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Nucleoside diphosphate-linked moiety X-type motif 15 R139C genotypes impact 6-thioguanine nucleotide cut-off levels to predict thiopurine-induced leukopenia in Crohn’s disease patients 被引量:4
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作者 Xia Zhu Kang Chao +7 位作者 Miao Li Wen Xie Hong Zheng Jin-Xin Zhang Pin-Jin Hu Min Huang Xiang Gao Xue-Ding Wang 《World Journal of Gastroenterology》 SCIE CAS 2019年第38期5850-5861,共12页
BACKGROUND Thiopurine-induced leukopenia(TIL)is a life-threatening toxicity and occurs with a high frequency in the Asian population.Although nucleoside diphosphate-linked moiety X-type motif 15(NUDT15)variants signif... BACKGROUND Thiopurine-induced leukopenia(TIL)is a life-threatening toxicity and occurs with a high frequency in the Asian population.Although nucleoside diphosphate-linked moiety X-type motif 15(NUDT15)variants significantly improve the predictive sensitivity of TIL,more than 50%of cases of this toxicity cannot be predicted by this mutation.The potential use of the 6-thioguanine nucleotide(6TGN)level to predict TIL has been explored,but no decisive conclusion has been reached.Can we increase the predictive sensitivity based on 6TGN by subgrouping patients according to their NUDT15 R139C genotypes?AIM To determine the 6TGN cut-off levels after dividing patients into subgroups according to their NUDT15 R139C genotypes.METHODS Patients’clinical and epidemiological characteristics were collected from medical records from July 2014 to February 2017.NUDT15 R139C,thiopurine S methyltransferase,and 6TGN concentrations were measured.RESULTS A total of 411 Crohn’s disease patients were included.TIL was observed in 72 individuals with a median 6TGN level of 323.4 pmol/8×10^8 red blood cells(RBC),which was not different from that of patients without TIL(P=0.071).Then,we compared the 6TGN levels based on NUDT15 R139C.For CC(n=342)and CT(n=65)genotypes,the median 6TGN level in patients with TIL was significantly higher than that in patients without(474.8 vs 306.0 pmol/8×10^8 RBC,P=9.4×10-^5;291.7 vs 217.6 pmol/8×10^8 RBC,P=0.039,respectively).The four TT carriers developed TIL,with a median 6TGN concentration of 135.8 pmol/8×10^8 RBC.The 6TGN cut-off levels were 411.5 and 319.2 pmol/8×108 RBC for the CC and CT groups,respectively.CONCLUSION The predictive sensitivity of TIL based on 6TGN is dramatically increased after subgrouping according to NUDT15 R139C genotypes.Applying 6TGN cut-off levels to adjust thiopurine therapies based on NUDT15 is strongly recommended. 展开更多
关键词 Crohn’s disease Thioguanine NUCLEOTIDE levels NUCLEOSIDE diphosphatelinked MOIETY x-type MOTIF 15 Thiopurine-induced LEUKOPENIA
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EXPERIMENTAL AND SIMULATED COMPRESSIVE PROPERTIES OF WORK-HARDENED X-TYPE LATTICE TRUSS STRUCTURES 被引量:2
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作者 Qiancheng Zhang Tianjian Lu 《Acta Mechanica Solida Sinica》 SCIE EI 2012年第2期111-116,共6页
