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Preventive effect of Qianggan-Rongxian Decoction on rat liver fibrosis

World Journal of Gastroenterology 2008年第22期14卷 3569-3573页

作者： Chun-Hui Li Li-Hui Pan zong-wei Yang Chun-Yu Li Wen-Xie xu Department of Pathology Affiliated Hospital of Chengde Medical College Chengde 067000 Hebei Province China Chengde Medical College Chengde 067000 Hebei Province China Department of Physiology College of Medicine Shanghai Jiaotong University Shanghai 200030 China

AIM: To study the preventive effects of Qianggan-Rongxian Decoction on liver fibrosis induced by dimethylnitrosamine (DMN) in rats. METHODS: Male Wistar rats were randomly divided into hepatic fibrosis model group, control group and 3 treatment groups (12 rats in each group). Except for the normal control group, all the rats received 1% DMN (10 μL/kg body weight, i.p), 3 times a week for 4 wk. The rats in the 3 treatment groups including a high-dose DMN group (10 mL/kg), a medium-dose DMN group (7 mL/kg), and a low-dose DMN group (4 mL/kg) were daily gavaged with Qianggan-Rongxian Decoction, and the rats in the model and normal control groups were given saline vehicle. Enzyme-linked immunosorbent assay (ELISA) was used to determine the changes in serum hyaluronic acid (HA), laminin (LN), and type IV collagen levels. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured using routine laboratory methods. Pathologic changes, particularly fibrosis, were examined by hematoxylin and eosin (HE) and Sirius red staining. Hepatic stellate cells (HSC) were examined by transmission electron microscopy. RESULTS: Compared with the model control group, the serum levels of HA, LN, type Ⅳ collagen, ALT and AST were decreased markedly in the other groups after treatment with Qianggan-Rongxian Decoction, especially in the medium-dose DMN group (P < 0.05).Moreover, the area-density percentage of collagen fibrosis was lower in the Qianggan-Rongxian Decoction treatment groups than in the model group, and a more significant drop was observed in the medium-dose DMN group (P < 0.05). CONCLUSION: Qianggan-Rongxian Decoction can inhibit hepatic fibrosis due to chronic liver injury, delay the development of cirrhosis, and notably ameliorate liver function. It may be used as a safe and effective thera-peutic drug for patients with fibrosis.

关键词： Liver fibrosis Qianggan-Rongxian Decoction Prevention Rat model Dimethylnitrosamine

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Target-oriented Q-compensated reverse-time migration by using optimized pure-mode wave equation in anisotropic media

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Petroleum Science 2023年第2期20卷 866-878页

作者： Shi-Gang xu Qian-zong Bao Zhi-Ming Ren Chang'an University School of Geological Engineering and GeomaticsDepartment of GeophysicsXi'anShaanxi710064China National Engineering Research Center of Offshore Oil and Gas Exploration Beijing100028China

Research on seismic anisotropy and attenuation plays a significant role in exploration geophysics. To enhance the imaging quality for complicated structures, we develop several effective improvements for anisotropic attenuation effects in reverse-time migration (Q-RTM) on surface and vertical seismic profiling (VSP) acquisition geometries. First, to suppress pseudo-shear wave artifact and numerical instability of the commonly used anisotropic pseudo-acoustic wave equations, an optimized pure P-wave dispersion relation is derived and the corresponding pure-mode wave equation is solved by combining the finite-difference and Possion methods. Second, a simplified anisotropic pure-mode visco-acoustic wave equation (PVAWE) based on standard linear solid model is established. Third, a time-dispersion correlation strategy is applied to improve the modeling accuracy. Fourth, we extend a target-oriented scheme to anisotropic attenuated modeling and imaging. Instead of the conventional wavefield modeling and RTM, the proposed approach can extract available wavefield information near the target regions and produce high imaging resolution for target structures. Last, both anisotropic surface and VSP Q-RTMs are executed by combining optimized PVAWE, time-dispersion correlation and target-oriented algorithm. Modeling examples demonstrate the advantages of our schemes. Moreover, our modified Q-compensated imaging workflow can be regarded as a supplement to the classical anisotropic RTM.

