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Lifestyle improvement and the reduced risk of cardiovascular disease:the China-PAR project
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作者 Ying-Ying JIANG Fang-Chao liu +16 位作者 Chong SHEN Jian-Xin LI Ke-Yong HUANG Xue-Li YANG Ji-Chun CHEN xiao-qing liu Jie CAO Shu-Feng CHEN Ling YU Ying-Xin ZHAO Xian-Ping WU Lian-Cheng ZHAO Ying LI Dong-Sheng HU Jian-Feng HUANG Xiang-Feng LU Dong-Feng GU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第11期779-787,共9页
BACKGROUND The benefits of healthy lifestyles are well recognized. However, the extent to which improving unhealthy lifestyles reduces cardiovascular disease(CVD) risk needs to be discussed. We evaluated the impact of... BACKGROUND The benefits of healthy lifestyles are well recognized. However, the extent to which improving unhealthy lifestyles reduces cardiovascular disease(CVD) risk needs to be discussed. We evaluated the impact of lifestyle improvement on CVD incidence using data from the China-PAR project(Prediction for Atherosclerotic Cardiovascular Disease Risk in China).METHODS A total of 12,588 participants free of CVD were followed up for three visits after the baseline examination. Changes in four lifestyle factors(LFs)(smoking, diet, physical activity, and alcohol consumption) were assessed through questionnaires from the baseline to the first follow-up visit. Cox proportional hazard models were used to estimate hazard ratios(HRs) and corresponding 95% confidence intervals(CIs). The risk advancement periods(RAPs: the age difference between exposed and unexposed participants reaching the same incident CVD risk) and population-attributable risk percentage(PAR%) were also calculated.RESULTS A total of 909 incident CVD cases occurred over a median follow-up of 11.14 years. Compared with maintaining 0-1healthy LFs, maintaining 3–4 healthy LFs was associated with a 40% risk reduction of incident CVD(HR = 0.60, 95% CI: 0.45–0.79)and delayed CVD risk by 6.31 years(RAP:-6.31 [-9.92,-2.70] years). The PAR% of maintaining 3–4 unhealthy LFs was 22.0%compared to maintaining 0-1 unhealthy LFs. Besides, compared with maintaining two healthy LFs, improving healthy LFs from 2to 3–4 was associated with a 23% lower risk of CVD(HR = 0.77, 95% CI: 0.60–0.98).CONCLUSIONS Long-term sustenance of healthy lifestyles or improving unhealthy lifestyles can reduce and delay CVD risk. 展开更多
关键词 HAZARD maintaining ALCOHOL
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活血散结中药复方含药血浆对PDGF干预下兔RPE细胞增殖的影响 被引量:3
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作者 吴权龙 刘晓清 +4 位作者 彭俊 张又玮 潘坤 李建超 彭清华 《国际眼科杂志》 CAS 北大核心 2018年第9期1572-1577,共6页
目的:观察活血散结中药复方含药血浆对血小板源性生长因子(platelet derived growth factor,PDGF)干预下兔RPE细胞增殖的影响。方法:酶消化法获取RPE原代细胞,进行RPE细胞的原代培养和传代;制备活血散结中药复方含药血浆;选取第4代兔RP... 目的:观察活血散结中药复方含药血浆对血小板源性生长因子(platelet derived growth factor,PDGF)干预下兔RPE细胞增殖的影响。方法:酶消化法获取RPE原代细胞,进行RPE细胞的原代培养和传代;制备活血散结中药复方含药血浆;选取第4代兔RPE细胞为实验细胞,PDGF低、中、高剂量(5、10、20μg/L)干预48h后,CCK-8法检测并选取适宜细胞实验干预浓度;建立PDGF干预下RPE细胞增殖模型。实验分组为空白对照组(DMEM)、正常血浆组、PDGF(10μg/L)组、PDGF(10μg/L)+AG1296(10μmol/L)组、PDGF(10μg/L)+10%含药血浆组,PDGF(10μg/L)+20%含药血浆组,分别加入相应处理因素干预24h后,Transwell法测定兔RPE细胞迁移力;而干预48h后,CCK-8法测定兔RPE细胞的细胞活力OD值。结果:10%和20%浓度的活血散结中药复方含药血浆能有效抑制PDGF干预下RPE细胞的细胞活力、细胞迁移。结论:活血散结中药复方含药血浆能够抑制PDGF干预下兔RPE细胞增殖,这可能是其有效治疗增殖性玻璃体视网膜病变的机制之一。 展开更多
关键词 活血散结中药复方 含药血浆 视网膜色素上皮细胞 血小板源性生长因子 细胞活力 细胞迁移力
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SS-OCT检测PACG患者视网膜神经纤维层厚度及视盘参数的价值 被引量:1
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作者 沈婷 程瑜 +2 位作者 杨子建 刘晓庆 沈玺 《国际眼科杂志》 CAS 北大核心 2018年第9期1652-1655,共4页
目的:探讨扫频源光学相干层析成像(SS-OCT)技术检测视网膜神经纤维层(RNFL)厚度及视盘参数在原发性闭角型青光眼(PACG)疗效评价中的应用价值。方法:选择接受周边虹膜切开术、小梁切除术治疗的PACG患者60例68眼,根据术后2mo后的眼压情况... 目的:探讨扫频源光学相干层析成像(SS-OCT)技术检测视网膜神经纤维层(RNFL)厚度及视盘参数在原发性闭角型青光眼(PACG)疗效评价中的应用价值。方法:选择接受周边虹膜切开术、小梁切除术治疗的PACG患者60例68眼,根据术后2mo后的眼压情况将患者分为控制组(<21mmHg,39例45眼)和未控制组(≥21mmHg,21例23眼)。采用SS-OCT检测两组患者治疗前和治疗后6mo RNFL厚度及视盘参数,评价治疗效果。结果:治疗后,两组患者眼压均明显降低,且控制组明显低于未控制组(P<0.05)。治疗后,控制组患者各RNFL厚度均较治疗前无明显差异(P>0.05),而未控制组则明显变薄,与控制组比较差异均有统计学意义(P<0.05)。治疗后,未控制组患者视盘面积(DA)明显增大,盘沿面积(RA)、盘沿容积(RV)明显减小(P<0.05),控制组患者各视盘参数均明显优于未控制组(P<0.05)。眼压与视盘参数DA呈正相关,与RA呈负相关(r=0.415、-0.399,均P<0.05)。结论:SS-OCT可准确反映PACG患者眼压控制后RNFL厚度与视盘参数的变化,对于PACG病情追踪及疗效评估具有一定的临床价值。 展开更多
关键词 原发性闭角型青光眼 扫频源光学相干层析成像 视盘 视网膜神经纤维层厚度 疗效评价
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玻璃酸钠联合rhEGF滴眼液治疗白内障术后干眼疗效的Meta分析 被引量:7
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作者 黄雨 李洁 +4 位作者 刘晓清 黎冬冬 陈立浩 彭俊 彭清华 《国际眼科杂志》 CAS 北大核心 2021年第5期847-853,共7页
