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Association between Free Triiodothyronine Levels and Peripheral Arterial Disease in Euthyroid Participants 被引量:5
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作者 WANG Po DU Rui +8 位作者 LIN Lin DING Lin PENG Kui XU Yu XU Min BI Yu Fang WANG Wei Qing NING Guang LU Jie Li 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第2期128-133,共6页
这当前的代表性的研究 40 年并且在上面在 euthyroid 汉语人口之中调查在甲状腺荷尔蒙和外部动脉疾病(垫) 之间的关系。浆液免费 triiodothyronine (FT3 ) ,免费甲状腺素(FT4 ) ,刺激甲状腺的荷尔蒙(TSH ) ,和甲状腺抗体被测量。垫... 这当前的代表性的研究 40 年并且在上面在 euthyroid 汉语人口之中调查在甲状腺荷尔蒙和外部动脉疾病(垫) 之间的关系。浆液免费 triiodothyronine (FT3 ) ,免费甲状腺素(FT4 ) ,刺激甲状腺的荷尔蒙(TSH ) ,和甲状腺抗体被测量。垫被定义为脚关节臂的索引(ABI )< 0.9。有 91 (2.9%) 在 3,148 euthyroid 之中的垫案例学习参加者。参加者在有的 FT3 和 free-triiodothyronine-to-free-thyroxin (FT3/FT4 比率) 最高方照流行的垫的减少的风险(调整 multivariate 的机会比率, 95% 信心间隔:0.32, 0.15-0.62,为趋势 = 的 P 0.01 和 0.31, 0.13-0.66,为趋势 = 的 P 0.004,分别地) 与那些相比在里面最低方照。得出结论, FT3 层次和 FT3/FT4 比率相反地 40 年并且在上面在 euthyroid 汉语人口与流行的垫被联系。 展开更多
关键词 PAD Association between free triiodothyronine Levels and Peripheral Arterial Disease in Euthyroid Participants TPOAb HDL SBP LDL TSH FPG
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Free triiodothyronine in relation to coronary severity at different ages: Gensini score assessment in 4206 euthyroid patients 被引量:1
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作者 Bing-Yang ZHOU Yuan-Lin GUO +8 位作者 Na-Qiong WU Cheng-Gang ZHU Ying GAO Ping QING Xiao-Lin LI Yao WANG Geng LIU Qian DONG Jian-Jun LI 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第12期978-983,共6页
为了学习在正常范围以内的免费 triiodothyronine ( FT3 )是否在不同的性和年龄 groups.MethodsA 在冠的动脉疾病( CAD )的存在和严厉上有效果, 4206 个 euthyroid 病人总计连续地被注册并且把组划分了成 CAD ( n = 3306 )并且 非CAD ... 为了学习在正常范围以内的免费 triiodothyronine ( FT3 )是否在不同的性和年龄 groups.MethodsA 在冠的动脉疾病( CAD )的存在和严厉上有效果, 4206 个 euthyroid 病人总计连续地被注册并且把组划分了成 CAD ( n = 3306 )并且 非CAD 组( n = 900 )。所有病人经历了冠的 angiography (CAG ) 。Gensini 分数(GS ) 被用来决定冠的动脉狭窄的严厉。严重 CAD 被定义为 GS > 32 并且温和 CAD 被定义为 GS 32。逻辑回归分析和线性回归分析被进行与不同的性在病人与 CAD 决定 FT3 的协会, FT3 的 ages.ResultsConcentration 在 angiography 正常的控制组比那在有 CAD 的病人是更低的(P < 0.05 ) 。另外, FT3 的集中在温和 CAD 比那在严重 CAD 是更低的。在为传统的心血管的风险因素和潜在的 confounders 调整以后, FT3 否定地与 CAD 的存在被相关,然而并非在老病人(> 65 岁) 。Multivariable 线性回归分析证明 FT3 否定地在正常以内与稳定的 CAD 在男、年轻的病人,然而并非在旧 patients.ConclusionsLow FT3 与 GS 被联系范围否定地在年轻病人,然而并非在旧的与 CAD 的存在和严厉被联系。进一步的研究被需要证实我们的调查结果。 展开更多
关键词 冠的 angiography 冠的动脉疾病 EUTHYROIDISM 免费 triiodothyronine Gensini 分数
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Free triiodothyronine level correlates with statin responsiveness in acute myocardial infarction 被引量:2
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作者 Wen-Yao WANG Kuo ZHANG +3 位作者 Wei ZHAO A. Martin Gerdes Giorgio Iervasi Yi-Da TANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第4期290-297,共8页
BackgroundAlthough 甲状腺荷尔蒙(TH ) 在类脂化合物新陈代谢上有重要效果,在 TH 和 statin 应答之间的关系从来没被调查过。我们假设那 TH 与尖锐心肌的梗塞(AMI ) 在病人在 statin 应答起一个重要作用 .MethodsConsecutive Fuwai 医... BackgroundAlthough 甲状腺荷尔蒙(TH ) 在类脂化合物新陈代谢上有重要效果,在 TH 和 statin 应答之间的关系从来没被调查过。我们假设那 TH 与尖锐心肌的梗塞(AMI ) 在病人在 statin 应答起一个重要作用 .MethodsConsecutive Fuwai 医院(中国北京) 里的 1091 个就医的 AMI 病人被注册进这当前的研究。学习人口基于 statin 治疗的紧张被划分成三个组:低紧张(n = 221 ) ,中等紧张(n = 712 ) 并且高紧张(n = 158 ) 。类脂化合物层次在 statin 治疗持续 10-14 天以后被测量。在 TH ,类脂化合物侧面层次和降低目标的低密度的脂蛋白胆固醇( LDL-C )的成就之间的协会在 statin therapy.ResultsBy 上与 AMI 在病人被探索一般线性分析,在免费 triiodothyronine ( FT3 )和 LDL-C 水平之间的一个重要线性趋势(线性系数 r =-0.082, P = 0.001 )并且 FT3 和全部的胆固醇( TC )铺平( r =-0.105, P = 0.031 )在中等紧张的 statin 组被观察。一个更明显的线性趋势在高紧张的 statin 组被检测(为 LDL-C:r =-0.113, P = 0.005;为 TC:r =-0.172, P = 0.029,分别地) 。然而,没有重要关联在低紧张的 statin 组被观察。与 low-FT3 组相比(定义为 FT3 < 1.79 pg/mL ) ,为达到 LDL-C 的 OR (95% CI )< 3.0mmol/L 被发现是 2.217 (1.001-4.839 ) 在更高的 FT3 组织(> 2.95 pg/mL ) 。为达到更集中的目标的 OR (95% CI )(LDL-C < 1.8mmol/L ) 是 2.836 (1.014-5.182 ).ConclusionsOur 学习表明在 FT3 层次的那个变化与在 AMI 病人的 statins 的胆固醇阴沉的应答有关。这些调查结果建议低 FT3 可以是因缺乏 LDL-C 目标成就和病人穷人应答负责的一个因素到 statin 治疗。 展开更多
