In order to investigate the real-time cracking behavior of each component of a composite with strong interfacial bonding among lamellae, Ti-18 Nb(at.%) composite was prepared by spark plasma sintering(SPS), followed b...In order to investigate the real-time cracking behavior of each component of a composite with strong interfacial bonding among lamellae, Ti-18 Nb(at.%) composite was prepared by spark plasma sintering(SPS), followed by hot-rolling, annealing, and quenching. The microstructure and mechanical properties were characterized by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), micro-region X-ray diffractometry(MRXRD), nanoindentation, and in-situ scanning electron microscopy tensile testing. The results show that the Ti-18 Nb consists of Ti-enriched, diffusion and Nb-enriched zones, and the sharp Nb gradient across different zones leads to inhomogeneous distribution of phase and mechanical properties. A remarkable finding is that the diffusion zones not only enable the cooperative deformation between the brittle Ti-enriched zones and the ductile Nb-enriched zones but also act as the crack-arresters to prevent the local cracks in the Ti-enriched zones from further propagating across the composite.展开更多
We aimed to explore the diagnosis and treatment of peripheral primitive neuroectodermal tumors （pPNETs）. We retrospectively analyzed the diagnosis and treatment process of a patient who was diagnosed with pPNETs by ...We aimed to explore the diagnosis and treatment of peripheral primitive neuroectodermal tumors （pPNETs）. We retrospectively analyzed the diagnosis and treatment process of a patient who was diagnosed with pPNETs by pathology. This case was a man with soft masses arising from the left chest wall near the armpit and left supraclavicular of a 47-year-old man. The patient mainly presented with the masses which increasing gradually with obvious pain. Needle biopsy showed that they were both metastatic adenocaroinoma. Ultrasonography B revealed blood flow of these two low density placeholders can be seen in the signal, not oppression axillary and vein. Radical resection of the masses were performed. Histopathologic study and immunohistochemistry （IHC） confirmed the masses to be peripheral primitive neuroectodermal tumors, pPNETs is a rare malignant small round cell tumor. CT and MRI examination can estimate the resectability of the tumor; Ultrasound B can make sure its inside blood supply and the positional relationship between the mass and the surrounding vasculature. The diagnosis of pPNETs is based primarily on histopathologic study and IHC, especially those with the characteristics of the Homer-Wright and neuroendocrine markers. Radical resection of the tumor is the most effective therapeutic method. The effect of adjuvant chemo-radiation is worth affirmation. Autologous stem cell rescue besides adjuvant chemotherapy has been associated with prolonged survival.展开更多
Objective： To testify the effect of the stem cells derived from the widely distributed fat tissue on repairing full-thickness hyaline cartilage defects. Methods： Adipose-derived stem cells （ADSCs） were derived fro...Objective： To testify the effect of the stem cells derived from the widely distributed fat tissue on repairing full-thickness hyaline cartilage defects. Methods： Adipose-derived stem cells （ADSCs） were derived from adipose tissue and cultured in vitro. Twenty- seven New Zealand white rabbits were divided into three groups randomly. The cultured ADSCs mixed with calcium alginate gel were used to fill the full-thickness hyaline cartilage defects created at the patellafemoral joint, and the defects repaired with gel or without treatment served as control groups. After 4, 8 and 12 weeks, the reconstructed tissue was evaluated macroscopically and microscopically. Histological analysis and qualitative scoring were also performed to detect the outcome.Results： Full thickness hyaline cartilage defects were repaired completely with ADSCs-derived tissue. The result was better in ADSCs group than the control ones. The microstructure of reconstructed tissue with ADSCs was similar to that of hyaline cartilage and contained more cells and regular matrix fibers, being better than other groups. Plenty of collagen fibers around cells could be seen under transmission electron microscopy. Statistical analysis revealed a significant difference in comparison with other groups at each time point （t=4.360, P〈0.01）. Conclusion： These results indicate that stem cells derived from mature adipose without induction possess the ability to repair cartilage defects展开更多
基金Project(51625404)supported by the National Natural Science Foundation for Distinguished Young Scholar of ChinaProjects(51604104,51504295)supported by the National Natural Science Foundation of China
文摘In order to investigate the real-time cracking behavior of each component of a composite with strong interfacial bonding among lamellae, Ti-18 Nb(at.%) composite was prepared by spark plasma sintering(SPS), followed by hot-rolling, annealing, and quenching. The microstructure and mechanical properties were characterized by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), micro-region X-ray diffractometry(MRXRD), nanoindentation, and in-situ scanning electron microscopy tensile testing. The results show that the Ti-18 Nb consists of Ti-enriched, diffusion and Nb-enriched zones, and the sharp Nb gradient across different zones leads to inhomogeneous distribution of phase and mechanical properties. A remarkable finding is that the diffusion zones not only enable the cooperative deformation between the brittle Ti-enriched zones and the ductile Nb-enriched zones but also act as the crack-arresters to prevent the local cracks in the Ti-enriched zones from further propagating across the composite.
文摘We aimed to explore the diagnosis and treatment of peripheral primitive neuroectodermal tumors （pPNETs）. We retrospectively analyzed the diagnosis and treatment process of a patient who was diagnosed with pPNETs by pathology. This case was a man with soft masses arising from the left chest wall near the armpit and left supraclavicular of a 47-year-old man. The patient mainly presented with the masses which increasing gradually with obvious pain. Needle biopsy showed that they were both metastatic adenocaroinoma. Ultrasonography B revealed blood flow of these two low density placeholders can be seen in the signal, not oppression axillary and vein. Radical resection of the masses were performed. Histopathologic study and immunohistochemistry （IHC） confirmed the masses to be peripheral primitive neuroectodermal tumors, pPNETs is a rare malignant small round cell tumor. CT and MRI examination can estimate the resectability of the tumor; Ultrasound B can make sure its inside blood supply and the positional relationship between the mass and the surrounding vasculature. The diagnosis of pPNETs is based primarily on histopathologic study and IHC, especially those with the characteristics of the Homer-Wright and neuroendocrine markers. Radical resection of the tumor is the most effective therapeutic method. The effect of adjuvant chemo-radiation is worth affirmation. Autologous stem cell rescue besides adjuvant chemotherapy has been associated with prolonged survival.
基金This work was funded by the National Natural Science Foundation of China （No. 30801167）.
文摘Objective： To testify the effect of the stem cells derived from the widely distributed fat tissue on repairing full-thickness hyaline cartilage defects. Methods： Adipose-derived stem cells （ADSCs） were derived from adipose tissue and cultured in vitro. Twenty- seven New Zealand white rabbits were divided into three groups randomly. The cultured ADSCs mixed with calcium alginate gel were used to fill the full-thickness hyaline cartilage defects created at the patellafemoral joint, and the defects repaired with gel or without treatment served as control groups. After 4, 8 and 12 weeks, the reconstructed tissue was evaluated macroscopically and microscopically. Histological analysis and qualitative scoring were also performed to detect the outcome.Results： Full thickness hyaline cartilage defects were repaired completely with ADSCs-derived tissue. The result was better in ADSCs group than the control ones. The microstructure of reconstructed tissue with ADSCs was similar to that of hyaline cartilage and contained more cells and regular matrix fibers, being better than other groups. Plenty of collagen fibers around cells could be seen under transmission electron microscopy. Statistical analysis revealed a significant difference in comparison with other groups at each time point （t=4.360, P〈0.01）. Conclusion： These results indicate that stem cells derived from mature adipose without induction possess the ability to repair cartilage defects
