目的对一个常染色体显性遗传的Van der Hoeve综合征家系进行详尽的临床表型分析及基因突变检测,明确该家系的致病基因突变位点及该突变对基因编码的影响。方法对收集到的Van der Hoeve综合征家系进行包括病史、体格检查及辅助检查在内...目的对一个常染色体显性遗传的Van der Hoeve综合征家系进行详尽的临床表型分析及基因突变检测,明确该家系的致病基因突变位点及该突变对基因编码的影响。方法对收集到的Van der Hoeve综合征家系进行包括病史、体格检查及辅助检查在内的临床资料的收集及外周血液样本的采集,并对22位家系成员进行外显子组测序以及Sanger测序,利用生物信息学软件分析数据。结果该家系共五代,各代连续发病,且每一代男女均可患病,符合常染色体显性遗传特点。该家系中12例患者均自出生时巩膜即呈蓝色且身材矮小,8例患者有骨折病史,可正常愈合,3例患者考虑有Van der Hoeve综合征所致的听力下降,12例患者的COL1A1基因第17号外显子有一个碱基的缺失(c.1128delT),使第376位后的氨基酸编码改变,在第539位提前结束氨基酸编码,该家系中10例无症状者无此突变。结论该家系患者确定为由COL1A1基因c.1128delT突变导致的Van der Hoeve综合征。展开更多
A metallic glass coating with the composition of Fe51.33Cr14.9Mo25.67Y3.4C3.44B1.26 (mole fraction, %) on the Q235 stainless steel was developed by the detonation gun (D-gun) spraying process. The microstructure a...A metallic glass coating with the composition of Fe51.33Cr14.9Mo25.67Y3.4C3.44B1.26 (mole fraction, %) on the Q235 stainless steel was developed by the detonation gun (D-gun) spraying process. The microstructure and the phase aggregate were analyzed by scanning electron microscopy and X-ray diffractometry, respectively. Microhardness, wear resistance and corrosion behavior were assessed using a Vickers microhardness tester, a ball-on-disk wear testing machine and the electrochemical measurement method, respectively. Microstructural studies show that the coatings possess a densely layered structure with the porosity less than 2.1%. The tribological behavior of the coatings examined under dry conditions shows that their relative wear resistance is five times higher than that of the substrate material. Both adhesive wear and abrasive wear contribute to the friction, but the former is the dominant wear mechanism of the metallic glass coatings. The coatings exhibit low passive current density and extremely wide passive region in 3.5% NaCl solution, thus indicating excellent corrosion resistance.展开更多
An interesting phenomenon of cooling-rate induced brittleness in Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glass (BMG) was reported. It was found that the as-cast BMG specimens exhibited a brittle-ductile transition w...An interesting phenomenon of cooling-rate induced brittleness in Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glass (BMG) was reported. It was found that the as-cast BMG specimens exhibited a brittle-ductile transition when the larger specimens were machined into smaller specimens through removing the cast-softening surface layer by layer. After compression tests, the as-machined small specimens, owing to the absence of the cast-softening surface, displayed highly dense and intersecting shear bands, and extensive plastic deformation. This is in contrast to the catastrophic failure and low deformability in the as-cast large specimens. More free volume was detected in the smaller as-fractured specimens, by differential scanning calorimetry, which may be attributed to the occurrence of strain softening and increased plasticity. Compared with the relatively smooth fracture surface in the smaller specimens, the larger specimens showed more diverse features on the fracture surface due to their graded structures.展开更多
文摘目的对一个常染色体显性遗传的Van der Hoeve综合征家系进行详尽的临床表型分析及基因突变检测,明确该家系的致病基因突变位点及该突变对基因编码的影响。方法对收集到的Van der Hoeve综合征家系进行包括病史、体格检查及辅助检查在内的临床资料的收集及外周血液样本的采集,并对22位家系成员进行外显子组测序以及Sanger测序,利用生物信息学软件分析数据。结果该家系共五代,各代连续发病,且每一代男女均可患病,符合常染色体显性遗传特点。该家系中12例患者均自出生时巩膜即呈蓝色且身材矮小,8例患者有骨折病史,可正常愈合,3例患者考虑有Van der Hoeve综合征所致的听力下降,12例患者的COL1A1基因第17号外显子有一个碱基的缺失(c.1128delT),使第376位后的氨基酸编码改变,在第539位提前结束氨基酸编码,该家系中10例无症状者无此突变。结论该家系患者确定为由COL1A1基因c.1128delT突变导致的Van der Hoeve综合征。
基金Project(51301205)supported by the National Natural Science Foundation of ChinaProject(20130162120001)supported by the Doctoral Program of Higher Education of China+2 种基金Project(K1502003-11)supported by the Changsha Municipal Major Science and Technology Program,ChinaProject(K1406012-11)supported by the Changsha Municipal Science and Technology Plan,ChinaProject(2016CX003)supported by the Innovation-driven Plan in Central South University,China
文摘A metallic glass coating with the composition of Fe51.33Cr14.9Mo25.67Y3.4C3.44B1.26 (mole fraction, %) on the Q235 stainless steel was developed by the detonation gun (D-gun) spraying process. The microstructure and the phase aggregate were analyzed by scanning electron microscopy and X-ray diffractometry, respectively. Microhardness, wear resistance and corrosion behavior were assessed using a Vickers microhardness tester, a ball-on-disk wear testing machine and the electrochemical measurement method, respectively. Microstructural studies show that the coatings possess a densely layered structure with the porosity less than 2.1%. The tribological behavior of the coatings examined under dry conditions shows that their relative wear resistance is five times higher than that of the substrate material. Both adhesive wear and abrasive wear contribute to the friction, but the former is the dominant wear mechanism of the metallic glass coatings. The coatings exhibit low passive current density and extremely wide passive region in 3.5% NaCl solution, thus indicating excellent corrosion resistance.
基金Project(2012M511401)supported by China Postdoctoral Science FoundationProject(12JJ5018)supported by Hunan Provincial Natural Science Foundation of China+1 种基金Project(2012RS4006)supported by Hunan Provincial Science and Technology Plan of ChinaProject(CSUZC2012028)supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,China
文摘An interesting phenomenon of cooling-rate induced brittleness in Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glass (BMG) was reported. It was found that the as-cast BMG specimens exhibited a brittle-ductile transition when the larger specimens were machined into smaller specimens through removing the cast-softening surface layer by layer. After compression tests, the as-machined small specimens, owing to the absence of the cast-softening surface, displayed highly dense and intersecting shear bands, and extensive plastic deformation. This is in contrast to the catastrophic failure and low deformability in the as-cast large specimens. More free volume was detected in the smaller as-fractured specimens, by differential scanning calorimetry, which may be attributed to the occurrence of strain softening and increased plasticity. Compared with the relatively smooth fracture surface in the smaller specimens, the larger specimens showed more diverse features on the fracture surface due to their graded structures.