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The temporomandibular joint has many complex anatomical and functional features compared with other joints. Therefore, caution should be exercised in the diagnosis of temporomandibular joint fractures. Although panoramic tomography is widely used for the screening of orofacial trauma as well as other diseases, this modality often overlooks evidence of a condylar fracture. Cone-beam computed tomography is also used for diagnosing orofacial diseases. The purposes of this report are to show the usefulness of cone-beam computed tomography in diagnosing condylar fractures and to describe the imaging features of condylar fractures.  相似文献   
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The present report describes the application of a miniplate in the hard palate of a 36-year-old patient with a large anterior maxillary defect. The combination of orthodontic elastics with a titanium miniplate improved the stability of the prefabricated prosthesis. This structure retained the ointment gauze covering the wounds and maintained the facial contour. In addition, contracture deformity was prevented by insertion of the prefabricated prosthesis intraoperatively or immediately postoperatively. Furthermore, a soft diet could be ingested immediately postoperatively. The miniplate also supported the anterior part and the definitive prosthesis. This prosthesis restored adequate masticatory, deglutitive, and speech functions and maintained the facial contour with minimum overloading of the remaining teeth.  相似文献   
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Abstract

Consistently reproducible experimental trauma was inflicted on the rat spinal cord (L3-L4) employing a controlled cortical impact device. The spinal cord was injured with one of three sizes of chips; thick (3 mm diameter), medium (2 mm diameter), thin (1 mm diameter). Each chip was applied at ), 2 and 3 mm deformation depths. The correlations of the magnitude of the primary trauma were examined histopathologically. It was found that the extent and intensity of the trauma could be changed by altering the depth of deformation and the chip diameter at a fixed velocity of 4.6 m per sec. The injury caused by the 2 mm diameter chip at 0.5 mm deformation damaged one to two segments of the perifocal spinal cord. In the surviving animals, the histological changes could be classified as primary, secondary, and late phase changes, and finally the lesion became a cavity. This study reports the application of a controlled cortical impact device to morphological research on a spinal cord injury. We found that the injury by the 2 mm chip at 0.5 mm deformation was the most advantageous and reproducible model for further investigations. [Neurol Res 1999; 21: 313–323]  相似文献   
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We have previously reported free radical production after traumatic brain injury (TBI), which induces neural stem cell (NSC) degeneration and death. However, the effects of aging on NSC proliferation around the damaged area following TBI have not been investigated. Therefore, in this study, we used 10-week (young group) and 24-month-old (aged group) rat TBI models to investigate the effects of aging on NSC proliferation around damaged tissue using immunohistochemical and ex vivo techniques. Young and aged rats received TBI. At 1, 3 and 7 days after TBI, immunohistochemical and lipid peroxidation studies were performed. Immunohistochemistry revealed that the number of nestin-positive cells around the damaged area after TBI in the aged group decreased significantly when compared with those in the young group (P < 0.01). However, the number of 8-hydroxy-2′-deoxyguanosine-, 4-hydroxy-2-nonenal- and single-stranded DNA (ssDNA)-positive cells and the level of peroxidation around the damaged area after TBI significantly increased in the aged group, compared with those in the young group (P < 0.01). Furthermore, almost all ssDNA-positive cells in young and aged groups co-localized with NeuN and nestin staining. Ex vivo studies revealed that neurospheres, which differentiated into neurons and glia in culture, could only be isolated from injured brain tissue in young and aged groups at 3 days after TBI. These results indicate that, although there were fewer NSCs that have the potential to differentiate into neurons and glia, these NSCs escaped free radical-induced degeneration around the damaged area after TBI in the aged rat brain.  相似文献   
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