Background:Rheumatoid arthritis(RA),a chronic systemic autoimmune disease,is characterized by synovitis and progressive damage to the bone and cartilage of the joints,leading to disability and reduced quality of life....Background:Rheumatoid arthritis(RA),a chronic systemic autoimmune disease,is characterized by synovitis and progressive damage to the bone and cartilage of the joints,leading to disability and reduced quality of life.This study was a randomized clinical trial comparing the outcomes between withdrawal and dose reduction of tofacitinib in patients with RA who achieved sustained disease control.Methods:The study was designed as a multicenter,open-label,randomized controlled trial.Eligible patients who were taking tofacitinib(5 mg twice daily)and had achieved sustained RA remission or low disease activity(disease activity score in 28 joints[DAS28]≤3.2)for at least 3 months were enrolled at six centers in Shanghai,China.Patients were randomly assigned(1:1:1)to one of three treatment groups:continuation of tofacitinib(5 mg twice daily);reduction in tofacitinib dose(5 mg daily);and withdrawal of tofacitinib.Efficacy and safety were assessed up to 6 months.Results:Overall,122 eligible patients were enrolled,with 41 in the continuation group,42 in the dose-reduction group,and 39 in the withdrawal group.After 6 months,the percentage of patients with a DAS28-erythrocyte sedimentation rate(ESR)of<3.2 was significantly lower in the withdrawal group than that in the reduction and continuation groups(20.5%,64.3%,and 95.1%,respectively;P<0.0001 for both comparisons).The average flare-free time was 5.8 months for the continuation group,4.7 months for the dose reduction group,and 2.4 months for the withdrawal group.Conclusion:Withdrawal of tofacitinib in patients with RA with stable disease control resulted in a rapid and significant loss of efficacy,while standard or reduced doses of tofacitinib maintained a favorable state.Trial Registration:Chictr.org,ChiCTR2000039799.展开更多
A novel method is proposed to extend the output power back-off(OPBO)range of the Doherty power amplifier(DPA).This study reveals that the OPBO range of the DPA can be extended by tuning the output impedance of the pea...A novel method is proposed to extend the output power back-off(OPBO)range of the Doherty power amplifier(DPA).This study reveals that the OPBO range of the DPA can be extended by tuning the output impedance of the peaking stage away from infinity and changing the phase delay of the output matching network of the carrier power amplifier.Based on this theory,a large-OPBO-range high-efficiency asymmetrical DPA working band from 1.55 to 2.2 GHz(35%relative bandwidth)is designed to verify the proposed method.Experimental results show that the DPA operates from 1.6 to 2.1 GHz.The range of the measured efficiency is 42.2%–52.1%in the OPBO state and 47%–62.7%in the saturation state.The OPBO range is 11.1–13.2 dB.展开更多
文摘Background:Rheumatoid arthritis(RA),a chronic systemic autoimmune disease,is characterized by synovitis and progressive damage to the bone and cartilage of the joints,leading to disability and reduced quality of life.This study was a randomized clinical trial comparing the outcomes between withdrawal and dose reduction of tofacitinib in patients with RA who achieved sustained disease control.Methods:The study was designed as a multicenter,open-label,randomized controlled trial.Eligible patients who were taking tofacitinib(5 mg twice daily)and had achieved sustained RA remission or low disease activity(disease activity score in 28 joints[DAS28]≤3.2)for at least 3 months were enrolled at six centers in Shanghai,China.Patients were randomly assigned(1:1:1)to one of three treatment groups:continuation of tofacitinib(5 mg twice daily);reduction in tofacitinib dose(5 mg daily);and withdrawal of tofacitinib.Efficacy and safety were assessed up to 6 months.Results:Overall,122 eligible patients were enrolled,with 41 in the continuation group,42 in the dose-reduction group,and 39 in the withdrawal group.After 6 months,the percentage of patients with a DAS28-erythrocyte sedimentation rate(ESR)of<3.2 was significantly lower in the withdrawal group than that in the reduction and continuation groups(20.5%,64.3%,and 95.1%,respectively;P<0.0001 for both comparisons).The average flare-free time was 5.8 months for the continuation group,4.7 months for the dose reduction group,and 2.4 months for the withdrawal group.Conclusion:Withdrawal of tofacitinib in patients with RA with stable disease control resulted in a rapid and significant loss of efficacy,while standard or reduced doses of tofacitinib maintained a favorable state.Trial Registration:Chictr.org,ChiCTR2000039799.
基金Project supported by the National Natural Science Founda-tion of China(Nos.62001061 and 62171068)the Science and Technology Research Program of Chongqing Municipal Educa-tion Commission(No.KJQN201900621)the Natural Science Foundation of Chongqing,China(No.cstc2020jcyj-msxmX0129)。
文摘A novel method is proposed to extend the output power back-off(OPBO)range of the Doherty power amplifier(DPA).This study reveals that the OPBO range of the DPA can be extended by tuning the output impedance of the peaking stage away from infinity and changing the phase delay of the output matching network of the carrier power amplifier.Based on this theory,a large-OPBO-range high-efficiency asymmetrical DPA working band from 1.55 to 2.2 GHz(35%relative bandwidth)is designed to verify the proposed method.Experimental results show that the DPA operates from 1.6 to 2.1 GHz.The range of the measured efficiency is 42.2%–52.1%in the OPBO state and 47%–62.7%in the saturation state.The OPBO range is 11.1–13.2 dB.