The expanded metal sheets were folded with 11% work-hardening. These were sub- sequently used with resistance welding to construct X-type lattice truss sandwich panels having a core relative density of 0.17. The sandw... The expanded metal sheets were folded with 11% work-hardening. These were sub- sequently used with resistance welding to construct X-type lattice truss sandwich panels having a core relative density of 0.17. The sandwich panels were tested in uniaxial compression and, for comparison, the method of finite elements was employed to simulate the measured compressive stress-strain curves. The peak compressive strength was 32% higher than that of pyramidal core sandwiches. The enhanced mechanical properties of the work-hardened X-Type lattice structures mainly originate from the contribution of straight struts with low degree of curvature and work hardening, rather than the two-dimensional staggered nodes. 展开更多
关键词 sandwichs work hardening resistance welding x-type core
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Short beam shear properties and failure modes of the wood-based X-type lattice sandwich structure 被引量:1
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作者 Tengteng Zheng Liuxiao Zou Yingcheng Hu 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期877-887,共11页
A wood-based X-type lattice sandwich structure was manufactured by insertion-glue method.The birch was used as core,and Oriented Strand Board was used as panel of the sandwich structure.The short beam shear properties... A wood-based X-type lattice sandwich structure was manufactured by insertion-glue method.The birch was used as core,and Oriented Strand Board was used as panel of the sandwich structure.The short beam shear properties and the failure modes of the wood-based X-type lattice sandwich structure with different core direction(vertical and parallel),unit specification(120 mm×60 mm and 60 mm×60 mm),core size(50 mm and 60 mm),and drilling depth(9 mm and 12 mm)were investigated by a short beam shear test and the establishment of a theoretical model to study the equivalent shear modulus and deflection response of the X-type lattice sandwich structure.Results from the short beam shear test and the theoretical model showed that the failure modes of the wood-based X-type lattice sandwich structure were mainly the wrinkling and crushing of the panels under three-point bending load.The experimental values of deflection response of various type specimens were higher than the theoretical values of them.For the core direction of parallel,the smaller the unit specification is,the shorter the core size is,and the deeper the drilling depth is,the greater the short beam shear properties of the wood-based X-type lattice sandwich structure is. 展开更多
关键词 x-type Lattice sandwich structure Failure modes Short beam shear properties Theoretical model
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Study on the Design Method of the Jack-up's X-Type Cantilever Allowable Load Nephogram 被引量:1
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作者 Yazhou Zhu Chengmeng Sun +2 位作者 Hongde Qin Bin Jiang Yansong Fan 《Journal of Marine Science and Application》 2014年第3期315-320,共6页
