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Study on Chaotic Characteristics of the Friction Process between High Hardness Alloy Steel and Cemented Carbide under C60 Nanoparticle Fluid Lubrication
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作者 Jingshan Huang Bin Yao +1 位作者 Qixin Lan Zhirong Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期525-550,共26页
Friction and wear phenomenon is a complex nonlinear system,and it is also a significant problem in the process of metal cutting.In order to systematically analyze the friction and wear process of tool material-workpie... Friction and wear phenomenon is a complex nonlinear system,and it is also a significant problem in the process of metal cutting.In order to systematically analyze the friction and wear process of tool material-workpiece material friction pair in the cutting process of high hardness alloy steel under different lubrication conditions,the chaotic characteristics of friction process between high hardness alloy steel and cemented carbide under the lubrication C60 nano-particles fluid are studied based on the chaos theory.Firstly,the friction and wear experiments of the friction pair between high hardness alloy steel and cemented carbide tool are carried out based on the ring-block friction and wear tester,and the results of friction force signal in time domain and wear width are obtained.Then,the friction signals in time domain are processed and transformed based on phase space reconstruction and recurrence plot theory,and the recurrence plots of different experimental groups under different lubrication conditions are generated.The evolution law of recurrence plot is further observed and studied,and the recursive quantitative index is analyzed.Finally,the cutting experiments of tool wear are carried out.The results show that the proposed method can intuitively and accurately reveal the wear evolution process and the wear feature identification law of the tool material-high hardness alloy steel pair under different lubrication conditions.Meanwhile,it is found that when the concentration of C60 nanoparticles is 200∼300 ppm,the stability of the friction pair system is best.The proposed method can provide a strategy for wear prediction in cutting process,and provide a theoretical basis and technical support for antifriction lubrication methods in practical cutting applications. 展开更多
关键词 c60 nanoparticles recurrence plot FRIcTION STABILITY
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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings
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作者 Zhijuan Zhao Lina Wang +7 位作者 Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期90-102,共13页
To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,lig... To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings. 展开更多
关键词 Pinus yunnanensis seedlings DROUGHT Non-structural carbohydrates c N P stoichiometric characteristics
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Correlations and stoichiometric characteristics of C,N,and P contents in Juniperus saltuaria plants,litter,and soil in the Sygera Mountains,southeastern Xizang,China
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作者 GUO Liangna LI Jiangrong +6 位作者 FU Fangwei ZHANG Bo ZHU Sijie LIU Yuzhuo LI Jieting CHEN Ganggang ZHANG Yibo 《Journal of Mountain Science》 SCIE CSCD 2024年第12期4254-4268,共15页
Research on the multicomponent synergistic relationships between plants,litter,and soil from the perspective of ecological stoichiometry helps to understand nutrient cycling and distribution mechanisms within ecosyste... Research on the multicomponent synergistic relationships between plants,litter,and soil from the perspective of ecological stoichiometry helps to understand nutrient cycling and distribution mechanisms within ecosystems.This study focused on Juniperus saltuaria,the dominant tree species in the forestline ecotone of Sygera Mountains,southeastern Xizang,China.We systematically measured and analyzed the Carbon(C),nitrogen(N),and phosphorus(P)contents and their relationships in plants(leaves,branches,trunks,fine roots),litter(undecomposed layer,partially decomposed layer,fully decomposed layer),and soil(0-10 cm,10-20 cm,20-40 cm)at different slope positions.The results showed significant differences in the C,N,and P contents and stoichiometry of plants and soil at different slope positions,while no significant differences were observed among litter layers.At the same slope position,the C,N,and P contents in leaves and surface soil were the highest,with soil nutrients significantly decreasing with