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101.
Summary:  The origins of human mesial temporal lobe epilepsy and hippocampal sclerosis are still not well understood. Hippocampal sclerosis and temporal lobe epileptogenesis involve a series of pathologies including hippocampal neuronal loss and gliosis, axonal reorganization, and maybe hippocampal neoneurogenesis. However, the causality of these events is unclear as well as their relation to the factors that may precipitate epileptogenesis. Significant differences between temporal lobe epileptogenesis in the adult and immature brain may require differential approaches. Hereditary factors also may participate in some cases of hippocampal sclerosis. The key point is to identify the significance of these age-dependent changes and to design preventive treatments. Novel strategies for the prevention and treatment of mesial temporal lobe epilepsy and hippocampal sclerosis may include rational use of neuroprotective agents, hormonotherapy, immunizations, and immunotherapy.  相似文献   
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Problems that can occur when single implants are utilized to restore first molar teeth include the frequent loosening of screws, as well as screws and/or implant breakage. These may result from torquing and rotational movements of the prosthesis during masticatory and parafunctional mandibular movements. When sufficient bone and mesio-distal restorative space is present, the placement of two implants should be considered.  相似文献   
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Statement of problem. Controversy surrounds the use of hydrofluoric acid to prepare precementation surfaces of indirect composites.Purpose. This study was conducted to compare effects of combining hydrofluoric or orthophosphoric acid with microetching as precementation treatments.Material and methods. Nine specimens of three composite materials were prepared to simulate heat-cured indirect restorations. The specimen surfaces were prepared with one of three treatments. Adhesive Bond II and Twinlook cements were used to bond a phosphoric acid-etched disk of P50 to the treated surface. Analysis of variance and Scheffé tests were used to assess the bond strength data. Scanning electron microscopy and microscopic analysis of the fractured and treated surfaces were also performed.Results. Bond strengths for all surface treatments did not significantly differ. Hybrids had a higher bond strength with etching than microfills, and mechanical roughening produced the greatest bond strengths with microfills. Microetching with orthophosphoric acid produced higher bond strengths than microetching with hydrofluoric acid on hybrids.Conclusions. Acid etching alone is not sufficient to produce effective bond strengths, and hydrofluoric acid treatments are detrimental to the resin composite. (J Prosthet Dent 1997;77:568-72.)  相似文献   
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We present a case of Merkel cell carcinoma of the thigh diagnosed by conventional histology, immunohistochemistry, electron microscopy and cytogenetics. A unique chromosome 6 trisomy characterized this primary neoplasm, as confirmed by FISH study. The role of chromosome analysis and interphase cytogenetics is emphasized as an adjunct in the subtyping of tumours and their prognostic evaluation.  相似文献   
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