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腹腔镜胆总管探查一期缝合术适应证及胆漏防治4100例临床经验
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作者 张光全 郑柳 +2 位作者 谢亮 姚波 侯金平 《四川医学》 CAS 2024年第7期776-779,共4页
目的探讨腹腔镜胆总管探查(LCBDE)一期缝合适应证及胆漏并发症防治技术。方法回顾性分析2000年1月至2023年8月我院收治的4100例胆囊结石合并胆总管结石行LCBDE一期缝合术患者的临床资料,包括病例纳入标准、技术方法及胆漏并发症的防治... 目的探讨腹腔镜胆总管探查(LCBDE)一期缝合适应证及胆漏并发症防治技术。方法回顾性分析2000年1月至2023年8月我院收治的4100例胆囊结石合并胆总管结石行LCBDE一期缝合术患者的临床资料,包括病例纳入标准、技术方法及胆漏并发症的防治经验。结果4100例LCBDE一期缝合术均顺利完成,无中转开腹。术后3991例(97.34%)恢复顺利,109例(2.66%)发生胆漏。其中101例(2.46%)漏胆不伴腹膜炎50~200 ml/d,乳胶管引流1~2周自愈,8例(0.19%)胆漏伴腹膜炎再次手术胆总管置T管及腹腔引流术,本组无死亡病例。结论胆总管结石采用LCBDE一期缝合术的方法是安全有效而且有优势的选择术式。 展开更多
关键词 腹腔镜胆总管探查 适应证 一期缝合 胆漏
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胰岛素样生长因子1对人RPE细胞分泌TGF-β2、MMP-2的影响及机制研究 被引量:1
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作者 晁荣荣 郑柳 +1 位作者 范晶 丁芝祥 《眼科新进展》 CAS 北大核心 2024年第7期512-517,共6页
目的研究胰岛素样生长因子1(IGF-1)对人视网膜色素上皮细胞(ARPE-19)表达转化生长因子β2(TGF-β2)、基质金属蛋白酶2(MMP-2)的影响,并探索其作用机制。方法ARPE-19细胞分别按不同浓度IGF-1和不同浓度LY294002培养6 h、12 h、24 h、48 h... 目的研究胰岛素样生长因子1(IGF-1)对人视网膜色素上皮细胞(ARPE-19)表达转化生长因子β2(TGF-β2)、基质金属蛋白酶2(MMP-2)的影响,并探索其作用机制。方法ARPE-19细胞分别按不同浓度IGF-1和不同浓度LY294002培养6 h、12 h、24 h、48 h,采用CCK-8法检测细胞活力,确定IGF-1、LY294002的最佳作用浓度与时间。细胞划痕法检测细胞迁移活性。ELISA法检测细胞培养上清液中TGF-β2浓度。将ARPE-19细胞分为对照组、IGF-1组(80μg·L^(-1) IGF-1)、IGF-1+LY294002组(80μg·L^(-1) IGF-1+30 mmol·L^(-1) LY294002)、LY294002组(30 mmol·L^(-1) LY294002),使用无血清DMEM/F12培养基培养,对照组不做任何处理,分别采用RT-PCR、Western blot检测细胞中TGF-β2、MMP-2、磷脂酰肌醇-3-激酶(PI3K)、蛋白激酶B(AKT)的mRNA和蛋白表达量。结果与0μg·L^(-1) IGF-1比较,80μg·L^(-1) IGF-1的细胞活力24 h变化显著(P<0.05),故确定其为IGF-1最佳作用浓度和时间。与0 mmol·L^(-1) LY294002比较,24 h的30 mmol·L^(-1) LY294002接近半数抑制浓度,故确定其为LY294002最佳作用时间和浓度。细胞划痕法检测结果显示,0μg·L^(-1) IGF-1组、40μg·L^(-1) IGF-1组、80μg·L^(-1) IGF-1组细胞迁移率整体比较及两两比较差异均有统计学意义(均为P<0.05)。ELISA检测结果显示,0μg·L^(-1) IGF-1组、40μg·L^(-1) IGF-1组、80μg·L^(-1) IGF-1组细胞上清液中TGF-β2浓度整体比较及两两比较差异均有统计学意义(均为P<0.05)。RT-PCR、Western blot检测结果显示,IGF-1、LY294002培养24 h,与对照组比较,IGF-1组细胞中TGF-β2、MMP-2、PI3K、AKT的mRNA与蛋白表达水平均升高,而LY294002组细胞中TGF-β2、MMP-2、PI3K、AKT的mRNA与蛋白表达水平均下降(均为P<0.05);与IGF-1组比较,IGF-1+LY294002组细胞中TGF-β2、MMP-2、PI3K、AKT的mRNA与蛋白表达水平均下降(均为P<0.05)。结论IGF-1能促进ARPE-19细胞增殖、迁移;IGF-1可能通过PI3K/AKT信号通路上调ARPE-19细胞中TGF-β2、MMP-2的表达,参与近视的发生与发展。 展开更多
关键词 近视 视网膜色素上皮细胞 胰岛素样生长因子1 磷脂酰肌醇-3-激酶/蛋白激酶B通路 转化生长因子Β2 基质金属蛋白酶2
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选区激光熔化Ti-6Al-4V合金在模拟乏燃料后处理环境中的腐蚀行为
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作者 刘政 张连民 +3 位作者 任德春 马爱利 吉海宾 郑玉贵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第7期2167-2180,共14页
研究选区激光熔化(SLM)制备的Ti-6Al-4V合金在乏燃料后处理环境中的腐蚀行为。借助光学显微镜、X射线衍射、扫描电子显微镜、电子背散射衍射以及电化学测试等手段研究SLMTi-6Al-4V合金的显微组织及耐蚀性。结果表明,相较于铸造合金,SLM ... 研究选区激光熔化(SLM)制备的Ti-6Al-4V合金在乏燃料后处理环境中的腐蚀行为。借助光学显微镜、X射线衍射、扫描电子显微镜、电子背散射衍射以及电化学测试等手段研究SLMTi-6Al-4V合金的显微组织及耐蚀性。结果表明,相较于铸造合金,SLM Ti-6Al-4V合金在含氧化性离子的6 mol/L热硝酸溶液中的耐腐蚀性更好。进一步分析表明,SLMTi-6Al-4V合金具有α'+β的微观结构,β-Ti相含量较高且分布均匀,同时其晶粒尺寸较小、晶界密度较高,这种微观结构可提高其在含氧化性离子的硝酸中的钝化能力以及耐腐蚀性。SLM Ti-6Al-4V合金有望在乏燃料后处理过程中得到广泛应用。 展开更多
关键词 乏燃料后处理 选区激光熔化 TI-6AL-4V合金 腐蚀行为 钝化性能
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血清FKN、Copeptin与新生儿感染性肺炎患儿免疫功能与病情的关系
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作者 李烨 刘婷 +3 位作者 郑柳 李丽 王芊 徐征 《标记免疫分析与临床》 CAS 2024年第9期1661-1665,共5页
