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991.
Syed A. Agha MD Andreas P. Kalogeropoulos MD Jeffrey Shih MD Vasiliki V. Georgiopoulou MD Grigorios Giamouzis MD PhD Perry Anarado MD Deepa Mangalat MD Imad Hussain MD Wendy Book MD Sonjoy Laskar MD Andrew L. Smith MD Randolph Martin MD Javed Butler MD MPH 《Journal of cardiac failure》2009,15(7):586-592
BackgroundIncremental value of echocardiography over clinical parameters for outcome prediction in advanced heart failure (HF) is not well established.Methods and ResultsWe evaluated 223 patients with advanced HF receiving optimal therapy (91.9% angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, 92.8% β-blockers, 71.8% biventricular pacemaker, and/or defibrillator use). The Seattle Heart Failure Model (SHFM) was used as the reference clinical risk prediction scheme. The incremental value of echocardiographic parameters for event prediction (death or urgent heart transplantation) was measured by the improvement in fit and discrimination achieved by addition of standard echocardiographic parameters to the SHFM. After a median follow-up of 2.4 years, there were 38 (17.0%) events (35 deaths; 3 urgent transplants). The SHFM had likelihood ratio (LR) χ2 32.0 and C statistic 0.756 for event prediction. Left ventricular end-systolic volume, stroke volume, and severe tricuspid regurgitation were independent echocardiographic predictors of events. The addition of these parameters to SHFM improved LR χ2 to 72.0 and C statistic to 0.866 (P < .001 and P = .019, respectively). Reclassifying the SHFM-predicted risk with use of the echocardiography-added model resulted in improved prognostic separation.ConclusionsAddition of standard echocardiographic variables to the SHFM results in significant improvement in risk prediction for patients with advanced HF. 相似文献
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Steven R. Barthel Georg K. Wiese Jaehyung Cho Matthew J. Opperman Danielle L. Hays Javed Siddiqui Kenneth J. Pienta Bruce Furie Charles J. Dimitroff 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(46):19491-19496
How cancer cells bind to vascular surfaces and extravasate into target organs is an underappreciated, yet essential step in metastasis. We postulate that the metastatic process involves discrete adhesive interactions between circulating cancer cells and microvascular endothelial cells. Sialyl Lewis X (sLeX) on prostate cancer (PCa) cells is thought to promote metastasis by mediating PCa cell binding to microvascular endothelial (E)-selectin. Yet, regulation of sLeX and related E-selectin ligand expression in PCa cells is a poorly understood factor in PCa metastasis. Here, we describe a glycobiological mechanism regulating E-selectin-mediated adhesion and metastatic potential of PCa cells. We demonstrate that α1,3 fucosyltransferases (FT) 3, 6, and 7 are markedly elevated in bone- and liver-metastatic PCa and dictate synthesis of sLeX and E-selectin ligands on metastatic PCa cells. Upregulated FT3, FT6, or FT7 expression induced robust PCa PC-3 cell adhesion to bone marrow (BM) endothelium and to inflamed postcapillary venules in an E-selectin-dependent manner. Membrane proteins, CD44, carcinoembryonic antigen (CEA), podocalyxin-like protein (PCLP), and melanoma cell adhesion molecule (MCAM) were major scaffolds presenting E-selectin-binding determinants on FT-upregulated PC-3 cells. Furthermore, elevated FT7 expression promoted PC-3 cell trafficking to and retention in BM through an E-selectin dependent event. These results indicate that α1,3 FTs could enhance metastatic efficiency of PCa by triggering an E-selectin-dependent trafficking mechanism. 相似文献
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Epiretinal membrane is occasionally encountered in children; it is usually idiopathic but can be due to conditions such as vitreous hemorrhage or shaken baby syndrome. Though persistent adherence of the symptomatic epiretinal membrane warrants surgical intervention, spontaneous separation of the membrane has been reported. We report a case of spontaneous separation of an idiopathic epiretinal membrane in a young child. 相似文献
999.
Seventeen patients with petroelival and foramen magnum meningiomas encasing the vertebral or basilar arteries and their branches were surgically excised over a 3-year period. All six cases with vertebral artery encasement were totally excised. One vertebral artery was occluded, one was repaired, and one was replaced with a vein graft. None of the patients had a permanent major neurologic deficit. In one patient with vertebral and basilar artery encasement, a hypoplastic vertebral artery was occluded and the tumor was totally excised. She had a transient worsening of hemiparesis, presumably due to the dissection of tumor from the brainstem. Among the ten patients with encasement of the basilar artery and branches, injury to the basilar artery occurred in two patients, both were repaired. Injuries to one superior cerebellar artery, one anterior inferior cerebellar artery, and one perforating vessel could not be repaired. Three patients sustained major neurologic deficits, but only in two did this result in permanent functional deterioration. Three of the ten patients had a gross total resection, five had subtotal resection (90% or more of tumor volume), and two had resection of 70% of the tumor volume. Eight patients had improvement in their Karnofsky scores. None showed recurrence or regrowth on follow-up ranging from 2 to 6 years. Greater difficulty with dissection was experienced in previously operated patients, and in patients who did not have an arachnoid plane between the brainstem and the tumor. Magnetic resonance imaging was the most useful preoperative test. It is concluded that meningiomas with vertebrobasilar artery encasement can be removed successfully with modern skull base surgery techniques. The surgeon needs to exercise caution and judgment in deciding how far the removal of these lesions should be pursued. 相似文献
1000.
Haytham F. Isleem Muhammad Abid Wesam Salah Alaloul Muhammad Kamal Shah Shayan Zeb Muhammad Ali Musarat Muhammad Faisal Javed Fahid Aslam Hisham Alabduljabbar 《Materials》2021,14(13)
The majority of experimental and analytical studies on fiber-reinforced polymer (FRP) confined concrete has largely concentrated on plain (unreinforced) small-scale concrete columns, on which the efficiency of strengthening is much higher compared with large-scale columns. Although reinforced concrete (RC) columns subjected to combined axial compression and flexural loads (i.e., eccentric compression) are the most common structural elements used in practice, research on eccentrically-loaded FRP-confined rectangular RC columns has been much more limited. More specifically, the limited research has generally been concerned with small-scale RC columns, and hence, the proposed eccentric-loading stress-strain models were mainly based on the existing concentric-loading models of FRP-confined concrete columns of small scale. In the light of such demand to date, this paper is aimed at developing a mathematical model to better predict the strength of FRP-confined rectangular RC columns. The strain distribution of FRP around the circumference of the rectangular sections was investigated to propose equations for the actual rupture strain of FRP wrapped in the horizontal and vertical directions. The model was accomplished using 230 results of 155 tested specimens compiled from 19 studies available in the technical literature. The test database covers an unconfined concrete strength ranging between 9.9 and 73.1 MPa, and section’s dimension ranging from 100–300 mm and 125–435 mm for the short and long sides, respectively. Other test parameters, such as aspect ratio, corner radius, internal hoop steel reinforcement, FRP wrapping layout, and number of FRP wraps were all considered in the model. The performance of the model shows a very good correlation with the test results. 相似文献