increasing depth.For litter,the C content in the undecomposed layer was significantly higher than that in the partially and fully decomposed layers while the P content showed the opposite trend.Surface soil(0-20 cm)exhibited a decoupled relationship with plants but a coupled relationship with litter while deep soil(20-40 cm)showed a coupled relationship with plants.J.saltuaria showed faster growth rates on uphill slope.In this study area,J.saltuaria exhibited consistent trends of N,P,and N:P ratios homeostasis across different slope positions and organs,with leaves and fine roots both limited by N.Significant interactive effects between plants,litter,and soil nutrients were observed across different slope positions.Positive correlations were found between leaf and litter,and between fine root and leaf while the relationships between litter and soil,and between soil and fine root,varied.This study helps improve our understanding of the nutrient interactions between plants,litter,and soil in dominant species of alpine forest ecosystems,as well as their ecological adaptation mechanisms. 展开更多
关键词 Leaf-litter-soil system Slope position c:N:P stoichiometry Forestline ecotone Nutritional restriction Juniperus saltuaria
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Evolution of heart transplant donor characteristics in the 21st century: A United States single center’s experience
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作者 Alexander M Spring Christiana Gjelaj +10 位作者 Shivank Madan Snehal R Patel Omar Saeed Sandhya Murthy Yogita Rochlani Daniel B Sims Sasha Vukelic Stephen J Forest Jamil F Borgi Daniel J Goldstein Ulrich P Jorde 《World Journal of Transplantation》 2024年第3期22-29,共8页
Despite a record setting number of heart transplants performed annually,the national donor shortage continues to plague transplant teams across the United States.Here we describe the barriers to adaptation of numerous... Despite a record setting number of heart transplants performed annually,the national donor shortage continues to plague transplant teams across the United States.Here we describe the barriers to adaptation of numerous“non-traditional”orthotopic heart transplant donor characteristics including donors with hepatitis C virus,those meeting criteria for donation after cardiac death,donors with coronavirus disease 19 infection,donors with the human immunodeficiency virus,and grafts with left ventricular systolic dysfunction.Our center’s objective was to increase our transplant volume by expanding our donor pool from“traditional”donors to these“non-traditional”donors.We detail how medical advances such as certain laboratory studies,pharmacologic interventions,and organ care systems have allowed our center to expand the donor pool thereby increasing transplantation volume without adverse effects on outcomes. 展开更多
关键词 Orthotopic heart transplantation Hepatitis c virus cOVID-19 Left ventricular systolic dysfunction Human immunodeficiency virus Donation after cardiac death
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Interspecific Transition Among Caragana microphylla, C. davazamcii and C. korshinskii Along Geographic Gradient. Ⅱ. Characteristics of Photosynthesis and Water Metabolism 被引量:13
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作者 马成仓 高玉葆 +1 位作者 郭宏宇 王金龙 《Acta Botanica Sinica》 CSCD 2003年第10期1228-1237,共10页
The characteristics of photosynthesis and water metabolism of Caragana microphylla Lam.,C. davazamcii Sancz. and C. korshinskii Kom. populations in different sites (117.6o-105.7o E, 44.6o-38.8o N)were studied. (1) Fro... The characteristics of photosynthesis and water metabolism of Caragana microphylla Lam.,C. davazamcii Sancz. and C. korshinskii Kom. populations in different sites (117.6o-105.7o E, 44.6o-38.8o N)were studied. (1) From the east to the west, the responses of the three species to photosyntheticallyavailable radiation (PAR) in net photosynthesis rate increased, the relative humidity of the air whichcorresponded to the occurrence of maximum photosynthesis rate decreased, and the corresponding airtemperature increased. Along the same gradient, the before-noon superiority of the photosynthesis be-came evident, and the photosynthesis rate and the light use efficiency (LUE ) increased, while the transp-iration rate decreased, thus the water use efficiency (WUE ) increased notably, and the leaf water contentdecreased gradually. From the east to the west, the plants took a water-saving strategy step by step withhigher photosynthesis rate and lower transpiration rate. These physiological changes in the plants wereadaptable to the conditions of light, temperature and humidity in the habitat of the plants, and might be thebiological foundation for the geographical transition among C. microphylla , C. davazamcii and C. korshinskii.