AIM:To evaluate the efficacy and safety of baclofen for treatment of refractory gastroesophageal reflux-induced chronic cough (GERC) unresponsive to standard anti-reflux therapy. METHODS:Sixteen patients with refracto...AIM:To evaluate the efficacy and safety of baclofen for treatment of refractory gastroesophageal reflux-induced chronic cough (GERC) unresponsive to standard anti-reflux therapy. METHODS:Sixteen patients with refractory GERC were given an 8-wk course of baclofen 20 mg three times a day as an add-on therapy to omeprazole. Changes in the cough symptom score, cough threshold to capsaicin, reflux symptom score and possible adverse effects were determined after treatment. The variables of multi-channel intraluminal impedance combined with pH monitoring were compared between responders and non-responders to baclofen. RESULTS:Twelve of 16 patients completed treatment. Cough disappeared or improved in 56.3% (9/16)of patients, including 6 patients with acid refluxinduced cough (66.7%) and 3 patients with non-acid reflux-induced cough (33.3%). With baclofen treatment, the cough symptom score began to decrease at week 2, was clearly decreased at week 6 and reached a minimum at week 8. At the end of therapy, the lowest concentration of capsaicin required for induction of ≥ 2 and ≥ 5 coughs increased from 0.98 (1.46) to 1.95 (6.82) μmol/L (Z = -2.281, P = 0.024) and from 1.95 (7.31) to 7.8 (13.65) μmol/L (Z = -2.433, P = 0.014), respectively, and the reflux symptom score decreased from 8.0 ± 1.6 to 6.8 ± 0.8 (t = 2.454, P = 0.023). The number of acid reflux episodes was significantly lower in responders than in non-responders. The main adverse effects were somnolence, dizziness and fatigue. CONCLUSION:Baclofen is a useful, but suboptimal treatment option for refractory GERC.展开更多
Effects of Nb_(2)O_(5)dopant on the radiation response of barium gallo-germanate(BGG)glass are studied mainly by electron paramagnetic resonance and absorption spectroscopy.Owing to the Nb^(5+)$Nb^(3+)interconversion ...Effects of Nb_(2)O_(5)dopant on the radiation response of barium gallo-germanate(BGG)glass are studied mainly by electron paramagnetic resonance and absorption spectroscopy.Owing to the Nb^(5+)$Nb^(3+)interconversion in doped samples,formations of Ge-related non-bridging oxygen hole center and Ge-related electron center defects after g-ray irradiation are inhibited.Thereby,Nb_(2)O_(5)dopant can enhance radiation resistance of BGG glass,and 1.0%Nb2O5 concentration is the best.展开更多
The corrosion and passive behaviour of duplex stainless steel 2205 at six cooling rates (1, 5, 10, 15, 20 ℃ s^-1 and water quenched) in a simulated marine-environment solution was investigated using electrochemical...The corrosion and passive behaviour of duplex stainless steel 2205 at six cooling rates (1, 5, 10, 15, 20 ℃ s^-1 and water quenched) in a simulated marine-environment solution was investigated using electrochemical measurements of potentiostatic critical pitting temperature, potentiodynamic polarisation curves, electrochemical impedance spectroscopy and Mott-Schottky curves. The microstructural evolution and pitting morphologies of the specimens were visualised using an optical microscope and scanning electron microscope. The electrochemical responses of the passive film show that passivity of the steel was enhanced as the cooling rate increased; however, the threshold cooling rate was 20 ℃ s^-1, beyond which pitting corrosion resistance remained stable. Based on the analyses of microstructural evolution and pit morphologies, the proportion of the ferrite phase increased with the cooling rate and the ratio of austenite and ferrite was close to 1:1. The pitting size decreased as the cooling rate increased, and most metastable pits on specimens were located in the ferrite phase and on the ferrite-austenite interface. Thus, pitting resistance of steel is governed by the phase that provides the lowest pitting resistance equivalent number. The optimised pitting corrosion resistance for steel 2205 was achieved when it was greater than or equal to 20℃ s^-1.展开更多
The influences of nitrogen content and austenitization temperature on Nb(C, N) precipitation in niobium micro-alloyed steels were studied by different methods: optical microscopy, tensile tests, scanning electron m...The influences of nitrogen content and austenitization temperature on Nb(C, N) precipitation in niobium micro-alloyed steels were studied by different methods: optical microscopy, tensile tests, scanning electron mi- croscopy, transmission electron microscopy, physicochemical phase analysis, and small-angle X-ray scattering. The results show that the strength of the steel with high nitrogen content is slightly higher than that of the steel with low nitrogen content. The increase in the nitrogen content does not result in the increase in the amount of Nb(C,N) precipitates, which mainly depends on the niobium content in the steel. The mass fraction of small-sized Nb(C, N) precipitates (1--10 nm) in the steel with high nitrogen content is less than that in the steel with low nitrogen con- tent. After austenitized at 1 150 ℃, a number of large cuboidal and needle-shaped particles are detected in the steel with high nitrogen content, whereas they dissolve after austenitized at 1 200 ℃ and the Nb(C,N) precipitates become finer in both steels. Furthermore, the results also show that part of the nitrogen in steel involves the formation of al- loyed cementite.展开更多
