薬剤抵抗性てんかんにおける発作間欠期高周波律動に対する定常濃度プロポフォールの影響

京都大学新制・課程博士博士(医学)甲第23420号医博第4765号新制||医||1053(附属図書館)京都大学大学院医学研究科医学専攻(主査)教授 髙橋 良輔, 教授 林 康紀, 教授 福田 和彦学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDFA

Analysis of Revision Surgery of Microsurgical Lumbar Discectomy

Study DesignA retrospective study.PurposeOur objectives were to determine the association between the pathological changes of disc herniation and the interval between primary and revision surgeries and to investigate the frequency and site of the dural laceration in the primary and revision surgeries.Overview of LiteratureAmong 382 patients who underwent microsurgical lumbar discectomy, we investigated 29 who underwent revision surgery to analyze recurrent herniation pathologies and complications to determine the manner in which lumbar disc herniation can be more efficiently managed.MethodsOf 29 patients, 22 had recurrent disc herniation at the same level and site. The pathological changes associated with compression factors were classified into the following two types depending on intraoperative findings: (1) true recurrence and (2) minor recurrence with peridural fibrosis (>4 mm thickness). The sites of dural laceration were examined using video footage and operative records.ResultsThe pathological findings and days between the primary and revision surgeries showed no statistical difference (p=0.14). Analysis of multiple factors, revealed no significant difference between the primary and revision surgery groups with regard to hospital days (p=0.23), blood loss (p=0.99), and operative time (p=0.67). Dural lacerations obviously increased in the revision surgery group (1.3% vs. 16.7%, p<0.01) and were mainly located near the herniated disc in the primary surgery group and near the root shoulder in the revision surgery group, where severe fibrosis and adhesion were confirmed. To avoid dural laceration during revision surgery, meticulous decompressive manipulation must be performed around the root sleeve.ConclusionsWe recommend that meticulous epidural dissection around the scar formation must be performed during revision surgery to avoid complications

Appearance of Ferromagnetic Property for Si Nanopolycrystalline Body and Vanishing of Electrical Resistances at Local High Frequencies

Reduction in the skin effect for the sintered Si nanopolycrystalline body as an electricity conductor at a high frequency due to its nanostructure was studied. Singular disappearance of electrical resistances near a local high magnetic harmonic frequency of a few MHz was observed. This phenomenon has not been observed for conventional ferromagnetic metals. The measured electrical resistances changed to almost 0 mΩ at room temperature. At the same time, negative resistance of the sintered Si nanopolycrystalline body was observed. It will be applicable to electronic transmittance lines or semiconductors. Numerical calculation was also performed on the electrical resistance with frequency dependency while considering the electric field and magnetic field in the sintered Si nanopolycrystalline body. The experimental and calculated results are compared. The calculation could explain the variation of the relative permittivity of the Si nanopolycrystalline body and the phenomenon for the theoretical disappearance of the resistivity at the MHz frequency. Reduced Si nanoparticles from SiO2 powder were synthesized by laser ablation in liquid. A Si nanopolycrystalline body made of the reduced Si nanoparticles was fabricated. It was found by measuring the magnetization property of the body of the sintered Si nanopolycrystalline body which is ferromagnetic. Dangling bonds (unpaired electrons) have long been known to occur due to defects in Si crystals. Perfect Si without defective crystals has no dangling bonds. However, Si nanoparticles have many dangling bonds. High-density dangling bonds cause the sintered Si nanopolycrystalline body to have ferromagnetism. In this study, the density of the unpaired electrons in the sintered Si nanopolycrystalline body was observed using ESR. It has been clarified that the Si nanopowder and the sintered Si nanopolycrystalline body have numerous dangling bonds. Both densities of the dangling bonds were evaluated