目的:运用Meta分析方法系统评价近5a玻璃酸钠联合重组人表皮生长因子(rhEGF)滴眼液治疗白内障术后干眼的疗效。方法:计算机检索2015-01/2020-05中国知网数据库、万方数据库、重庆维普中文科技期刊全文数据库、中国生物医学文献数据库(C... 目的:运用Meta分析方法系统评价近5a玻璃酸钠联合重组人表皮生长因子(rhEGF)滴眼液治疗白内障术后干眼的疗效。方法:计算机检索2015-01/2020-05中国知网数据库、万方数据库、重庆维普中文科技期刊全文数据库、中国生物医学文献数据库(CBM)、Cochrane Library、PudMed、MEDLINE等数据库关于采用玻璃酸钠联合rhEGF滴眼液治疗白内障术后干眼的的临床对照研究相关文献,使用Rev-man 5.3统计软件进行Meta分析和统计处理。结果:共纳入14项随机对照研究,患眼1529例。其中14项研究在治疗结束后进行了角膜荧光素染色(FL)评分,结果显示差异有统计学意义[MD=-0.86,95%CI(-1.07~-0.66),P<0.00001];14项研究在治疗结束后进行了泪膜破裂时间(BUT)测定,结果显示差异有统计学意义[MD=2.33,95%CI(1.64~3.03),P<0.00001];12项研究在治疗结束后进行了泪液分泌试验(SⅠt)测定,结果显示差异无统计学意义[MD=0.49,95%CI(-0.52~1.50),P=0.34];12项研究在治疗结束后进行了总体有效率计算,结果显示差异有统计学意义[OR=4.88,95%CI(3.34~7.14),P<0.00001];4项研究在治疗结束后进行了干眼症状评分测定,结果显示差异有统计学意义[MD=-1.09,95%CI(-1.58~-0.61),P<0.00001]。结论:玻璃酸钠联合rhEGF滴眼液治疗白内障术后干眼能显著提高角膜修复能力和BUT,在治疗白内障术后干眼总体疗效上更具优势。 展开更多
关键词 玻璃酸钠滴眼液 重组人表皮生长因子滴眼液 白内障术后干眼 META分析
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Epidemiology of Hepatitis B and Associated Liver Diseases in China 被引量:16
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作者 Yao Zhang Hua Zhang +1 位作者 Au Elizabeth xiao-qing liu 《Chinese Medical Sciences Journal》 CAS CSCD 2012年第4期243-248,共6页
Hepatitis B virus (HBV) infection has long been a critical public health challenge in China. National surveys revealed a prevalence of approximate 10% for chronic HBV infection in general population. HBV has been the ... Hepatitis B virus (HBV) infection has long been a critical public health challenge in China. National surveys revealed a prevalence of approximate 10% for chronic HBV infection in general population. HBV has been the leading cause of chronic hepatitis, cirrhosis, and liver cancers in Chinese population and a common pathogen of acute viral hepatitis. Meanwhile, the epidemic provided important opportunities to research the natural history, public health impact, and therapeutic and preventive interventions for HBV in China. In this review, we summarized the selected key epidemiological studies since 1970s regarding HBV infection and its associated liver diseases in China, and provided considerations for future research, prevention and treatment of HBV. 展开更多
关键词 乙型肝炎病毒 中国人群 肝脏疾病 流行病学 B型 病毒感染 慢性肝炎 病毒性肝炎
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Ginsenoside Rg1 protects against neurodegeneration by inducing neurite outgrowth in cultured hippocampal neurons 被引量:9
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作者 Liang Huang Li-feng liu +4 位作者 Juan liu Ling Dou Ge-ying Wang xiao-qing liu Qiong-lan Yuan 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第2期319-325,共7页
Ginsenoside Rg1(Rg1) has anti-aging and anti-neurodegenerative effects. However, the mechanisms underlying these actions remain unclear. The aim of the present study was to determine whether Rg1 affects hippocampal ... Ginsenoside Rg1(Rg1) has anti-aging and anti-neurodegenerative effects. However, the mechanisms underlying these actions remain unclear. The aim of the present study was to determine whether Rg1 affects hippocampal survival and neurite outgrowth in vitro after exposure to amyloid-beta peptide fragment 25–35(Aβ_(25–35)), and to explore whether the extracellular signal-regulated kinase(ERK) and Akt signaling pathways are involved in these biological processes. We cultured hippocampal neurons from newborn rats for 24 hours, then added Rg1 to the medium for another 24 hours, with or without pharmacological inhibitors of the mitogen-activated protein kinase(MAPK) family or Akt signaling pathways for a further 24 hours. We then immunostained the neurons for growth associated protein-43, and measured neurite length. In a separate experiment, we exposed cultured hippocampal neurons to Aβ_(25–35) for 30 minutes, before adding Rg1 for 48 hours, with or without Akt or MAPK inhibitors, and assessed neuronal survival using Hoechst 33258 staining, and phosphorylation of ERK1/2 and Akt by western blot analysis. Rg1 induced neurite outgrowth, and this effect was blocked by API-2(Akt inhibitor) and PD98059(MAPK/ERK kinase inhibitor), but not by SP600125 or SB203580(inhibitors of c-Jun N-terminal kinase and p38 MAPK, respectively). Consistent with this effect, Rg1 upregulated the phosphorylation of Akt and ERK1/2; these effects were reversed by API-2 and PD98059, respectively. In addition, Rg1 significantly reversed Aβ_(25–35)-induced apoptosis; this effect was blocked by API-2 and PD98059, but not by SP600125 or SB203580. Finally, Rg1 significantly reversed the Aβ_(25–35)-induced decrease in Akt and ERK1/2 phosphorylation, but API-2 prevented this reversal. Our results indicate that Rg1 enhances neurite outgrowth and protects against Aβ_(25–35)-induced damage, and that its mechanism may involve the activation of Akt and ERK1/2 signaling. 展开更多
