Objective To retrospectively investigate the clinical characteristics of sternal insufficiency fractures(SIFs) of post-menopausal women.Methods Findings on the clinical presentation,associated diseases,and imaging of ...Objective To retrospectively investigate the clinical characteristics of sternal insufficiency fractures(SIFs) of post-menopausal women.Methods Findings on the clinical presentation,associated diseases,and imaging of SIFs in 17 postmenopausal women admitted to our hospital between February 1999 and January 2009 were reported.Results Twelve patients complained of severe pain in their anterior chest.Other symptoms included cough(5 cases),dyspnoea(3 cases),breathlessness(3 cases),and wheeze(2 cases).Four patients had no discomfort.The sternums of 11 cases were tender to palpation.Seventeen patients had osteoporosis.Other associated diseases were chronic obstructive pulmonary disease(7 cases),rheumatoid arthritis(3 cases),systemic lupus erythematosus(1 case),asthma(1 case),and thoracic vertebral fracture(13 cases).Nine patients had received glucocorticoid treatment.The fractures were located in the body of the sternum in 15 patients,in the manubrium in 1 patient,and in the manubriosternal junction in 1 patient.Displaced fracture was present in 13 cases.Lateral radiography of the sternum showed a fracture line in 14 patients.In the remaining 3 cases,other imaging examinations such as bone scan,computed tomography or magnetic resonance imaging demonstrated the presence of a fracture.Conclusions Osteoporosis,glucocorticoid therapy,chronic obstructive pulmonary disease,and rheumatoid arthritis might be risk factors for SIFs.SIFs should be considered in the differential diagnosis of chest pain.展开更多
A novel ultrasonic-assisted low-temperature soldering was developed to join AZ31B Mg alloy and 6061 Al alloy with a series of Sn–x Zn solders. The average maximum shear strength of the joints reaches up to 87.5 MPa a...A novel ultrasonic-assisted low-temperature soldering was developed to join AZ31B Mg alloy and 6061 Al alloy with a series of Sn–x Zn solders. The average maximum shear strength of the joints reaches up to 87.5 MPa at soldering temperature of 300 °C under ultrasonic assistance for only 5 s using Sn–20 Zn solder. The fracture path propagates completely in the soldering seam. The results indicate that the microjet generated by ultrasonic pressure in liquid solder could strike and splinter the Mg_2Sn intermetallic compounds into small pieces, which contributes to the enhancement of the joint strength. In addition, the primary Al(Zn) solid solution phase formed during cooling stage could also strengthen the joint due to the prevention of microcracks propagation.展开更多
文摘Objective To retrospectively investigate the clinical characteristics of sternal insufficiency fractures(SIFs) of post-menopausal women.Methods Findings on the clinical presentation,associated diseases,and imaging of SIFs in 17 postmenopausal women admitted to our hospital between February 1999 and January 2009 were reported.Results Twelve patients complained of severe pain in their anterior chest.Other symptoms included cough(5 cases),dyspnoea(3 cases),breathlessness(3 cases),and wheeze(2 cases).Four patients had no discomfort.The sternums of 11 cases were tender to palpation.Seventeen patients had osteoporosis.Other associated diseases were chronic obstructive pulmonary disease(7 cases),rheumatoid arthritis(3 cases),systemic lupus erythematosus(1 case),asthma(1 case),and thoracic vertebral fracture(13 cases).Nine patients had received glucocorticoid treatment.The fractures were located in the body of the sternum in 15 patients,in the manubrium in 1 patient,and in the manubriosternal junction in 1 patient.Displaced fracture was present in 13 cases.Lateral radiography of the sternum showed a fracture line in 14 patients.In the remaining 3 cases,other imaging examinations such as bone scan,computed tomography or magnetic resonance imaging demonstrated the presence of a fracture.Conclusions Osteoporosis,glucocorticoid therapy,chronic obstructive pulmonary disease,and rheumatoid arthritis might be risk factors for SIFs.SIFs should be considered in the differential diagnosis of chest pain.
基金supported financially by the State Key Laboratory of Advanced Brazing Filler Metals & Technology (No. SKLABFMT-2016-02)the CAST Innovation Fund Key Project and the National Natural Science Foundation of China (Nos. 51775299 and 51520105007)
文摘A novel ultrasonic-assisted low-temperature soldering was developed to join AZ31B Mg alloy and 6061 Al alloy with a series of Sn–x Zn solders. The average maximum shear strength of the joints reaches up to 87.5 MPa at soldering temperature of 300 °C under ultrasonic assistance for only 5 s using Sn–20 Zn solder. The fracture path propagates completely in the soldering seam. The results indicate that the microjet generated by ultrasonic pressure in liquid solder could strike and splinter the Mg_2Sn intermetallic compounds into small pieces, which contributes to the enhancement of the joint strength. In addition, the primary Al(Zn) solid solution phase formed during cooling stage could also strengthen the joint due to the prevention of microcracks propagation.