目的探讨分析血清不规则趋化因子(FKN)、和肽素(Copeptin)与新生儿感染性肺炎患儿免疫功能与病情的关系。方法纳入2021年10月至2023年10月我院诊治的新生儿感染性肺炎患儿82例,设为观察组,并纳入同期分娩的80例健康新生儿,作为对照组。... 目的探讨分析血清不规则趋化因子(FKN)、和肽素(Copeptin)与新生儿感染性肺炎患儿免疫功能与病情的关系。方法纳入2021年10月至2023年10月我院诊治的新生儿感染性肺炎患儿82例,设为观察组,并纳入同期分娩的80例健康新生儿,作为对照组。入组新生儿均于入院时取其血清样本,采用贝克曼全自动特定蛋白免疫分析仪IMMAGE800检测其血清免疫球蛋白水平,采用酶联免疫吸附法检测血清炎症因子水平以及血清FKN、Copeptin水平,然后采用Spearman相关系数分析水平与患儿免疫功能与病情的关系。结果观察组患儿血清FKN、Copeptin和血清免疫球蛋白A(IgA)、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、C反应蛋白(CRP)、白细胞介素10(IL-10)、降钙素原(PCT)、白细胞介素17(IL-17)水平高于对照组(P<0.05)。重症患儿血清FKN、Copeptin和血清IgM、IgA、IgG、CRP、IL-10、PCT、IL-17水平高于轻症患儿(P<0.05)。Spearman相关性分析结果显示,血清FKN、Copeptin水平与IgM、IgA、IgG、CRP、PCT、IL-10、IL-17水平呈正相关关系(P<0.05)。结论新生儿感染性肺炎患儿血清FKN、Copeptin水平较高,其水平与患儿免疫功能和病情严重程度呈正相关关系,监测其水平对早期评估患儿病情及免疫功能具有重要参考意义,进而指导临床治疗,提高患儿生命质量。 展开更多
关键词 新生儿感染性肺炎 免疫功能 病情 不规则趋化因子 和肽素
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二甲双胍对转化生长因子-β_(2)(TGF-β_(2))诱导的人晶状体上皮细胞增殖、迁移及上皮间质转化的影响
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作者 张昀昀 郑柳 +2 位作者 王舒 杨彬彬 丁芝祥 《眼科新进展》 CAS 北大核心 2024年第9期692-696,共5页
目的研究二甲双胍对转化生长因子-β_(2)(TGF-β_(2))诱导的人晶状体上皮细胞(LEC)增殖、迁移及上皮间质转化的影响。方法选择永生化人LEC(HLEB-3细胞)作为细胞来源;将细胞融合度80%的人LEC置于含10 mg·L^(-1)TGF-β_(2)的DMEM低... 目的研究二甲双胍对转化生长因子-β_(2)(TGF-β_(2))诱导的人晶状体上皮细胞(LEC)增殖、迁移及上皮间质转化的影响。方法选择永生化人LEC(HLEB-3细胞)作为细胞来源;将细胞融合度80%的人LEC置于含10 mg·L^(-1)TGF-β_(2)的DMEM低糖培养基中培养24 h作为对照组,经TGF-β_(2)处理再加入不同浓度二甲双胍进一步作用后的细胞作为实验组。处理后在倒置显微镜下观察各组细胞的形态变化。采用CCK-8实验检测细胞毒性,计算细胞存活率,Western blot法检测细胞中辅助激活因子Yes相关蛋白1(YAP1)、大肿瘤抑制因子1(LATS1)、波型蛋白(Vimentin)的表达,实时荧光定量PCR检测YAP1、LATS1、哺乳动物STE20样激酶1(MST1)、Vimentin、E-钙黏蛋白mRNA的表达。结果二甲双胍细胞毒性检测结果显示,当二甲双胍浓度大于15.0 mmol·L^(-1)时,人LEC的存活率明显降低,表明二甲双胍浓度对LEC存活影响较大,因此选择15.0 mmol·L^(-1)进行后续实验。二甲双胍对TGF-β_(2)诱导的人LEC增殖有显著的抑制作用,且呈明显的剂量依赖性(均为P<0.001)。15.0 mmol·L^(-1)二甲双胍作用于人LEC 24 h后细胞中YAP1和Vimentin蛋白相对表达量均低于对照组(均为P<0.05);LATS1蛋白相对表达量高于对照组(P<0.05)。15.0 mmol·L^(-1)二甲双胍作用于人LEC 24 h后细胞中YAP1和Vimentin mRNA相对表达量均低于对照组,LATS1、MST1、E-钙黏蛋白mRNA相对表达量均高于对照组,差异均有统计学意义(均为P<0.05)。结论二甲双胍在体外能够对TGF-β_(2)诱导的人LEC增殖、迁移及上皮间质转化产生抑制作用,同时可下调YAP1和Vimentin mRNA的表达,上调LATS1、MST1、E-钙黏蛋白mRNA的表达;该作用机制可能与其激活Hippo信号通路有关。 展开更多
关键词 二甲双胍 转化生长因子-β_(2) 细胞增殖 细胞迁移 上皮间质转化
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The role of axon guidance molecules in the pathogenesis of epilepsy
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作者 zheng liu Chunhua Pan Hao Huang 《Neural Regeneration Research》 SCIE CAS 2025年第5期1244-1257,共14页
Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target no... Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with the pathogenicity of axon guidance molecules in epilepsy, offering a valuable reference for the exploration of therapeutic targets and presenting a fresh perspective on treatment strategies for this condition. 展开更多
关键词 axon guidance drug-resistant epilepsy EPILEPSY nerve regeneration nervous system diseases neural pathways neuroinflammatory diseases neuronal plasticity NEURONS synaptic remodeling
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An efficient strategy for the preparation of MIL-53(Al)-NH_(2)membranes with high ion selectivity and desalination performance
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作者 Wenmin Li zheng liu +4 位作者 Xingya Li Rongqiang Fu Zhaoming liu Tingting Xu Tongwen Xu 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期41-47,I0010,共8页