(2) The adaptation of photosynthetic system of C. microphylla , C. davazamcii and C. korshinskii to PAR, airhumidity and temperature exhibited the interspecific continuity, which was consistent with theenvironmental gradient. In different species and different sites, the diurnal changes of net photosynthesisrate, the daily cumulative value of net photosynthesis, the diurnal changes of transpiration rate, the dailycumulative value of transpiration, the water use efficiency and the diurnal changes of leaf water contentvaried with longitudinal descent (from the east to the west). The characteristics of photosynthesis andwater metabolism indicated that the geographical transition among C. microphylla , C. davazamcii and C.korshinskii was in gradual change, and these three species formed a geographical cline. 展开更多
关键词 caragana microphylla c. davazamcii c. korshinskii geographical transition PHOTOSYNTHESIS water metabolism
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Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Seeds under Different Light Intensities 被引量:2
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作者 孙兆伟 刘金花 +1 位作者 李佳 张永清 《Agricultural Science & Technology》 CAS 2013年第6期842-846,共5页
[Objective] This study aimed to investigate the primary and secondary metabolisms during the germination of Scutellaria baicalensis Georgi seeds under different light intensities. [Method] The activities of CHL, solub... [Objective] This study aimed to investigate the primary and secondary metabolisms during the germination of Scutellaria baicalensis Georgi seeds under different light intensities. [Method] The activities of CHL, soluble sugar, PAL, C4H and CHS were determined with ultraviolet spectrophotometry. The secondary metabolites were detected by High Performance Liquid Chromatography (HPLC). [Result] The results indicate that the germination of Scutellaria baicalensis Georgi seeds is not sensitive to light and the seedlings were very sensitive to light. The CHL, soluble sugar, PAL, C4H and CHS continuously increased with light intensity. The content of secondary metabolites also increased. [Conclusion] Light increased the formation of leaf photosynthetic pigment, thereby affecting the primary metabolites. The activities of PAL, C4H and CHS significantly increased with the development of light intensity. Finally the secondary metabolites of medicinal plants increased sharply. Therefore, the quality of Scutellaria baicalensis Georgi materials can be improved by increasing the light intensity moderately. 展开更多
关键词 Light intensity PAL c4H cHS Secondary metabolites
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Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Seeds under Different Temperatures 被引量:2
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作者 刘金花 李佳 张永清 《Agricultural Science & Technology》 CAS 2010年第9期213-216,共4页
[Objective] To study the germination characteristics and secondary metabolism of Scutellaria baicalensis Georgi seeds under different temperatures.[Method]The activities of superoxide dismutase(SOD)and peroxidase(... [Objective] To study the germination characteristics and secondary metabolism of Scutellaria baicalensis Georgi seeds under different temperatures.[Method]The activities of superoxide dismutase(SOD)and peroxidase(POD)were determined with lactoflavine-NBT method and guaiacol-colorimetry assay,respectively.The catalase(CAT),ascorbate peroxidase(APX),phenylalanine ammonia-lyase(PAL)and cinnamic acid 4-Hydroxylase(C4H)were determined with ultraviolet spectrophotometry.The secondary metabolites were detected by High Performance Liquid Chromatography(HPLC).[Result]The germination percentage,germination potentiality and germination index were seriously affected by low or high temperature.The proper germination temperature was 20-25 ℃.The activities of SOD,POD and CAT were significantly decreased as comparison to suitable temperature.The activities of PAL and C4H were also significantly decreased as comparision to suitable temperature which was accordance to the secondary metabolites.There was a positive correlation between the flavonoids content and the PAL and C4H activity(r=0.956,r=0.951,P0.05).[Conclusion]The quality of the skullcaps could be improved by improving the activity of PAL and C4H.The proper temperature for the seed germination and the formation of secondary metabolites was 20 ℃. 展开更多
