Abstract

These studies explore the distribution of blood flow among small samples of placental tissue. Labeled microspheres (14 ± 1 pm) were Injected Into the left ventricle of six un-anesthetized ewes and Into the jugular vein of the fetus In utero. A total of 3,576 samples weighing 31. +11. (S.D.) mg were taken from seventeen cotyledons and counted for flow labels. Maternal and fetal flow within the cotyledons were both normally distributed with standard deviations of 44%. The maternal/ fetal flow ratio was less than 0.5 In 9% of the cotyledon, between 0.5 and 1.5 In 70%, and greater than 1.5 In 21%. Errors due to the method were estimated to contribute less than 10% of the flow variances. Maternal and fetal flows were significantly correlated (r = 0.57, p < .001). Spatial flow patterns were visualized using computerized Image processing. The distribution of maternal and fetal flow may be a sensitive determinant of water transfer, and the distribution of their ratio explains about 50% of the uterine—umbilical venous oxygen tension gradient. Analysis of the correlation between samples vs. the distance separating them suggested a weight of roughly 125 mg for hypothetical placental regulatory units.

Department

Bioinformatics & Computational Biology

School

Graduate School

First Advisor

Ivan R. Neilsen

Second Advisor

Gordon G. Power

Third Advisor

C. Duane Zimmerman

Fourth Advisor

S. Andrew Yakush

Fifth Advisor

Paul Y. Yahiku

Degree Name

Master of Science (MS)

Degree Level

M.S.

Year Degree Awarded

1980

Date (Title Page)

8-1980

Language

English

Library of Congress/MESH Subject Headings

Maternal-Fetal Exchange; Fetal Blood; Placenta

Type

Thesis

Page Count

iii; 40

Digital Format

PDF

Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Collection

Loma Linda University Electronic Theses and Dissertations

Collection Website

http://scholarsrepository.llu.edu/etd/

Repository

Loma Linda University. Del E. Webb Memorial Library. University Archives

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