基金Supported by National Natural Science Foundation of China, No. 81170079Shanghai Shenkang Hospital Development Center Project, No. SHDC12012211
文摘AIM:To evaluate the efficacy and safety of baclofen for treatment of refractory gastroesophageal reflux-induced chronic cough (GERC) unresponsive to standard anti-reflux therapy. METHODS:Sixteen patients with refractory GERC were given an 8-wk course of baclofen 20 mg three times a day as an add-on therapy to omeprazole. Changes in the cough symptom score, cough threshold to capsaicin, reflux symptom score and possible adverse effects were determined after treatment. The variables of multi-channel intraluminal impedance combined with pH monitoring were compared between responders and non-responders to baclofen. RESULTS:Twelve of 16 patients completed treatment. Cough disappeared or improved in 56.3% (9/16)of patients, including 6 patients with acid refluxinduced cough (66.7%) and 3 patients with non-acid reflux-induced cough (33.3%). With baclofen treatment, the cough symptom score began to decrease at week 2, was clearly decreased at week 6 and reached a minimum at week 8. At the end of therapy, the lowest concentration of capsaicin required for induction of ≥ 2 and ≥ 5 coughs increased from 0.98 (1.46) to 1.95 (6.82) μmol/L (Z = -2.281, P = 0.024) and from 1.95 (7.31) to 7.8 (13.65) μmol/L (Z = -2.433, P = 0.014), respectively, and the reflux symptom score decreased from 8.0 ± 1.6 to 6.8 ± 0.8 (t = 2.454, P = 0.023). The number of acid reflux episodes was significantly lower in responders than in non-responders. The main adverse effects were somnolence, dizziness and fatigue. CONCLUSION:Baclofen is a useful, but suboptimal treatment option for refractory GERC.
基金supported by China National Funds for Guangdong Key Research and Development Program(Grant No.2018B090904001)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(Grant No.2017BT01X137)+2 种基金Key Laboratory of Laser Device Technology Foundation of China Ordnance Industry Group Co.(Grant No.KLLDT202010)the Key R&D Program of Guangzhou(Grant No.202007020003)the National Natural Science Foundation of China(Grant No.52002131)。
文摘Effects of Nb_(2)O_(5)dopant on the radiation response of barium gallo-germanate(BGG)glass are studied mainly by electron paramagnetic resonance and absorption spectroscopy.Owing to the Nb^(5+)$Nb^(3+)interconversion in doped samples,formations of Ge-related non-bridging oxygen hole center and Ge-related electron center defects after g-ray irradiation are inhibited.Thereby,Nb_(2)O_(5)dopant can enhance radiation resistance of BGG glass,and 1.0%Nb2O5 concentration is the best.
文摘The corrosion and passive behaviour of duplex stainless steel 2205 at six cooling rates (1, 5, 10, 15, 20 ℃ s^-1 and water quenched) in a simulated marine-environment solution was investigated using electrochemical measurements of potentiostatic critical pitting temperature, potentiodynamic polarisation curves, electrochemical impedance spectroscopy and Mott-Schottky curves. The microstructural evolution and pitting morphologies of the specimens were visualised using an optical microscope and scanning electron microscope. The electrochemical responses of the passive film show that passivity of the steel was enhanced as the cooling rate increased; however, the threshold cooling rate was 20 ℃ s^-1, beyond which pitting corrosion resistance remained stable. Based on the analyses of microstructural evolution and pit morphologies, the proportion of the ferrite phase increased with the cooling rate and the ratio of austenite and ferrite was close to 1:1. The pitting size decreased as the cooling rate increased, and most metastable pits on specimens were located in the ferrite phase and on the ferrite-austenite interface. Thus, pitting resistance of steel is governed by the phase that provides the lowest pitting resistance equivalent number. The optimised pitting corrosion resistance for steel 2205 was achieved when it was greater than or equal to 20℃ s^-1.
基金Item Sponsored by the CITIC-CBMM Niobium Steel Research and Development Program of China(2013-D065)
文摘The influences of nitrogen content and austenitization temperature on Nb(C, N) precipitation in niobium micro-alloyed steels were studied by different methods: optical microscopy, tensile tests, scanning electron mi- croscopy, transmission electron microscopy, physicochemical phase analysis, and small-angle X-ray scattering. The results show that the strength of the steel with high nitrogen content is slightly higher than that of the steel with low nitrogen content. The increase in the nitrogen content does not result in the increase in the amount of Nb(C,N) precipitates, which mainly depends on the niobium content in the steel. The mass fraction of small-sized Nb(C, N) precipitates (1--10 nm) in the steel with high nitrogen content is less than that in the steel with low nitrogen con- tent. After austenitized at 1 150 ℃, a number of large cuboidal and needle-shaped particles are detected in the steel with high nitrogen content, whereas they dissolve after austenitized at 1 200 ℃ and the Nb(C,N) precipitates become finer in both steels. Furthermore, the results also show that part of the nitrogen in steel involves the formation of al- loyed cementite.