Abstract:
:Electrical impedance spectroscopy has been developed as a potential method for the diagnosis of carcinoma in epithelial tissues. An understanding of the influence of structural changes in the tissue on the properties measured using this technique is essential for interpreting measured data and optimization of probe design. In contrast to other tissue types, carcinoma in situ of the bladder gives rise to an increase in electrical impedance over the kHz-MHz frequency range in comparison to normal tissue. Finite element models of the urothelium and the underlying superficial lamina propria have been constructed and solved in order to ascertain the influence of structural changes associated with malignancy, oedema and inflammation on the measured electrical properties of the tissue. Sensitivity analysis of results from a composite tissue model suggests that the increase in lymphocyte density in the lamina propria associated with an inflammatory response to the infiltration of urine into the tissue may explain these unusual electrical properties.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Walker DC,Smallwood RH,Keshtar A,Wilkinson BA,Hamdy FC,Lee JAdoi
10.1088/0967-3334/26/3/010subject
Has Abstractpub_date
2005-06-01 00:00:00pages
251-68issue
3eissn
0967-3334issn
1361-6579pii
S0967-3334(05)90932-5journal_volume
26pub_type
杂志文章abstract::Fluorine (F) plays an important role in dental health and bone formation. Many studies have shown that excess fluoride (F(-)) can result in dental or skeletal fluorosis, while other studies have indicated that a proper dosage of fluoride may have a protective effect on bone fracture incidence. Fluorine is stored almos...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/33/2/243
更新日期:2012-02-01 00:00:00
abstract::The use of artificial neural networks (ANNs) to interpret sleep monitoring signals is described. Recordings from ten infants with apparent life threatening episodes were assigned into training feedforward R-PROP networks. In order to separate good signal from artefact, 60 second time frames of SaO2 and TcPO2 signals w...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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abstract::Spirometry is the gold standard to determine the presence of airflow obstruction, but it requires volitional participation and needs qualified supervision. The forced oscillation technique (FOT) measures respiratory input impedance (Zrs) during spontaneous breathing and it could be useful for unsupervised monitoring o...
journal_title:Physiological measurement
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doi:10.1088/0967-3334/31/4/N01
更新日期:2010-04-01 00:00:00
abstract::Unstable gait is a risk factor for falls. Wearable accelerometers enable remote monitoring of daily walking. Here, new methods for measuring stride-to-stride oscillations are validated against optical motion capture, normative data determined, and dependency on walking speed investigated. Walks by 13 young people (mea...
journal_title:Physiological measurement
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journal_title:Physiological measurement
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doi:10.1088/1361-6579/aab7ac
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:10.1088/0967-3334/26/4/001
更新日期:2005-08-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2009-03-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/25/5/015
更新日期:2004-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/7/S10
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:10.1088/1361-6579/aa9047
更新日期:2017-10-31 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章,评审
doi:10.1088/0967-3334/37/9/R73
更新日期:2016-09-01 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
abstract::The measurement of the complex respiratory impedance at a high temporal resolution is described. The measurement of impedance is correlated with the breathing cycle using electrical transthoracic impedance. This allows the determination of the complex impedance at any fixed point in the respiratory cycle, which result...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/019
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:10.1088/0967-3334/16/3a/009
更新日期:1995-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/1361-6579/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/aae42e
更新日期:2018-10-30 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/3/L1
更新日期:2016-03-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/34/11/1483
更新日期:2013-11-01 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
abstract::Monitoring the brain state in anaesthesia is crucial for clinical doctors. In this study, we propose a novel nonlinear method, the permutation Lempel-Ziv complexity (PLZC) index, which describes the complexity in the electroencephalographic (EEG) signal to quantify the effect of GABAergic anaesthetics on brain activit...
journal_title:Physiological measurement
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journal_title:Physiological measurement
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doi:10.1088/0967-3334/36/8/1665
更新日期:2015-08-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2008-08-01 00:00:00
abstract::The results of a preliminary clinical evaluation of a one-frequency electrical impedance tomography (EIT) system enabling static in vivo imaging are presented. The design of the measuring system and image reconstruction software are described. Thirty-one subjects were examined and divided into four clinical groups. Th...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2002-02-01 00:00:00
abstract::A simple wearable device for sit-to-stand timing detection was designed and constructed with rate gyroscopes and accelerometers and a dedicated adaptive algorithm. The method was validated by comparison with optoelectronic equipment. Results from the comparison showed a maximal error always lower than 2.5 x 10(-2) s f...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/8/006
更新日期:2006-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/22/1/308
更新日期:2001-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/11/010
更新日期:2006-11-01 00:00:00
abstract::Non-invasive fetal heart rate is of great relevance in clinical practice to monitor fetal health state during pregnancy. To date, however, despite significant advances in the field of electrocardiography, the analysis of abdominal fetal ECG is considered a challenging problem for biomedical and signal processing commu...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/8/1607
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:10.1088/0967-3334/15/3/010
更新日期:1994-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/18/1/007
更新日期:1997-02-01 00:00:00
abstract::Non-contact heart and lung activity monitoring would be a desirable supplement to conventional monitoring techniques. Based on the potential of non-contact magnetic induction measurements, requirements for an adequate monitoring system were estimated. This formed the basis for the development of the presented extendab...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/6/S25
更新日期:2008-06-01 00:00:00