Abstract:
:The outflow conductance (C(out)) of the cerebrospinal fluid (CSF) system is a parameter considered to be predictive in selection for hydrocephalus surgery. C(out) can be determined through an infusion test. A new apparatus for performing infusion tests in a standardized and automated way was developed. The objective was to evaluate repetitiveness as well as to propose and evaluate a method for real time estimation of the reliability of individual C(out) investigations. Repeated investigations were performed on an experimental model simulating the CSF system, and on 14 patients with hydrocephalus. DeltaC(out), calculated as the 95% confidence interval of C(out), was introduced as an estimate of the reliability of individual C(out) investigations. On the model, no significant difference was found between DeltaC(out) and the actual C(out) variation in repeated investigations (p = 0.135). The correlation between the first and the second patient investigation was high (R = 0.99, p < 0.05), although there was a significant difference between the investigations (p < 0.05). The standard deviation of difference was 2.60 microl (s kPa)(-1). The repetitiveness of C(out) with the new apparatus was high, and DeltaC(out) reflected the reliability of each investigation. This feature has to be taken into account in every individual case, before making a decision or performing research based on measurements of C(out) in the future.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Andersson N,Malm J,Bäcklund T,Eklund Adoi
10.1088/0967-3334/26/6/022subject
Has Abstractpub_date
2005-12-01 00:00:00pages
1137-48issue
6eissn
0967-3334issn
1361-6579pii
S0967-3334(05)03299-5journal_volume
26pub_type
杂志文章abstract::Chemical alterations of red blood cells (RBCs) during storage eventually affect the electrical properties of blood. In this study, the physiological parameters such as extracellular (SAGM + CPD + residual plasma) Na(+), K(+), Cl(-), pH, 2,3-DPG and ATP together with the Cole-Cole parameters were measured using erythro...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/7/006
更新日期:2006-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aa6d00
更新日期:2017-06-01 00:00:00
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更新日期:1994-02-01 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:2007-07-01 00:00:00
abstract::Neuromagnetic recordings were used to check if electrical stimulation of the auditory nerve in cochlear-implant patients activates cortical auditory areas in a similar manner as acoustic stimulation in normal hearing subjects or whether the excitation processes are different. The waveform of the evoked magnetic field ...
journal_title:Physiological measurement
pub_type: 杂志文章,评审
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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:10.1088/1361-6579/ab9e53
更新日期:2020-11-06 00:00:00
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pub_type: 杂志文章
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更新日期:2016-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/10/2159
更新日期:2015-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/9/004
更新日期:2007-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/4/001
更新日期:2007-04-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/2/002
更新日期:1994-05-01 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
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/33/2/207
更新日期:2012-02-01 00:00:00
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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
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/abb8bf
更新日期:2020-11-06 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/1/001
更新日期:2004-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaaeb2
更新日期:2018-03-29 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/9/008
更新日期:2011-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/6/1119
更新日期:2015-06-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2012-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/32/4/008
更新日期:2011-04-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2001-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab37db
更新日期:2019-09-03 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
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/38/1/63
更新日期:2017-01-01 00:00:00
abstract::The aim of the study was to investigate whether body mass index (BMI) influences the estimation of extracellular volume (ECV) in hemodialysis (HD) patients when using segmental bioimpedance analysis (SBIA) compared to wrist-to-ankle bioimpedance analysis (WBIA) during HD with ultrafiltration (UF). Twenty five HD patie...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/26/2/009
更新日期:2005-04-01 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
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/4/597
更新日期:2014-04-01 00:00:00
abstract::There is considerable interest in unobtrusive and portable methods of monitoring sleepiness outside the laboratory setting. This study evaluates the usefulness of combined electrocardiogram (ECG) and photoplethysmogram (PPG) measurements for estimating psychomotor vigilance. The psychomotor vigilance test (PVT) was pe...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/8/001
更新日期:2008-08-01 00:00:00
abstract::The standard electrocardiogram (ECG) is the most common non-invasive way to study atrial fibrillation (AF). In this respect, previous works have shown that the surface lead V(1) reflects mainly the dominant atrial frequency (DAF) of the right atrium (RA), which has been widely used to study AF. In a similar way, AF or...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/1/007
更新日期:2011-01-01 00:00:00