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Evaluation of NASA GISS Post-CMIP5 Single Column Model Simulated Clouds and Precipitation Using ARM Southern Great Plains Observations 被引量:3
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作者 Lei ZHANG Xiquan DONG +2 位作者 Aaron KENNEDY Baike XI Zhanqing LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第3期306-320,共15页
The planetary boundary layer turbulence and moist convection parameterizations have been modified recently in the NASA Goddard Institute for Space Studies (GISS) Model E2 atmospheric general circulation model (GCM;... The planetary boundary layer turbulence and moist convection parameterizations have been modified recently in the NASA Goddard Institute for Space Studies (GISS) Model E2 atmospheric general circulation model (GCM; post-CMIP5, hereafter P5). In this study, single column model (SCM_P5) simulated cloud fractions (CFs), cloud liquid water paths (LWPs) and precipitation were compared with Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) groundbased observations made during the period 2002-08. CMIP5 SCM simulations and GCM outputs over the ARM SGP region were also used in the comparison to identify whether the causes of cloud and precipitation biases resulted from either the physical parameterization or the dynamic scheme. The comparison showed that the CMIP5 SCM has difficulties in simulating the vertical structure and seasonal variation of low-level clouds. The new scheme implemented in the turbulence parameterization led to significantly improved cloud simulations in P5. It was found that the SCM is sensitive to the relaxation time scale. When the relaxation time increased from 3 to 24 h, SCM_P5-simulated CFs and LWPs showed a moderate increase (10%-20%) but precipitation increased significantly (56%), which agreed better with observations despite the less accurate atmospheric state. Annual averages among the GCM and SCM simulations were almost the same, but their respective seasonal variations were out of phase. This suggests that the same physical cloud parameterization can generate similar statistical results over a long time period, but different dynamics drive the differences in seasonal variations. This study can potentially provide guidance for the further development of the GISS model. 展开更多
关键词 single column model model evaluation cloud fraction turbulence parameterization
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A Sensitivity Study of Single Column Model
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作者 董敏 许秦 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1996年第3期313-324,共12页
A single column model (SCM) is constructed by extracting the physical subroutines from the NCAR Community Climate Model version 1 (CCM1).Simulated data are generated by CCM1 and used to validate the SCM and to study t... A single column model (SCM) is constructed by extracting the physical subroutines from the NCAR Community Climate Model version 1 (CCM1).Simulated data are generated by CCM1 and used to validate the SCM and to study the sensitivity of the SCM to errors in its input data.It is found that the SCM temperature predictions are moderately sensitive to errors in the input horizontal temperature flux convergence and moisture flux convergence.Two types of error are concerned in this study,random errors due to insufficient data resolution,and errors due to insufficient data area coverage.While the first type of error can be reduced by filtering and/or increasing the data resolution,it is shown that the second type of error can be reduced by enlarging the data area coverage and using a suitable method to compute the input flux convergence terms. 展开更多