关键词 nerve regeneration ginsenoside Rgl neurite outgrowth Aft25 35 hippocampal neurons Akt MAPK apoptosis growth associatedprotein-43 Hoechst 33258 staining PD98059 API-2 neural regeneration
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Beneficial effects of moderate to vigorous physical activity on cardiovascular disease among Chinese adults 被引量:15
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作者 Qiong liu Fang-Chao liu +16 位作者 Ke-Yong HUANG Jian-Xin LI Xue-Li YANG Xin-Yan WANG Ji-Chun CHEN xiao-qing liu Jie CAO Chong SHEN Ling YU Fang-Hong LU Xian-Ping WU Lian-Cheng ZHAO Ying LI Dong-Sheng HU Xiang-Feng LU Jian-Feng HUANG Dong-Feng GU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第2期85-95,共11页
Background In China,lack of evidence remains a significant challenge for the national initiative to promote physical activity(PA).We aimed to quantify the beneficial effects of meeting or maintaining the recommended P... Background In China,lack of evidence remains a significant challenge for the national initiative to promote physical activity(PA).We aimed to quantify the beneficial effects of meeting or maintaining the recommended PA level[150 minutes per week(min/wk)of moderate PA or 75 min/wk of vigorous PA or an equivalent combination]on incident cardiovascular disease(CVD)among Chinese population.Methods We included 100,560 participants without history of CVD from three cohorts in the Prediction for Atherosclerotic Cardiovascular Disease Risk in China(China-PAR)project.Cox proportional hazards models were used to estimate hazard ratios(HRs)and 95%confidence intervals(CIs)for CVD events and its subtypes,including stroke,coronary heart disease,heart failure,and CVD death.Results During a median follow-up of 7.3 years(range:6–15 years),777,163 person-years and 4693 incident CVD events were observed.Compared with participants who were inactive at baseline,the multivariable adjusted HR(95%CI)of developing CVD was 0.74(0.69–0.79)for those who met recommended moderate to vigorous physical activity(MVPA)level at baseline.Furthermore,the risk of CVD incidence was reduced with increment of MVPA(Ptrend<0.001),and the HR(95%CI)of highly-active versus inactive category was 0.62(0.56–0.68).Compared with individuals who were inactive both at the baseline and follow-up,those keeping active over the period of follow-up had a substantial lower risk of incident CVD with the HR(95%CI)of 0.57(0.43–0.77).Conclusions The findings demonstrated that meeting and maintaining the recommended MVPA level could reduce the cardiovascular risk.Wider adoption of the PA recommendations would have considerable health impacts to the Chinese population. 展开更多
关键词 Cardiovascular disease China Cohort study Physical activity
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Subclinical atherosclerosis in northern and southern China: the Chinese paradox 被引量:7
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作者 Jie Huang Yang-Feng Wu +8 位作者 xiao-qing liu Ding Ding Lian-Cheng Zhao Bin Lu Xian Li Nathan D Wong Laurie D Dustin Stanley P Azen Robert C Detrano 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2011年第2期72-77,共6页
背景冠的心疾病(CHD ) 的发生是更高的在北比在南部的中国,然而,在传统的 CHD 的差别冒险的,解释这。没有学习在可以帮助在发生解释差别的无临床症状的动脉粥样硬化检验了差别。这研究为在北、南部的中国之间的石灰化用冠的计算断层... 背景冠的心疾病(CHD ) 的发生是更高的在北比在南部的中国,然而,在传统的 CHD 的差别冒险的,解释这。没有学习在可以帮助在发生解释差别的无临床症状的动脉粥样硬化检验了差别。这研究为在北、南部的中国之间的石灰化用冠的计算断层摄影术(CT ) 在无临床症状的动脉粥样硬化检验了这些差别。我们在一个大多中心选择了参加者的一件随机的样品的方法为冠的钙在一个北城市(诺思) 里扫描的进行中的流行病的学习(北京, n = 49 ) 并且在二个南部的城市(南方) 里(上海, n = 50,并且广州, n = 50 ) 。从三个领域中心的参加者(意味着年龄 67 年) 经历了用动脉粥样硬化扫描的多种族的学习为冠的钙测量扫描的冠的风险因素评估和心脏的 CT 协议。结果调整了在诺思中国(北京) 的转变木头的冠的动脉钙 20 是 3.1 +/-0.4 并且在华南(上海和广州) 是 2.2 +/- 0.3 (P = 0.04 ) 。为北京的北城市的吝啬的钙分数比广州的南部的城市的高三倍(P = 0.01 ) 并且比为上海的南部的城市高 2.5 倍(P = 0.03 ) 。结论无临床症状的动脉粥样硬化的程度在广州和上海的二个南部的城市里比那在北京的北城市里是显著地更高的,甚至在为标准心脏的风险因素调整以后。这发现建议标准风险因素充分不在临床的 CHD 发生解释北方南方差别。 展开更多
关键词 动脉粥样硬化 中国北部 临床 计算机断层扫描 北方城市 中国南方 冠状动脉 悖论
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Effects of the total physical activity and its changes on incidence, progression, and remission of hypertension 被引量:3
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作者 Can CAI Fang-Chao liu +17 位作者 Jian-Xin LI Ke-Yong HUANG Xue-Li YANG Ji-Chun CHEN xiao-qing liu Jie CAO Shu-Feng CHEN Chong SHEN Ling YU Fang-Hong LU Xian-Ping WU Lian-Cheng ZHAO Ying LI Dong-Sheng HU Jian-Feng HUANG Xiao-Yang ZHOU Xiang-Feng LU Dong-Feng GU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2021年第3期175-184,共10页