关键词： Anisotropy Attenuation Reverse-time migration Wave equation Optimized algorithm Target-oriented

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The effect of prophylactic antibiotics in acute upper gastrointestinal bleeding patients in the emergency department

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World Journal of Emergency Medicine 2023年第6期14卷 442-447页

作者： Miao Gan Liang zong xuezhong Yu Jun xu Emergency Department State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China

BACKGROUND: Currently, prophylactic antibiotics are recommended only for cirrhotic patients with acute upper gastrointestinal bleeding(AUGIB);however, the benefit for other AUGIB patients remains undetermined. We aimed to compare the clinical outcomes between patients with AUGIB with and without prophylactic antibiotics to identify the population that requires this ***: Patients with AUGIB admitted between 1st January 2019 and 31st December 2021 in the Emergency Department of Peking Union Medical College Hospital were enrolled. Patients were divided into the antibiotic and non-antibiotic groups. The primary outcome was in-hospital mortality, and the secondary outcome was the onset of new infection. The risk factors for mortality and infection were analyzed, and stratification analysis of prophylactic antibiotics was performed. Continuous data were analyzed using the t-test or nonparametric rank sum test, and categorical data were analyzed using the Chi-square test or Fisher's exact test. Indicators with significant differences between the groups were included for logistic regression analysis. A P-value <0.05 was considered statistically significant. RESULTS: A total of 392 individuals were included, among them, 281 patients received prophylactic antibiotics, and 111 patients did not receive prophylactic antibiotics. The mortality rates were significantly lower in the antibiotic group than in the non-antibiotics group(6.41% vs. 17.12%, P=0.001). The risk factors for infection were varicose veins(P=0.045) and endotracheal intubation(P=0.005) in the prophylactic antibiotic group, and endoscopic treatment(P=0.010) in the non-prophylactic antibiotic group. Stratified analyses showed that patients with age ≥ 65 years, endotracheal intubation, endoscopic treatment, and AUGIB of variceal etiologies benefited from prophylactic ***: AUGIB patients may benefit from prophylactic antibiotics to decrease mortality, especially those aged ≥ 65 years a

关键词： Acute upper gastrointestinal bleeding Prophylactic antibiotics Stratification

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Light weight design and integrated method for manufacturing hydraulic wheel-legged robots

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第9期25卷 701-715页

作者： xu LI Haoyang YU Huaizhi zong Haibo FENG Yili FU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China

Design and manufacturing play pivotal roles in hydraulic-driven robotic ***,previous studies have emphasized mainly results and performance,often overlooking the specifics of the design and manufacturing *** paper introduces a novel approach known as light weight design and integrated manufacturing(LD&IM)for hydraulic wheel-legged *** LD&IM method leverages topology optimization and generative design techniques to achieve a substantial 45%weight reduction,enhancing the robot’s dynamic motion *** innovative design method not only streamlines the design process but also upholds the crucial attributes of light weight construction and high strength essential for hydraulic wheel-legged ***,the integrated manufacturing method,incorporating selective laser melting(SLM)and high-precision subtractive manufacturing(SM)processes,expedites the fabrication of high-quality *** the LD&IM approach,a hydraulic-driven single wheel-legged robot,denoted as WLR-IV,has been successfully *** robot boasts low mass and inertia,high strength,and a simplified component *** assess its dynamic jumping capabilities,the control loop integrates a linear quadratic regulator(LQR)and zero dynamic-based controller,while trajectory planning uses the spring-loaded inverted pendulum(SLIP)*** jumping results confirm the WLR-IV single-legged robot’s exceptional dynamic performance,validating both the effectiveness of the LD&IM method and the rationale behind the control strategy.

关键词： Wheel-legged robot Hydraulic driven Topology optimization Wheel-legged robot Hydraulic driven Topology optimization Additive manufacturing(AM) Jump control

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Kerr-NUT-de Sitter Metric and Step-by-step Extension Method

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Chinese Physics Letters 1997年第12期14卷 885-888页

作者： xu Dian-yan QIU zong-yan Department of Computer Science and Technology Peking UniversityBeijing 100871 Department of Information Science School of Mathematical SciencesPeking UniversityBeijing 100871

The Kerr-NUT-de sitter metric in quasi-Boyer-Lindquest coordinate is derived by using the step-by-step extension *** extension may be realized in several different *** example,one of these paths may be chosen as from Schwarzschild-NUT metric to Schwarzschild-NUT-de Sitter metric and from Schwarzschild-NUT-de Sitter metric to Kerr-NUT-de Sitter metric.

