Gastric activity studies using a magnetic tracer.

Abstract:

:A magnetic pulse generator has been set up in order to study gastric activity. Two coils 1.05 m in diameter, arranged in a Helmholtz configuration, were used. The system generated magnetic field pulses higher than 15 mT, of duration 17.3+/-1.2 ms. Measurements were performed in 11 male volunteers, with average age 29.3+/-6.4 years and body mass index 26.0+/-4.8 kg m(-2). Magnetite (Fe3O4) particles with diameters from 75 to 125 microm were used as magnetic tracers, which were mixed in 250 ml of yogurt in concentrations from 2 to 5 g. Signals were registered by using a high speed 3 axis fluxgate digital magnetometer and processed to determine the relaxation of the magnetic tracers by fitting a first-order exponential function to the data, a mean relaxation constant K = 116+/-40 s(-1) was obtained. Also, an average gastric peristaltic frequency was measured; a value of 3.2+/-0.3 cpm was determined.

journal_name

Physiol Meas

authors

Cordova-Fraga T,Bernal-Alvarado JJ,Gutierrez-Juarez G,Sosa M,Vargas-Luna M

doi

10.1088/0967-3334/25/5/015

subject

Has Abstract

pub_date

2004-10-01 00:00:00

pages

1261-70

issue

5

eissn

0967-3334

issn

1361-6579

journal_volume

25

pub_type

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