OBJECTIVES Moderate to vigorous physical activity is recommended to prevent hypertension according to the current guidelines.However,the degree to which the total physical activity(TPA)and its changes benefit normoten... OBJECTIVES Moderate to vigorous physical activity is recommended to prevent hypertension according to the current guidelines.However,the degree to which the total physical activity(TPA)and its changes benefit normotensives and hypertensives is uncertain.We aimed to examine the effects of TPA and its changes on the incidence,progression,and remission of hypertension in the large-scale prospective cohorts.METHODS A total of 73,077 participants(55,101 normotensives and 17,976 hypertensives)were eligible for TPA analyses.During a mean follow-up of 7.16 years(394,038 person-years),12,211 hypertension cases were identified.TPA was estimated as metabolic equivalents and categorized into quartiles.Cox proportional hazards regression and multivariable logistic regression were used to estimate associations of TPA and changes in TPA with incident hypertension and progression/remission of hypertension.RESULTS Compared with the lowest quartile of TPA,normotensives at the third and the highest quartile had a decreased risk of incident hypertension,with hazard ratios(HRs)of 0.86[95%confidence interval(CI):0.81−0.91]and 0.81(95%CI:0.77−0.86),respectively.Hypertensives at the highest quartile of TPA demonstrated a decreased risk of progression of hypertension[odds ratio(OR)=0.87,95%CI:0.79−0.95],and an increased probability of hypertension remission(OR=1.17,95%CI:1.05−1.29).Moreover,getting active from a sedentary lifestyle during the follow-up period could reduce 25%(HR=0.75,95%CI:0.58−0.96)risk of incident hypertension,whereas those becoming sedentary did not achieve benefit from initially being active.CONCLUSIONS Our findings indicated that increasing and maintaining TPA levels could benefit normotensives,whereas higher TPA levels were needed to effectively control progression and improve remission of hypertension.Physical activity played undoubtedly an essential role in both primary and secondary prevention of hypertension. 展开更多
关键词 HYPERTENSION REMISSION PREVENTION
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Positive Rate of Different Hepatitis B Virus Serological Markers in Peking Union Medical College Hospital,a General Tertiary Hospital in Beijing 被引量:1
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作者 Yue-qiu Zhang Sai-nan Bian +7 位作者 xiao-qing liu Shao-xia Xu Li-fan Zhang Bao-tong Zhou Wei-hong Zhang Yao Zhang Ying-chun Xu Guo-hua Deng 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第1期17-22,共6页
Objectives To investigate the positive rate of different hepatitis B virus(HBV) serological markers,and the demographic factors related to HBV infection.Methods We enrolled all patients tested for HBV serological mark... Objectives To investigate the positive rate of different hepatitis B virus(HBV) serological markers,and the demographic factors related to HBV infection.Methods We enrolled all patients tested for HBV serological markers,such as HBV surface antigen(HBsAg),HBV surface antibody(HBsAb),hepatitis B e antigen(HBeAg),hepatitis B e antibody(HBeAb),HBV core antibody(HBcAb),and HBV-DNA from July 2008 to July 2009 in Peking Union Medical College Hospital.The positive rate of each HBV serological marker was calculated according to gender,age,and department,respectively.The positive rates of HBV-DNA among patients with positive HBsAg were also analyzed.Results Among 27 409 samples included,2681(9.8%) were HBsAg positive.When patients were divided into 9 age groups,the age-specific positive rate of HBsAg was 1.2%,9.6%,12.3%,10.9%,10.3%,9.7%,8.0%,S.8%,and 4.3%,respectively.The positive rate of HBsAg in non-surgical department,surgical department,and health examination center was 16.2%,5.8%> and 4.7%,respectively.The positive rate of HBsAg of males(13.3%) was higher than that of females(7.3%,P=0.000).Among the 2681 HBsAg(+)patients,1230(45.9%) had HBV-DNA test,of whom 564(45.9%) were positive.Patients with HBsAg(+),HBeAg(+),and HBcAg(+) result usually had high positive rate of HBV-DNA results(71.8%,P=0.000).Conclusions Among this group of patients in our hospital,the positive rate of HBsAg was relatively high.Age group of 20-29,males,and patients in non-surgical departments were factors associated with high positive rate of HBsAg. 展开更多
关键词 乙型肝炎病毒表面抗原 综合性医院 阳性率 标志物 血清学 北京市 HBV-DNA HBsAg
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Analysis of electro-optical intensity modulator for bunch arrival-time monitor at SXFEL