The extending of a cantilever and transverse moving of a drilling floor enable the jack-up to operate in several well positions after the Jack-up has pitched. The cantilever allowable load nephogram is the critical re... The extending of a cantilever and transverse moving of a drilling floor enable the jack-up to operate in several well positions after the Jack-up has pitched. The cantilever allowable load nephogram is the critical reference which can evaluate the jack-up's drilling ability, design the cantilever structure and instruct a jack-up manager to make the operations safe. The intent of this paper is to explore the interrelationships between the cantilever position, drilling floor and the loads including wind force, the stand set-back weight etc., through analyzing the structure and load characteristics of the x-type cantilever and the simplified mechanics model with the restriction of the maximum moment capacity of the cantilever single side beam. Referring to several typical position designs load values, the cantilever allowable load nephogram is obtained by using the suitable interpolation method. The paper gives a method for cantilever allowable load design, which is proved reliable and effective by the calculation example. 展开更多
关键词 JACK-UP cantilever expand cantilever allowable loadnephogram drilling ability x-type cantilever
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捷豹X-TYPE Estate
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作者 晓峰 《汽车与驾驶维修(汽车版)》 2005年第2期18-18,共1页
说起英国的捷豹(Jaguar).似乎有种一言难尽的感觉。当年赫赫有名的英国企业最终也被纳入福特的旗下,英国也就没有了自己独立的汽车品牌。不过.也正是在福特的帮助下.这个英国品牌又得以焕发出勃勃生机。2000年的时候.S-TYPE(也被称... 说起英国的捷豹(Jaguar).似乎有种一言难尽的感觉。当年赫赫有名的英国企业最终也被纳入福特的旗下,英国也就没有了自己独立的汽车品牌。不过.也正是在福特的帮助下.这个英国品牌又得以焕发出勃勃生机。2000年的时候.S-TYPE(也被称为X200)系列的推出使得捷豹的价格能够为更多的消费者所接收.而更容易为人接收的X-TYPE则为捷豹带来了更多的希望——虽然不少保守的英国人认为捷豹这个品牌成为平民车型有损其贵族血统。 展开更多
关键词 捷豹汽车 x-type ESTATE 行李舱 技术性能 汽车外形
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NONLINEAR OPTICAL PROPERTIES OF X-TYPE CHROMOPHORES AND THEIR DOPED FILMS
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作者 叶成 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第5期453-457,共5页
Two X-type chromophores, 2-[4-(4,5-di(4-nitrophenyl) imidazolyl) phenyl]-4,5-di(4-methoxyphenyl)-imidazole (DNPIPDMOPI), 2-[4-(4,5-di(4-nitrophenyl)-imidazolyl) phenyl]-4,5-di(4-aminophenyl)-imidazole (DNPIPDAPI), wer... Two X-type chromophores, 2-[4-(4,5-di(4-nitrophenyl) imidazolyl) phenyl]-4,5-di(4-methoxyphenyl)-imidazole (DNPIPDMOPI), 2-[4-(4,5-di(4-nitrophenyl)-imidazolyl) phenyl]-4,5-di(4-aminophenyl)-imidazole (DNPIPDAPI), were synthesized and characterized. The results show that they possess good nonlinearity, considerable blue-shifted absorption (385 nm and 379 nm in THF) and high decomposition temperature (377 'C and 405 'C). These mean that the X-type chromophores possess a rather good nonlinearity-transparency-thermal stability trade-off. The multi-step corona-poling technique at elevated temperature and in-situ SHG measurements were used to obtain and evaluate the poled films of these chromophores doped in PMMA. The largest SHG signals appeared at 