关键词 Single column model Input data errors Sensitivity study
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PUMPING AT STEADY CUMULUS BASE AND HALTINER'S AIR COLUMN MODEL
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作者 王沛霖 《Acta meteorologica Sinica》 SCIE 1989年第5期653-660,共8页
It is presented that there is a pumping effect at its base in the development process of a cumulus.In the strongest stage of cumulus development,the pumping is mainly produced by the buoyance at the base,and may be ta... It is presented that there is a pumping effect at its base in the development process of a cumulus.In the strongest stage of cumulus development,the pumping is mainly produced by the buoyance at the base,and may be taken as the first approximation of the ascending speed at the base. The results of numerical calculations and simulations of four observed radar echoes show that as the first approximation,the height of air-mass cumulus may be simulated by Haltiner model in the absence of ob- served ascending speeds at the base,and the Haltiner model can be characterized by the sensitivity of the cumulus development to the virtual temperature excess over environment at the base. 展开更多
关键词 PUMPING AT STEADY CUMULUS BASE AND HALTINER’S AIR column model AT 牙户
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Experimental investigation and modeling of flotation column for treatment of oily wastewater 被引量:11
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作者 Ran Jincai Liu Jiongtian +2 位作者 Zhang Chunjuan Wang Dengyue Li Xiaobing 《International Journal of Mining Science and Technology》 SCIE EI 2013年第5期665-668,共4页
A unique cyclonic static microbubble flotation column was developed for oily wastewater separation.The separation effciency was found to be highly dependent on gas holdup and bubble size distribution.By changing the c... A unique cyclonic static microbubble flotation column was developed for oily wastewater separation.The separation effciency was found to be highly dependent on gas holdup and bubble size distribution.By changing the circulation pressure,gas flow rate,frother concentration,the effect of operation parameters on gas holdup and oil removal effciency were attained.A mathematical modeling between the kinetic constant and the gas holdup was established for oily water separation process.The results show that higher gas holdup and smaller microbubble sizes are benefcial to improve oil removal effciency. 展开更多
关键词 Oily wastewater SEPARATION Floatation column modelING
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Model Experiment on Integral Seismic Behavior of Reinforced Concrete Frame with Split Columns
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作者 李忠献 景萌 +1 位作者 郝永昶 康谷贻 《Transactions of Tianjin University》 EI CAS 2005年第6期412-416,共5页