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作者 Jin-Guo Wang xiao-qing liu +3 位作者 Lie Feng Wen-Yan Zhang Xing-Tao Wang Bo liu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第1期1-9,共9页
A bunch arrival-time monitor(BAM) based on an electro-optical intensity modulation scheme is currently under development at Shanghai Soft X-ray Free-Electron Laser to meet the high-resolution requirements for bunch st... A bunch arrival-time monitor(BAM) based on an electro-optical intensity modulation scheme is currently under development at Shanghai Soft X-ray Free-Electron Laser to meet the high-resolution requirements for bunch stability. The BAM uses a radio frequency signal generated by a pickup cavity to modulate the reference laser pulses in an electro-optical intensity modulator(EOM), and the bunch arrival-time information is derived from the amplitude change of the laser pulse after laser pulse modulation.EOM is a key optical component in the BAM system.Through the basic principle analysis of BAM, many parameters of the EOM are observed to affect the measurement resolution of the BAM system. Therefore, a systematic analysis of the EOM is crucial. In this paper, we present two schemes to compare and analyze an EOM and provide a reference for selecting a new version of the EOM. 展开更多
关键词 BUNCH arrival-time MONITOR (BAM) Soft X-ray Free-Electron Laser (SXFEL) High resolution ELECTRO-OPTICAL intensity modulator (EOM)
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2.856 GHz microwave signal extraction from mode-locked Erfiber lasers with sub-100 femtosecond timing jitter
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作者 Wen-Yan Zhang xiao-qing liu +3 位作者 Lie Feng Tai-He Lan Xing-Tao Wang Bo liu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第6期141-146,共6页
A balanced optical microwave phase detector(BOMPD) based on a 3 × 3 coupler is presented. This system was developed to extract ultra-low-jitter microwave signals from optical pulse trains emitted by mode-locked E... A balanced optical microwave phase detector(BOMPD) based on a 3 × 3 coupler is presented. This system was developed to extract ultra-low-jitter microwave signals from optical pulse trains emitted by mode-locked Er-fiber lasers, and synchronized microwave and laser systems. We demonstrate that the BOMPD achieves a precision of synchronization of less than 100 femtosecond of timing jitter. The experimental setup can be applied to the soft X-ray free-electron laser located on the campus of the Shanghai synchrotron radiation facility. A microwave signal with a 2.856 GHz frequency is extracted from a238 MHz mode-locked Er-laser, with an absolute timing jitter of 34 fs in the 10 Hz–10 MHz frequency offset range.In addition, the microwave and 238 MHz optical pulse signals are synchronized with a relative timing jitter of16 fs at the same frequency offset range. 展开更多
关键词 微波信号 激光系统 神经质 GHZ 预定 锁模 信号抽取 同步加速器
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Investigation of Hepatitis C Virus Infection Rate of Patients in a General Hospital
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作者 Yue-qiu Zhang Shao-xia Xu +5 位作者 Sai-nan Bian Li-fan Zhang Yao Zhang Wei-hong Zhang Ying-chun Xu xiao-qing liu 《国际感染病学(电子版)》 CAS 2013年第4期149-152,共4页
Objective To investigate the infection rate of hepatitis C virus among the ambulatory patients and in-patients of a tertiary teaching hospital,and study the demographic factors related to the prevalence of hepatitis C... Objective To investigate the infection rate of hepatitis C virus among the ambulatory patients and in-patients of a tertiary teaching hospital,and study the demographic factors related to the prevalence of hepatitis C virus infection.Methods All patients tested for hepatitis C virus antibody from July 2008 to July 2009 in Peking Union Medical College Hospital were enrolled in this cross-sectional analysis.The prevalence of hepatitis C virus infection was compared according to age,gender,and departments,respectively.Among patients with positive serology hepatitis C virus marker,the positivity of hepatitis C virus RNA was analysed.Results Among 29 896 subjects included,the hepatitis C virus antibody of 494 patients were positive(1.7%).When patients were divided into 9 age groups,the age specific prevalence of hepatitis C virus antibody were0.2%,1.7%,1.2%,1.1%,1.5%,1.9%,2.6%,2.4%and 2%,respectively.The prevalence of hepatitis C virus antibody in non-surgical department and surgical department was 3%and 1%,respectively.The prevalence of hepatitis C virus antibody of males was higher than that of the females.Total of 194 patients with positive hepatitis C virus antibody were tested for hepatitis C virus RNA,the RNA level of 113 patients(58.2%)were higher than the low detection limit.Conclusions The prevalence of hepatitis C virus antibody was relatively high among patients of general tertiary hospital.Age group of 60-69,males and patients in non-surgical departments were factors associated with high rate of hepatitis C virus infection. 展开更多