110-120°C, which are 12.5 pm/V and 16.7 pm/V respectively. The dependence of poling induced orientation stability on temperature was measured by depoling experiments and the results indicate that the poling-induced orientation of the films is stable at about 100°C. Theoretic analyses imply that better orientation stability arises from the X-type structure of chromophore. The X-type chromophore has two crossed intramolecular CT, both β xxx and β xyy can contribute to the second-order susceptibility, and the ratio of the tensorial components (γ= β xyy /β xxx ) is about 1/3, so the orientation decay of the films induced by rising temperature will provide a certain compensation for the contribution of β xyy of chromophores. 展开更多
关键词 Nonlinear optical x-type chromophore
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Ultralight X-type lattice sandwich structure(I):Concept,fabrication and experimental characterization 被引量:15
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作者 ZHANG QianCheng HAN YunJie +1 位作者 CHEN ChangQing LU TianJian 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第8期2147-2154,共8页
A new type of ultra-lightweight metallic lattice structure (named as the X-type structure) is reported. This periodic structure was formed by two groups of staggered struts in the traditional pyramid structure, and fa... A new type of ultra-lightweight metallic lattice structure (named as the X-type structure) is reported. This periodic structure was formed by two groups of staggered struts in the traditional pyramid structure, and fabricated by folding expanded metal sheet along rows of offset nodes and then brazing the folded structure (as the core) with top and bottom facesheets to form sandwich panels. The out-of-plane compressive and shear properties of the X-type lattice sandwich structure were investigated experimentally and compared to those of the sandwich having a pyramidal truss core. It is found that the formation of the 2-dimensional staggered nodes can effectively make the X-type structure more resistant to inelastic and plastic buckling under both compression and shear loading than the pyramidal lattice truss. Obtained results show that the compressive and shear peak strengths of the X-type lattice structure are about 30% higher than those of the pyramidal lattice truss having the same relative density. 展开更多
关键词 sandwich panel LATTICE STRUCTURE x-type STRUCTURE BRAZING plastic YIELDING
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梯度磁场与砂率影响下钢纤维水泥基复材的纤维定向规律
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作者 陈卓异 朱校宇 +1 位作者 蔡长丰 李宇 《铁道科学与工程学报》 北大核心 2026年第1期160-170,共11页
传统磁场定向法主要依赖电磁线圈内部匀强磁场,这限制了其在实际工程中的应用。为探讨外部梯度磁场对钢纤维定向的影响,提出一种电磁线圈与E型铁芯组合产生外部梯度磁场制备ASFRC的方法。考虑3种梯度磁场和3类含砂率,制备了36个圆饼形... 传统磁场定向法主要依赖电磁线圈内部匀强磁场,这限制了其在实际工程中的应用。为探讨外部梯度磁场对钢纤维定向的影响,提出一种电磁线圈与E型铁芯组合产生外部梯度磁场制备ASFRC的方法。考虑3种梯度磁场和3类含砂率,制备了36个圆饼形梯度磁场定向试件,借助X-ray扫描结合图像分析技术量化钢纤维方向系数,同时,利用COMSOL软件量化各区域梯度磁场。分析了铁芯对梯度磁场的影响、电流强度对梯度磁场的影响、钢纤维的取向、含砂率对梯度磁场下纤维定向规律的影响、磁场梯度对纤维定向效果的影响等。研究结果表明:COMSOL的模拟结果与实际测量结果一致性高,验证了模拟方法的准确性。E型铁芯的加入显著增强铁芯引导区域的磁感应强度,相较于非引导区域峰值磁感应强度提升122.6%,平均磁感应强度提升95%。随着电流的增加,梯度磁场整体呈现非线性增长的趋势。不同梯度磁场条件下,钢纤维在试件中的定向效果虽有所差异,但与乱向对比均有明显提升,利用梯度磁场可制备方向系数达到0.9及以上的ASFRC。此外,含砂率也是影响钢纤维定向效果的关键因素,含砂率在40%左右时,钢纤维定向效果最佳。研究成果旨在优化定向技术,解决现有磁场定向技术存在的限制,提出适用于实际工程的外部梯度磁场定向设备和工艺。 展开更多
