Percutaneous Penetration of Nicotinates: In Vivo and In Vitro Measurements

1986 ◽  
Vol 75 (10) ◽  
pp. 968-972 ◽  
Author(s):  
Richard H.A. Guy ◽  
Eva M. Carlström ◽  
Daniel A.W. Bucks ◽  
Robert S. Hinz ◽  
Howard I. Maibach
Keyword(s):  
Percutaneous Penetration ◽  
In Vitro Measurements

Correlation of in vivo and in vitro measurements of sun protection factor

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
M.-T. Sheu ◽  
C.-W. Lin ◽  
M.-C. Huang ◽  
C.-H. Shen ◽  
H.-O. Ho
Keyword(s):  
Sun Protection ◽  
Protection Factor ◽  
In Vitro Measurements ◽  
Sun Protection Factor

scholarly journals Advances in Photoacoustic Noninvasive Glucose Testing

1999 ◽  
Vol 45 (9) ◽  
pp. 1587-1595 ◽  
Author(s):  
Hugh A MacKenzie ◽  
Helen S Ashton ◽  
Stephen Spiers ◽  
Yaochun Shen ◽  
Scott S Freeborn ◽  
...  
Keyword(s):  
Glucose Measurement ◽  
Oral Glucose ◽  
Physiological Factors ◽  
Glucose Testing ◽  
In Vivo Experiments ◽  
In Vitro Measurements ◽  
Clinical Measurements ◽  
Blood Analytes

Abstract We report here on in vitro and in vivo experiments that are intended to explore the feasibility of photoacoustic spectroscopy as a tool for the noninvasive measurement of blood glucose. The in vivo results from oral glucose tests on eight subjects showed good correlation with clinical measurements but indicated that physiological factors and person-to-person variability are important. In vitro measurements showed that the sensitivity of the glucose measurement is unaffected by the presence of common blood analytes but that there can be substantial shifts in baseline values. The results indicate the need for spectroscopic data to develop algorithms for the detection of glucose in the presence of other analytes.

scholarly journals Intraperitoneal pressure: Stability over time and validation of Durand’s measurement method

2020 ◽  
pp. 089686082097312
Author(s):  
Alicia Sobrino-Pérez ◽  
Alfonso Pérez-Escudero ◽  
Lucila Fernández-Arroyo ◽  
Ana Dorado-García ◽  
Berta Martín-Alcón ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Venous Pressure ◽  
Relevant Parameter ◽  
Pressure System ◽  
Intraperitoneal Pressure ◽  
In Vitro Measurements ◽  
Long Timescales ◽  
Over Time

Intraperitoneal pressure (IPP) is gaining consideration as a relevant parameter of peritoneal dialysis (PD) in adults, although many of its aspects are still pending clarification. We address here its stability over time and the validity of the usual method of clinical measurement, as proposed by Durand in 1992 but never specifically validated. We performed this validation by comparing Durand’s method and direct measurements with a central venous pressure system. We performed a total of 250 measurement pairs in 50 patients with different intraperitoneal volumes plus in-vitro measurements with a simulated peritoneum. Absolute differences between the two systems in vivo were 0.87 ± 0.91 cmH2O (range 0–5 cmH2O); only 6.4% of them were ≥3 cmH2O. In vitro results for both methods were identical. We also compared IPP measurements in the same patient separated by 1–4 h (514 measurement pairs in 136 patients), 1 week (92 pairs in 92 patients), and 2 years (34 pairs in 17 patients). Net differences of measurements separated by hours or 1 week were close to 0 cmH2O, with oscillations of 1.5 cmH2O in hours and 2.3 cmH2O in 1 week. IPP measured 2 years apart presented a net decrease of 2.5 ± 4.9 cmH2O, without correlation with body mass index changes or any other usual parameter of PD. In hours, 7% of IPP differences were >3 cmH2O, 22% in 1 week, and 50% in 2 years. In conclusion, Durand’s method is precise enough to measure IPP in peritoneal dialysis. This parameter is not stable over long timescales, so it is necessary to use recent measurements.

In Vivo Compliance of the Human Saphenous Vein Measured by Sonography: Comparison with Plethysmographic and in vitro Measurements

1995 ◽  
Vol 10 (4) ◽  
pp. 143-148 ◽  
Author(s):  
G. Lefthériotis ◽  
Th. Pochet ◽  
P. Abraham ◽  
J. B. Subayi-Kamuanga ◽  
A. Jardel ◽  
...  
Keyword(s):  
Saphenous Vein ◽  
Bypass Surgery ◽  
Coronary Bypass ◽  
Coronary Bypass Surgery ◽  
University Hospital ◽  
Human Saphenous Vein ◽  
Venous Compliance ◽  
In Vitro Measurements

Objective: To evaluate a non-invasive and selective measurement of in vivo venous compliance of the human saphenous vein using sonography. Design: An experimental study in patients prior to coronary bypass surgery. Setting: Departments of Physiology and Cardiothoracic Surgery, University Hospital of Angers. Patients: Thirty patients investigated prior to coronary bypass surgery. Interventions: Simultaneous strain-gauge venous occlusion plethysmography (VOP) and measurements of the circumference of the great saphenous vein by sonography at four different occlusion pressures: 20, 30, 40 and 50 mmHg. In 10 of the same patients, in vitro determination of pressure–volume relationship during progressive inflation of excised saphenous vein samples. Main outcome measures: Venous compliance obtained with the three methods. Results: Weak correlation coefficients were found between in vitro measurements and VOP ( r=0.478, p<0.01) and sonography ( r=0.497, p<0.02). Although individual correlations between in vitro and VOP measurements ranged from 0.928 to 0.999, a wide heterogeneity was found with sonography (from 0.620 to 0.985). Conclusions: Sonography allows the selective measurement of in vivo venous compliance, although the measured compliances differ from other techniques.

Autofluorescence Detection of Tumors in the Human Lung -- Comparison between in vivo and in vitro Measurements

2005 ◽  
Author(s):  
Dirk Hüttenberger ◽  
Tanja Gabrecht ◽  
G. Wagnieres ◽  
B. Weber ◽  
Albert Linder ◽  
...  
Keyword(s):  
Human Lung ◽  
In Vitro Measurements
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