关键词 Germination characteristics Antioxidant enzyme PAL c4H Secondary metabolites
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C反应蛋白/白蛋白比值对2型糖尿病合并急性心肌梗死患者远期不良心脑血管事件的预测价值研究
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作者 马娟 马盛宗 +2 位作者 燕茹 马学平 贾绍斌 《中国全科医学》 CAS 北大核心 2025年第6期705-712,共8页
背景急性心肌梗死(AMI)是威胁全球公众健康的主要原因之一。虽然已有相应的再灌注治疗策略,但AMI相关的主要不良心脑血管事件(MACCEs)仍然是全世界人口死亡的原因之一。尤其合并糖尿病的AMI患者,因冠状动脉病变复杂,病变程度严重,尽早... 背景急性心肌梗死(AMI)是威胁全球公众健康的主要原因之一。虽然已有相应的再灌注治疗策略,但AMI相关的主要不良心脑血管事件(MACCEs)仍然是全世界人口死亡的原因之一。尤其合并糖尿病的AMI患者,因冠状动脉病变复杂,病变程度严重,尽早发现和判断该部分患者远期预后相对困难,因此寻找相对简便、易获得的实验室指标,有利于为2型糖尿病(T2DM)合并AMI患者经皮冠状动脉介入(PCI)术后MACCEs的预测提供依据。目的探讨血清C反应蛋白(CRP)/白蛋白(Alb)比值(CAR)对T2DM合并AMI患者PCI术后远期MACCEs的预测价值。方法纳入2014—2019年就诊于宁夏医科大学总医院心血管内科1683例T2DM合并AMI患者为研究对象,收集患者的一般临床资料与检查结果。对所有患者进行电话或门诊随访,以全因死亡、非致死性心肌梗死、再发不稳定型心绞痛、非致死性脑卒中、新发心力衰竭或心力衰竭加重再入院、再次血运重建作为MACCEs。根据患者随访期间是否发生MACCEs分为MACCEs组(508例)和非MACCEs组(1175例)。采用单因素及多因素Logistic回归分析探讨T2DM合并AMI患者MACCEs事件的影响因素。采用Kaplan-Meier法绘制患者的生存曲线,生存曲线的比较采用Log-rank检验。采用受试者工作特征(ROC)曲线分析CAR对T2DM合并AMI患者远期发生MACCEs的预测效能,使用净重分类改善指标(NRI)和综合判别指数(IDI)评价CAR对T2DM合并AMI患者预后评估的改善效果。结果1683例患者中508例(30.18%)患者发生MACCEs。多因素Logistic回归分析显示高血压病[OR(95%CI)=1.994(1.142~3.483)]、冠状动脉植入支架长度[OR(95%CI)=1.031(1.002~1.062)]、CRP[OR(95%CI)=0.950(0.915~0.986)]、Alb[OR(95%CI)=0.933(0.880~0.989)]及CAR[OR(95%CI)=5.582(1.705~18.277)]是T2DM合并AMI患者PCI术后发生MACCEs的影响因素(P<0.05)。根据CAR中位表达水平(0.86),将患者分为CAR<0.86组和CAR≥0.86组,Log-rank检验结果显示,CAR≥0.86组MACCEs发生率高于CAR<0.86组(52.68%与22.92%;χ^(2)=65.65,P<0.001)。ROC曲线显示CAR预测T2DM合并AMI患者发生MACCEs的ROC曲线下面积为0.728(95%CI=0.702~0.754),最佳截断值为0.576,灵敏度为0.617,特异度为0.747。在基线模型基础上,与CRP、Alb相比,CAR能明显改善对患者发生MACCEs的预测效果(NRI=0.377,IDI=0.166,C指数=0.690;P<0.05)。结论CAR是T2DM合并AMI患者PCI术后远期MACCEs发生风险的有效预测指标。 展开更多
关键词 心肌梗死 糖尿病 2型 主要不良心脑血管事件 c反应蛋白 白蛋白 预测
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Preparation and characteristic analysis of rice husk high boiling solvent lignin 被引量:2
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作者 陈云平 程贤甦 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第2期159-163,共5页
Rice husk high boiling solvent lignin (RHL) was prepared by high boiling solvent method, and its characteristics was analyzed by using chemical composition analysis, infrared spectroscopy, and ^1H-NMR and ^13C-NMR s... Rice husk high boiling solvent lignin (RHL) was prepared by high boiling solvent method, and its characteristics was analyzed by using chemical composition analysis, infrared spectroscopy, and ^1H-NMR and ^13C-NMR spectroscopy. The optimum prepared condition was that the rice husk with 70%-90% aqueous solution of 1, 4-butanediol was mixed with autoclave, under a certain weight ratio of solid raw material and solvent, heated to 200-220℃ for 1.0-3.0 h, then water-insoluble RHL was separated from the liquor reaction mixture by water precipitation. Results suggested that the lower digestion temperature and concentration of 1,4-butanediol were both unfavorable for extracting lignin. Chemical weight-average molecular weight of RHL was 1939 g·mol^-1, and the residual polysaccharide content was 5.12%. The ^1H-NMR spectra of RHL showed the relative intensity ratio, aliphatic over aromatic methoxyl groups, situated at 3.5-3.8 and 3.8-4.0 ppm, respectively. The results from ^13C-NMR spectra showed that β-O-4 bond and β-5 carbon-carbon linkage were the major linkages between RHL units. The C9-formula of RHL was calculated by the experiment data. 展开更多
关键词 high boiling solvent method rice husk lignin c9-formula
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血清可溶性CD40配体、腱糖蛋白C、甲壳质酶蛋白-40联合检测对维持性血液透析并发心血管事件的预测作用
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作者 吕宁 杨立娟 +2 位作者 尹林林 王丹 宴俊芳 《陕西医学杂志》 CAS 2025年第1期123-126,137,共5页
目的:探讨血清可溶性CD40配体(sCD40L)、腱糖蛋白C(TN-C)、甲壳质酶蛋白-40(YKL-40)联合检测对维持性血液透析(MHD)并发心血管事件的预测价值。方法:选择170例MHD患者为研究对象,依据不良心血管事件(MACE)发生情况分两组,即MACE组(n=63... 目的:探讨血清可溶性CD40配体(sCD40L)、腱糖蛋白C(TN-C)、甲壳质酶蛋白-40(YKL-40)联合检测对维持性血液透析(MHD)并发心血管事件的预测价值。方法:选择170例MHD患者为研究对象,依据不良心血管事件(MACE)发生情况分两组,即MACE组(n=63)和非MACE组(n=107),另选同期健康体检者为对照组(n=152)。比较各组血清sCD40L、TN-C、YKL-40水平,分析以上指标与MHD发生MACE的相关性及MHD并发MACE的危险因素,绘制受试者工作曲线(ROC)分析其预测价值。结果:MHD组血清sCD40L、TN-C、YKL-40水平高于对照组(均P<0.05)。MACE组的年龄、透析龄及血清sCD40L、TN-C、YKL-40水平高于非MACE组(均P<0.05)。MHD并发MACE与年龄、透析龄及血清sCD40L、TN-C、YKL-40水平呈正相关(均P<0.05)。多因素Logistic回归分析显示,MHD并发MACE的独立危险因素包括高水平sCD40L、TN-C、YKL-40以及高年龄和透析龄(均P<0.05)。血清sCD40L、TN-C、YKL-40单独及联合预测MHD并发MACE的AUC分别为0.701、0.679、0.754、0.875,联合预测价值最高,其次为YKL-40、sCD40L、TN-C(均P<0.05)。结论:MHD并发MACE患者血清sCD40L、TN-C、YKL-40水平有升高趋势,三者均为MACE发生独立危险因素,联合检测对MHD发生MACE有一定的预测价值。 展开更多
关键词 维持性血液透析 心血管事件 可溶性cD40配体 腱糖蛋白c 甲壳质酶蛋白-40 预测
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血清MC-CP、CCL26、DcR3水平在COPD并发OSAS诊断中的临床价值