Based on a series of previous studies, an experiment on the integral seismic behavior of a 1/3 scaled model of two-bay and three-story reinforced concrete frame with split columns at lower two stories is performed und... Based on a series of previous studies, an experiment on the integral seismic behavior of a 1/3 scaled model of two-bay and three-story reinforced concrete frame with split columns at lower two stories is performed under cyclic loading. The original columns at lower two stories of the model frame are short columns and they are replaced by the split columns. The hysteresis curves between the horizontal cyclic load and the lateral displacement at the top of the model frame, indicate that under the cyclic loading, the model frame undergoes the process of cracking, yielding, and maximum loading before being destroyed at the ultimate load. They also indicate that the model frame has better ductility, and the ratio of the ultimate displacement to the yielding displacement, reaches 6.0. The yielding process of the model frame shows that for the frame with split columns, plastic hinges are generated at the ends of beams and then the columns begin yielding while the frame still possesses the bearing and deformation capacity. The design idea of directly changing the short column to long one in the reinforced concrete frame may be realized by replacing the short column with the split one. 展开更多
关键词 reinforced concrete frame seismic behavior split column short column model experiment
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Tropospheric NO_2 Columns over Northeastern North America: Comparison of CMAQ Model Simulations with GOME Satellite Measurements 被引量:5
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作者 石春娥 张宝宁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第1期59-71,共13页
We present comparisons of the NO2 regional Chemical Transport Model (CTM) simulations over North-eastern North America during the time period from May to September, 1998 with hourly surface NO2 observations and the ... We present comparisons of the NO2 regional Chemical Transport Model (CTM) simulations over North-eastern North America during the time period from May to September, 1998 with hourly surface NO2 observations and the NO2 columns retrieved from the GOME (Global Ozone Monitoring Experiment) satellite instrument. The model calculations were performed using the Mesoscale Meteorological Model 5 (MM5), Sparse Matrix Operator Kernal Emissions (SMOKE), and Community Multiscale Air Quality (CMAQ) modeling systems, using the emission data from the National Emissions Inventory (NEI) databases of 1996 (U.S.) and 1995 (Canada). The major objectives were to assess the performance of the CMAQ model and the accuracy of the emissions inventories as they affected the simulations of this important short-lived atmospheric species. The modeled (NcMAQ) and measured (NGOME) NO2 column amounts, as well as their temporal variations, agreed reasonably well. The absolute differences (NcMAQ-NGOME) across the domain were between ±3.0×10^15 molecules cm^-2, but they were less than ±1.0×10^15 molecules cm^-2 over the majority (80%) of the domain studied. The overall correlation coefficient between the measurements and the simulations was 0.75. The differences were mainly ascribed to a combination of inaccurate emission data for the CTM and the uncertainties in the GOME retrievals. Of these, the former were the more easily identifiable. 展开更多
