Abstract:
:A magnetic pulse generator has been set up in order to study gastric activity. Two coils 1.05 m in diameter, arranged in a Helmholtz configuration, were used. The system generated magnetic field pulses higher than 15 mT, of duration 17.3+/-1.2 ms. Measurements were performed in 11 male volunteers, with average age 29.3+/-6.4 years and body mass index 26.0+/-4.8 kg m(-2). Magnetite (Fe3O4) particles with diameters from 75 to 125 microm were used as magnetic tracers, which were mixed in 250 ml of yogurt in concentrations from 2 to 5 g. Signals were registered by using a high speed 3 axis fluxgate digital magnetometer and processed to determine the relaxation of the magnetic tracers by fitting a first-order exponential function to the data, a mean relaxation constant K = 116+/-40 s(-1) was obtained. Also, an average gastric peristaltic frequency was measured; a value of 3.2+/-0.3 cpm was determined.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Cordova-Fraga T,Bernal-Alvarado JJ,Gutierrez-Juarez G,Sosa M,Vargas-Luna Mdoi
10.1088/0967-3334/25/5/015subject
Has Abstractpub_date
2004-10-01 00:00:00pages
1261-70issue
5eissn
0967-3334issn
1361-6579journal_volume
25pub_type
临床试验,杂志文章abstract::Focused impedance measurements (FIM) are used in several fields, and address the problem of measuring the volume impedance of an object within a volume conductor. Several electrode configurations are possible, and these have different properties. Sensitivity fields of four configurations have been investigated. We pre...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/6/1067
更新日期:2014-06-01 00:00:00
abstract::The purpose of this study was to examine the validity and reliability of estimated parameters of the work-time relationship during cross-country ski ergometry using the traditional multi-trial critical power (CP) test and a 3 min 'all-out' test (3MT). Fourteen recreationally active male participants (mean ± SD; age: 2...
journal_title:Physiological measurement
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doi:10.1088/0967-3334/35/1/31
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abstract::Wearables such as accelerometers are emerging as powerful tools for quantifying gait in various environments. Flexibility in wearable location may improve ease of use and data acquisition during instrumented testing. However, change of location may impact algorithm functionality when evaluating associated gait charact...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/10/1785
更新日期:2016-10-01 00:00:00
abstract:OBJECTIVE:Increased penetration of pulsatile power to the brain has been implicated in the pathogenesis of age-related cognitive dysfunction and dementia, a common comorbidity in patients with heart failure and preserved ejection fraction (HFpEF). However, there is a lack of knowledge on the effects of organic and inor...
journal_title:Physiological measurement
pub_type: 杂志文章,随机对照试验
doi:10.1088/1361-6579/aab2ef
更新日期:2018-04-20 00:00:00
abstract:OBJECTIVE:In this paper, a support vector machine (SVM) approach using statistical features, P wave absence, spectrum features, and length-adaptive entropy are presented to classify ECG rhythms as four types: normal rhythm, atrial fibrillation (AF), other rhythm, and too noisy to classify. APPROACH:The proposed algori...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aac7aa
更新日期:2018-06-25 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/9/007
更新日期:2006-09-01 00:00:00
abstract::In this study, we developed a novel technique for estimating non-constrained and cuffless blood pressure (BP) that was based on electrocardiogram (ECG) and ballistocardiogram (BCG). The BCG was non-invasively measured using a common electronic weighing scale when a subject was standing on it. The ECG was measured usin...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/30/7/011
更新日期:2009-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/23/1/316
更新日期:2002-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab921d
更新日期:2020-06-30 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/4/007
更新日期:1993-11-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/2/002
更新日期:2008-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/009
更新日期:1993-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab6ebb
更新日期:2020-03-06 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/8/S06
更新日期:2010-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/1/83
更新日期:2016-01-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aba80f
更新日期:2020-09-04 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaee19
更新日期:2018-12-07 00:00:00
abstract::Electrical impedance tomography (EIT) measures the conductivity distribution within an object based on the current applied and voltage measured at surface electrodes. Thus, EIT images are sensitive to electrode properties (i.e. contact impedance, electrode area and boundary shape under the electrode). While some of th...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/7/S02
更新日期:2011-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/7/1349
更新日期:2014-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/6/007
更新日期:2004-12-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/16/4/003
更新日期:1995-11-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/24/2/357
更新日期:2003-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/10/2135
更新日期:2014-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab840a
更新日期:2020-05-07 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/21/2/303
更新日期:2000-05-01 00:00:00
abstract::Electrical impedance tomography (EIT) is very sensitive to deformations of the medium boundary shape. For lung imaging, breathing and changes in posture move the electrodes and change the chest shape, resulting in image artefacts. Several approaches have been proposed to improve the reconstructed images; most methods ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/6/S08
更新日期:2008-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab9b67
更新日期:2020-08-11 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaa749
更新日期:2018-03-23 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/3/010
更新日期:2005-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/1/004
更新日期:1994-02-01 00:00:00