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作者 陈丽萍 史永兴 +4 位作者 陈艳红 冯平 张长洪 林卫佳 项保利 《基础医学与临床》 CAS 2025年第1期76-80,共5页
目的探究血清肥大细胞羧肽酶(MC-CP)、趋化因子26(CCL26)、诱饵受体3(DcR3)水平在慢性阻塞性肺疾病(COPD)并发阻塞性睡眠呼吸暂停综合征(OSAS)诊断中的临床价值。方法选取2021年1月至2023年1月河北北方学院附属第一医院收治的COPD患者90... 目的探究血清肥大细胞羧肽酶(MC-CP)、趋化因子26(CCL26)、诱饵受体3(DcR3)水平在慢性阻塞性肺疾病(COPD)并发阻塞性睡眠呼吸暂停综合征(OSAS)诊断中的临床价值。方法选取2021年1月至2023年1月河北北方学院附属第一医院收治的COPD患者90例,其中单纯COPD患者48例即为COPD组,COPD合并OSAS患者42例即为COPD-OSAS组。同期选取在河北北方学院附属第一医院体检健康志愿者48例为对照组。采用酶联免疫吸附试验(ELISA)检测血清MC-CP、CCL26、DcR3水平。受试者工作特征(ROC)和曲线下面积(AUC)分析血清MC-CP、CCL26、DcR3水平在COPD并发OSAS诊断中的临床价值。多因素Logistic回归分析COPD并发OSAS的影响因素。结果与对照组相比,COPD组和COPD-OSAS组患者吸烟指数、C反应蛋白(CRP)、白细胞计数(WBC)水平依次显著升高,1秒钟用力呼气容积与用力肺活量的比(FEV1/FVC)依次显著降低(P<0.05);与对照组相比,COPD组和COPD-OSAS组患者MC-CP、CCL26、DcR3水平依次显著升高(P<0.05);血清MC-CP、CCL26、DcR33者联合对COPD并发OSAS诊断的AUC比单独诊断的更高(Z=4.066,P<0.001;Z=2.391,P<0.05;Z=2.353,P<0.05)。多因素Logistic回归分析显示,吸烟指数、MC-CP、CCL26、DcR3水平是COPD并发OSAS的影响因素(P<0.05)。结论COPD并发OSAS患者血清中MC-CP、CCL26、DcR3表达水平升高,三者联合可提高对COPD并发OSAS的诊断价值。 展开更多
关键词 肥大细胞羧肽酶 趋化因子26 诱饵受体3 慢性阻塞性肺疾病 阻塞性睡眠呼吸暂停综合征
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Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi under Different Illumination Time 被引量:4
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作者 刘金花 李佳 +1 位作者 崔淑兰 张永清 《Agricultural Science & Technology》 CAS 2014年第8期1312-1316,共5页
This study aimed to investigate the primary and secondary metabolism of Scutel aria baicalensis Georgi during seed germination process under different il umination time. [Method] Chlorophyl (CHL) content, soluble su... This study aimed to investigate the primary and secondary metabolism of Scutel aria baicalensis Georgi during seed germination process under different il umination time. [Method] Chlorophyl (CHL) content, soluble sugar content, phenylalanine ammonia lyase (PAL) activity and cinnamate-4-hydroxylase (C4H) ac-tivity were determined with ultraviolet spectrophotometry. The secondary metabolites were detected by high performance liquid chromatography (HPLC). [Result] The re-sults indicated that the germination of S. baicalensis seeds was not sensitive to light and the seedlings were very sensitive to light. CHL content, soluble sugar content, PAL activity and C4H activity increased continuously with the il umination time. The secondary metabolites showed a similar trend. [Conclusion] Il umination time promoted the formation of leaf photosynthetic pigments, thereby affecting the synthesis of primary and secondary metabolites and the activities of PAL and C4H. Therefore, the quality of S. baicalensis can be improved by regulating the il umina-tion time appropriately. 展开更多
关键词 Illumination time PAL c4H secondary metabolites
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Microstructure characteristic and formation mechanism of crackfree TaC coating on C/C composite 被引量:7
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作者 李国栋 熊翔 黄伯云 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第6期1206-1213,共8页
The microstructure characteristic and formation mechanism of the crackfree and ablation-resistant TaC coating deposited on the C/C composite by Chemical Vapour Deposition(CVD) were investigated, using the reaction s... The microstructure characteristic and formation mechanism of the crackfree and ablation-resistant TaC coating deposited on the C/C composite by Chemical Vapour Deposition(CVD) were investigated, using the reaction system of TaCl5-C3H6-H2-Ar. The results show that the nanosized pore structure formed in the TaC coating interior during CVD process is the main factor to reduce the hardness, elastic modulus, linear expansibility and inner thermal stress. Then crackfree coatings can be prepared and their thermal shock resistance can be enhanced. To obtain the dense and homogeneous matrix surface is necessary for the crackfree and low stress coating. The TaC coating structure that distributes from the dense matrix towards loose coating surface will result in the thick crackfree coating with good thermal shock resistance. 展开更多
关键词 c/c复合材料 TAc涂层 显微结构 成型机制 裂纹
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Clinical characteristics and current management of hepatitis B and C in China 被引量:8
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作者 Yong-Tao Sun Yue-Xin Zhang +7 位作者 Hong Tang Qing Mao Xiao-Zhong Wang Ling-Yi Zhang Hong Chen Ying-Na Zhong Shu-Mei Lin Da-Zhi Zhang 《World Journal of Gastroenterology》 SCIE CAS 2014年第37期13582-13590,共9页