关键词 GOME modelS-3/CMAQ NO2 troposphere column content
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Comparative efficiency analysis of different nonlinear modelling strategies to simulate the biaxial response of RC columns 被引量:2
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作者 Hugo Rodrigues Humberto Varum +1 位作者 António Arêde Aníbal Costa 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第4期553-566,共14页
The performance of different nonlinear modelling strategies to simulate the response of RC columns subjected to axial load combined with cyclic biaxial horizontal loading is compared. The models studied are classified... The performance of different nonlinear modelling strategies to simulate the response of RC columns subjected to axial load combined with cyclic biaxial horizontal loading is compared. The models studied are classified into two categories according to the nonlinearity distribution assumed in the elements: lumped-plasticity and distributed inelasticity. For this study, results of tests on 24 columns subjected to cyclic uniaxial and biaxial lateral displacements were numerically reproduced. The analyses show that the global envelope response is satisfactorily represented with the three modelling strategies, but significant differences were found in the strength degradation for higher drift demands and energy dissipation. 展开更多
关键词 RC columns non-linear behaviour biaxial bending fibre modelling
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A new mathematical model for soil-column experiment and parameter identification
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作者 Gongsheng LI De YAO +2 位作者 Fugui YANG Xiaoqin WANG Hongliang LIU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期210-210,共1页
关键词 土壤实验 非线性 数学模型 地下水 浓缩 土壤化学
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Modelling and Sizing of a Floor Reinforced by Ballasted Columns Intended to Support a Tank
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作者 Cheikh Diallo Diène Madièye Fall Souka Bidzha Harlin Sylvaire 《Open Journal of Civil Engineering》 2024年第3期405-420,共16页
This work aims to study the modeling and sizing of a floor reinforced by ballasted columns. We are studying the system of reinforcement by ballasted columns because this technique is able to replace deep foundations t... This work aims to study the modeling and sizing of a floor reinforced by ballasted columns. We are studying the system of reinforcement by ballasted columns because this technique is able to replace deep foundations that are technically difficult to realize and their cost is higher. The modelling and dimensioning of foundations on a ballasted column will be an important contribution to the state of the art of this method because it will highlight the mode of transfer of loads, and will expose the induced deformations by also allowing to verification criteria of bearing capacity and allowable settlement according to geometric information of the model. The columns on a substrate located at 9 m have a length of 9 m and a diameter of 40 cm and were obtained by incorporating