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Estimation of Three-Dimensional Velocity Structure Based on Autocorrelation Functions Using Seismic Ground Motion Records at a Single Station [an abstract of dissertation and a summary of dissertation review]
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A Study on Pathological Predictive Factors Related to the Therapeutic Effects and Long-term Prognosis of Preoperative Chemoradiotherapy in Locally Advanced Rectal Cancer [an abstract of dissertation and a summary of dissertation review]
No full text配架番号：290
抗RANKL 中和抗体単回投与後のマウス根間中隔及び槽間中隔における組織化学的検索 [全文の要約]
No full textこの博士論文全文の閲覧方法については、以下のサイトをご参照ください。https://www.lib.hokudai.ac.jp/dissertations/copy-guides
ラット脛骨に埋入したハイドロキシアパタイトコラーゲンナノ複合材における破骨細胞と骨芽細胞分布の組織化学的解析
No full textObjective: To clarify how the orientation of hydroxyapatite and collagen bone-like nanocomposite (HAp/Col) fibers in a HAp/Col block affects bone resorption and formation, HAp/Col cylinders with laminated collagen layers were implanted into the tibial diaphysis of rats and examined histochemically. Materials and Methods: HAp/Col fibers were synthesized by the simultaneous titration method to form HAp nanocrystals on collagen fibers similar to bone nanostructure. Cylindrical HAp/Col blocks were formed by uni-axially compressing to layer them with maintaining their consistent horizontal alignment. The cylindrical HAp/Col grafts were implanted into cortical bone cavities of 10-week-old male Wistar rats, ensuring that the HAp/Col fiber bundles were parallel to the tibial surface. The blocks were analyzed histologically 3, 5, 7, 14, and 28 days after implantation in two regions: the lateral side facing the cortical bone (perpendicular to the HAp/Col layers), and the bottom region (near the marrow, parallel to the collagen layers). Results and Discussion: TRAP-positive osteoclasts were observed in the lateral region 3–5 days after implantation but rarely seen in the bottom region. By day 7, many TRAP-positive osteoclasts had accumulated only in the lateral region, while osteoclasts appeared in both regions by day 14. By day 28, many osteoclasts were present throughout the cylinder. PHOSPHO1-positive osteoblasts were first detected on day 5, located slightly away from the HAp/Col cylinder in the lateral region, while in the bottom region, they were on the cylinder’s surface. Between days 7 and 14, few PHOSPHO1-positive osteoblasts directly contacted the block in the lateral region, while many were observed on newly formed bone in the bottom region. By day 28, lines of PHOSPHO1-positive osteoblasts were seen in the cylinder’s interior. Thus, bone formation was induced earlier in the bottom region, where HAp/Col fibers were parallel, while bone resorption was predominant in the lateral region, where the fiber ends were exposed. These findings suggest that bone resorption and formation were uncoupled in the early stages after HAp/Col block implantation. By day 28, bone remodeling had shifted to a coupling between osteoclasts and osteoblasts, with neither resorption nor formation dominating in either region. Conclusions: The orientation of HAp/Col fibers in the HAp/Col block significantly affects whether bone resorption or formation is preferentially induced during the early stages of bone regeneration
