Abstract:
:Use of conjugated equine estrogens (CEE) has been linked to smaller regional brain volumes in women aged ≥65 years; however, it is unknown whether this results in a broad-based characteristic pattern of effects. Structural magnetic resonance imaging was used to assess regional volumes of normal tissue and ischemic lesions among 513 women who had been enrolled in a randomized clinical trial of CEE therapy for an average of 6.6 years, beginning at ages 65-80 years. A multivariate pattern analysis, based on a machine learning technique that combined Random Forest and logistic regression with L(1) penalty, was applied to identify patterns among regional volumes associated with therapy and whether patterns discriminate between treatment groups. The multivariate pattern analysis detected smaller regional volumes of normal tissue within the limbic and temporal lobes among women that had been assigned to CEE therapy. Mean decrements ranged as high as 7% in the left entorhinal cortex and 5% in the left perirhinal cortex, which exceeded the effect sizes reported previously in frontal lobe and hippocampus. Overall accuracy of classification based on these patterns, however, was projected to be only 54.5%. Prescription of CEE therapy for an average of 6.6 years is associated with lower regional brain volumes, but it does not induce a characteristic spatial pattern of changes in brain volumes of sufficient magnitude to discriminate users and nonusers.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Casanova R,Espeland MA,Goveas JS,Davatzikos C,Gaussoin SA,Maldjian JA,Brunner RL,Kuller LH,Johnson KC,Mysiw WJ,Wagner B,Resnick SM,Women's Health Initiative Memory Study.doi
10.1016/j.mri.2010.12.001subject
Has Abstractpub_date
2011-05-01 00:00:00pages
546-53issue
4eissn
0730-725Xissn
1873-5894pii
S0730-725X(10)00394-2journal_volume
29pub_type
杂志文章,随机对照试验abstract::Balanced steady-state free precession (SSFP) sequences use fully re-focussed gradient waveforms to achieve a high signal and useful image contrast in short scan times. Despite these strengths, the clinical feasibility of balanced SSFP is still limited both by bright fat signal and by the signal voids that result from ...
journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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journal_title:Magnetic resonance imaging
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更新日期:2014-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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更新日期:2008-10-01 00:00:00
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更新日期:2003-04-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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更新日期:2020-07-01 00:00:00
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journal_title:Magnetic resonance imaging
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更新日期:2018-06-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90011-n
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.02.020
更新日期:2008-11-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(88)90125-7
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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更新日期:2005-02-01 00:00:00
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journal_title:Magnetic resonance imaging
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doi:10.1016/j.mri.2016.08.006
更新日期:2017-01-01 00:00:00
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
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abstract::The density driven convection phenomenon is expected to have a significant and positive role in CO2 geological storage capacity and safety. The onset and development of density-driven convective on the core scale is critical to understand the mass transfer mechanism. In this paper, laboratory experiments were conducte...
journal_title:Magnetic resonance imaging
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更新日期:2017-06-01 00:00:00
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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更新日期:2018-12-01 00:00:00
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journal_title:Magnetic resonance imaging
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pub_type: 杂志文章
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