关键词 Infection rate Hepatitis C virus Patients of tertiary teaching hospital
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The Role of Renewable Protocatechol Acid in Epoxy Coating Modification: Significantly Improved Antibacterial and Adhesive Properties
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作者 Ming-Xuan Chen Jin-Yue Dai +5 位作者 Li-Yue Zhang Shuai-Peng Wang Jing-Kai liu Yong-Gang Wu Xin-Wu Ba xiao-qing liu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第1期63-72,I0008,共11页
It is of great significance to design epoxy coatings with superior antibacterial properties and high adhesive properties, as well as excellent processing, superior durability, and high transparency. However, it is sti... It is of great significance to design epoxy coatings with superior antibacterial properties and high adhesive properties, as well as excellent processing, superior durability, and high transparency. However, it is still a challenge because of the common complex design and synthesis. Herein, the bio-based monomer protocatechuic acid(PCA) was used as raw material, the catechol structure with high bonding and antibacterial properties was introduced into the flexible alkane segment of ethylene glycol diglycidyl ether(EGDE) through an efficient, and green method, and it was cured with isophorone diamine(IPDA) to prepare corresponding thermosets. The cured resins exhibited excellent allaround qualities, particularly in bonding and antibacterial. When 30% PCA was added to pure epoxy resin, the adhesion between substrate and coating increased from 4.40 MPa to 13.60 MPa and the antibacterial rate of coating against E. coli and S. aureus could approach 100%. All of this is due to the fact that the catechol structure present in PCA has the ability to interact with various substrates and alter the permeability of bacterial cell membranes. The architecture of this method offers a fresh approach to dealing with the issues of challenging raw material selection and complex synthesis techniques. 展开更多
关键词 Epoxy coatings THERMOSETS Catechol structure ANTIBACTERIAL High adhesion
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基于“多链超分子柱”的侧链液晶高分子柱状相 被引量:2
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作者 赵瑞颖 蒋旭强 +4 位作者 郑军峰 刘小青 徐艳双 杨爽 陈尔强 《高分子学报》 SCIE CAS CSCD 北大核心 2018年第8期973-986,共14页
一些具有伸展构象的侧链液晶高分子,如甲壳型液晶高分子或树枝化高分子,可以经由分子链的平行排列而呈现柱状液晶相.一般认为,该类柱状相的基本结构单元是单根高分子链所形成的超分子柱.而以几根链组装形成的超分子柱,即"多链超分... 一些具有伸展构象的侧链液晶高分子,如甲壳型液晶高分子或树枝化高分子,可以经由分子链的平行排列而呈现柱状液晶相.一般认为,该类柱状相的基本结构单元是单根高分子链所形成的超分子柱.而以几根链组装形成的超分子柱,即"多链超分子柱",也可作为侧链液晶高分子柱状相的基本结构单元,但多年以来这一现象并未引起人们的重视.近期,我们以hemiphasmid型侧链液晶高分子为研究对象,阐明了"多链超分子柱"是侧链液晶高分子柱状相微相分离的一种重要形式.本文从hemiphasmid型侧链液晶高分子的柱状相结构分析、化学结构对"多链超分子柱"的影响、"多链超分子柱"模型的理论分析与预测、"多链超分子柱"的"柱内缠结"以及hemiphasmid型侧链液晶聚降冰片烯的功能性等若干方面,对基于"多链超分子柱"的侧链液晶高分子柱状相进行了介绍.我们认为,深入研究"多链超分子柱"性质,将拓展侧链液晶高分子的应用领域,加深对高分子物理基本问题的认识. 展开更多
关键词 侧链液晶聚合物 Hemiphasmid型液晶基元 多链超分子柱 柱内缠结 形状记忆
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Growth rate,catalase and superoxide dismutase activities in rock carp(Procypris rabaudi Tchang) exposed to supersaturated total dissolved gas 被引量:12
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作者 xiao-qing liu Ke-feng LI +2 位作者 Jun DU Jia LI Ran LI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第11期909-914,共6页
Total dissolved gas supersaturation(TDGS) appears when the pressures of gases in a solution exceed the barometric pressures.TDGS is often caused by flood discharge at dams.It may lead to gas bubble disease(GBD) for fi... Total dissolved gas supersaturation(TDGS) appears when the pressures of gases in a solution exceed the barometric pressures.TDGS is often caused by flood discharge at dams.It may lead to gas bubble disease(GBD) for fish and biochemical responses of selected fish and other aquatic organisms.The purpose of this study was to determine the impact of long-term TDGS levels on the growth and biochemical responses of rock carp(Procypris rabaudi Tchang) dwelling in the upper reaches of the Yangtze River.Three-year-old rock carp were exposed to TDGS levels at 100%,104%,108%,112%,and 116% for 42 d.Samples were taken every 7 d after the start of the trial in order to determine catalase(CAT) and superoxide dismutase(SOD) activities in gill and muscle tissues.Samples were taken at Days 0 and 42 of exposure to determine growth rate.Little effect was found on growth rate in all treatment groups.SOD and CAT activities varied in different tissues,according to time of exposure and TDGS levels.The biochemical response of fish exposed to TDGS was more obvious in gill tissue than in muscle tissue.Surveys of SOD and CAT activities in different tissues offer important information about the effect of TDGS on the rare fish in the Yangtze River,and may help evaluate the risk to the aquatic eco-environment and aquatic ecosystem in the downstream of the Yangtze River. 展开更多
