钙调神经磷酸酶调节因子1(regulator of calcineurin 1,RCAN1)基因在人类21号染色体唐氏综合征关键区域被首次发现,主要在有颌脊椎动物表达,在无脊椎动物和真菌中也有少量表达。RCAN1在大脑、心、骨骼肌、肾和肠道等多种组织中差异表达...钙调神经磷酸酶调节因子1(regulator of calcineurin 1,RCAN1)基因在人类21号染色体唐氏综合征关键区域被首次发现,主要在有颌脊椎动物表达,在无脊椎动物和真菌中也有少量表达。RCAN1在大脑、心、骨骼肌、肾和肠道等多种组织中差异表达,在活性氧、Ca^(2+)、淀粉样蛋白β和激素等因素作用下持续表达。RCAN1与Ca^(2+)依赖的钙调磷酸酶(calcineurin,CN)结合抑制CN活性,调节重要底物的去磷酸化,参与线粒体稳态、昼夜节律、肥胖及产热等功能调节,在肿瘤、脑血管疾病、糖尿病等多种疾病中发挥了重要作用。近年来发现,RCAN1在心肌梗死、动脉粥样硬化、心脏瓣膜的形成等多方面发挥重要作用,可能是心血管疾病治疗的潜在靶点。展开更多
The microstructure and mechanical properties of Mg-10.1Gd-3.74Y-0.25Zr （mass fraction, %） alloy （GW104 alloy） cast by metal mould casting （MMC） and lost foam casting （LFC） were evaluated, respectively. It is r...The microstructure and mechanical properties of Mg-10.1Gd-3.74Y-0.25Zr （mass fraction, %） alloy （GW104 alloy） cast by metal mould casting （MMC） and lost foam casting （LFC） were evaluated, respectively. It is revealed that different forming modes do not influence the phase composition of as-cast alloy. In the as-cast specimens, the microstructures are similar and composed of α-Mg solid solution, eutectic compound of α-Mg＋Mg 24 （Gd, Y） 5 and cuboid-shaped Mg 5 （Gd, Y） phase; whereas the average grain size of the alloy produced by metal mould casting is smaller than that by lost foam casting. The eutectic compound of the alloy is completely dissolved after solution treatment at 525 ℃for 6 h, while the Mg 5 （Gd, Y） phase still exists after solution treatment. After peak-ageing, the lost foam cast alloy exhibits the maximum ultimate tensile strength of 285 MPa, and metal mould cast specimen 325 MPa at room temperature, while the tensile yield strengths of them are comparable. It can be concluded that GW104 alloy cast by lost foam casting possesses similar microstructure and evidently lower mechanical strength compared with metal mould cast alloy, due to slow solidification rate and proneness to form shrinkage porosities during lost foam casting process.展开更多
文摘钙调神经磷酸酶调节因子1(regulator of calcineurin 1,RCAN1)基因在人类21号染色体唐氏综合征关键区域被首次发现,主要在有颌脊椎动物表达,在无脊椎动物和真菌中也有少量表达。RCAN1在大脑、心、骨骼肌、肾和肠道等多种组织中差异表达,在活性氧、Ca^(2+)、淀粉样蛋白β和激素等因素作用下持续表达。RCAN1与Ca^(2+)依赖的钙调磷酸酶(calcineurin,CN)结合抑制CN活性,调节重要底物的去磷酸化,参与线粒体稳态、昼夜节律、肥胖及产热等功能调节,在肿瘤、脑血管疾病、糖尿病等多种疾病中发挥了重要作用。近年来发现,RCAN1在心肌梗死、动脉粥样硬化、心脏瓣膜的形成等多方面发挥重要作用,可能是心血管疾病治疗的潜在靶点。
基金Project(2007CB613704)supported by the National Basic Research Program of China
文摘The microstructure and mechanical properties of Mg-10.1Gd-3.74Y-0.25Zr （mass fraction, %） alloy （GW104 alloy） cast by metal mould casting （MMC） and lost foam casting （LFC） were evaluated, respectively. It is revealed that different forming modes do not influence the phase composition of as-cast alloy. In the as-cast specimens, the microstructures are similar and composed of α-Mg solid solution, eutectic compound of α-Mg＋Mg 24 （Gd, Y） 5 and cuboid-shaped Mg 5 （Gd, Y） phase; whereas the average grain size of the alloy produced by metal mould casting is smaller than that by lost foam casting. The eutectic compound of the alloy is completely dissolved after solution treatment at 525 ℃for 6 h, while the Mg 5 （Gd, Y） phase still exists after solution treatment. After peak-ageing, the lost foam cast alloy exhibits the maximum ultimate tensile strength of 285 MPa, and metal mould cast specimen 325 MPa at room temperature, while the tensile yield strengths of them are comparable. It can be concluded that GW104 alloy cast by lost foam casting possesses similar microstructure and evidently lower mechanical strength compared with metal mould cast alloy, due to slow solidification rate and proneness to form shrinkage porosities during lost foam casting process.