关键词 应答 梗塞 心肌 免费 关联 类脂化合物 线性分析 线性趋势
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A solid phase radioimmunoassay for free triiodothyronine in serum:assay development and validation 被引量:1
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作者 LIU Fangyan ZHOU Meiying +2 位作者 YIN Linxiang YANG Jianzhong HUA Chenglin (Shanghai Institute of Nuclear Research, the Chinese Academy of Sciences, Shanghai 201800 ) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1999年第1期44-47,共4页
A solid phase radioimmunoassay for free triiodothyronine in serum was developed based on double-antibody coated tubes. The method was turned out to be reliable with good reproducibility, higher sensitivity and easy pe... A solid phase radioimmunoassay for free triiodothyronine in serum was developed based on double-antibody coated tubes. The method was turned out to be reliable with good reproducibility, higher sensitivity and easy performance. The measurable range of FT3 in serum was 1.2 to 38 pmol/L. The mean coefficients of variation within and between assays were 1.79%-3.18% and 4.72%-9.31%, respectively. The FT3 concentrations in euthyroid serum as determined by this method were 2.8 to 7.8pmol/L. The FT3 values determined by this new method correlated well with those measured by a commercial radioimmunoassay (r=0.853). 展开更多
关键词 血清 固相 三碘甲状腺原氨酸 放射免疫测定
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CONVEXITY OF THE FREE BOUNDARY FOR AN AXISYMMETRIC INCOMPRESSIBLE IMPINGING JET
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作者 王晓慧 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期234-246,共13页
This paper is devoted to the study of the shape of the free boundary for a threedimensional axisymmetric incompressible impinging jet.To be more precise,we will show that the free boundary is convex to the fluid,provi... This paper is devoted to the study of the shape of the free boundary for a threedimensional axisymmetric incompressible impinging jet.To be more precise,we will show that the free boundary is convex to the fluid,provided that the uneven ground is concave to the fluid. 展开更多
关键词 Euler system axisymmetric impinging jet INCOMPRESSIBLE free boundary CONVEXITY
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GLOBAL SOLUTIONS TO 1D COMPRESSIBLE NAVIER-STOKES/ALLEN-CAHN SYSTEM WITH DENSITY-DEPENDENT VISCOSITY AND FREE-BOUNDARY
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作者 丁时进 李颖花 王喻 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期195-214,共20页
This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depen... This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depends on the density in the form ofη(ρ)=ρ^(α).The existence of unique global H^(2m)-solutions(m∈N)to the free boundary problem is proven for when 0<α<1/4.Furthermore,we obtain the global C^(∞)-solutions if the initial data is smooth. 展开更多
关键词 Navier-Stokes/Allen-Cahn system density-dependent viscosity free boundary global solutions
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Yolk free egg substitute improves the serum phospholipid profile of mice with metabolic syndrome based on lipidomic analysis