关键词 全部的溶解煤气的过度饱和(TDGS ) 岩石鲤鱼(Procypris rabaudi Tchang ) 生长率 过氧化氢酶 Superoxide dismutase
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Effects of total dissolved gas supersaturated water on lethality and catalase activity of Chinese sucker(Myxocyprinus asiaticus Bleeker) 被引量:11
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作者 Shi-chao CHEN xiao-qing liu +4 位作者 Wen JIANG Ke-feng LI Jun DU Dan-zhou SHEN Quan GONG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2012年第10期791-796,共6页
Total dissolved gas(TDG) supersaturation caused by dam sluicing can result in gas bubble trauma(GBT) in fish and threaten their survival.In the present study,Chinese suckers(Myxocyprinus asiaticus Bleeker) were expose... Total dissolved gas(TDG) supersaturation caused by dam sluicing can result in gas bubble trauma(GBT) in fish and threaten their survival.In the present study,Chinese suckers(Myxocyprinus asiaticus Bleeker) were exposed to TDG supersaturated water at levels ranging from 120% to 145% for 48 h.The median lethal concentration(LC 50) and the median lethal time(LT 50) were determined to evaluate acute lethal effects on Chinese suckers.The results showed that the LC 50 values of 4,6,8,and 10 h were 142%,137%,135%,and 130%,respectively.The LT 50 values were 3.2,4.7,7.8,9.2,and 43.4 h,respectively,when TDG supersaturated levels were 145%,140%,135%,130%,and 125%.Furthermore,the biological responses in Chinese suckers were studied by assaying the catalase(CAT) activities in gills and muscles at the supersaturation level of 140% within LT 50.The CAT activities in the gills and muscle tissues exhibited a regularity of a decrease after an increase.CAT activities in the muscles were increased significantly at 3/5LT 50(P<0.05) and then came back to the normal level.However,there were no significant differences between the treatment group(TDG level of 140%) and the control group(TDG level of 100%) on CAT activities in the gills before 3/5LT 50(P>0.05),but the activities were significantly lower than the normal level at 4/5LT 50 and LT 50(P<0.05). 展开更多
关键词 Total dissolved gas supersaturation Median lethal time(LT 50) Median lethal concentration(LC 50) Chinese sucker CATALASE
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Clinical and Laboratory Diagnosis of Intestinal Tuberculosis 被引量:13
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作者 Xiao-Chun Shi Li-Fan Zhang +2 位作者 Yue-Qiu Zhang xiao-qing liu Gui-Jun Fei 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第11期1330-1333,共4页
Background: Tuberculosis (TB) remains a worldwide problem. Intestinal TB (ITB) constitutes a major public health problem in developing countries and has been associated with significant morbidity and mortality. T... Background: Tuberculosis (TB) remains a worldwide problem. Intestinal TB (ITB) constitutes a major public health problem in developing countries and has been associated with significant morbidity and mortality. The aim of this study was to characterize the clinical, radiological, endoscopic, and pathological features of ITB and to define the strategy for establishing the diagnosis. Methods: A retrospective study (from January 2000 to June 2015) was carried out in Peking Union Medical College Hospital and all hospitalized cases were diagnosed as ITB during the study period were included. The relevant clinical information, laboratory results, microbiological, and radiological investigations were recorded. Results: Of the 85 cases, 61 cases (71.8%) were ranged from 20 to 50 years. The ileocecal region was involved in about 83.5% (71/85) of patients. About 41.2% (35/85) of patients had co-existing extra ITB, especially active pulmonary TB. Abdominal pain (82.4%) was the most common presenting symptom followed by weight loss (72.9%) and fever (64.7%). Both T-cell spot of TB test (T-SPOT.TB) and purified protein derivatives (PPD) tests were performed in 26 patients: 20 (76.9%) positive T-SPOT.TB and 13 (50.0%) positive PPD were detected, with a statistical significant difference (P- 0.046). Twenty cases (23.5%) were histopathology and/or pathogen confirmed TB; 27 cases (31.8%) were diagnosed by clinical manifestation consistent with ITB and evidence of active extra ITB; 38 cases (44.7%) were diagnosed by good response to diagnostic anti-TB therapy. Conclusions: ITB is difficult to diagnose even with modem medical techniques due to its nonspecific clinical and laboratory features. At present, combination of clinical, endoscopic, radiological, and pathological features continues to be the key to the diagnosis of ITB. 展开更多
