Abstract:
:Blood was withdrawn from the ante-cubital vein of five normal volunteers and the erythrocytes were washed and resuspended in isotonic saline. The rate of descent of the erythrocyte-saline boundary was measured every hour for a period of at least 4 h for different suspended cell concentrations. The velocity of this boundary remained constant during the period of observation for a specific concentration. There was, however, an experimental variation of sedimentation rate with red cell concentration. Extrapolation to zero concentration allowed the 'Svedberg constant' for normal red cells to be evaluated. A continuum physics theory was used to explain the observations. The sedimentation rate was also measured in anticoagulated whole blood. The rates of descent in whole blood and the red cell-saline suspension were significantly different. Furthermore, the erythrocyte boundary in whole blood displayed both acceleration and deceleration during the period of observation. These experiments support the concept, proposed in an earlier theoretical study, of an internal energy dissipative mechanism which occurs in heterogeneous fluids (such as blood) but not in homogeneous fluids (such as water).
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Smallwood RH,Tindale WB,Trowbridge EAdoi
10.1088/0031-9155/30/2/002subject
Has Abstractpub_date
1985-02-01 00:00:00pages
125-37issue
2eissn
0031-9155issn
1361-6560journal_volume
30pub_type
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