Abstract:
:The state-dependent portion of cardio-vagal baroreflex control is called baroreflex hyteresis: we observe hysteresis when RR interval and carotid diameter depend on both the direction and value of arterial pressure. The elasticity of arterial walls, as well as the responsiveness of central command reset controls the real-time pattern of neural outflow, which is indirectly measured by RR interval in humans. We model the state-dependent relationship among pressure, vessel diameter and heart rate as a three-dimensional planar ellipse. Two-dimensional projections of this ellipse provide motion direction and quantify hysteresis between mechanical (pressure-diameter), neural (diameter-heart rate), and integrated baroreflex (pressure-heart rate) components. A convenient measure for the magnitude of hysteresis is the ratio of the semi-minor and semi-major axes of the best fitting ellipse. This ratio is given a sign according to the direction of its motion. The signed sum of the hysteresis ratio for vessel mechanics and central neural control reliably predicts cardio-vagal hysteresis. Using this relationship, we can quantify the relative importance of neural versus mechanical contributions to integrated baroreflex responses.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Ler AS,Cohen MA,Taylor JAdoi
10.1088/0967-3334/31/6/009subject
Has Abstractpub_date
2010-06-01 00:00:00pages
857-73issue
6eissn
0967-3334issn
1361-6579pii
S0967-3334(10)35897-7journal_volume
31pub_type
杂志文章abstract::We present the results of using electrical impedance tomographic spectroscopy (EITS) to follow the changes in lung water induced by oleic acid. Measurements were made on three goats before and after the injection of oleic acid. In addition to the EITs measurements, lung water was also measured using a double-indicator...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/17/4a/016
更新日期:1996-11-01 00:00:00
abstract::Linear methods of reconstruction play an important role in medical electrical impedance tomography (EIT) and there is a wide variety of algorithms based on several assumptions. With the Graz consensus reconstruction algorithm for EIT (GREIT), a novel linear reconstruction algorithm as well as a standardized framework ...
journal_title:Physiological measurement
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doi:10.1088/0967-3334/36/6/1161
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/8/011
更新日期:2007-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aa67b7
更新日期:2017-05-01 00:00:00
abstract::Temporal changes in the impedance spectra of bioelectrodes in contact with skin provide useful data for comparisons between differing electrode materials and skin preparation methods. Traditional impedance measuring systems employ swept frequency methods which will distort results in the impedance spectra of a sample ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/20/1/008
更新日期:1999-02-01 00:00:00
abstract::The main components responsible for the mechanical behavior of the arterial wall are collagen, elastin, and smooth muscle cells (SMCs) in the medial layer. We determined the structural and mechanical changes in porcine carotid arteries after administration of Triton® X-100, elastase, and collagenase using the inflatio...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/8/1335
更新日期:2012-08-01 00:00:00
abstract::The paper describes the development of an electrical impedance tomography (EIT) system for gynecologic research. The GIT (gynecological impedance tomography) system has 48 electrodes and is embedded on a small space (30 mm diameter and 20 mm height) inside of the vaginal probe. The system provides real-time (one shot ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/5/849
更新日期:2012-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab21af
更新日期:2019-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/8/1699
更新日期:2014-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/23/3/304
更新日期:2002-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/29/6/S29
更新日期:2008-06-01 00:00:00
abstract::Electrical impedance tomography (EIT) could be used as a portable non-invasive means to image the development of ischaemic stroke or haemorrhage. The purpose of this study was to examine if this was possible using time difference imaging, in the anesthetised rat using 40 spring-loaded scalp electrodes with applied con...
journal_title:Physiological measurement
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doi:10.1088/0967-3334/37/6/765
更新日期:2016-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/7/1439
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:10.1088/0967-3334/31/10/006
更新日期:2010-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/1/030
更新日期:2004-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/1361-6579/aab659
更新日期:2018-04-26 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/abdf3d
更新日期:2021-01-22 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/5/967
更新日期:2015-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:1996-05-01 00:00:00
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journal_title:Physiological measurement
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2011-04-01 00:00:00
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更新日期:2020-08-11 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2007-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2007-03-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/5/763
更新日期:2014-05-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2020-03-06 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2019-09-03 00:00:00
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journal_title:Physiological measurement
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更新日期:2015-01-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2003-02-01 00:00:00
abstract::Imaging photoplethysmography is a relatively new technique for extracting biometric information from video images of faces. This is useful in non-invasive monitoring of patients including neonates or the aged, with respect to sudden infant death syndrome, sleep apnoea, pulmonary disease, physical or mental stress and ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/1/67
更新日期:2015-01-01 00:00:00