ballast of granular class 0/31.5 of internal friction angle of 38˚ and a density weight of 21 kN/m3. The choice of this method is based on the geotechnical characteristics of the initial soil. Thus, identification and characterization tests were carried out to estimate the bearing capacity and the settlement giving respectively 125 kPa and 57 cm. These results show the ground does not have sufficient mechanical properties to withstand the loads transmitted by the tank. By adopting the reinforcement of the soil with ballasted columns, numerical calculations show that after applying a load equal to 265.1 KPa, 20 cm vertical settlement and 17 cm horizontal displacement were obtained. This is in the tolerable deformation range for our tank, namely, less than 20 cm. Analytically, in addition to reducing settlement, ballasted columns, Due to their high stiffness, they have effectively contributed to the increase of the permissible soil stress up to 257 kPa. 展开更多
关键词 REINFORCEMENT Ballasted columns Reservoir Geotechnical modeling Plaxis 2D
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Restoring-force model of modified RAC columns with silica fume and hybrid fiber 被引量:3
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作者 YANG Tao WANG She-liang LIU Wei 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2674-2684,共11页
In order to establish a restoring-force model for modified concrete columns with recycled aggregates concrete(RAC), cyclic loading tests were carried out on five concretes with RAC columns and ordinary concrete frame ... In order to establish a restoring-force model for modified concrete columns with recycled aggregates concrete(RAC), cyclic loading tests were carried out on five concretes with RAC columns and ordinary concrete frame columns under the combined influence with different admixtures and admixtures ratios(silica fume and hybrid fiber). The expressions for characteristic nodes of the skeleton curve were given by the analysis and numerical regression of the test results. In addition, the hysteretic rules of the restoring-force model and the expression for unloading stiffness were presented. Finally, we summed up the complete calculation method of the hysteretic restoring force, whose results were in good agreement with experiment. The results demonstrated that the proposed model could simulate and reflect the corresponding hysteretic behaviors, and the calculation method can provide the theoretical basis for the engineering application. 展开更多
关键词 MODIFIED RAC columnS skeleton curve unloading stiffness hysteretic rule restoring-force model
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Corrected Phenomenological Model for Break Curves in Fixed-bed Columns: Case of Sb(Ⅲ)
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作者 Gerardo Cifuentes Cristian Guerra +1 位作者 Jorge Manriquez Marco Cifuentes 《材料科学与工程(中英文A版)》 2014年第1期10-17,共8页
关键词 突破曲线 锑(Ⅲ) 唯象模型 固定床 离子交换树脂 案例 纠正 初始浓度
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Experimental Determination and Modeling of Bubble Size Distributions in Bubble Columns 被引量:1
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作者 H.F.Svendsen 罗和安 +1 位作者 K.W.Hjarbo H.A.Jakobsen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1998年第1期33-45,共13页
