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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:3
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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:16
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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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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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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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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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糖尿病足患者血清Gal-3、CXCR4及感染相关指标与介入治疗预后关系
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作者 邹子博 陈卓 田野 《北华大学学报(自然科学版)》 2025年第4期500-505,共6页
目的探讨糖尿病足患者血清半乳糖凝集素-3(Gal-3)、趋化因子受体4(CXCR4)及感染相关指标与介入治疗预后的关系。方法选取糖尿病足患者74例(糖尿病足组),均接受介入治疗;同期健康志愿者37名为对照组。酶联免疫吸附法检测血清Gal-3、CXCR... 目的探讨糖尿病足患者血清半乳糖凝集素-3(Gal-3)、趋化因子受体4(CXCR4)及感染相关指标与介入治疗预后的关系。方法选取糖尿病足患者74例(糖尿病足组),均接受介入治疗;同期健康志愿者37名为对照组。酶联免疫吸附法检测血清Gal-3、CXCR4及降钙素原水平;全自动血细胞分析仪进行血常规检测,记录白细胞计数;免疫比浊法检测血清C反应蛋白水平。介入治疗后6个月,通过数字减影血管造影评价疗效,分为再狭窄组和非狭窄组。结果糖尿病足组患者血清Gal-3、白细胞计数、C反应蛋白、降钙素原水平高于对照组,血清CXCR4水平低于对照组(均P<0.05)。血清Gal-3、CXCR4及白细胞计数、C反应蛋白、降钙素原在不同Wagner分级的糖尿病足患者间比较差异具有统计学意义(P<0.05),随着Wagner分级的升高,血清Gal-3、白细胞计数、C反应蛋白、降钙素原水平逐渐升高,CXCR4水平逐渐降低。再狭窄组糖尿病足患者血清Gal-3、白细胞计数、C反应蛋白、降钙素原水平高于非狭窄组,血清CXCR4水平低于非狭窄组(P<0.05)。多因素Cox比例风险回归模型分析显示,血清Gal-3、CXCR4及白细胞计数、C反应蛋白、降钙素原表达水平是糖尿病足患者介入预后的独立影响因素。ROC曲线分析显示,血清Gal-3、CXCR4、白细胞计数、C反应蛋白、降钙素原截断值为6.48 ng/mL、2.26 ng/mL、9.93×10^(9)/L、13.05 mg/L、1.17μg/L时对糖尿病足患者介入治疗预后的预测价值依次为血清Gal-3(AUC=0.835)、CXCR4(AUC=0.869)及白细胞计数(AUC=0.751)、C反应蛋白(AUC=0.807)、降钙素原(AUC=0.782),各指标预测糖尿病足患者介入治疗预后AUC均>0.700,有一定的预测价值,且联合预测价值(AUC=0.964)高于血清Gal-3、CXCR4及白细胞计数、C反应蛋白、降钙素原单独预测(Z=2.581、2.204、3.761、3.027,P=0.021、0.024、0.011、0.016)。结论糖尿病足患者血清Gal-3、白细胞计数、C反应蛋白、降钙素原高表达,血清CXCR4低表达,且与病情严重程度和预后有关,联用对介入治疗的预后具有较高预测价值。 展开更多
关键词 糖尿病足 介入治疗 预后 半乳糖凝集素-3 趋化因子受体4 感染相关指标
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过冷水中蒸汽射流自旋凝结的实验研究
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作者 丛红钏 韩沛东 +2 位作者 周子棋 孙中国 席光 《西安交通大学学报》 北大核心 2025年第2期23-31,共9页
针对蒸汽射流自旋凝结过程中的复杂流动和相变展开实验研究,采用新型X型旋流压力喷嘴实现了蒸汽射流的自旋流动,分析了不同流量下旋转气泡的冷凝模式以及相关参数的演化规律,包括气泡半径、生长速率、溃灭速率、气泡质心最大迁移速度和... 针对蒸汽射流自旋凝结过程中的复杂流动和相变展开实验研究,采用新型X型旋流压力喷嘴实现了蒸汽射流的自旋流动,分析了不同流量下旋转气泡的冷凝模式以及相关参数的演化规律,包括气泡半径、生长速率、溃灭速率、气泡质心最大迁移速度和溃灭频率。结果表明:蒸汽射流自旋凝结可划分为光滑生长气泡机制、过渡气泡机制和粗糙生长气泡机制。在离心力作用下,凝结过程中可能出现颈部螺旋发展和气泡顶部凸起不规则变形等典型行为。随着质量流量的增加,气泡冷凝时间缩短,生长速率有所增加,气泡半径和溃灭速率呈现非线性变化,气泡质心最大迁移速度范围为24.3~73.23 m/s,气泡溃灭频率为20~302 Hz。同一质量流量下,气泡可能在不同方向上发生冷凝并出现之字形运动轨迹。气泡质心偏离喷嘴中心轴线角度增大,有助于减小气泡溃灭过程中发生回弹的次数,对气泡生长速率、溃灭速率和气泡质心最大迁移速度产生非线性影响。研究结果可为开发和优化相关工业领域中的冷凝技术提供重要的理论依据。 展开更多
关键词 旋转蒸汽射流 X型旋流压力喷嘴 气泡凝结特性