The efficient extraction of sodium(Na^(+))and lithium(Li^(+))from seawater and salt lakes is increasingly demanding due to their great application value in chemical industries.However,coexisting cations such as divale... The efficient extraction of sodium(Na^(+))and lithium(Li^(+))from seawater and salt lakes is increasingly demanding due to their great application value in chemical industries.However,coexisting cations such as divalent calcium(Ca^(2+))and magnesium(Mg^(2+))ions are at the subnanometer scale in diameter,similar to target monovalent ions,making ion separation a great challenge.Here,we propose a simple and fast secondary growth method for the preparation of MIL-53(Al)-NH_(2)membranes on the surface of anodic aluminum oxide.Such membranes contain angstrom-scale(~7Å)channels for the entrance of small monovalent ions and water molecules,endowing the selectivities for monovalent cations over divalent cations and water over salt molecules.The resulting high-connectivity MIL-53(Al)-NH_(2)membranes exhibit excellent ion separation performance(a selectivity of 121.42 for Na^(+)/Ca^(2+)and 93.81 for Li^(+)/Mg^(2+))and desalination performance(a water/salt selectivity of up to 5196).This work highlights metal–organic framework membranes as potential candidates for realizing ion separation and desalination in liquid treatment. 展开更多
关键词 metal-organic framework MIL-53(Al)-NH_(2) MEMBRANE ion selectivity DESALINATION
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Quantitative trait loci identification reveals zinc finger protein CONSTANS-LIKE 4 as the key candidate gene of stigma color in watermelon(Citrullus lanatus)
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作者 Shuang Pei Zexu Wu +4 位作者 Ziqiao Ji zheng liu Zicheng Zhu Feishi Luan Shi liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2292-2305,共14页
Stigma color is a critical agronomic trait in watermelon that plays an important role in pollination.However,there are few reports on the regulation of stigma color in watermelon.In this study,a genetic analysis of th... Stigma color is a critical agronomic trait in watermelon that plays an important role in pollination.However,there are few reports on the regulation of stigma color in watermelon.In this study,a genetic analysis of the F2 population derived from ZXG1553(P1,with orange stigma)and W1-17(P2,with yellow stigma)indicated that stigma color is a quantitative trait and the orange stigma is recessive compared with the yellow stigma.Bulk segregant analysis sequencing(BSA-seq)revealed a 3.75 Mb segment on chromosome 6 that is related to stigma color.Also,a major stable effective QTL Clqsc6.1(QTL stigma color)was detected in two years between cleaved amplified polymorphic sequencing(CAPS)markers Chr06_8338913 and Chr06_9344593 spanning a~1.01 Mb interval that harbors 51 annotated genes.Cla97C06G117020(annotated as zinc finger protein CONSTANS-LIKE 4)was identified as the best candidate gene for the stigma color trait through RNA-seq,quantitative real-time PCR(qRT-PCR),and gene structure alignment analysis among the natural watermelon panel.The expression level of Cla97C06G117020 in the orange stigma accession was lower than in the yellow stigma accessions with a significant difference.A nonsynonymous SNP site of the Cla97C06G117020 coding region that causes amino acid variation was related to the stigma color variation among nine watermelon accessions according to their re-sequencing data.Stigma color formation is often related to carotenoids,and we also found that the expression trend of ClCHYB(annotated asβ-carotene hydroxylase)in the carotenoid metabolic pathway was consistent with Cla97C06G117020,and it was expressed in low amounts in the orange stigma accession.These data indicated that Cla97C06G117020 and ClCHYB may interact to form the stigma color.This study provides a theoretical basis for gene fine mapping and mechanisms for the regulation of stigma color in watermelon. 展开更多