AIM: To describe a population of outpatients in China infected by hepatitis B virus (HBV) and/or hepatitis C virus (HCV), and assess their current management status. METHODS: A multicenter, cross-sectional study of HB... AIM: To describe a population of outpatients in China infected by hepatitis B virus (HBV) and/or hepatitis C virus (HCV), and assess their current management status. METHODS: A multicenter, cross-sectional study of HBV- and/or HCV-infected patients was conducted from August to November, 2011 in western China. Patients >= 18 years of age with HBV and/or HCV infections who visited outpatient departments at 10 hospitals were evaluated, whether treated or not. Data were collected on the day of visit from medical records and patient interviews. RESULTS: A total 4010 outpatients were analyzed, including 2562 HBV- infected and 1406 HCV-infected and 42 HBV/HCV co-infected patients. The median duration of documented infection was 7.5 years in HBV- infected and 1.8 years in HCV-infected patients. Cirrhosis was the most frequent hepatic complication (12.2%), appearing in one-third of patients within 3 years prior to or at diagnosis. The HCV genotype was determined in only 10% of HCV-infected patients. Biopsy data were only available for 54 patients (1.3%). Antiviral medications had been received by 58.2% of patients with HBV infection and 66.6% with HCV infection. Nucleos(t) ide analogs were the major antiviral medications prescribed for HBV- infected patients (most commonly adefovir dipivoxil and lamivudine). Ribavirin + pegylated interferon was prescribed for two-thirds of HCV-infected patients. In the previous 12 mo, around one-fifth patients had been hospitalized due to HBV or HCV infection. CONCLUSION: This observational, real-life study has identified some gaps between clinical practice and guideline recommendations in China. To achieve better health outcomes, several improvements, such as disease monitoring and optimizing antiviral regimens, should be made to improve disease management. (C) 2014 Baishideng Publishing Group Inc. All rights reserved. 展开更多
关键词 Hepatitis B Hepatitis c clinical characteristics TREATMENT
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Individualization of chronic hepatitis C treatment according to the host characteristics 被引量:2
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作者 Nikolaos K Gatselis Kalliopi Zachou +2 位作者 Asterios Saitis Maria Samara George N Dalekos 《World Journal of Gastroenterology》 SCIE CAS 2014年第11期2839-2853,共15页
Hepatitis C virus(HCV)infection is a global health problem that affects more than 170 million people worldwide.It is a major cause of cirrhosis and hepatocellular carcinoma,making the virus the most common cause of li... Hepatitis C virus(HCV)infection is a global health problem that affects more than 170 million people worldwide.It is a major cause of cirrhosis and hepatocellular carcinoma,making the virus the most common cause of liver failure and transplantation.The standardof-care treatment for chronic hepatitis C(CHC)has been changed during the last decade and direct acting antiviral drugs have already been used.Besides,understanding of the pathogenesis of CHC has evolved rapidly during the last years and now several host factors are known to affect the natural history and response to treatment.Recent genome-wide association studies have shown the important role of interleukin-28B and inosine triphosphatase in HCV infection.The present review article attempts to summarize the current knowledge on the role of host factors towards individualization of HCV treatment. 展开更多
关键词 chronic hepatitis c Hepatitis c virus host factors Interleukin 28B Inosine triphosphatase Single nucleotide polymorphism
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Preparation and characteristics of C/C composite brake disc by multi-cylindrical chemical vapor deposition processes 被引量:3
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作者 袁毅东 张富宽 周万成 《Journal of Central South University of Technology》 EI 2005年第4期400-402,共3页
The C/C composite brake discs were prepared by tri-cylindrical chemical vapor deposition (CVD) process. The optimum processing parameters were as follows: deposition temperature was 830 - 930 ℃, the gas- flow rate... The C/C composite brake discs were prepared by tri-cylindrical chemical vapor deposition (CVD) process. The optimum processing parameters were as follows: deposition temperature was 830 - 930 ℃, the gas- flow rates of N2 and propylene were 4.8 - 5.2 m^3/h and 5.8 - 6.2 m^3/h, respectively, the furnace pressure was 4.5 - 5.5 kPa and the deposition time was 200 h. The effects of processing parameters on the densified rates, thermal-physical property and mechanical performance of C/C composite brake discs were studied. The results show that density, heat conductivity, bend strength and abrasion ratio of the multi-cylindrica brake discs are 1. 02 - 1. 78 g/cm^3 , 31 W/(m·K), 114 MPa and 7μm/s, respectively, which are approximately similar to those of the singlecylindrical ones. The gas tlow rate has no relation to the number of the cylinder and furnace loading. The utilization ratio of carbon can be improved by multi-cylinder CVD process without changing the characteristics of brake disc. 展开更多