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基于增强CT术前诊断增殖型肝细胞癌的临床价值及预后分析 被引量:1
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作者 成杰 魏晓凡 +2 位作者 陈伟 叶小龙 张维 《陆军军医大学学报》 北大核心 2025年第7期708-719,共12页
目的基于增强CT影像特征构建增殖型肝细胞癌(hepatocellular carcinoma,HCC)的术前预测模型并进行预后分析。方法采用回顾性病例-对照研究方法。共纳入经病理证实为HCC的患者603例;其中陆军军医大学第一附属医院519例,以7︰3的比例随机... 目的基于增强CT影像特征构建增殖型肝细胞癌(hepatocellular carcinoma,HCC)的术前预测模型并进行预后分析。方法采用回顾性病例-对照研究方法。共纳入经病理证实为HCC的患者603例;其中陆军军医大学第一附属医院519例,以7︰3的比例随机分为训练组(n=363)和内部验证组(n=156);将重庆医科大学附属第二医院84例患者作为外部验证组。患者术前均行腹部CT增强检查,观察增殖型与非增殖型HCC患者临床资料情况及CT影像学特征。采用二元Logistic回归分析筛选增殖型HCC的独立危险因素,构建列线图预测模型,通过受试者工作特征曲线(receiver operating characteristic curve,ROC)、ROC曲线下面积(area under curve,AUC)评价其诊断效能,绘制校准曲线、决策曲线(decision curve analysis,DCA)评估列线图模型的校准性能和临床应用价值,并在内部验证组和外部验证组对模型进行验证。使用Kaplan-Meier生存曲线对比增殖型和非增殖型HCC的预后。结果多因素分析结果示乙型肝炎病毒脱氧核糖核酸(hepatitis B virus deoxyribonucleic acid,HBV-DNA)定量阴性、肿瘤包膜不完整、瘤内坏死或缺血(≥20%)、动脉期环形高强化是预测增殖型HCC的独立预测因子(P<0.05)。基于以上临床影像特征绘制预测增殖型HCC的列线图,在训练组AUC为0.805(95%CI:0.756~0.854),敏感度83.19%,特异度64.80%;在内部验证组中,AUC为0.793(95%CI:0.721~0.854),敏感度67.86%,特异度75.00%;在外部验证组中,AUC为0.842(95%CI:0.746~0.912),敏感度72.41%,特异度90.91%;校准曲线、DCA曲线示列线图模型的校准性能和临床适用性均较好。经病理证实/预测模型诊断的增殖型HCC患者术后无病生存期(disease free survival,DFS)均显著低于非增殖型HCC(训练组:P=0.005,P<0.001;内部验证组:P=0.006,P=0.006;外部验证组:P=0.002,P=0.015)。结论基于临床与影像特征构建的预测模型能较准确术前诊断增殖型HCC,且增殖型HCC预后较差。 展开更多
关键词 增殖型 肝细胞癌 X线计算机体层摄影术 预后研究
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基于MXene材料和X型DNA的荧光适配体传感器检测Pb^(2+)和Cd^(2+)
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作者 白天 孙佳一 +3 位作者 贾瑞淑 索志光 卫敏 金华丽 《食品安全质量检测学报》 2025年第15期101-109,共9页
目的基于MXene纳米材料,利用X型DNA和适配体构建了一种新型荧光适配体传感器,用于同时检测食品中的Pb^(2+)和Cd^(2+)。方法利用碱基互补配对制备X型DNA结构,在Pb^(2+)和Cd^(2+)存在的情况下,X型DNA结构中的适配体与目标物特异性结合,并... 目的基于MXene纳米材料,利用X型DNA和适配体构建了一种新型荧光适配体传感器,用于同时检测食品中的Pb^(2+)和Cd^(2+)。方法利用碱基互补配对制备X型DNA结构,在Pb^(2+)和Cd^(2+)存在的情况下,X型DNA结构中的适配体与目标物特异性结合,并触发MXene表面的解吸,从而恢复荧光信号。结果在最佳实验条件下,荧光信号强度与Pb^(2+)和Cd^(2+)在0.5~500.0 nmol/L范围内呈线性相关,检出限分别为0.33 nmol/L和0.28 nmol/L,结果表明该传感器具有良好的工作性能。结论本研究制备的荧光生物传感器已成功应用于自来水和麦片的加标分析,具有良好的回收率,表明可作为检测食品中Pb^(2+)和Cd^(2+)的有效工具。 展开更多
关键词 MXene纳米材料 X型DNA纳米结构 荧光生物传感器 重金属
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新医科背景下复合型医学人才培养模式探索与实践
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作者 唐双凤 杨琦 +5 位作者 曲佳琳 许才明 徐兆超 陆瑶 朱慧超 张桂信 《中国医学教育技术》 2025年第6期742-747,共6页
为探索“医+X”交叉学科融合培养模式,提出复合型医学人才培养新范式。基于“宽基础、融交叉、强科研、重应用”理念,以培养兼具临床技能与科研创新能力的复合型医学人才为目标,通过构建“五化协同”培养体系(强化培养模式、优化课程建... 为探索“医+X”交叉学科融合培养模式,提出复合型医学人才培养新范式。基于“宽基础、融交叉、强科研、重应用”理念,以培养兼具临床技能与科研创新能力的复合型医学人才为目标,通过构建“五化协同”培养体系(强化培养模式、优化课程建设、深化资源配置、细化导师制度、实化平台融合),突破传统学科壁垒,同时采用理论与实践相结合的方法,重点建立“临床需求导向—交叉思维训练—创新能力提升”三位一体培养路径,形成跨越学科边界的深度互动机制。研究结果表明,该模式通过系统整合医学与多学科资源,有效提升学生临床实践能力和科研创新能力,为高校医学教育改革提供了可复制的范式参考。 展开更多
关键词 “医+X” 交叉学科 复合型 创新人才
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