关键词 DIAGNOSIS Intestinal Tuberculosis Extra-intestinal Tuberculosis
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From Furan to High Quality Bio-based Poly(ethylene furandicarboxylate) 被引量:10
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作者 Jing-Gang Wang xiao-qing liu Jin Zhu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第6期720-727,共8页
2,5-Furandicarboxylic acid(2,5-FDCA) has been regarded as the ideal bio-based alternative to terephthalic acid(TPA). In recent years, great efforts have been made to synthesize 2,5-FDCA through the following meth... 2,5-Furandicarboxylic acid(2,5-FDCA) has been regarded as the ideal bio-based alternative to terephthalic acid(TPA). In recent years, great efforts have been made to synthesize 2,5-FDCA through the following methods:(1) oxidation of 5-hydroxymethylfurfural(HMF) in the presence of complex biocatalyst or metallic catalyst;(2) conversion of 2-furoic acid via the well-known Henkel Reaction. Herein, a new strategy for the synthesis of 2,5-FDCA from furan and acetic anhydride under mild condition is reported. The purity of the resulted 2,5-FDCA was above 99.9%. Acetic acid and iodoform generated in the reaction were recyclable and no other harmful by-products were detected. The thus-obtained 2,5-FDCA was applied for the preparation of poly(ethylene furandicarboxylate)(PEF) of high quality in terms of high molecular weight and good appearance. 展开更多
关键词 2 5-Furandicarboxylic acid(2 5-FDCA) 2 5-Diacetylfuran(2 5-DAF) Iodoform reaction Furan Poly(ethylene furandicarboxylate)
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Improved myocardial perfusion and cardiac function by controlled-release basic fibroblast growth factor using fibrin glue in a canine infarct model 被引量:7
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作者 Shao-ping NIE Xiao WANG +6 位作者 Shi-bin QIAO Qiu-tang ZENG Ju-quan JIANG xiao-qing liu Xiang-ming ZHU Guo-xiang CAO Chang-sheng MA 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2010年第12期895-904,共10页
Objective: Angiogenic therapy is emerging as a potential strategy for the treatment of ischemic heart disease but is limited by a relatively short half-life of growth factors.Fibrin glue (FG) provides a reservoir for ... Objective: Angiogenic therapy is emerging as a potential strategy for the treatment of ischemic heart disease but is limited by a relatively short half-life of growth factors.Fibrin glue (FG) provides a reservoir for controlledrelease of growth factors.The aim of this study was to evaluate the effects of basic fibroblast growth factor (bFGF) incorporating FG on angiogenesis and cardiac performance in a canine infarct model.Methods: Acute myocardial infarction was induced by ligation of the left anterior descending coronary artery (LAD).Group I (n=6) underwent ligation of LAD alone.In Group II,transmural channels were created in the infarct area (n=6).In Group III,nontransmural channels were created to locate FG cylinders containing bFGF (n=6).Eight weeks after operation,myocardial perfusion was assessed by single photon emission computed tomography,cardiac function by echocardiography,and vascular development by immunohistochemical staining.Results: Total vascular density and the number of large vessels (internal diameter ≥50 μm) were dramatically higher in Group III than in Groups I and II at eight weeks.Only the controlled-release group exhibited an improvement in regional myocardial perfusion associated with lower defect score.Animals in Group III presented improved cardiac regional systolic and diastolic functions as well as global systolic function in comparison with the other two groups.Conclusions: Enhanced and sustained angiogenic response can be achieved by controlled-release bFGF incorporating FG within transmyocardial laser channels,thus enabling improvement in myocardial perfusion and cardiac function. 展开更多
关键词 Angiogenesis 基本成纤维细胞生长因素 控制版本 Ischemic 心疾病
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