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作者 Zhihui Yu Lingyu Fan +3 位作者 Fei Tai Lixin Zhang Xiaoyu Zhang Yisheng Chen 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期482-493,共12页
In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with wh... In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in serum.It was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein cholesterol.YFES exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened out.Carnitine C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to WE.YFES reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C levels.To sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism. 展开更多
关键词 Metabolic syndrome Whole egg Yolk free egg substitute SERUM LIPIDOMICS
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A novel efficient energy absorber with free inversion of a metal foam-filled circular tube
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作者 Jianxun ZHANG Jinwen BAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期1-14,共14页
In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analyticall... In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analytically and numerically. The theoretical analysis reveals that the energy is mainly dissipated through the radial bending of the metal circular tube, the circumferential expansion of the metal circular tube, and the metal filled-foam compression. The principle of energy conservation is used to derive the theoretical formula for the minimum compressive force of the MFFCT over free inversion under axial loading. Furthermore, the free inversion deformation characteristics of the MFFCT are analyzed numerically. The theoretical steady values are found to be in good agreement with the results of the finite element(FE) analysis. The effects of the average diameter of the metal tube, the wall thickness of the metal tube, and the filled-foam strength on the free inversion deformation of the MFFCT are considered. It is observed that in the steady deformation stage, the load-carrying and energy-absorbing capacities of the MFFCT increase with the increase in the average diameter of the metal tube, the wall thickness of the metal tube, or the filled-foam strength. The specific energy absorption(SEA) of free inversion of the MFFCT is significantly higher than that of the metal tube alone. 展开更多
关键词 metal foam-filled circular tube(MFFCT) free inversion load-carrying capacity energy absorption
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Estimation of free core nutation parameters and availability of computing options
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作者 Weiwei Yang Xiaoming Cui +2 位作者 Jianqiao Xu Qingchao Liu Ming Qin 《Geodesy and Geodynamics》 EI CSCD 2024年第1期61-74,共14页
The Earth’s Free Core Nutation(FCN) causes Earth tides and forced nutation with frequencies close to the FCN that exhibit resonance effects.High-precision superconducting gravimeter(SG) and very long baseline interfe... The Earth’s Free Core Nutation(FCN) causes Earth tides and forced nutation with frequencies close to the FCN that exhibit resonance effects.High-precision superconducting gravimeter(SG) and very long baseline interferometry(VLBI) provide good observation techniques for detecting the FCN parameters.However,some choices in data processing and solution procedures increase the uncertainty of the FCN parameters.In this study,we analyzed the