关键词 定向钢纤维水泥基复材 E型铁芯 梯度磁场 X-ray扫描 方向系数
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光谱CT成像联合影像组学在术前预测肾透明细胞癌WHO/ISUP分级的应用
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作者 魏江龙 刘翔 乔英 《放射学实践》 北大核心 2026年第2期188-194,共7页
目的:探讨光谱CT多参数成像联合碘图影像组学在术前预测肾透明细胞癌(ccRCC)WHO/ISUP分级中的应用价值。方法:回顾性分析2019年9月至2024年6月本院130例ccRCC患者,按WHO/ISUP分级分为低级别组(92例)和高级别组(38例),按7:3比例随机分为... 目的:探讨光谱CT多参数成像联合碘图影像组学在术前预测肾透明细胞癌(ccRCC)WHO/ISUP分级中的应用价值。方法:回顾性分析2019年9月至2024年6月本院130例ccRCC患者,按WHO/ISUP分级分为低级别组(92例)和高级别组(38例),按7:3比例随机分为训练集(91例)和验证集(39例)。使用3D-Slicer勾画病灶,计算组内相关系数(ICC),采用LASSO和Logistic回归筛选特征,建立临床、影像组学和联合模型,并通过AUC评估性能,DCA分析其临床实用性。结果:临床模型包含横径、皮髓质期IC、皮髓质期NIC 3个特征,影像组学模型由8个皮髓质期和6个肾造影期特征构成,联合模型为临床特征加影像组学标签构成。在训练集和验证集中,联合模型均具有最优的诊断效能(AUC分别为0.91、0.90)。结论:光谱CT碘图影像组学可有效预测ccRCC病理分级,联合光谱CT参数的模型可进一步提高预测效能,具有潜在临床价值。 展开更多
关键词 肾细胞 体层摄影术 X线计算机 肿瘤病理学类型
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基于sin^(2)x型加速度曲线的桁架式选矸机器人轨迹规划算法研究
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作者 张琛阳 龚范康 +2 位作者 闵振辉 王妍玮 贺延庆 《煤矿机械》 2026年第2期5-13,共9页
针对桁架式选矸机器人在抓矸-置矸作业时,机械臂因高速往复运动产生的冲击与残余振动导致作业效率低、定位精度差的问题,提出一种基于sin^(2)x型加速度曲线的机械臂轨迹规划算法。首先,对选矸机器人机械臂的结构形式进行分析,建立包含... 针对桁架式选矸机器人在抓矸-置矸作业时,机械臂因高速往复运动产生的冲击与残余振动导致作业效率低、定位精度差的问题,提出一种基于sin^(2)x型加速度曲线的机械臂轨迹规划算法。首先,对选矸机器人机械臂的结构形式进行分析,建立包含齿轮齿条啮合特性的机械臂动力学模型,获得轨迹形式对机械臂冲击振动特性的影响机理;其次,针对选矸实际工况,以同步跟踪缓冲抓取为基础,设计基于sin^(2)x型加速度曲线的机械臂轨迹规划算法;最后,结合现有样机开展抓取实验进行算法验证。实验结果表明:相较梯形速度曲线轨迹规划算法,所提出的轨迹规划算法能显著降低机械臂的振动冲击,提升桁架式选矸机器人运动的平稳性,具有较高的工程价值。 展开更多
关键词 机械臂 动力学 轨迹规划 sin^(2)x型加速度曲线
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基于x-type态的量子投票方案
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作者 伍莹 施荣华 《信息与电脑(理论版)》 2010年第9期26-26,共1页
基于x-type纠缠态(四粒子纠缠态),提出一种量子投票方案。方案只使用一组x-type纠缠粒子,与使用N个粒子的投票方案相比,更容易实现。投票者利用复杂性小的相移操作进行投票,提高了方案效率。为了保证投票过程的安全性和防止重复投票,利... 基于x-type纠缠态(四粒子纠缠态),提出一种量子投票方案。方案只使用一组x-type纠缠粒子,与使用N个粒子的投票方案相比,更容易实现。投票者利用复杂性小的相移操作进行投票,提高了方案效率。为了保证投票过程的安全性和防止重复投票,利用纠缠态特性和超密编码设计了检测阶段。在公布测量结果后,决定是否继续本次投票活动。当顺利通过检测后,计票者可使用计分算子计算出投票的结果。在投票过程中,没有单个粒子携带选票内容,整个信息被隐藏在纠缠的粒子间。安全性分析表明,该方案能够防止窃听和篡改选票的干扰。由于方案中制备粒子的简便性、选择候选人的最小复杂性和检测步骤的严密性使得整个方案与其他量子投票方案相比,更高效、实用和安全。 展开更多
关键词 量子移动式投票方案 量子纠缠态 相移操作 x-type
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粉煤灰制备A/X型和X型分子筛及其CO_(2)吸附性能
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作者 徐磊 王虹智 +2 位作者 孙菡蕾 姚硕 刘立成 《低碳化学与化工》 北大核心 2026年第2期117-126,共10页
工业废料资源化利用是可持续发展领域的重要课题,其中粉煤灰的高值化利用尤为重要。以青岛(Q)和淄博(Z)某热电厂两种不同硅铝比(n(Si)/n(Al)分别为2.29和1.42)的粉煤灰为原料,采用碱熔融-水热法合成分子筛用于CO_(2)吸附。采用XRD、XRF... 工业废料资源化利用是可持续发展领域的重要课题,其中粉煤灰的高值化利用尤为重要。以青岛(Q)和淄博(Z)某热电厂两种不同硅铝比(n(Si)/n(Al)分别为2.29和1.42)的粉煤灰为原料,采用碱熔融-水热法合成分子筛用于CO_(2)吸附。采用XRD、XRF和SEM等手段表征了粉煤灰、分子筛的组成及结构特性,并结合单因素实验确定了最优处理及合成条件,研究了碱灰比(质量比)、液固比(质量比)和晶化时间等对合成A/X型和X型分子筛的影响。结果表明,由于粉煤灰硅铝比不同,最优处理及合成条件不同。在碱灰比1.6:1、液固比8:1和晶化6 h的最优条件下,粉煤灰Q合成的X型分子筛比表面积为532.7 m^(2)/g,其动态和静态CO_(2)吸附量分别达到2.77 mmol/g和4.42 mmol/g,显著优于最优条件下粉煤灰Z合成的A/X型分子筛(281.2 m^(2)/g、1.57 mmol/g和3.95 mmol/g)。吸附动力学研究表明,两种分子筛的CO_(2)吸附过程均以物理吸附为主,其中X型分子筛经过10次循环后仍保持了首次吸附时85%以上的CO_(2)吸附量。粉煤灰硅铝比是决定分子筛性能的关键因素,相关结论可为粉煤灰制备高性能分子筛吸附剂提供参考。 展开更多