Using a five point conductivity technique local values of bubble size,bubble velocity and gas fractionhave been experimentally determined in a 288 mmID and 4.3 m high bubble column as a function of axial andradial pos... Using a five point conductivity technique local values of bubble size,bubble velocity and gas fractionhave been experimentally determined in a 288 mmID and 4.3 m high bubble column as a function of axial andradial position for the air/water and CO<sub>2</sub>/N<sub>2</sub>/aqueous MDEA systems.The experimental results are comparedwith predictions from a fundamental two-fluid model.The implementation of a non-steady lateral drag term inthe two-fluid model has been shown.In addition to improving the physical realism of the model,it is found togive slight improvements in the predictions of the distributions of local bubble size.Predictions of bubble size arefound in reasonable agreement with experimental values in the heterogeous flow regime,whereas they are stil1found to be unreliable at low gas velocities.Local void predictions are found in reasonable agreement with experi-mental values,but deviations occur in the homogeneous flow regime towards the wall.This is attributed to defi-ciencies in the simplified bubble size 展开更多
关键词 BUBBLE column BUBBLE size distribution VOLUMETRIC VELOCITY gas FRACTION TWO-FLUID model
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Modeling bubble column reactor with the volume of fluid approach:Comparison of surface tension models 被引量:4
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作者 Qi Liu Zhenghong Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2659-2665,共7页
This work aims at comparing surface tension models in VOF(Volume of Fluid) modeling and investigating the effects of gas distributor and gas velocity. Hydrodynamics of a continuous chain of bubbles inside a bubble col... This work aims at comparing surface tension models in VOF(Volume of Fluid) modeling and investigating the effects of gas distributor and gas velocity. Hydrodynamics of a continuous chain of bubbles inside a bubble column reactor was simulated. The grid independence study was first conducted and a grid size of 1.0 mm was adopted in order to minimize the computing time without compromising the accuracy of the results. The predictions were validated by comparing the experimental studies reported in the literature. It was found that all surface tension models can describe the bubble rise and bubble plume in a column with slight deviations. 展开更多
关键词 BUBBLE column reactor Computational FLUID dynamics Volume of FLUID method Surface tension modelS Gas DISTRIBUTOR
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肺腺癌一线化疗患者顺铂化疗抵抗的影响因素及其列线图预测模型的构建
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作者 郭运杰 井小会 +1 位作者 宁飘飘 王瑞琳 《实用癌症杂志》 2026年第1期108-113,共6页
目的探究肺腺癌一线化疗患者顺铂化疗抵抗发生的影响因素,并构建列线图风险预测模型。方法选择104例肺腺癌一线化疗患者作为研究对象,统计患者化疗期间顺铂化疗抵抗发生情况;设计基线资料调查表采集患者的临床资料,采用单因素、多因素Lo... 目的探究肺腺癌一线化疗患者顺铂化疗抵抗发生的影响因素,并构建列线图风险预测模型。方法选择104例肺腺癌一线化疗患者作为研究对象,统计患者化疗期间顺铂化疗抵抗发生情况;设计基线资料调查表采集患者的临床资料,采用单因素、多因素Logistic回归分析肺腺癌患者一线化疗过程中顺铂化疗抵抗发生的影响因素,并构建列线图风险预测模型。绘制受试者工作特征(ROC)曲线验证该模型的预测价值,并绘制决策曲线评估该模型的临床获益情况。结果经4个周期的一线化疗后,顺铂化疗抵抗发生率为41.35%(43/104)。单因素分析结果显示,发生组肿瘤直径大于未发生组,CEA、CA125水平高于未发生组,且营养不良、低分化/未分化、未联合靶向治疗、甲状腺转录因子-1(TTF-1)阴性的患者占比均高于未发生组,差异有统计学意义(P<0.05);多因素Logistic回归分析结果显示:肿瘤直径大、低分化/未分化、营养不良、未联合靶向治疗、TTF-1阴性是肺腺癌一线化疗患者顺铂化疗抵抗发生的独立危险因素(OR>1,P<0.05)。构建列线图风险预测模型,验证模型显示C-index=0.843,具有良好区分度;绘制ROC曲线,结果显示,列线图风险预测模型评估肺腺癌一线化疗患者顺铂化疗抵抗发生的AUC为0.843,AUC的95%置信区间为0.769~0.917,P<0.001,敏感度为0.814,特异度为0.754,约登指数为0.568;绘制决策曲线,结果显示,在阈值0.00~0.87范围内具有更高的净收益率,最大净收益率为0.370,提示该模型具有较好的预测价值。结论肿瘤直径大、低分化/未分化、营养不良、未联合靶向治疗、TTF-1阴性是肺腺癌一线化疗患者顺铂化疗抵抗发生的独立危险因素,基于上述因素构建的列线图风险预测模型可较好预测患者顺铂化疗抵抗发生风险。 展开更多
