Abstract:
:Nanostructured hydrogels have been developed as synthetic tissues and scaffolds for cell and drug delivery, and as guides for tissue regeneration. A fundamental problem in the development of synthetic hydrogels is that implanted gel structure is difficult to monitor noninvasively. This work demonstrates that the aggregation of magnetic nanoparticles, attached to specific macromolecules in biological and synthetic hydrogels, can be controlled to detect changes in gel macromolecular structure with MRI. It is further shown that the gels can be made to self-degrade when they come into contact with a target molecule in as low as pM concentrations. The sensitivity of the gels to the target is finely controlled using an embedded zymogen cascade amplifier. These "MRI reporter gels" may serve as smart, responsive polymer implants, as tissue scaffolds to deliver drugs, or to detect specific pathogens in vivo.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Colomb J,Louie K,Massia SP,Bennett KMdoi
10.1002/mrm.22570subject
Has Abstractpub_date
2010-12-01 00:00:00pages
1792-9issue
6eissn
0740-3194issn
1522-2594journal_volume
64pub_type
杂志文章abstract::Intra-plaque hemorrhage (IPH) and lipid core, characteristics of rupture prone carotid plaques, are often visualized in vivo with MRI using T1 weighted gradient and spin echo, respectively. Increasing magnetic field strength may help to identify IPH and lipid core better. As a proof of concept, automatic segmentation ...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.23191
更新日期:2012-06-01 00:00:00
abstract::If magnetic resonance spectroscopy (MRS) is to become a useful tool in clinical medicine, it will be necessary to find reliable methods for analyzing and classifying MRS data. Automated methods are desirable because they can remove user bias and can deal with large amounts of data, allowing the use of all the availabl...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910350608
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journal_title:Magnetic resonance in medicine
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abstract:PURPOSE:To establish a series of relationships defining how muscle microstructure and diffusion tensor imaging (DTI) are related. METHODS:The relationship among key microstructural features of skeletal muscle (fiber size, fibrosis, edema, and permeability) and the diffusion tensor were systematically simulated over ph...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26993
更新日期:2018-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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abstract::19F NMR imaging of the perfluorocarbon emulsion Fluosol has been used to study regional variations in oxygen tension in rat liver and spleen. We have used the linear dependence of spin lattice relaxation rate (1/T1) on the partial oxygen pressure (pO2) of Fluosol to determine the oxygen tension in the reticuloendothel...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910290405
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journal_title:Magnetic resonance in medicine
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更新日期:2021-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.22966
更新日期:2011-12-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910170208
更新日期:1991-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2021-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.22044
更新日期:2009-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910270204
更新日期:1992-10-01 00:00:00
abstract:PURPOSE:To model and correct the dephasing effects in the gradient-echo signal for arbitrary RF excitation pulses with large flip angles in the presence of macroscopic field variations. METHODS:The dephasing of the spoiled 2D gradient-echo signal was modeled using a numerical solution of the Bloch equations to calcula...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.28139
更新日期:2020-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910290307
更新日期:1993-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1122
更新日期:2001-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.21122
更新日期:2007-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22090
更新日期:2009-10-01 00:00:00
abstract::A technique for reconstructing dynamic undersampled MRI data, termed "x-f choice," was developed and applied to dynamic contrast-enhanced MR angiography (DCE-MRA). Regular undersampling in k-t space (a hybrid of k-space and time) creates aliasing in the conjugate x-f space that must be resolved. When regions in the ob...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21008
更新日期:2006-10-01 00:00:00
abstract::Longitudinal P-31 relaxation rate enhancements of phosphate groups have been measured at pH 7-7.2 and 310 degrees K on aqueous solutions containing adenosine triphosphate (ATP), phosphocreatine (PCr), inorganic phosphate (Pi) and some lanthanide complexes (Gd-DOTA, Gd-HPDO3A, Gd-DO3A, Gd-DTPA, Gd-DTPA-BMA). The macroc...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910310413
更新日期:1994-04-01 00:00:00
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更新日期:2020-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2012-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910310403
更新日期:1994-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910070211
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910090114
更新日期:1989-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910370417
更新日期:1997-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910390421
更新日期:1998-04-01 00:00:00
abstract::MR techniques have proven their ability to investigate skeletal muscle function in situ. Their benefit in terms of noninvasiveness is, however, lost in animal research, given that muscle stimulation and force output measurements are usually achieved using invasive surgical procedures, thereby excluding repeated invest...
journal_title:Magnetic resonance in medicine
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更新日期:2010-07-01 00:00:00
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更新日期:2006-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.25653
更新日期:2016-01-01 00:00:00