AIM: To demonstrate the changes in ultrastructure and histopathology of the cornea in acute corneal alkaline burns after femtosecond laser-assisted deep lamellar keratoplasty.·METHODS: The New Zealand white rabbi...AIM: To demonstrate the changes in ultrastructure and histopathology of the cornea in acute corneal alkaline burns after femtosecond laser-assisted deep lamellar keratoplasty.·METHODS: The New Zealand white rabbits treated with alkaline corneal burn were randomized into two groups,Group A(16 eyes) with femtosecond laser-assisted deep lamellar keratoplasty 24 h after burn and Group B(16 eyes)without keratoplasty as controls. All eyes were evaluated with transmission electron microscopy(TEM) at 1, 2, 3,and 4wk follow-up, then all corneas were tested by hematoxylin and eosin staining histology.· RESULTS: The corneal grafts in Group A were transparent, while those in Group B showed corneal stromal edema and loosely arranged collagen fibers. One week after treatment, TEM revealed the intercellular desmosomes in the epithelial layers and intact non-dissolving nuclei in Group A. At week 4, the center of the corneas in Group A was transparent with regularly arranged collagen fibers and fibroblasts in the stroma. In Group B, squamous cells were observed on the corneal surface and some epithelial cells were detached.· CONCLUSION: Femtosecond laser-assisted deep lamellar keratoplasty can suppress inflammatory responses, prevent toxic substance-induced injury to the corneal endothelium and inner tissues with quicker recovery and better visual outcomes.展开更多
Martensitic stabilization caused by deformation in a TiNi shape memory alloy was studied.Special attention was paid to the deformed microstructures to identify the cause of martensitic stabilization.Martensitic stabil...Martensitic stabilization caused by deformation in a TiNi shape memory alloy was studied.Special attention was paid to the deformed microstructures to identify the cause of martensitic stabilization.Martensitic stabilization was demonstrated by differential scanning calorimetry for the tensioned TiNi shape memory alloy.Transmission electron microscopy revealed that antiphase boundaries were formed because of the fourfold dissociation of [110]B19' super lattice dislocations and were preserved after reverse transformation due to the lattice correspondence.Martensitic stabilization was attributed to dislocations induced by deformation,which reduced the ordering degree of the microstructure,spoiled the reverse path from martensite to parent phase compared with thermoelastic transformation,and imposed resistance on phase transformation through the stress field.展开更多
基金Supported by the Military Medical Science and Technology General Project During the 12thFive-Year Plan Period(No.CWS11J239)Autonomous Region of Xinjiang the Mandatory Project of Science and Technology(No.201491171)
文摘AIM: To demonstrate the changes in ultrastructure and histopathology of the cornea in acute corneal alkaline burns after femtosecond laser-assisted deep lamellar keratoplasty.·METHODS: The New Zealand white rabbits treated with alkaline corneal burn were randomized into two groups,Group A(16 eyes) with femtosecond laser-assisted deep lamellar keratoplasty 24 h after burn and Group B(16 eyes)without keratoplasty as controls. All eyes were evaluated with transmission electron microscopy(TEM) at 1, 2, 3,and 4wk follow-up, then all corneas were tested by hematoxylin and eosin staining histology.· RESULTS: The corneal grafts in Group A were transparent, while those in Group B showed corneal stromal edema and loosely arranged collagen fibers. One week after treatment, TEM revealed the intercellular desmosomes in the epithelial layers and intact non-dissolving nuclei in Group A. At week 4, the center of the corneas in Group A was transparent with regularly arranged collagen fibers and fibroblasts in the stroma. In Group B, squamous cells were observed on the corneal surface and some epithelial cells were detached.· CONCLUSION: Femtosecond laser-assisted deep lamellar keratoplasty can suppress inflammatory responses, prevent toxic substance-induced injury to the corneal endothelium and inner tissues with quicker recovery and better visual outcomes.
文摘Martensitic stabilization caused by deformation in a TiNi shape memory alloy was studied.Special attention was paid to the deformed microstructures to identify the cause of martensitic stabilization.Martensitic stabilization was demonstrated by differential scanning calorimetry for the tensioned TiNi shape memory alloy.Transmission electron microscopy revealed that antiphase boundaries were formed because of the fourfold dissociation of [110]B19' super lattice dislocations and were preserved after reverse transformation due to the lattice correspondence.Martensitic stabilization was attributed to dislocations induced by deformation,which reduced the ordering degree of the microstructure,spoiled the reverse path from martensite to parent phase compared with thermoelastic transformation,and imposed resistance on phase transformation through the stress field.