关键词 粉煤灰 A/X型分子筛 X型分子筛 CO_(2)吸附
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Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts:preparation and catalytic activity
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作者 Qing YE Donghui LI +3 位作者 Jun ZHAO Jiansheng ZHAO Tianfang KANG Shuiyuan CHENG 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2011年第4期497-504,共8页
Au-supported 13X-type zeolite(Au/13X)was synthesized using a common deposition-precipitation(DP)method with a solution of sodium carbonate as a precipitate agent.Further testing was conducted to test for catalytic oxi... Au-supported 13X-type zeolite(Au/13X)was synthesized using a common deposition-precipitation(DP)method with a solution of sodium carbonate as a precipitate agent.Further testing was conducted to test for catalytic oxidation of CO.A study was conducted on the effects of different preparation conditions(i.e.,chloroauric acid concentration,solution temperature,pH of solution,and calcinations temperature)on Au/13X for CO oxidation.In respect to the catalytic activity,the relationship between different the preparation conditions and gold particles in 13X zeolite was analyzed using X-ray diffraction,TEM and XPS.The activity of Au/13X catalysts in CO oxidation was dependent on the chloroauric acid concentration.From XRD results,a higher chloroauric acid concentration induced larger gold nanoparticles,which resulted in lower catalytic activity.Results revealed that higher temperatures induced higher Au loading,homogeneous deposit,and smaller gold clusters on the support of 13X,resulting in higher CO activity.Furthermore,a pH of 5 or 6 generated greater amounts of Au loading and smaller Au particles on 13X than at a pH of 8 or 9.This may be a result of an effective exchange between Au(OH)_(2)Cl_(2)^(-)and Au(OH)_(3)Cl^(-)on specific surface sites of zeolite under the pH’s 5 and 6.The sample calcined at 300℃showed the highest activity,which may be due to the sample’s calcined at 200℃inability to decompose completely to metallic gold while the sample calcined at 400℃had larger particles of gold deposited on the support.It can be concluded from this study that Au/13X prepared from a gold solution with an initial chloroauric acid solution concentration of 1.5×10^(-3)mol·L^(-1)gold solution pH of 6,solution temperature of around 90℃,and a calcination temperature of 300℃provides optimum catalytic activity for CO oxidation. 展开更多
关键词 13x-type zeolite CO oxidation gold solution pH calcination temperature
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第一次Jaguar X-Type Estate
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作者 钟健新 《汽车杂志》 2003年第10期56-57,共2页
捷豹首款官方公布的旅行车X-Type Estate,趁着这个法兰克福车展大集会时推出。在X-Type轿车版推出两年之后,这款体态优美的X—Type旅行车将会在明年春天上市。
关键词 旅行车 法兰克福车展 轿车 捷豹 x-type轿车
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维生素D调节自噬活性和FXR/FGF15信号通路改善大鼠2型糖尿病肾脏功能的作用机制
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作者 赵月萍 刘明 +1 位作者 张奇 张瑞 《川北医学院学报》 2026年第2期129-135,共7页
