AIM: To study the effect of ?-amyloid protein (?-AP) and D-galactose(D-gal) on learning-memory and SOD activity and MDA content of hippocampus in rats. METHODS: The behaviors of rats were measured by using open field, Y-maze and one-trial passive avoidance response, and the content of SOD and MDA were measured. RESULTS: In the D-gal and D-gal+?-AP group rats, the spontaneous activities and responses to novel environment in the open field were significantly decreased, and the abilities of learning-memory were remarkably attenuated, the content of SOD decreased and MDA content increased markedly in hippocampus (P

Objective To study the effect of age on the hemodynamics of common carotid artery. Methods 47 healthy volunteers werestudied. Wall shear stress (WSS) values localized at common carotid artery 2 cm below the bifurcation were calculated with cine phase-contrastMR imaging combined three-dimensional paraboloid (3DP) model. On the spatial distribution, common carotid artery wall was dividedinto 24 equal parts. Calculate the mean WSS in a cardiac cycle on each part, and choose the minimal WSS value. Then the effects of age onthe average WSS and minimal WSS were observed. Results Total 94 common carotid arteries of 47 health volunteers were examined, inwhich 9 carotid arteries in 9 volunteers were excluded because of uninterpretable high-resolution MRI findings or volunteer's intolerance forthe detection. In the remaining 85 common carotid arteries, the average WSS and the minimal WSS during a cardiac cycle on the spatial distributionwere (7.45±2.12) dyne/cm2 and (5.98±1.93) dyne/cm2 respectively. Both average WSS and minimal WSS were negative correlatedwith age (P<0.05). Conclusion With the age increased, mean WSS and minimal WSS on the spatial distribution of common carotid arterydecreased.