differences and the effectiveness of weight function and ocean tide corrections in the FCN parameter detection using synthetic data,SG data from thirty-one stations,and the 10 celestial pole offset(CPO) series.The results show that significant discrepancies are caused by different computing options for a single SG station.The stacking method,which results in a variation of0.24-5 sidereal days(SDs) in the FCN period(T) and 10^(3)-10^(4) in the quality factor(Q) due to the selection of the weighting function and the ocean tide model(OTM),can effectively suppress this influence.The statistical analysis results of synthetic data shows that although different weight choices,while adjusting the proportion of diurnal tidal waves involved,do not significantly improve the accuracy of fitted FCN parameters from gravity observations.The study evaluated a series of OTMs using the loading correction efficiency.The fitting of FCN parameters can be improved by selecting the mean of appropriate OTMs based on the evaluation results.Through the estimation of the FCN parameters based on the forced nutation,it was found that the weight function P_(1) is more suitable than others,and different CPO series(after 2009) resulted in a difference of 0.4 SDs in the T and of 103 in the Q.We estimated the FCN parameters for SG(T=430.4±1.5 SDs and Q=1.52×10^(4)±2.5×10^(3)) and for VLBI(T=429.8±0.7 SDs,Q=1.88×10^(4)±2.1×10^(3)). 展开更多
关键词 free core nutation Superconducting gravimeter Very long baseline interferometry Weight function Ocean tide model
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Method of fabricating artificial rock specimens based on extrusion free forming(EFF)3D printing
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作者 Xiaomeng Shi Tingbang Deng +2 位作者 Sen Lin Chunjiang Zou Baoguo Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1455-1466,共12页
Three-dimensional(3D)printing technology has been widely used to create artificial rock samples in rock mechanics.While 3D printing can create complex fractures,the material still lacks sufficient similarity to natura... Three-dimensional(3D)printing technology has been widely used to create artificial rock samples in rock mechanics.While 3D printing can create complex fractures,the material still lacks sufficient similarity to natural rock.Extrusion free forming(EFF)is a 3D printing technique that uses clay as the printing material and cures the specimens through high-temperature sintering.In this study,we attempted to use the EFF technology to fabricate artificial rock specimens.The results show the physico-mechanical properties of the specimens are significantly affected by the sintering temperature,while the nozzle diameter and layer thickness also have a certain impact.The specimens are primarily composed of SiO_(2),with mineral compositions similar to that of natural rocks.The density,uniaxial compressive strength(UCS),elastic modulus,and tensile strength of the printed specimens fall in the range of 1.65–2.54 g/cm3,16.46–50.49 MPa,2.17–13.35 GPa,and 0.82–17.18 MPa,respectively.It is capable of simulating different types of rocks,especially mudstone,sandstone,limestone,and gneiss.However,the simulation of hard rocks with UCS exceeding 50 MPa still requires validation. 展开更多
关键词 Artificial rock 3D printing Extrusion free forming(EFF) Similarity analysis Mechanical properties
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Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network