目的:探究维生素D调节自噬活性和FXR/FGF15信号通路改善大鼠2型糖尿病的作用机制。方法:选取40只SPF级SD大鼠,其中10只大鼠作为对照组,30只构建2型糖尿病模型。将建模成功的27只大鼠分为模型组、维生素D组、维生素D+FXR抑制剂组,每组各... 目的:探究维生素D调节自噬活性和FXR/FGF15信号通路改善大鼠2型糖尿病的作用机制。方法:选取40只SPF级SD大鼠,其中10只大鼠作为对照组,30只构建2型糖尿病模型。将建模成功的27只大鼠分为模型组、维生素D组、维生素D+FXR抑制剂组,每组各9只。比较各组大鼠肾组织病理组织学变化、空腹血糖、胰岛素、体质量、肾功能、炎症因子水平、自噬相关蛋白、FXR/FGF15通路mRNA及蛋白表达水平。结果:对照组大鼠肾组织结构正常;模型组大鼠肾小球肥大、系膜细胞增生,肾小管上皮细胞肿胀变性且部分萎缩;维生素D组大鼠肾病理损伤减轻,而维生素D+FXR抑制剂组大鼠损伤较维生素D组加重,程度介于模型组与维生素D组之间。与对照组相比,模型组大鼠空腹血糖、肌酐(Scr)、尿素氮(BUN)、单核细胞趋化蛋白1(MCP-1)、白细胞介素6(IL-6)、白细胞介素1β(IL-1β)、肿瘤坏死因子ɑ(TNF-ɑ)、P62蛋白表达升高;胰岛素、体质量、溶酶体相关膜蛋白1(LAMP1)、LC3-Ⅱ/Ⅰ蛋白、法尼醇X受体(FXR)、成纤维细胞生长因子15(FGF15)mRNA、蛋白表达水平降低,差异均有统计学意义(P<0.05)。与模型组相比,维生素D组大鼠空腹血糖、Scr、BUN、MCP-1、IL-6、IL-1β、TNF-ɑ、P62蛋白表达降低,胰岛素、体质量、LAMP1、LC3-Ⅱ/Ⅰ蛋白、FXR、FGF15 mRNA、蛋白表达水平升高(P<0.05)。与维生素D组相比,维生素D+FXR抑制剂组大鼠空腹血糖、Scr、BUN、MCP-1、IL-6、IL-1β、TNF-ɑ、P62蛋白表达升高;胰岛素、体质量、LAMP1、LC3-Ⅱ/Ⅰ蛋白、FXR、FGF15 mRNA、蛋白表达水平降低,差异均有统计学意义(P<0.05)。结论:维生素D可改善肾功能,作用机制可能与调节自噬活性和FXR/FGF15通路有关。 展开更多
关键词 2型糖尿病 维生素D 法尼酯X受体/成纤维细胞生长因子 自噬活性 肾脏功能
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宽体矿车X型互联式油气悬架参数匹配方法研究
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作者 李阁强 晏宇泽 +3 位作者 刘雨昌 毛波 王帅 李东林 《机床与液压》 北大核心 2025年第16期180-188,共9页
宽体矿车多行驶于复杂路面,对车辆悬架的振动特性要求较高,目前的同侧互联式和同轴互联式油气悬架无法同时兼备抗俯仰和抗侧倾性能,为此提出X型互联式油气悬架,以提升宽体矿车的抗俯仰和抗侧倾能力。分析X型互联式油气悬架的结构和工作... 宽体矿车多行驶于复杂路面,对车辆悬架的振动特性要求较高,目前的同侧互联式和同轴互联式油气悬架无法同时兼备抗俯仰和抗侧倾性能,为此提出X型互联式油气悬架,以提升宽体矿车的抗俯仰和抗侧倾能力。分析X型互联式油气悬架的结构和工作原理,建立数学模型。分析悬架系统的非线性刚度和非线性阻尼特性以及其参数对性能的影响,并探究悬架的连通特性。最后,利用MATLAB建立整车七自由度模型,将蝗虫优化算法(GOA)应用于油气悬架的参数匹配设计中。结果表明:X型互联式油气悬架具有良好的非线性刚度和非线性阻尼特性,使车辆更平稳地通过复杂路面,且具有抗侧倾和抗俯仰功能,保证车辆在俯仰和侧倾方向的稳定性;采用GOA优化算法对悬架进行参数匹配后,车身的俯仰角加速度、侧倾角加速度、垂直加速度均方根分别降低了32.24%、22.78%、8.86%,提高了车辆的操控稳定性,为X型互联式油气悬架的参数匹配设计提供参考。 展开更多
关键词 X型互联式油气悬架 抗俯仰 抗侧倾 操控稳定性 GOA优化算法
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白术内酯I减轻急性心肌梗死大鼠炎性反应的影响 被引量:1
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作者 曾玉英 姜花 +1 位作者 唐万云 《河北医学》 2025年第2期245-251,共7页
目的:探讨白术内酯I(ATR-I)对急性心肌梗死(AMI)大鼠炎性反应的影响。方法:将大鼠分为假手术组、AMI组、ATR-Ⅰ-L剂量组、ATR-Ⅰ-M剂量组、ATR-Ⅰ-H剂量组和ATR-Ⅰ-H+普乐沙福(AMD3100)干预模型组,每组12只。每天给药1次,持续7d。超声... 目的:探讨白术内酯I(ATR-I)对急性心肌梗死(AMI)大鼠炎性反应的影响。方法:将大鼠分为假手术组、AMI组、ATR-Ⅰ-L剂量组、ATR-Ⅰ-M剂量组、ATR-Ⅰ-H剂量组和ATR-Ⅰ-H+普乐沙福(AMD3100)干预模型组,每组12只。每天给药1次,持续7d。超声影像系统测量大鼠左室短轴缩短率(FS)和射血分数(LVEF);TTC染色检测大鼠心肌梗死面积;HE染色检测大鼠心肌组织病理学;TUNEL染色检测大鼠心肌细胞凋亡;ELISA试剂盒检测大鼠心肌组织中乳酸脱氢酶(LDH)活性、肌红蛋白(MB)、白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)水平;RT-qPCR检测大鼠组织中SDF-1和CXCR4 mRNA的相对表达量;Western blot测定心肌组织中SDF-1和CXCR4蛋白表达。结果:与假手术组相比,AMI组大鼠LVSF和FS、心肌组织中SDF-1、CXCR4 mRNA及其蛋白表达下降(P<0.05),心肌梗死面积、心肌细胞凋亡率和心肌组织中LDH活性、MB、IL-1β和TNF-α水平上升(P<0.05),心肌细胞损伤严重伴有炎性发生;与AMI组相比,ATR-Ⅰ-L组、ATR-Ⅰ-M组和ATR-Ⅰ-H组大鼠LVSF和FS、心肌组织中SDF-1、CXCR4 mRNA及其蛋白表达升高(P<0.05),心肌梗死面积、心肌细胞凋亡率和心肌组织中LDH活性、MB、IL-1β和TNF-α水平降低(P<0.05),心肌细胞损伤有所改善;与ATR-Ⅰ-H组相比,ATR-Ⅰ-H+AMD3100组大鼠LVSF和FS、心肌组织中SDF-1、CXCR4 mRNA及其蛋白表达降低(P<0.05),心肌梗死面积、心肌细胞凋亡率和心肌组织中LDH活性、MB、IL-1β和TNF-α水平上升(P<0.05),心肌细胞损伤加剧。结论:ATR-I减轻AMI大鼠炎性反应。 展开更多
关键词 白术内酯I 基质细胞衍生因子-1 CXC趋化因子受体4 急性心肌梗死 炎性反应
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变指数Kirchhoff方程Neumann问题的非平凡解
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作者 张申贵 《吉林大学学报(理学版)》 北大核心 2025年第6期1549-1556,共8页
用临界点理论中的局部环绕定理和变指数Sobolev空间理论,在不假设(AR)型超线性条件成立时,证明带p(x)-Laplace算子的Kirchhoff型方程非平凡解的存在性.