关键词： Schwarzschild Sitter Extension

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Mass Loss from Glaciers in the Chinese Altai Mountains between 1959 and 2008 Revealed Based on Historical Maps, SRTM, and ASTER Images

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Journal of Mountain Science 2015年第2期12卷 330-343页

作者： wei Jun-feng LIU Shi-yin xu Jun-li GUO Wan-qin BAO wei-jia SHANGGUAN Dong-hui JIANG zong-li State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences University of Chinese Academy of Sciences Department of Geography University of Zürich Hunan Province Key Laboratory of Coal Resources Clean-Utilization and Mine Environment Protection Hunan University of Science and Technology

Mass loss of glaciers in the Chinese Altai was detected using geodetic methods based on topographical maps(1959), the Shuttle Radar Topography Mission(SRTM) Digital Elevation Model(DEM)(2000), and the Advanced Space-borne Thermal Emission and Reflection Radiometer(ASTER) stereo images(2008). The results indicate that a continued and accelerating shrinkage has occurred in the Chinese Altai Mountains during the last 50 years, with mass deficits of 0.43 ± 0.02 and0.54 ± 0.13 m a-1 water equivalent(w.e.) during the periods 1959-1999 and 1999-2008, ***, the Chinese Altai Mountains have lost 7.06 ±0.44 km3 in ice volume(equivalent to-0.43 ± 0.03 m a-1 w.e.) from 1959-2008. The spatial heterogeneity in mass loss was potentially affected by comprehensive changes in temperature and precipitation, and had a substantial correlation withglacier size and topographic settings. Comparison shows that in the Chinese Altai Mountains glaciers have experienced a more rapid mass loss than those in the Tianshan and northwestern Tibetan Plateau(TP), and the mass balance of glaciers was slightly less negative relative to those in the Russian Altai, Himalaya, and southern TP.

关键词： Altai Mountains Geodetic method Glacier change Mass balance

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Separation and purification of Yb_(2)O_(3) by ion exchange chromatography and preparation of ultra-high purity Yb_(2)O_(3)

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Rare Metals 2023年第8期42卷 2725-2735页

作者： Xi-Juan Pan Zhi-Qing Yang Yang xu Meng Wang Xiao-wei Huang zong-Yu Feng Qiang Zhong Xin-Lin Peng National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing 100088China GRIREM HI-TECH Co. Ltd.Langfang 065201China GRIREM Advanced Materials Co. Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China

Ultra-high purity Yb_(2)O_(3) is the critical material of many high-tech materials such as laser glass and fiber,in which impurities seriously affect the laser color quality,intensity and *** order to reduce the influence of impurities on the properties of laser materials,the purification process of Yb_(2)O_(3) was studied by comparing two kinds of resins(RT-1 and RS-1)using improved ion-exchange chromatography(IEC)*** this study,through the synergistic improvement of resin structure and eluting system,the environmental pollution caused by ammonia water in the traditional IEC method was reduced,and the requirements of high temperature and pressure were *** ion exchange behavior and impurity removal mechanism in the resin column during the loading and eluting process were compared and *** experimental results show that RS-1 resin is all superior to RT-1resin in elements selectivity,ion exchange capacity and impurities removal *** separation and purification by IEC with RS-1 resin,the total removal rate of rare earth impurities was 77.59%and that of non-rare earth impurities was 95.86%when Yb recovery was more than 70%,both higher than that of RT-1 resin(73.26%and 83.18%).This indicates that the improved IEC method is very effective in separating and removing different metal impurities from Yb_(2)O_(3).The pilot test results of IEC method separating and purifying Yb_(2)O_(3) with RS-1 resin show that the purity of Yb_(2)O_(3) can be increased from 99.9929%to 99.9997%by IEC *** has exhibited huge potential of preparing ultra-high purity Yb_(2)O_(3),especially the deep removal of non-rare earth impurities.