关键词 WATERMELON stigma color gene mapping zinc finger protein CONSTANS-LIKE 4
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Magnetic proximity effect in the two-dimensional ε-Fe_(2)O_(3)/NbSe_(2)heterojunction
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作者 车冰玉 胡国静 +17 位作者 朱超 郭辉 吕森浩 刘轩冶 吴康 赵振 潘禄禄 祝轲 齐琦 韩烨超 林晓 李子安 申承民 鲍丽宏 刘政 周家东 杨海涛 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期492-497,共6页
Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie te... Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie temperature and instability in air,it is hard to realize practical applications for the reported layered magnetic materials at present.In this paper,we developed a space-confined chemical vapor deposition method to synthesize ultrathin air-stable ε-Fe_(2)O_(3) nanosheets with Curie temperature above 350 K.The ε-Fe_(2)O_(3)/NbSe_(2) heterojunction was constructed to study the magnetic proximity effect on the superconductivity of the NbSe_(2) multilayer.The electrical transport results show that the subtle proximity effect can modulate the interfacial spin–orbit interaction while undegrading the superconducting critical parameters.Our work paves the way to construct 2D heterojunctions with ultrathin nonlayered materials and layered van der Waals(vdW)materials for exploring new physical phenomena. 展开更多
关键词 two-dimensional heterojunctions magnetic proximity effect non-layered magnetic nanosheet spin-orbit interaction
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Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS
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作者 Jiaqi Hu zheng liu +1 位作者 Zuoliang Ning Hong Gao 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期281-294,共14页
Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tes... Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were conducted.The rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of corrosion.In air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking paths.Compared with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack tip.The corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of specimen.However,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic dissolution.Owing to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS. 展开更多
关键词 Magnesium alloy ORIENTATION CORROSION Fatigue crack growth
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Prospect of Hexagonal CsMg(I_(1-x)Br_(x))_(3) Alloys for Deep-Ultraviolet Light Emission
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作者 Siyuan Xu zheng liu +3 位作者 Xun Xu Su-Huai Wei Yuzheng Guo Xie Zhang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第9期52-56,共5页
