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Chick tibial periosteal cells were enzymatically disaggregated, introduced into cell culture, and subcultured. These subcultured cells were combined with porous calcium phosphate ceramics and implanted into a subcutaneous site in athymic mice as an immunocompatible host to test the in vivo osteochondrogenic potential of this composite graft. These cells eventually gave rise to bone tissue in the pores of ceramics at the heterotopic implantation sites. The process of bone formation occurred through two different mechanisms: Intramembranous bone formation occurred at the peripheral pores of ceramics early, and endochondral bone formation occurred in the central pores later. Cultured chick muscle fibroblasts of the same-aged donor as controls did not form bone or cartilage under identical conditions to those of cultured periosteal-derived cells. These results raise the possibility that composite graft of cultured periosteal-derived cells and porous ceramics can be clinically used as a bone graft substitute in situations requiring bone augmentation or regeneration.  相似文献   
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Our goal was to study deglutition of Parkinson??s disease (PD) patients and normal controls (NC) using surface electromyography (sEMG). The study included 15 patients with idiopathic PD and 15 age-matched normal controls. Surface electromyography was collected over the suprahyoid muscle group. Conditions were the following: swallow at once 10 and 20?ml of water and 5 and 10?ml of yogurt of firm consistency, and freely drink 100?ml of water. During swallowing, durations of sEMG were significantly longer in PD patients than in normal controls but no significant differences of amplitudes were found. Eighty percent of the PD patients and 20?% of the NC needed more than one swallow to consume 20?ml of water, while 70?% of the PD patients and none of the NC needed more than one swallow to consume 5?ml of yogurt. PD patients took significantly more time and needed significantly more swallows to drink 100?ml of water than normal controls. We conclude that sEMG might be a simple and useful tool to study and monitor deglutition in PD patients.  相似文献   
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This study examined if children with cryptogenic epilepsy and complex partial seizures (CPS) have smaller total brain, frontal, and temporal lobe volumes than normal children and how this is related to seizure, cognitive, psychiatric, and demographic variables. Forty-four children with CPS and 38 normal children, aged 5-16 years, underwent brain MRI scans at 1.5 T. Tissue was segmented, and total brain, frontal lobe, frontal parcellation, and temporal lobe volumes were computed. Other than significantly larger temporal lobe white matter volumes in the CPS group, there were no significant differences in brain volumes between the CPS and normal groups. Earlier onset, longer duration of illness, younger chronological age, and presence of a psychiatric diagnosis were significantly related to smaller frontotemporal volumes in subjects with CPS. Although these findings suggest that CPS might affect development of the temporal and frontal regions, we are unable to rule out the possibility that smaller frontotemporal volumes might predispose children to CPS. These findings highlight the need to control for seizure, cognitive, psychiatric, and demographic variables in studies of frontotemporal volumes in pediatric CPS.  相似文献   
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