关键词 c/c composite brake disc chemical vapor deposition multi-cylindrical mechanical property
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Tribological characteristics of C/C-SiC braking composites under dry and wet conditions 被引量:3
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作者 李专 肖鹏 +1 位作者 熊翔 朱苏华 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第5期1071-1075,共5页
C/C-SiC braking composites,based on reinforcement of carbon fibers and matrices of carbon and silicon carbide,were fabricated by warm compaction and in situ reaction process.The tribological characteristics of C/C-SiC... C/C-SiC braking composites,based on reinforcement of carbon fibers and matrices of carbon and silicon carbide,were fabricated by warm compaction and in situ reaction process.The tribological characteristics of C/C-SiC braking composites under dry and wet conditions were investigated by means of MM-1000 type of friction testing machine.The influence of dry and wet conditions on the tribological characteristics of the C/C-SiC composites was ascertained.Under dry condition,C/C-SiC braking composites show superior tribological characteristics,including high coefficient of friction (0.38),good abrasive resistance (thickness loss is 1.10 μm per cycle) and steady breaking.The main wear mechanism is plastic deformation and abrasion caused by plough.Under wet condition,frictional films form on the worn surface.The coefficient of friction (0.35) could maintain mostly,and the thickness loss (0.70 μm per cycle) reduces to a certain extent.Furthermore,braking curves are steady and adhesion and oxidation are the main wear mechanisms. 展开更多
关键词 c/c-SIc 焊接条件 摩擦特征 制动复合材料
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Primary biliary cirrhosis in HBV and HCV patients:Clinical characteristics and outcome 被引量:8
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作者 Eirini I Rigopoulou Kalliopi Zachou +3 位作者 Nikolaos K Gatselis Georgia Papadamou George K Koukoulis George N Dalekos 《World Journal of Hepatology》 CAS 2013年第10期577-583,共7页
AIM: To present the characteristics, management and outcome of patients with hepatitis B virus(HBV) or hepatitis C virus(HCV) infections concurrent with primary biliary cirrhosis(PBC).METHODS: Since January 2001 to Se... AIM: To present the characteristics, management and outcome of patients with hepatitis B virus(HBV) or hepatitis C virus(HCV) infections concurrent with primary biliary cirrhosis(PBC).METHODS: Since January 2001 to September 2009,we retrospectively evaluated the medical records of all HBV(n = 1493) and HCV patients(n = 526) who are followed in our center for the presence of concurrent PBC. Seventeen patients identified with concurrent viral hepatitis and PBC(8 HCV and PBC; follow-up: 61 ± 37 mo and 9 HBV and PBC; follow-up: 57 ± 38 mo). PBC diagnosis was established if the patients met at least two of the following criteria: positivity for antimitochondrial antibody, elevated cholestatic enzymes and histological lesions of PBC.RESULTS: HCV or HBV diagnosis preceded that of PBC in most patients by many years. PBC diagnosis was based on the presence of antimitochondrial antibody and elevated cholestatic enzymes in all 17 patients,while one third(5/17; 29.4%) experienced severe pruritus many years before diagnosis. Patients with PBC and HBV were significantly younger at diagnosis of PBC compared to patients with PBC and HCV(56.1 ± 11.2vs 68.5 ± 10.3, respectively, P < 0.05). At initial clinical and histological assessment the majority of patients were cirrhotics(10/17; 58.8%) with the group of PBC and HCV carrying the highest frequency(87.5% vs33.3% in PBC and HBV; P < 0.05). The patients with HBV and concomitant PBC seem to have better outcome compared to those with HCV and PBC since none of the 6 non-cirrhotics with HBV and PBC developed cirrhosis during follow-up.CONCLUSION: PBC diagnosis in HBV or HCV patients is very difficult and usually delayed. Therefore, in any case, cholestasis should alert physicians to further search for PBC. 展开更多
关键词 Antimitochindrial ANTIBODIES AUTOIMMUNE liver disease HEPATITIS B VIRUS HEPATITIS c VIRUS Primary BILIARY cirrhosis.