Materials for deep-ultraviolet(DUV)light emission are extremely rare,significantly limiting the development of efficient DUV light-emitting diodes.Here we report CsMg(I_(1−x)Br_(x))_(3) alloys as potential DUV light e... Materials for deep-ultraviolet(DUV)light emission are extremely rare,significantly limiting the development of efficient DUV light-emitting diodes.Here we report CsMg(I_(1−x)Br_(x))_(3) alloys as potential DUV light emitters.Based on rigorous first-principles hybrid functional calculations,we find that CsMgI_(3) has an indirect bandgap,while CsMgBr_(3) has a direct bandgap.Further,we employ a band unfolding technique for alloy supercell calculations to investigate the critical Br concentration in CsMg(I_(1−x)Br_(x))_(3) associated with the crossover from an indirect to a direct bandgap,which is found to be∼0.36.Thus,CsMg(I_(1−x)Br_(x))_(3) alloys with 0.366≤6≤1 cover a wide range of direct bandgap(4.38–5.37 eV;284–231 nm),falling well into the DUV regime.Our study will guide the development of efficient DUV light emitters. 展开更多
关键词 ALLOYS alloy Deep
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Detection of Endocrine Disruptors in Water around Landfills
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作者 Dandan liu Qing LI +4 位作者 Yaohong liu Sha FENG Tao MO zheng liu Xiaonan ZOU 《Agricultural Biotechnology》 2024年第1期66-70,73,共6页
[Objectives]This study was conducted to explore the occurrence levels of endocrine disruptors(EDCs)in rural areas around a county landfill in Tongren City.[Methods]The water around the landfill was sampled and analyze... [Objectives]This study was conducted to explore the occurrence levels of endocrine disruptors(EDCs)in rural areas around a county landfill in Tongren City.[Methods]The water around the landfill was sampled and analyzed.A solid-phase extraction and high performance liquid chromatography-tandem mass spectrometry(SPE-UPLC-MS/MS)method was established for the determination of 27 EDCs.After the HLB solid-phase extraction column was activated,a water sample,which was adjusted with phosphoric acid to a pH of 2(±0.5)and added with 500 mg of disodium EDTA,was loaded,and 5 ml of water and 20%methanol water was added for washing.Next,10 ml of elution solution was added for elution,and the collected eluate was evaporated under reduced pressure at 40℃to near dryness,and 1 ml of reconstitution solution was added to a constant volume.An ACQUITY UPLC BEH C18(100×2.1 mm,2.6μm)chromatographic column was adopted for LC separation by gradient elution with pure water solution-acetonitrile as the mobile phase.For MS detection,the MRM mode was adopted for collection,and the positive and negative ion modes were switched for simultaneous determination,and the internal standard method was used for quantification.[Results]The correlation coefficient R2 was greater than 0.99 in the linear range of each target substance.The limits of quantitation in the method were between 0.05 and 2.00 ng/L,and the recoveries ranged from 75.3%to 105.7%.[Conclusions]The method has high sensitivity,good accuracy and strong practical value. 展开更多
关键词 LANDFILL Endocrine disruptor Solid phase extraction High performance liquid chromatography-tandem mass spectrometry
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Determination of Coumoxystrobin Residue in Vegetables by QeEChERS-UPLC-MS/MS
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作者 zheng liu Shengjiang liu +3 位作者 Yaling liu Qing LI Jun LIANG Xuexue zheng 《Agricultural Biotechnology》 2024年第4期38-39,45,共3页
