Objective To study the clinical and neuroimaging features of top of the basilar artery syndrome(TOBS).Methods The clinical and neuroimaging features of 63 cases with TOBS were analyzed retrospectively.Results Main causes of TOBS were atherosclerosis and embolisms.Vertigo and disturbance of consciousness and movement of the eye-ball,abnormality of pupils,partial blindness were the main clinical features.The most important imageologic feature of TOBS was infarction of thalami or midbrain,which was frequently complicating with infarction in other locations.Conclusion TOBS has simultaneously more than two infarction lesions,either superior or inferior tentorium of cerebellum with many complications and poor prognosis.MRI is more sensitive than CT.Early MRI examination,systemic and comprehansive treatment may improve the prognosis of the TOBS patients.

Objective To investigate the conduction behavior of fluid flow induced by physiological loads at different scales of bone. Method sThe multiscale bone models were established by using the COMSOL Multiphysics software, and the fluid behaviors were investigated at macro-, meso- and micro-scale. Results At macro-meso scale，the distribution of pore pressure and fluid velocity of osteon near the periosteum and endoosteum were different from that in other parts. Due to the different structure and material parameters at different layers, the loading and fluid pressure caused different biomechanical responses in the process of transferring from macro-scale to micro-scale. Conclusions The multi-scale layered modeling of bone structure-osteon-lacunae-bone canaliculi was established, which provided the theoretical reference for deeper understanding of fluid stimulation and mechanotransduction.