关键词 肺腺癌 一线化疗 顺铂化疗抵抗 影响因素 列线图 预测模型
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基于DBN-IWOA优化的区间二型TSK模糊逻辑系统在化工过程建模中的应用
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作者 李军 康鹏元 《过程工程学报》 北大核心 2026年第1期99-108,共10页
针对化工过程中存在的强非线性和复杂性问题,本工作提出了一种基于深度信念网络(DBN)与改进鲸鱼优化算法(IWOA)优化的区间二型TSK模糊逻辑系统(DBN-IWOA-IT2 TSK FLS)方法,以提升软测量建模的精度和稳定性。首先,DBN通过深度特征提取能... 针对化工过程中存在的强非线性和复杂性问题,本工作提出了一种基于深度信念网络(DBN)与改进鲸鱼优化算法(IWOA)优化的区间二型TSK模糊逻辑系统(DBN-IWOA-IT2 TSK FLS)方法,以提升软测量建模的精度和稳定性。首先,DBN通过深度特征提取能力对输入数据进行处理,以减少噪声干扰并提取关键信息。随后,结合区间二型TSK模糊逻辑系统(IT2 TSK FLS)的建模优势,采用IWOA算法对前件参数和后件参数进行优化,以进一步增强模型的预测能力。IWOA通过引入早熟收敛检测机制,提高了全局搜索能力,加快了收敛速度,并降低了陷入局部最优的风险。最后,将所提出的方法应用于脱丁烷塔软测量建模,选取了支持向量机(SVM)、长短期记忆网络(LSTM)、门控循环单元网络(GRU),以及分别基于反向传播算法(BP)、粒子群优化算法(PSO)、灰狼优化算法(GWO)、鲸鱼优化算法(WOA)、改进鲸鱼优化算法(IWOA)和DBN-IWOA优化算法的区间二型TSK模糊逻辑系统作为对比模型进行实验评估。结果显示,DBN-IWOA-IT2 TSK FLS在预测准确性、收敛速度均优于现有方法,验证了其有效性和工程应用价值。 展开更多
关键词 软测量建模 脱丁烷塔 区间二型模糊逻辑系统 深度置信网络 早熟收敛检测机制
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乳腺癌术后子宫内膜病变的危险因素及风险预测列线图模型构建与验证研究
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作者 贾麒 俞丽娟 祁发玲 《中国妇产科临床杂志》 北大核心 2026年第1期42-45,共4页
目的探讨乳腺癌术后子宫内膜病变的危险因素并构建风险预测模型。方法选取2018年9月至2021年9月临夏回族自治州人民医院乳腺癌术后患者110例临床资料进行回顾性分析,根据乳腺癌术后随访子宫内膜病变发生情况分为未发生病变组(n=35例)和... 目的探讨乳腺癌术后子宫内膜病变的危险因素并构建风险预测模型。方法选取2018年9月至2021年9月临夏回族自治州人民医院乳腺癌术后患者110例临床资料进行回顾性分析,根据乳腺癌术后随访子宫内膜病变发生情况分为未发生病变组(n=35例)和发生病变组(n=75例)。采用二元Logistic回归分析危险因素并建立预测模型。结果二元Logistic回归模型分析显示,绝经、他莫昔芬使用时间(>5年)、宫腔内高回声占位、AUB/PMB、术前E_(2)、术后E_(2)水平均是乳腺癌术后发生子宫内膜病变的独立影响因素(P<0.05)。列线图模型训练集与验证集AUC分别为0.979(95%CI:0.958~1.000)和0.983(95%CI:0.954~1.000),校准曲线显示预测一致性良好,决策曲线证实其临床实用性。模型内验证准确率为93.6%。结论绝经、他莫昔芬使用时间(>5年)、宫腔内高回声占位、AUB/PMB、术前E_(2)、术后E_(2)水平均是乳腺癌术后发生子宫内膜病变的独立危险因素,基于上述因素构建的预测模型预测价值较好。 展开更多
关键词 乳腺癌 他莫昔芬 子宫内膜病变 危险因素 列线图模型 雌二醇
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多孔排柱式防波堤对复合坡度岛礁规则波水动力特性影响的试验研究
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作者 刘叶文雅 屈科 +2 位作者 王超 李玮 郑伟 《热带地理》 北大核心 2026年第2期358-367,共10页
在全球珊瑚岛礁面临生存困境的情况下,针对真实海底地形开展了关于多孔排柱式防波堤对复合坡度岛礁规则波水动力影响的物理试验研究,分析了单排多孔柱式生态友好型防波堤在不同自身结构(壁面开孔率n)、摆放方式(横向布置间距D、沿礁坪... 在全球珊瑚岛礁面临生存困境的情况下,针对真实海底地形开展了关于多孔排柱式防波堤对复合坡度岛礁规则波水动力影响的物理试验研究,分析了单排多孔柱式生态友好型防波堤在不同自身结构(壁面开孔率n)、摆放方式(横向布置间距D、沿礁坪布置位置距礁缘长度l)以及不同波浪要素(如入射波高H、礁坪水深hr、波浪周期T)下对规则波传播过程产生的影响。试验结果表明:多孔排柱式防波堤显著加强了波浪主频波能量耗散,且使波能分布发生变化;不同波浪要素下防波堤的存在对水体的影响程度不同;防波堤沿礁坪布置位置通过调制波能反射区与透射区的时空分布,显著改变规则波水动力特征,横向布置间距通过改变柱体间隙影响透射波和绕射波的分布与间隙内涡旋耗散对水体影响适中,而壁面开孔率通过调节防波堤透流能力改变局部流场,但对整体波能传递影响最有限。 展开更多
关键词 物理模型 复合坡度岛礁 多孔柱式防波堤 规则波 消波特性
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构建个体化预测支气管哮喘儿童规范治疗停药后复发风险的列线图模型
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作者 李湘云 杨坤良 阳丽琼 《临床肺科杂志》 2026年第1期65-70,共6页
