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::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
abstract::Obesity is associated with abnormal cardiac regulation by the autonomic nervous system (ANS), this being reversed by weight loss. Bariatric (weight-reduction) surgery can induce substantial long-term weight reductions. This study compares the acute influence on ANS control of two different types of bariatric surgery i...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/30/7/002
更新日期:2009-07-01 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
abstract:OBJECTIVE:Transfer function analysis (TFA) of dynamic cerebral autoregulation (dCA) requires smoothing of spectral estimates using segmentation of the data (SD). Systematic studies are required to elucidate the potential influence of SD on dCA parameters. APPROACH:Healthy subjects (HS, n = 237) and acute ischaemic str...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab7ddf
更新日期:2020-04-17 00:00:00
abstract::In recent AASM practice, parameter actimetry is cited to measure total sleep time in obstructive sleep apnoea patients, when polysomnography is not available. An actigraph was therefore compared to polysomnographic data in 28 subjects with known sleep disordered breathing. Total sleep time (TST), sleep period time (SP...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/12/005
更新日期:2010-12-01 00:00:00
abstract::The left atrium (LA) plays an important role in the maintenance of hemodynamic and electrical stability of the heart. One of the conditions altering the atrial mechanical function is atrial fibrillation (AF), leading to an increased thromboembolic risk due to impaired mechanical function. Preserving the regions of the...
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
abstract::Measurement of intracranial pressure (ICP) can be invaluable in the management of critically ill patients. Cerebrospinal fluid is produced by the choroid plexus in the brain ventricles (a set of communicating chambers), after which it circulates through the different ventricles and exits into the subarachnoid space ar...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aa7256
更新日期:2017-07-24 00:00:00
abstract:OBJECTIVE:Manganese (Mn) is a neurotoxin. However, the impact of elevated, chronic Mn exposure is not well understood, partially due to the lack of a cumulative exposure biomarker. To address this gap, our group developed a compact in vivo neutron activation analysis (IVNAA) system to quantify Mn concentration in bone ...
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
abstract::The purpose of this study was to investigate the linearity and reliability of the mechanomyographic (MMG) amplitude versus submaximal isometric force relationship for the vastus lateralis. Twenty healthy subjects (mean +/- SD age = 24.0 +/- 4.3 years) volunteered to perform submaximal isometric muscle actions of the d...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/30/10/002
更新日期:2009-10-01 00:00:00
abstract::In the clinical environment the reliable interpretation of EIT images depends on the quality of the data. In the electrically noisy hospital environment the system performance needs to be assessed for each clinical investigation. From the model of noise presented, a figure of merit for comparisons of system performanc...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/17/4a/006
更新日期:1996-11-01 00:00:00
abstract::Non-invasive in vivo neutron activation analysis (NAA) was used to measure the fluorine concentration in 35 people in Hamilton, Ontario, Canada. Measurement and precision data of this second generation NAA system were determined in 2013, and the results were compared with the performance of a first generation system u...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/3/465
更新日期:2015-03-01 00:00:00
abstract::This paper investigates the main characteristics of the magneto-hemodynamic (MHD) response for application as a biomarker of vascular blood flow. The induced surface potential changes of a volunteer exposed to a 3 T static B0 field of a magnetic resonance imaging (MRI) magnet were measured over time at multiple locati...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/2/117
更新日期:2012-02-01 00:00:00
abstract::Generalizability theory was used to investigate the score consistency of observed extracellular fluid/intracellular fluid (ECF/ICF) ratio measurements for both the global and leg-segmental bio-impedance spectroscopy methods. The test instrument used was a Xitron Hydra ECF/ICF Bio-Impedance Analyzer System, model 4200 ...