关键词： Ultra-high purity Yb_(2)O_(3) Ion exchange chromatography(IEC) Laser fiber Separation mechanism Impurities

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Recent Advances in Fibrous Materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo xu Xiao Feng Xing Yang Zheheng Song Yuhang Song Jingyu Chen Yingcun Liu Chong Gao Yong Du Zhe Sun weilin xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

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机器学习预测肱骨近端骨折钢板内固定后继发性螺钉切出的风险

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中国组织工程研究 2025年第15期29卷 3179-3187页

作者：徐大星涂泽松纪木强许伟鹏牛维广州中医药大学广东省广州市510006 佛山市中医院三水医院骨科广东省佛山市528100 佛山市中医院骨科广东省佛山市528000 广东省中医院关节外科广东省广州市510120

背景:继发性螺钉切出关节面是肱骨近端骨折锁定钢板内固定术后的主要并发症之一,切出的螺钉会磨损关节盂和引起肩峰撞击,影响肩关节功能。因此,准确的风险预测有积极的临床意义。目的:通过机器学习方法筛选肱骨近端骨折钢板内固定后继... 详细信息

背景:继发性螺钉切出关节面是肱骨近端骨折锁定钢板内固定术后的主要并发症之一,切出的螺钉会磨损关节盂和引起肩峰撞击,影响肩关节功能。因此,准确的风险预测有积极的临床意义。目的:通过机器学习方法筛选肱骨近端骨折钢板内固定后继发性螺钉切出的风险因素,开发并验证风险预测模型,便于临床医生早期甄别并干预高风险患者。方法:收集2013年6月至2022年6月接受锁定钢板内固定治疗的214例肱骨近端骨折患者的临床资料作为训练组建立模型,将同一时间段另一医院收治的同类患者61例纳入外部验证组。按照患者术后是否出现继发性螺钉切出,分为螺钉切出组和螺钉维持组。训练组利用随机森林、支持向量机、逻辑回归3种机器学习算法构建预测模型;采用递归特征消除法、10折交叉验证重抽样作为变量的筛选方法,并将3种模型准确度最高时纳入变量的交集作为与螺钉切出高度相关的可靠风险变量。通过R语言软件构建动态预测模型,以网页计算器形式展示,并对模型进行内、外部验证。模型内部检验采用Bootstrap法重抽样1000次,使用受试者工作特征曲线下面积、校准曲线、临床决策曲线评价模型的区分度、校准能力及临床应用价值。通过Youden指数确定预测模型的最佳风险分界值,据此将外部验证组患者分为高、低风险组,根据模型风险预测能力的准确度来评价其稳定性和外延性。结果与结论:①机器学习算法筛选出继发性螺钉切出高度相关的4个风险变量,分别为肱骨近端内侧柱皮质支撑、三角肌结节指数、骨折类型及术后复位情况;②构建的风险预测模型表现出良好的区分度和准确度[曲线下面积=0.874,95%置信区间(0.827,0.922)],校准曲线显示模型预测风险和实际发生风险有较好的一致性;③临床决策曲线提示风险阈值概率在0.1-0.75范围内时,模型具有较好的临床适用性;④风险概率为26%是模型风险分层的最佳阈值,外部验证组利用模型风险分层预测螺钉切出的总正确率为84%;⑤结果说明该风险预测模型准确度和外延性较好,可为指导临床治疗提供依据。

关键词：肱骨近端骨折继发性螺钉切出机器学习影响因素风险预测模型

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Panel data models with cross-sectional dependence: a selective review

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Applied Mathematics(A Journal of Chinese Universities) 2016年第2期31卷 127-147页

作者： xu Qiu-hua CAI zong-wu FANG Ying The Wang Yanan Institute for Studies in Economics MOE Key Laboratory of Econometrics (Xiamen University)Fujian Provincial Key Laboratory of Statistical ScienceXiamen University Department of Economics University of Kansas

In this review, we highlight some recent methodological and theoretical develop- ments in estimation and testing of large panel data models with cross-sectional dependence. The paper begins with a discussion of issues of cross-sectional dependence, and introduces the concepts of weak and strong cross-sectional dependence. Then, the main attention is primarily paid to spatial and factor approaches for modeling cross-sectional dependence for both linear and nonlinear （nonparametric and semiparametric） panel data models. Finally, we conclude with some speculations on future research directions.

关键词： Panel data models Cross-sectional dependence Spatial dependence Interactive fixed effects,Common factors.

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