RESUMO
BACKGROUND: Whole blood viscosity is the keystone in hemorheological research, which has important significance in the exposure of the generation of ischemic diseases including myocardial infarction (MI) and cerebral infarction(CI) due to hemorheological changes.OBJECTIVE: To investigate the characters of macroscopical and microscopical hemorheology to explore the standardization of hemorheological measuring method.DESIGN: An observatory comparative study based on the venous blood of healthy individual.SETTING: Department of physics in a medical college.MATERIALS: Venous bloods of 86 healthy individuals were randomly selected for the study, which was conducted in the Laboratory of Hemorheology of Guilin Medical College.METHODS: Totally 86 whole blood samples were tested under 7 shear rates (0.6 s-1,2 s-1,5 s-1, 10 s-1, 20 s-1, 40 s-1, 100 s-1) from low shear rate to high shear rate, and then from high shear rate to low shear rate. The measuring value of the two processes was compared.Casson viscosity and yield stress in two measuring process.RESULTS: There was no significant difference of apparent viscosity( P＞ 0.05 ) except the 0.6 s- 1 -corresponding apparent viscosity ( P ＜ 0.05 )at some shear rate in two measuring process. There was no significant difference in Casson viscosity and yield stress( P ＞ 0.5, P ＞ 0. 3).CONCLUSION: The measurement of Casson viscosity and yield stress is good for the optimization of the standardization of hemorheological indicators and measuring method; and it is feasible to test apparent viscosity, Casson viscosity and yield stress repeatedly in same blood sample, which has important significance in the exposure of the hemorheological changes and the generation and development mechanism of ischemic diseases including MI,CI, hypertension, and coronary heart disease(CHD).