[Objectives]This study was conducted to establish a method for determining residual coumoxystrobin in vegetables using QeEChERS-liquid chromatography-tandem mass spectrometry(QeEChERS-LC-MS/MS).[Methods]The sample was... [Objectives]This study was conducted to establish a method for determining residual coumoxystrobin in vegetables using QeEChERS-liquid chromatography-tandem mass spectrometry(QeEChERS-LC-MS/MS).[Methods]The sample was extracted by acetonitrile,and the extract was purified by QeEChERS,concentrated by nitrogen blowing,and then detected.[Results]Coumoxystrobin had a good linear relation in the range of 0.01-10.0 mg/kg,and the linear equation was y=4686.92×x+5683.28,R^(2)=0.999.The limit of detection was 0.001 mg/kg,and the limit of quantitation was 0.003 mg/kg.[Conclusions]The method has the advantages of convenient and fast operation and stable detection process,and can provide technical support for the supervision and monitoring of coumoxystrobin. 展开更多
关键词 VEGETABLE UPLC-MS/MS Coumoxystrobin Residual amount
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Study on Detection of Antibiotic Contents in Water around Landfill Sites
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作者 Sha FENG Dandan liu +4 位作者 Juan LUO Qing LI Tao MO zheng liu Xiaonan ZOU 《Agricultural Biotechnology》 2024年第2期33-37,共5页
[Objectives] An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for simultaneous determination of 26 antibiotics in the water around landfills. [Methods] After an H... [Objectives] An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for simultaneous determination of 26 antibiotics in the water around landfills. [Methods] After an HLB solid-phase extraction column was activated, and a water sample, which was adjusted with phosphoric acid to a pH of (2±0.5) and added with 500 mg of disodium EDTA, was loaded, and 5 ml of water and 20% methanol water was added for washing. Next, 10 ml of elution solution was added for elution, and the collected eluate was evaporated under reduced pressure at 40 ℃ to near dryness, and 1 ml of reconstitution solution was added to a constant volume. An ACQUITY UPLC BEH C18 (100 mm×2.1 mm, 2.6 μm) chromatographic column was adopted for LC separation by gradient elution with 0.1% formic acid aqueous solution-acetonitrile as the mobile phase. For MS detection, the MRM mode was adopted for collection, and the positive and negative ion modes were switched for simultaneous determination, and the internal standard method was used for quantification. [Results] The correlation coefficient R2 was greater than 0.99 in the linear range of each target substance. The limits of detection ranged from 0.15 to 3.00 ng/L, and the limits of quantitation were between 0.80 and 10.00 ng/L, and the recoveries ranged from 77.9% to 104.85%. [Conclusions] The method has high sensitivity, good accuracy and strong practical value. 展开更多
关键词 LANDFILL ANTIBIOTICS Ultra high performance liquid chromatography-tandem mass spectrometry
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基于局部窗口交叉注意力的轻量型语义分割
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作者 金祖亮 隗寒冰 +2 位作者 zheng liu 娄路 郑国峰 《汽车工程》 EI CSCD 北大核心 2023年第9期1617-1625,共9页
在自动驾驶汽车环境感知任务中,采用环视相机在统一鸟瞰图(bird′s eye view,BEV)坐标系下对车道线、车辆等目标进行语义分割受到广泛关注。针对相机个数增加致使任务推理延迟线性上升、实时性难以完成语义分割任务的难题,本文提出一种... 在自动驾驶汽车环境感知任务中,采用环视相机在统一鸟瞰图(bird′s eye view,BEV)坐标系下对车道线、车辆等目标进行语义分割受到广泛关注。针对相机个数增加致使任务推理延迟线性上升、实时性难以完成语义分割任务的难题,本文提出一种基于局部窗口交叉注意力的轻量型语义分割方法。采用改进型EdgeNeXt骨干网络提取特征,通过构建BEV查询和图像特征之间的局部窗口交叉注意力,完成对跨相机透视图之间的特征查询,然后对融合后的BEV特征图通过上采样残差块对BEV特征解码,以得到BEV语义分割结果。在nuScenes公开数据集上的实验结果表明,该方法在BEV地图静态车道线分割任务中平均IoU达到35.1%,相较于表现较好的HDMapNet提高2.2%,推理速度相较于较快的GKT提高58.2%,帧率达到106 FPS。 展开更多
关键词 鸟瞰图 语义分割 局部窗口 交叉注意力
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健康管理用于女性代谢综合征患者的效果分析
