. Intrapericardial NTG suppressed VF at 45 min in all six pigs (p < 0.05) and reduced TWA across a parallel time course (from 459.1 +/- 144.4 microV before drug to 42.22 +/- 13.96 microV at 45 min, p = 0.047). The antifibrillatory effect occurred as early as 15 min and persisted for up to 75 min. Augmentation of maximum of the first time derivative of left ventricular pressure by dobutamine was blunted by intrapericardial NTG (from 3,999 +/- 196 mm Hg/s before NTG to 3,543 +/- 220 mm Hg/s at 15 min, p = 0.012). CONCLUSIONS: Intrapericardial NTG exerts a robust antifibrillatory action. Potential mechanisms include reduction in electrical instability and blunting of adrenergic effects.  相似文献   
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Manchanda  Smita  Semalti  Kapil  Bhalla  Ashu Seith  Thakar  Alok  Sikka  Kapil  Verma  Hitesh 《Emergency radiology》2021,28(6):1063-1072
Emergency Radiology - COVID-19 patients have been found to have an increased incidence of superadded fungal infections because of multiple factors such as impaired cell-mediated immunity,...  相似文献   
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