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作者 YANG Luyi LI Haiyang +1 位作者 ZHANG Jin ZHU Yuehe 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期495-508,共14页
It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly eval... It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model. 展开更多
关键词 manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency
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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers
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作者 H.M.FEIZABAD M.H.YAS 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期543-562,共20页
Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent years.Bamboo fibers ar... Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent years.Bamboo fibers are renowned for their good mechanical properties,abundance,and short cycle growth.As beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic foundation.Three different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the thickness.The elastic properties of the composite are determined with the law of mixture.Employing Hamilton’s principle,the governing equations of motion are obtained.The generalized differential quadrature method(GDQM)is then applied to the equations to obtain the results.The achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam change.Furthermore,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber distribution.Eventually,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams. 展开更多
关键词 bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)
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PAPP-A、Free-β-HCG与子痫前期的相关性分析
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作者 杨柳 杨晓彦 《浙江临床医学》 2024年第3期433-434,共2页
目的 探讨妊娠相关血浆蛋白A(PAPP-A)、游离β-人绒毛膜促性腺激素(Free-β-HCG)与子痫前期的相关性。方法 收集2021年1月至2023年1月548例有妊娠结局且孕期行血清学筛查孕妇的临床资料。依据是否发生子痫分为子痫前期组与正常孕妇组,... 目的 探讨妊娠相关血浆蛋白A(PAPP-A)、游离β-人绒毛膜促性腺激素(Free-β-HCG)与子痫前期的相关性。方法 收集2021年1月至2023年1月548例有妊娠结局且孕期行血清学筛查孕妇的临床资料。依据是否发生子痫分为子痫前期组与正常孕妇组,分析两组孕妇一般资料及血清学筛查指标。结果 子痫前期组孕妇PAPP-A低于正常孕妇组,差异有统计学意义(P<0.05);而子痫前期组孕妇Free-β-HCG与正常孕妇组比较,差异无统计学意义(P<0.05);PAPP-A、Free-β-HCG用于筛查子痫前期的ROC曲线下面积为0.603、0.548。结论 血清学筛查指标PAPP-A与子痫前期密切相关,其可作为预测子痫前期发生的指标。 展开更多
关键词 血清学筛查 子痫前期 PAPP-A free-Β-HCG
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Innovative Exploration and Research on International Exchange and Cooperation Mechanisms under the Background of Hainan Free Trade Port
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作者 Xiaochao Yao 《Proceedings of Business and Economic Studies》 2024年第1期150-154,共5页
In order to explore and foster innovation in international exchange and cooperation,this study focuses on the background of the construction of the Hainan Free Trade Port.It delves into the current development status,... In order to explore and foster innovation in international exchange and cooperation,this study focuses on the background of the construction of the Hainan Free Trade Port.It delves into the current development status,characteristic demands,and potential challenges of its international exchange and cooperation mechanisms.Through a comprehensive analysis of relevant cases,survey questionnaires,and literature,this study aims to provide feasible innovative models and recommendations to promote the sustained development of the Hainan Free Trade Port in the field of international exchange and cooperation,injecting new vitality into China’s economic globalization.This exploration contributes to a deeper understanding of the development of free trade ports and provides insights and references for other countries and regions. 展开更多