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作者 伞锕镅 周革利 +2 位作者 张晓彤 郑柳 纪鹏 《智慧健康》 2024年第19期175-178,共4页
目的探讨健康管理用于女性代谢综合征患者的效果。方法选取2022年4月—2023年3月本院接诊的98例代谢综合征患者为研究对象,并使用随机数字表法分为对照组和研究组,每组49例。其中,对照组进行常规管理,研究组进行健康管理,对比两组的各... 目的探讨健康管理用于女性代谢综合征患者的效果。方法选取2022年4月—2023年3月本院接诊的98例代谢综合征患者为研究对象,并使用随机数字表法分为对照组和研究组,每组49例。其中,对照组进行常规管理,研究组进行健康管理,对比两组的各项指标水平及自我管理能力。结果管理前,两组患者的体质指数、腰围、收缩压、舒张压、血糖、TC(总胆固醇)、TG(三酰甘油)、HDL-C(高密度脂蛋白)、LDL-C(低密度脂蛋白)对比,差异无统计学意义(P>0.05);管理后,两组患者各指标均有明显降低,且研究组水平均显著低于对照组(P<0.05)。管理前,两组患者的生活管理、服药管理、生活管理、运动管理、认知管理、急救管理能力评分对比,差异均无统计学意义(P>0.05);管理后,两组患者各指标均有明显提高,且研究组水平均显著高于对照组(P<0.05)。结论健康管理用于女性代谢综合征患者中,能有效改善各项指标水平,提高患者的自我管理能力,对提升治疗效果有积极意义。 展开更多
关键词 健康管理 女性 代谢综合征 效果
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Pharmacological Monitoring of Capecitabine in a Gastric Cancer Patient with Hyperbilirubinemia
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作者 Yanting Gu Qinghua Lang +3 位作者 Dongmei Chen Jianying Zhang zheng liu Ling Gao 《Journal of Biosciences and Medicines》 CAS 2023年第3期120-126,共7页
Objective: To examine therapeutic drug monitoring in managing hyperbilirubinemia caused by capecitabine in patients with gastric adenocarcinoma with extensive liver metastases. Results: The initial liver function test... Objective: To examine therapeutic drug monitoring in managing hyperbilirubinemia caused by capecitabine in patients with gastric adenocarcinoma with extensive liver metastases. Results: The initial liver function tests showed an elevation of transaminases (aspartate amino transferase 615 UI/l, alanine aminotransferase 385.9 UI/l), hyperbilirubinemia (total bilirubin at 246.1 μmol/l), and alkaline phosphatase at 694.6 UI/l. We initiated capecitabine based combination chemotherapy, and the clinical pharmacist conducted a full-course medication monitoring of the patient’s treatment including design of individualized dosing regimens and monitoring of bilirubin, infection, cancer pain, parenteral nutrition support and adverse events. After 21 days of supervision by clinical pharmacist and clinicians, the patient’s bilirubin and transaminase decreased progressively, with aspartate aminotransferase, total bilirubin and alkaline phosphatase falling back to 57 UI/l, 69.8 μmol/l, 307.2 UI/l, respectively. The patient’s condition improved significantly at the time of discharge, with the jaundice subsided, and the bloating relieved. Conclusion: Due to adverse reactions, capecitabine requires medication monitoring during use. The relationship between effectiveness and adverse effects is controversial. Adverse reactions should not be the sole criterion for the use of drugs. Clinical pharmacists can improve the safety and effectiveness of patients’ medications and promote rational drug use by monitoring patients, which may be useful to help the doctors identify the high-risk patients for taking efficient treatment strategy decisions. 展开更多
关键词 Clinical Pharmacist CAPECITABINE Gastric Cancer HYPERBILIRUBINEMIA Therapeutic Drug Monitoring
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Study on Cotton Verticillium Wilt 被引量:1
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作者 Bing CHEN zheng liu 《Plant Diseases and Pests》 CAS 2012年第2期15-20,23,共7页