关键词 Kirchhoff型方程 p(x)-Laplace算子 局部环绕 非平凡解 临界点
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肥胖症合并2型糖尿病的影响因素
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作者 孙鹤 胡天翔 +1 位作者 彭姊鑫 杨奕婧 《中国介入影像与治疗学》 北大核心 2025年第7期472-476,共5页
目的观察肥胖症(Ob)合并2型糖尿病(T2DM)的影响因素。方法回顾性收集20例Ob合并T2DM(A组)及47例单纯Ob(B组),比较组间血糖相关指标[空腹血糖(FBG)、空腹胰岛素(FINS)和糖化血红蛋白(HbA1c)]、稳态模型评估所示胰岛素抵抗指数(HOMA-IR)... 目的观察肥胖症(Ob)合并2型糖尿病(T2DM)的影响因素。方法回顾性收集20例Ob合并T2DM(A组)及47例单纯Ob(B组),比较组间血糖相关指标[空腹血糖(FBG)、空腹胰岛素(FINS)和糖化血红蛋白(HbA1c)]、稳态模型评估所示胰岛素抵抗指数(HOMA-IR)及基于双能量X线吸收测量法、CT或MRI所测脂肪定量参数,分析其相关性,以及Ob合并T2DM的影响因素。结果A组FBG、HbA1c及HOMA-IR高于B组(P均<0.05)。A组全身总脂肪质量百分比(TFM%)及下肢脂肪质量百分比(LFM%)均低于B组,而肝脏及腰椎骨髓质子密度脂肪分数(PDFF)均高于B组(P均<0.05)。全部67例Ob患者TFM%及LFM%均与FBG或HbA1c,TFM%及Android区脂肪质量百分比(Android FM%)均与HOMA-IR呈负相关(r=-0.447~-0.263,P均<0.05),内脏脂肪组织(VAT)面积与HOMA-IR呈正相关(r=0.339,P=0.006),肝脏PDFF与FBG、HbA1c及HOMA-IR,腰椎PDFF与FBG均呈正相关(r=0.323~0.599,P均<0.05)。LFM%升高为Ob合并T2DM的保护因素,而肝脏及胰腺PDFF升高均为其危险因素(P均<0.05)。结论LFM%及肝脏PDFF均为Ob合并T2DM的影响因素。 展开更多
关键词 肥胖症 糖尿病 2型 吸收测定法 光子 体层摄影术 X线计算机 磁共振成像
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大古(DG)水电站戽池尾坎优化试验研究
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作者 杨帆 嘎玛次珠 +2 位作者 张文远 任炜辰 王若兰 《水利与建筑工程学报》 2025年第5期25-30,共6页
大古(DG)水电站建成运行后下游尾水较高而戽池尾坎高度较低,戽池检修时需修建的挡水围堰成本较高且是临时工程。提高戽池尾坎高度兼做检修挡水围堰是方便戽池检修及降低检修成本的有效解决途径。为分析戽式消力池尾坎加高方案的可行性,... 大古(DG)水电站建成运行后下游尾水较高而戽池尾坎高度较低,戽池检修时需修建的挡水围堰成本较高且是临时工程。提高戽池尾坎高度兼做检修挡水围堰是方便戽池检修及降低检修成本的有效解决途径。为分析戽式消力池尾坎加高方案的可行性,通过1∶60的水工模型对DG水电站戽池尾坎加高优化方案的水力特性进行系统研究。研究内容包括对不同戽池尾坎加高体型及高度,戽池内的水流流态、水面线、动水压强分布、流速分布等。试验结果表明:两种尾坎加高体型在相同尾坎加高高程条件下,沿原1∶2坡度加高尾坎方案戽池尾坎处水位壅高幅度相对较低,坎后水面跌落幅度更小,水流条件明显优于尾坎直立加高方案。综合考虑工程造价和兼顾下游电站建成后尾坎既能满足戽池检修挡水的需要又对现有电站的安全运行不造成明显影响等因素影响,确定沿原1∶2坡度将尾坎高程由3360.0m加高尾坎至3369.0 m高程方案是可行的。 展开更多
关键词 DG水电站 戽式消力池 X型宽尾墩 水力特性 模型试验
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