Objective To Investigate stress adaptability of freeze-dried bone allograft.Methods Cortical and cancellous allograft were transplanted to each side of the midshaft diaphyseal ulna in two groups of 28 animals.The left...Objective To Investigate stress adaptability of freeze-dried bone allograft.Methods Cortical and cancellous allograft were transplanted to each side of the midshaft diaphyseal ulna in two groups of 28 animals.The left transplanted allograft was free from fixation and bore a normal physiological lcad,while the right transplanted allograft was protected from loading by a simple external fixator and bore less load.Animals were sacrificed at the 2nd,4th,8th,16th week after transplantation and specimens were taken out for bone histomorphometry studies and analysis of collagen gene expression by in situ Cdna-Mrna hybridization.Results Labeled surface(LS)and bone mineral apposition rate(MAR)of the normally loaded graft-host bone interface were significantly higher than that of the less loaded side at the 4th,8th,16th week after transplantation.Parameters reflecting the internal repair process of the allograft,such as LS in cortical and cancellous bone or MAR in cortical bone of the normally loaded side were significantly higher than those of the less loaded side at the 16th week after transplantation.The result of in situ hybridization indicated that more osteoblast-like cells expressing the type Ⅰ collagen gene were found in the interface or interior of normally loaded grafts.Conclusion The stimulus of physiologic load can accelerate the early union of allograft-host bone interface and later new bone creep substitution to the necrotic allograft.展开更多
Silicene, a new allotrope of silicon in a twodimensional honeycomb structure, has attracted intensive research interest due to its novel physical and chemical properties. Unlike carbon atoms in graphene, silicon atoms...Silicene, a new allotrope of silicon in a twodimensional honeycomb structure, has attracted intensive research interest due to its novel physical and chemical properties. Unlike carbon atoms in graphene, silicon atoms prefer to adopt sp2/sp3-hybridized state in silicene,enhancing chemical activity on the surface and allowing tunable electronic states by chemical functionalization. The silicene monolayers epitaxially grown on Ag(111) surfaces demonstrate various reconstructions with different electronic structures. In this article, the structure, phonon modes, electronic properties, and chemical properties of silicene are reviewed based on theoretical and experimental works in recent years.展开更多
Objective: To observe the survival of hand allograft under the state of immunosuppression and the pathological changes of rejection in the recovery process. Methods: The biopsies of the skin, nerve, muscle, tendon and...Objective: To observe the survival of hand allograft under the state of immunosuppression and the pathological changes of rejection in the recovery process. Methods: The biopsies of the skin, nerve, muscle, tendon and bone tissue of hand allografts during different stages from 1 day to 7 months after operation were observed using routine histological technique. Results: No significant changes due to rejection in skin, nerve, muscle and bone tissue were observed. But different degrees of weak rejective changes were found on the wall of blood vessels; in the muscle and nerve the reactions were markedly stronger than those found in skin tissues. Conclusions: The rejection in deep tissues should be monitored in controlling the rejection of hand allograft.展开更多
Configuration-constrained calculations of potential-energy surfaces for ^292 122 show the occurrence of multiquasiparticle high-K isomeric state at oblate superdeformation. Such state could play a unique role in super...Configuration-constrained calculations of potential-energy surfaces for ^292 122 show the occurrence of multiquasiparticle high-K isomeric state at oblate superdeformation. Such state could play a unique role in superheavy nuclei, with possible long life time from enhanced difficulty in fission due to additional barrier at oblate deformation, retardation in a decay due to unpaired nucleons, and hindrance in γ-ray transition due to K forbiddenness.展开更多
文摘Objective To Investigate stress adaptability of freeze-dried bone allograft.Methods Cortical and cancellous allograft were transplanted to each side of the midshaft diaphyseal ulna in two groups of 28 animals.The left transplanted allograft was free from fixation and bore a normal physiological lcad,while the right transplanted allograft was protected from loading by a simple external fixator and bore less load.Animals were sacrificed at the 2nd,4th,8th,16th week after transplantation and specimens were taken out for bone histomorphometry studies and analysis of collagen gene expression by in situ Cdna-Mrna hybridization.Results Labeled surface(LS)and bone mineral apposition rate(MAR)of the normally loaded graft-host bone interface were significantly higher than that of the less loaded side at the 4th,8th,16th week after transplantation.Parameters reflecting the internal repair process of the allograft,such as LS in cortical and cancellous bone or MAR in cortical bone of the normally loaded side were significantly higher than those of the less loaded side at the 16th week after transplantation.The result of in situ hybridization indicated that more osteoblast-like cells expressing the type Ⅰ collagen gene were found in the interface or interior of normally loaded grafts.Conclusion The stimulus of physiologic load can accelerate the early union of allograft-host bone interface and later new bone creep substitution to the necrotic allograft.
基金supported by the Australian Research Council(ARC)through Discovery Project(DP 140102581)LIEF Grants(LE100100081 and LE110100099)
文摘Silicene, a new allotrope of silicon in a twodimensional honeycomb structure, has attracted intensive research interest due to its novel physical and chemical properties. Unlike carbon atoms in graphene, silicon atoms prefer to adopt sp2/sp3-hybridized state in silicene,enhancing chemical activity on the surface and allowing tunable electronic states by chemical functionalization. The silicene monolayers epitaxially grown on Ag(111) surfaces demonstrate various reconstructions with different electronic structures. In this article, the structure, phonon modes, electronic properties, and chemical properties of silicene are reviewed based on theoretical and experimental works in recent years.
文摘Objective: To observe the survival of hand allograft under the state of immunosuppression and the pathological changes of rejection in the recovery process. Methods: The biopsies of the skin, nerve, muscle, tendon and bone tissue of hand allografts during different stages from 1 day to 7 months after operation were observed using routine histological technique. Results: No significant changes due to rejection in skin, nerve, muscle and bone tissue were observed. But different degrees of weak rejective changes were found on the wall of blood vessels; in the muscle and nerve the reactions were markedly stronger than those found in skin tissues. Conclusions: The rejection in deep tissues should be monitored in controlling the rejection of hand allograft.
基金Supported by the National Natural Science Foundation of China under Grant No.11205120
文摘Configuration-constrained calculations of potential-energy surfaces for ^292 122 show the occurrence of multiquasiparticle high-K isomeric state at oblate superdeformation. Such state could play a unique role in superheavy nuclei, with possible long life time from enhanced difficulty in fission due to additional barrier at oblate deformation, retardation in a decay due to unpaired nucleons, and hindrance in γ-ray transition due to K forbiddenness.