目的探讨支气管哮喘(BA)儿童规范治疗停药后复发的危险因素,并构建个体化预测复发的列线图模型。方法选择2020年6月至2022年9月本院收治的BA患儿,均在规范治疗后停药。对患儿开展1年的随访,了解复发情况并分成复发组和对照组。获取两组... 目的探讨支气管哮喘(BA)儿童规范治疗停药后复发的危险因素,并构建个体化预测复发的列线图模型。方法选择2020年6月至2022年9月本院收治的BA患儿,均在规范治疗后停药。对患儿开展1年的随访,了解复发情况并分成复发组和对照组。获取两组患者资料进行比较,利用多因素分析筛查BA患儿停药后复发的相关因素,并构建预测模型。通过ROC和校准曲线对模型的预测效果(区分度及准确性)予以评估。结果共纳入156例患儿,其中停药后复发91例,复发率为58.33%。复发组合并过敏性鼻炎情况、哮喘程度、治疗方案、ICS疗程、停药前稳定时间及停药时FeNO值和对照组有统计学差异(P<0.05)。Logistic回归筛查出合并过敏性鼻炎(OR=4.288,95%CI:1.801~10.208)、重度或危重度哮喘(OR=6.917,95%CI:2.307~20.736)、ICS疗程<12个月(OR=6.926,95%CI:2.213~21.672)、停药前稳定时间<3个月(OR=4.724,95%CI:1.521~14.669)、停药时FeNO高水平(OR=3.128,95%CI:1.445~6.773)5个预测因子,基于上述因子构建预测停药后复发风险的列线图模型,内部验证显示,ROC曲线下面积(AUC)为0.800(95%CI:0.732~0.868),预测BA患儿停药后复发的概率接近实际概率,拟合优度H-L检验χ^(2)=0.894,P=0.440。结论根据合并过敏性鼻炎情况、哮喘程度、ICS疗程、停药前稳定时间、停药时FeNO值构建的列线图模型可对BA患儿停药后复发风险进行有效预测。 展开更多
关键词 支气管哮喘 儿童 规范化治疗 复发 列线图模型
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老年脊柱手术患者术后谵妄风险预测模型的构建
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作者 尹杨 李宁 +2 位作者 张亚玲 裴永乐 刘媛媛 《新疆医科大学学报》 2026年第1期135-141,共7页
目的 分析老年脊柱手术患者术后谵妄(Postoperative delirium, POD)的危险因素,构建并验证预测模型。方法 选取2024年6月至2025年2月在新疆某三甲医院择期行脊柱手术的老年患者300例,并收集其临床资料。根据术后是否发生谵妄,将患者分为... 目的 分析老年脊柱手术患者术后谵妄(Postoperative delirium, POD)的危险因素,构建并验证预测模型。方法 选取2024年6月至2025年2月在新疆某三甲医院择期行脊柱手术的老年患者300例,并收集其临床资料。根据术后是否发生谵妄,将患者分为POD组和非POD组。采用单因素分析、最小绝对收缩和选择算子(Least absolute shrinkage and selection operator,LASSO)及多因素Logistic回归筛选变量并建立风险预测模型,绘制列线图。采用Hosmer-Lemeshow检验评估模型校准度,受试者工作特征(Receiver operating characteristic,ROC)曲线下面积(Area under curve,AUC)、决策曲线(Decision curve analysis,DCA)及临床影响曲线分别评价模型的区分度、临床有用性与净获益。通过Bootstrap法进行内部验证。结果 与非POD组比较,POD组患者的体质指数(Body mass index, BMI)、术中出血量、手术时长、术后平均红细胞体积(Mean corpuscular volume, MCV)、钠离子浓度(Na+)、葡萄糖与白蛋白比值(Glucose-to-albumin ratio, GAR)、葡萄糖与淋巴细胞比值(Glucose-to-lymphocyte ratio, GLR)、尿素浓度均较高(P均<0.05)。多因素Logistic回归显示,手术时长(OR=1.858,95%CI:1.172~2.945,P=0.008)、术后GLR(OR=1.935,95%CI:1.328~2.819,P=0.001)、GAR(OR=1.230,95%CI:1.074~1.408,P=0.003)、尿素浓度(OR=2.123,95%CI:1.308~3.440,P=0.002)是POD的独立危险因素。基于上述4个变量构建的预测模型,模型ROC-AUC为0.864(95%CI:0.815~0.912),灵敏度为81.5%,特异度为78.3%,内部验证ROC-AUC为0.849(95%CI:0.777~0.921),Hosmer-Lemeshow检验结果提示模型校准良好(χ^(2)=7.979,P>0.05),DCA显示其临床实用性较好。结论 本研究构建的预测模型具有良好的区分度、校准度与临床实用性,可为老年脊柱手术患者POD的风险评估与个体化干预提供参考。 展开更多
关键词 脊柱手术 老年 术后谵妄 列线图 危险因素 预测模型
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免疫吸附治疗类风湿关节炎的安全性和有效性:网状Meta分析和系统评价
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作者 郑银 吴振桦 +3 位作者 张成 阮可馨 刚骁琳 汲泓 《中国组织工程研究》 北大核心 2026年第5期1260-1268,共9页
目的:运用网状Meta分析评估不同免疫吸附柱治疗类风湿关节炎的有效性与安全性,为临床诊治提供循证依据。方法:计算机检索维普、万方、中国知网、PubMed、CBM、CochraneLibrary、Web of Science等数据库,检索公开发表的免疫吸附柱治疗类... 目的:运用网状Meta分析评估不同免疫吸附柱治疗类风湿关节炎的有效性与安全性,为临床诊治提供循证依据。方法:计算机检索维普、万方、中国知网、PubMed、CBM、CochraneLibrary、Web of Science等数据库,检索公开发表的免疫吸附柱治疗类风湿关节炎的研究,检索时限至2024年8月。采用Cochrane 5.4手册对纳入的随机对照试验进行质量评价,采用纽卡斯尔-渥太华量表(NOS)对回顾性队列研究进行质量评价。运用R4.1.1软件进行贝叶斯网状Meta分析。结果:最终纳入13篇研究,总样本量891例,共有4种免疫吸附柱。网状Meta分析结果表明,降低C-反应蛋白前3名排序:HA280型吸附柱+常规西药>PH-350型吸附柱+常规西药>A蛋白吸附柱;降低红细胞沉降率前3名排序:白细胞吸附柱>HA280型吸附柱+常规西药>PH-350型吸附柱+常规西药;降低关节肿胀计数前3名排序:白细胞吸附柱>A蛋白吸附柱+常规西药>PH-350型吸附柱+常规西药;降低关节压痛计数前3名排序:白细胞吸附柱>A蛋白吸附柱+常规西药>PH-350型吸附柱+常规西药;降低患者对疾病活动性评分前3名排序:PH-350型吸附柱+常规西药>白细胞吸附柱>A蛋白吸附柱;降低目测类比评分前3名排序:PH-350型吸附柱+常规西药>A蛋白吸附柱>白细胞吸附柱;降低医师对疾病活动性评分前3名排序:PH-350型吸附柱+常规西药>白细胞吸附柱>常规西药。结论:基于纳入的13篇文献证据表明,在降低C-反应蛋白方面,HA280型吸附柱联合常规西药作为首选;在降低红细胞沉降率、关节肿胀计数、关节压痛计数方面,白细胞吸附柱作为首选;在降低患者对疾病活动性评分、医师对疾病活动性评分及目测类比评分方面,PH-350型吸附柱联合常规西药作为首选,在临床中可根据患者的具体情况合理选择不同的免疫吸附柱。 展开更多
关键词 类风湿关节炎 吸附柱 免疫吸附柱 免疫吸附法 贝叶斯模型 网状Meta分析
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