关键词 free trade port International exchange Cooperation mechanism
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基于一种距离相关的超高维生存数据Model-Free特征筛选
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作者 潘莹丽 王昊宇 +1 位作者 喻佳丽 刘展 《湖北大学学报(自然科学版)》 CAS 2024年第1期122-132,共11页
随着大数据时代的来临,数据维度爆炸式增长,超高维数据的降维问题逐渐成为众多研究领域的热点话题。由于响应变量通常存在右删失,处理超高维完全数据的降维方法在右删失数据中将不再适用。本研究提出一种新的基于距离相关能有效处理超... 随着大数据时代的来临,数据维度爆炸式增长,超高维数据的降维问题逐渐成为众多研究领域的热点话题。由于响应变量通常存在右删失,处理超高维完全数据的降维方法在右删失数据中将不再适用。本研究提出一种新的基于距离相关能有效处理超高维右删失数据的特征筛选方法。首先利用距离相关系数计算每个协变量对响应变量的边际效应,建立与该系数有关的筛选指标,然后再根据事先确立的筛选准则进行特征筛选。提出的特征筛选方法不依赖任何模型结构假定,因此可以有效避免模型指定错误带来的不良后果。此外,该方法采用的距离协方差估计量是总体距离协方差的一个无偏估计,统计准确性和计算精度高。模拟和实证研究表明,提出的方法能在保留所有重要变量的前提下快速剔除与响应变量相关程度较弱的协变量,从而达到降低参数维数的目的。 展开更多
关键词 超高维数据 生存数据 距离相关 Model-free特征筛选
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Prognostic value of free triiodothyronine in patients with dilated cardiomyopathy 被引量:2
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作者 Hong-Yan Zhao Ling Sun +5 位作者 Ye-Qian Zhu Qiu-Shi Chen Wen-Wu Zhu Mohammad Bilaal Toorabally Xin-Guang Chen Feng-Xiang Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第18期2170-2176,共7页
Background:The association between free triiodothyronine(FT3)and long-term prognosis in dilated cardiomyopathy(DCM)patients has not been evaluated.The purpose of this study was to determine whether the level of FT3 co... Background:The association between free triiodothyronine(FT3)and long-term prognosis in dilated cardiomyopathy(DCM)patients has not been evaluated.The purpose of this study was to determine whether the level of FT3 could provide prognostic value in patients with DCM.Methods:Data of consecutive patients diagnosed with DCM were collected from October 2009 to December 2014.FT3 was measured by fluoroimmunoassay.Other biochemical markers,such as free thyroxin(FT4),thyroid-stimulating hormone,red blood cell,hemoglobin,blood urea nitrogen,and serum creatinine,were tested at the same time.Follow-up was performed every 3 months.The primary endpoint was all-cause mortality.Pearson analysis was used to evaluate the correlation of FT3 and other lab metrics with DCM patients’prognosis.The association of long-term mortality in DCM and FT3 was compared using Cox hazards model.Results:Data of 176 patients diagnosed with DCM were collected.Of them,24 patients missed FT3 values and six patients were lost to follow-up.Altogether,data of 146 patients were analyzed.During the median follow-up time of 79.9(53.5-159.6)months,nine patients lost,61 patients died(non-survival group),and 85 patients survived(survival group).FT3 was significantly lower in non-survival group than that in survival group(3.65±0.83 pmol/L vs.4.36±1.91 pmol/L;P=0.003).FT3 also showed a significantly positive correlation with red blood cell and hemoglobin,negatively correlated with age,blood urea nitrogen and serum creatinine(P<0.05),respectively.Patients in the group of lower FT3 levels(FT3≤3.49 pmol/L)suffered from a higher risk of all-cause mortality(P for log-rank=0.001).In multivariate Cox regression analysis,FT3 level was significantly associated with all-cause mortality(hazard ratio:0.70,95%confidence interval 0.52-0.95,P for trend=0.021).Conclusion:Low levels of FT3 were associated with increased all-cause mortality in patients with DCM. 展开更多
关键词 Dilated cardiomyopathy free triiodothyronine All-cause mortality
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基于anchor-free的光学遥感舰船关重部位检测算法