The pathogen, characteristics, pathogenic mechanism, infection cycle, occurrence regularity and damage symptom of cotton Verticillium wilt are expounded in the paper. The paper puts forward the strategy of protecting ... The pathogen, characteristics, pathogenic mechanism, infection cycle, occurrence regularity and damage symptom of cotton Verticillium wilt are expounded in the paper. The paper puts forward the strategy of protecting disease-free area first, planting resistant varieties and rational rotation in severe area and strengthening the field management, as well as combining with biological control and chemical control methods to effectively control infection and spread of pathogen, so as to provide certain theoretical basis for reducing the damage of cotton Verticillium wilt and improving yield and quality of cotton. 展开更多
关键词 Cotton Verticillium wilt Pathogenic characteristics Occurrence regularity Damage symptoms Prevention measures China
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Concept, Interests and Systems: Logical Consciousness of the China Campus Football Policy Trip
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作者 zheng liu Lizhi liu 《Natural Science》 2023年第6期199-205,共7页
Based on the “Healthy China 2030 Planning Outline”, the literature method and logical analysis method are used to review and analyze the implementation process of China’s school football policy from three dimension... Based on the “Healthy China 2030 Planning Outline”, the literature method and logical analysis method are used to review and analyze the implementation process of China’s school football policy from three dimensions: value, interest appeal and institutional background. The study believes that in order to break through the bottleneck of policy implementation and improve the effect of policy implementation, it is necessary to establish correct values and form broad recognition of policies;meet the reasonable interests of all parties and form a synergy for policy implementation;optimize the institutional environment for policy implementation and form effective incentives. 展开更多
关键词 School Football Policy Enforcement Healthy China Three-Dimensional Structure of Human Reason Path Selection
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Design and Data Analysis of a New Type of Antifreezing Cup-Type Wind Velocity Sensor
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作者 Jiajia Zhang Jianguang Han +2 位作者 Jianan Yin zheng liu Ting Ma 《World Journal of Engineering and Technology》 2023年第4期672-681,共10页
In most areas of China, affected by the environment of low temperature and high humidity, the wind speed sensor and wind direction sensor are frozen and cannot output data in autumn, winter or the alternation of winte... In most areas of China, affected by the environment of low temperature and high humidity, the wind speed sensor and wind direction sensor are frozen and cannot output data in autumn, winter or the alternation of winter and spring. In order to solve the freezing situation of the wind sensor, this paper designs a new type of antifreeze wind speed sensor. After meteorology performance testing and field observation tests, the correlation coefficient of the observation data is demonstrated, and the data curve is fitted. The result shows the sensor is stable, and has a good antifreeze effect, the data output is reliable. 展开更多
关键词 Automatic Weather Station Wind Speed Sensor Wind Direction Sensor Freeze Cold-Resistant Technology
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