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SR9009联合吲哚丙酸通过核因子κB信号通路减轻C2C12成肌细胞的炎症反应
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作者 姬慧慧 蒋旭 +7 位作者 张志敏 邢运虹 王亮亮 李娜 宋雨庭 罗旭光 崔慧林 曹锡梅 《中国组织工程研究》 CAS 北大核心 2025年第6期1220-1229,共10页
背景:钟基因Rev-erbα参与调节炎症,但激活Rev-erbα会增加心脑血管疾病风险。为降低相关风险,探索Rev-erbα激动剂SR9009联合其他药物来减轻骨骼肌成肌细胞炎症,奠定治疗炎症相关性骨骼肌萎缩的理论基础。目的:探讨脂多糖刺激C2C12成... 背景:钟基因Rev-erbα参与调节炎症,但激活Rev-erbα会增加心脑血管疾病风险。为降低相关风险,探索Rev-erbα激动剂SR9009联合其他药物来减轻骨骼肌成肌细胞炎症,奠定治疗炎症相关性骨骼肌萎缩的理论基础。目的:探讨脂多糖刺激C2C12成肌细胞时吲哚丙酸、SR9009与核因子κB信号通路的关系。方法:①1μg/mL脂多糖刺激C2C12成肌细胞,RNA转录组测序结合KEGG通路富集分析信号通路。②CCK-8法检测C2C12成肌细胞活性,筛选吲哚丙酸的最佳给药浓度;然后将细胞分为空白对照组、脂多糖(1μg/mL)组、SR9009(10μmol/L)+脂多糖组、吲哚丙酸(80μmol/L)+脂多糖组、吲哚丙酸+SR9009+脂多糖组,ELISA检测细胞上清液中白细胞介素6水平,RT-qPCR检测白细胞介素6、肿瘤坏死因子α、Toll样受体4、CD14 mRNA表达,Western blot检测NF-κB p65、p-NF-κB p65蛋白表达。③siRNA敲减Rev-erbα,RT-qPCR评估敲减效率,检测白细胞介素6、肿瘤坏死因子αmRNA表达。结果与结论:①与空白对照组比较,脂多糖时间依赖性抑制成肌细胞融合形成肌管,白细胞介素6、肿瘤坏死因子αmRNA表达水平升高,细胞上清液中白细胞介素6水平显著升高;KEGG通路分析支持脂多糖刺激激活核因子κB信号通路。②吲哚丙酸浓度>80μmol/L时抑制C2C12成肌细胞活性;吲哚丙酸和SR9009通过抑制核因子κB信号通路发挥抗炎作用,降低白细胞介素6、肿瘤坏死因子α、Toll样受体4、CD14 mRNA表达水平,p-NF-κB p65/NF-κB p65蛋白表达比值低于脂多糖组。SR9009联合吲哚丙酸显著降低脂多糖诱导的炎症,Toll样受体4、CD14、白细胞介素6和肿瘤坏死因子αmRNA表达水平进一步下调,p-NF-κB p65/NF-κB p65蛋白表达比值显著低于吲哚丙酸+脂多糖组和SR9009+脂多糖组。③Rev-erbα随脂多糖刺激时间依赖性升高;siRNA敲减Rev-erbα效率达58%以上,成功敲减Rev-erbα后添加脂多糖,白细胞介素6和肿瘤坏死因子αmRNA表达较脂多糖组显著上调。④结果说明,Rev-erbα可以作为调节炎症反应的靶点,SR9009靶向激活Rev-erbα联合吲哚丙酸能抑制核因子κB信号通路显著减轻C2C12成肌细胞的炎症反应,联合抗炎效果优于单独干预。 展开更多
关键词 Rev-erbα SR9009 吲哚丙酸 脂多糖 核因子ΚB信号通路 c2c12成肌细胞
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Isolation and Identification of Triazophos-degrading Bacillus subtilis str. C-Y106 and Its Degradation Characteristics
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作者 陈勇辉 付桂明 +6 位作者 万茵 韩蓓 罗阳帆 王建涛 李红歌 陈建芳 柴建新 《Agricultural Science & Technology》 CAS 2010年第8期77-80,113,共5页
[Objective] The aim was to isolate the triazophos-degrading strain and study its degradation characteristics. [Method] A triazophos-degrading bacterium strain C-Y106 was isolated from sludge in an aeration tank of tri... [Objective] The aim was to isolate the triazophos-degrading strain and study its degradation characteristics. [Method] A triazophos-degrading bacterium strain C-Y106 was isolated from sludge in an aeration tank of triazophos manufacture. Then the strain C-Y106 was identified according to the morphology,physiological and biochemical characteristics,and 16S rRNA sequence analysis. The effect of medium with different nutrients on triazophos-degrading rate by C-Y106 was studied. [Result] The strain C-Y106 was identified as Bacillus subtilis. The strain C-Y106 could grow in the mineral salt medium with 40 mg/L of triazophos as the sole sources of carbon,Nitrogen and Phosphorus. The triazophos-degrading rate was the highest as 76.8% in the mineral salt medium with 40 mg/L of triazophos as the sole source of Phosphorus,after being incubated at 31 ℃,pH 8.0 and 150 r/min for 60 h. [Conclusion] The research had provided theoretical basis for the identification and purification of enzymes for triazophos degradation. 展开更多
关键词 Triazophos-degrading Bacillus subtilis str.c-Y106 Degradation characteristics
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