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作者 张冬冬 王春平 付强 《北京航空航天大学学报》 EI CAS CSCD 2024年第4期1365-1374,共10页
针对基于深度学习的遥感舰船检测算法存在精细化程度不足、检测效率低的问题,提出一种基于anchor-free的光学遥感舰船关重部位检测算法。所提算法以全卷积的单阶段目标检测(FCOS)算法为基准,在主干网络中引入全局上下文模块,提高网络的... 针对基于深度学习的遥感舰船检测算法存在精细化程度不足、检测效率低的问题,提出一种基于anchor-free的光学遥感舰船关重部位检测算法。所提算法以全卷积的单阶段目标检测(FCOS)算法为基准,在主干网络中引入全局上下文模块,提高网络的特征表达能力;为更好地描述目标的方向性,在预测阶段构建了具有方向表征能力的回归分支;对中心度函数进行优化,使其具备方向感知和自适应能力。实验结果表明:在自建舰船关重部位数据集和HRSC2016上,所提算法的平均精度(AP)比FCOS算法有显著提升;与其他算法相比,所提算法在检测速度和检测精度上均表现优越,具有较高的检测效率。 展开更多
关键词 深度学习 遥感图像 anchor-free 舰船检测 关重部位检测 全卷积单阶段检测
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Anchor free与Anchor base算法结合的拥挤行人检测方法 被引量:1
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作者 谢明鸿 康斌 +1 位作者 李华锋 张亚飞 《电子与信息学报》 EI CSCD 北大核心 2023年第5期1833-1841,共9页
由于精度相对较高,Anchor base算法目前已成为拥挤场景下行人检测的研究热点。但是,该算法需要手工设计锚框,限制了其通用性。同时,单一的非极大值抑制(NMS)筛选阈值作用于不同密度的人群区域会导致一定程度的漏检和误检。为此,该文提... 由于精度相对较高,Anchor base算法目前已成为拥挤场景下行人检测的研究热点。但是,该算法需要手工设计锚框,限制了其通用性。同时,单一的非极大值抑制(NMS)筛选阈值作用于不同密度的人群区域会导致一定程度的漏检和误检。为此,该文提出一种Anchor free与Anchor base检测器相结合的双头检测算法。具体地,先利用Anchor free检测器对图像进行粗检测,将粗检测结果进行自动聚类生成锚框后反馈给区域建议网络(RPN)模块,以代替RPN阶段手工设计锚框的步骤。同时,通过对粗检测结果信息的统计可得到不同区域人群的密度信息。该文设计一个行人头部-全身互监督检测框架,利用头部检测结果与全身的检测结果互相监督,从而有效减少被抑制与漏检的目标实例。提出一种新的NMS算法,该方法可以自适应地为不同密度的人群区域选择合适的筛选阈值,从而最大限度地减少NMS处理引起的误检。所提出的检测器在CrowdHuman数据集和CityPersons数据集进行了实验验证,取得了与目前最先进的行人检测方法相当的性能。 展开更多
关键词 行人检测 Anchor base Anchor free 非极大值抑制
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Free triiodothyronine level indicates the degree of myocardial injury in patients with acute ST-elevation myocardial infarction 被引量:21
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作者 Wang Wen-yao Tang Yi-da +4 位作者 Yang Min Cui Cheng Mu Mu Qian Jie Yang Yue-jin 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第20期3926-3930,共5页
关键词 心肌梗死 心肌损伤 ST 急性 甲状腺功能减退 T3 游离 心脏疾病
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Serum Total Triiodothyronine versus Free Tetraiodothyronine and TSH in Patients with HCV Related Cirrhosis and Their Correlation to the Severity of Cirrhosis 被引量:2
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作者 Ashraf A. Hammam Amal A. Jouda Mona E. Hashem 《Open Journal of Gastroenterology》 2016年第3期75-82,共8页
Background and Aim: The levels of thyroid hormones and their binding proteins are altered in patient with cirrhosis. We aim to study the changes in triiodothyronine level in HCV related cirrhosis and its correlation t... Background and Aim: The levels of thyroid hormones and their binding proteins are altered in patient with cirrhosis. We aim to study the changes in triiodothyronine level in HCV related cirrhosis and its correlation to the severity of liver decompensation. Patients and Methods: This study included seventy two patients with HCV related cirrhosis in three groups Group I: 24 patients with Child A class Group II: 24 patients with Child B and C classes without hepatic encephalopathy Group III: 24 patients with Child B and C classes with hepatic encephalopathy. Results: T3 level was significantly lower in group III than group I and II (0.74 ng/ml vs 1 and 1.3 ng/ml in group II and I in succession). The correlation between Child’s score and T3 level was highly significant (r = -0.64, P < 0.001). Conclusion: Triiodothyronine level is lower in cirrhosis and its level is correlated to the severity of decompensation. 展开更多
关键词 free T4 TSH Clinical Euthyroid CIRRHOSIS HCV
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