journal_title:Physiological measurement
pub_type: 杂志文章,随机对照试验
doi:10.1088/0967-3334/27/4/005
更新日期:2006-04-01 00:00:00
abstract::The point spread function (PSF) is the most widely used tool for quantifying the spatial resolution of imaging systems. However, prerequisites for the proper use of this tool are linearity and space invariance. Because EIT is non-linear it is only possible to compare different reconstruction algorithms using a standar...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/16/3a/021
更新日期:1995-08-01 00:00:00
abstract::Cardiac output (CO) monitoring is not only essential for critically ill patients in the hospital, but also for patients at home and those undergoing cardiopulmonary exercise testing. However, CO is difficult to monitor during daily activities and exercise. In this paper, we aim at developing a novel CO estimation meth...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/31/5/008
更新日期:2010-05-01 00:00:00
abstract::Although cardiac arrhythmias have been studied extensively, little is known about arrhythmic phenomena in the gastrointestinal (GI) system. In this study, we demonstrate for the first time that the onset of GI arrhythmias is associated with statistically significant fluctuations in the information dimension of the ass...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/5/N01
更新日期:2008-05-01 00:00:00
abstract::In the present study, laser Doppler measurement was used to quantitatively investigate the microcirculatory effects of contact pressure stimulation (PS) underneath the Hoku acupoint and its nearby nonacupoint, to improve the understanding of the mechanisms underlying acupressure therapy. A control group (no PS applied...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/31/6/007
更新日期:2010-06-01 00:00:00
abstract:OBJECTIVE:PaCO2 affects cerebral blood flow (CBF) and its regulatory mechanisms, but the effects of CO2 measurement technique on cerebrovascular parameters are unknown. In order to determine if the two most commonly used approaches, face mask (FM) or nasal cannulae (NC), are interchangeable or not, we tested the hypoth...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aa6f9f
更新日期:2017-06-22 00:00:00
abstract::Non-contact vital sign monitoring enables the estimation of vital signs, such as heart rate, respiratory rate and oxygen saturation (SpO2), by measuring subtle color changes on the skin surface using a video camera. For patients in a hospital ward, the main challenges in the development of continuous and robust non-co...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab525c
更新日期:2019-12-02 00:00:00
abstract::Dual-energy x-ray absorptiometry (DXA) is a precise, widely used method for measuring bone mineral density (BMD), usually of the lumbar spine and femoral neck. Recent developments, such as a lower x-ray tube current and pixel by pixel analysis, enable smaller bones and thinner tissues volumes, as in the hand, to be me...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/18/3/008
更新日期:1997-08-01 00:00:00
abstract:OBJECTIVE:Currently, continuous blood pressure (BP) measurements are mostly based on multi-sensor combinations and datasets with limited BP ranges. Besides, most BP-related features derive from the photoplethysmogram (PPG) signal. The mechanism of PPG signal formation is not considered. We aimed to design a noninvasive...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/abc8dd
更新日期:2021-01-01 00:00:00
abstract::A study of the concentrations of the common breath metabolites ammonia, acetone, isoprene, ethanol and acetaldehyde in the breath of five subjects over a period of 30 days has been carried out. Breath samples were taken and analysed in the early morning on arrival at the laboratory. The real time analyses of three con...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/24/1/308
更新日期:2003-02-01 00:00:00
abstract::The assessment and diagnosis of lower limb peripheral arterial occlusive disease (PAOD) is important since it can lead progressively to disabling claudication, ischaemic rest pain and gangrene. Historically, the first assessment has been palpation of the peripheral pulse since it can become damped, delayed and diminis...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/5/018
更新日期:2005-10-01 00:00:00
abstract:OBJECTIVE:To investigate if modern seismocardiography (SCG) and ballistocardiography (BCG) are useful in the detection of hemodynamic changes occurring during simulated obstructive apneic events. METHODS:Forty-seven healthy volunteers performed a voluntary maximum Mueller maneuver (MM) for 10 s, and SCG and BCG signal...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab924b
更新日期:2020-07-09 00:00:00
abstract::Arterial pCO2 is known to influence cerebral autoregulation but its effect on the dynamic relationship between mean arterial blood pressure (ABP) and mean cerebral blood flow velocity (CBFV), obtained from spontaneous fluctuations in ABP, has not been established. In 16 normal subjects, ABP was measured non-invasively...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/20/3/304
更新日期:1999-08-01 00:00:00
abstract::There is a lack of studies that examine the dynamics of heat-induced shrinkage of organ tissues. Clinical procedures such as radiofrequency ablation, microwave ablation or high-intensity focused ultrasound, use heat to treat diseases such as cancer and cardiac arrhythmia. When heat is applied to tissues, shrinkage occ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/1/55
更新日期:2014-01-01 00:00:00
abstract::Twenty-nine patients were monitored overnight for breathing distress patterns during postoperative analgesia. Nasal flow apnoea monitoring and pulse oximetry data were recorded at 50 Hz. Respiratory inductive plethysmography (RIP) tracked tidal volume (TV) thoracoabdominal motion, and supplemented the flow monitoring ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/20/2/307
更新日期:1999-05-01 00:00:00
abstract::This paper describes the design, construction, and testing of a multi-channel fetal electrocardiogram (fECG) signal generator based on LabVIEW. Special attention is paid to the fetal heart development in relation to the fetus' anatomy, physiology, and pathology. The non-invasive signal generator enables many parameter...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/2/238
更新日期:2016-02-01 00:00:00
abstract:OBJECTIVE:Atrial fibrillation (AF) causes marked risk for patients, while silent fibrillation may remain unnoticed if not suspected and screened. Development of comfortable yet accurate beat-to-beat heart rate (HR) monitoring with good AF detection sensitivity would facilitate screening and improve treatment. The purpo...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aac9a9
更新日期:2018-06-27 00:00:00
abstract::Plethysmographic measurement of airway resistance (R(aw)) has been determined by single-point analysis, usually at 50% of maximum inspiratory flow (MIF). Computer-assisted (best fit) analysis, however, allows R(aw) to be calculated by applying a regression line to any portion of the plethysmograph pressure-flow loop. ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/23/2/304
更新日期:2002-05-01 00:00:00