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基于SMART原则的TSDF椅旁教学在口腔四手操作护理带教中的应用
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作者 张彩霞 金依蓓 +1 位作者 廖慧洁 叶苗苗 《中国高等医学教育》 2025年第4期86-87,共2页
目的:研究基于SMART原则的TSDF椅旁教学在口腔四手操作护理带教中的应用效果。方法:随机将本院60名护生分为两组,30名设为对照组,采用TSDF椅旁教学;30名设为试验组,采用基于SMART原则的TSDF椅旁教学。带教结束后对两组护生进行教学效果... 目的:研究基于SMART原则的TSDF椅旁教学在口腔四手操作护理带教中的应用效果。方法:随机将本院60名护生分为两组,30名设为对照组,采用TSDF椅旁教学;30名设为试验组,采用基于SMART原则的TSDF椅旁教学。带教结束后对两组护生进行教学效果评估。结果:试验组的口腔四手操作考核成绩及口腔四手操作规范执行率均高于对照组(P<0.05)。结论:在口腔四手操作护理带教中应用基于SMART原则的TSDF椅旁教学,能够进一步提高护生的口腔四手操作考核成绩和规范执行率。 展开更多
关键词 SMART原则 tsdf椅旁教学 口腔四手操作 护理带教
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TSDF教学模式在护理学基础实践教学中的应用——以养老服务管理专业为例 被引量:1
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作者 岑爱丽 黄丽萍 +3 位作者 曾金艳 杜玉环 姚欣 卢利 《卫生职业教育》 2025年第3期73-76,共4页
目的探讨TSDF(tell,激活;show,连接;do,归纳;feedback,反思)教学模式在养老服务管理专业护理学基础实践教学中的应用效果。方法将2021级48名养老服务管理专业学生作为对照组,采用传统教学模式;将2022级51名养老服务管理专业学生作为观察... 目的探讨TSDF(tell,激活;show,连接;do,归纳;feedback,反思)教学模式在养老服务管理专业护理学基础实践教学中的应用效果。方法将2021级48名养老服务管理专业学生作为对照组,采用传统教学模式;将2022级51名养老服务管理专业学生作为观察组,采用TSDF教学模式,比较两组学生临床实践综合能力、自我导向学习能力、自主学习能力、实践技能操作考核成绩及对教学模式的满意度。结果观察组临床实践综合能力、自我导向学习能力、自主学习能力、实践技能操作考核成绩及对教学模式的满意度均优于对照组(P<0.05)。结论TSDF教学模式在养老服务管理专业护理学基础实践教学中的应用效果较好,值得推广。 展开更多
关键词 tsdf教学模式 养老服务管理专业 护理学基础 实践教学
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Post-translational cleavage generates truncated IgY forms in the snake Elaphe taeniura
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作者 Ming Zhang Long Hua +10 位作者 Tang-Yuan Xie Tao Wang Li-Juan Du Di Yu Han-Wei Cao Jin-Cheng Zhong Geng-Sheng Cao Xiang Ding Hai-Tang Han Yao-Feng Zhao Tian Huang 《Zoological Research》 2025年第2期277-284,共8页
While variable regions of immunoglobulins are extensively diversified by V(D)J recombination and somatic hypermutation in vertebrates,the constant regions of immunoglobulin heavy chains also utilize certain mechanisms... While variable regions of immunoglobulins are extensively diversified by V(D)J recombination and somatic hypermutation in vertebrates,the constant regions of immunoglobulin heavy chains also utilize certain mechanisms to produce diversity,including class switch recombination(CSR),subclass differentiation,and alternative expression of the same gene.Many species of birds,reptiles,and amphibians express a truncated isoform of immunoglobulin Y(IgY),termed IgY(ΔFc),which lacks theυCH3 andυCH4 domains.In Anseriformes,IgY(ΔFc)arises from alternative transcriptional termination sites within the sameυgene,whereas in some turtles,intact IgY and IgY(ΔFc)are encoded by distinct genes.Different from the previously reported IgY(ΔFc)variants,this study identified a truncated IgY in the snake Elaphe taeniura,characterized by the loss of only a portion of the CH4 domain.Western blotting and liquid chromatographytandem mass spectrometry confirmed that this truncated IgY is generated by post-translational cleavage at N338 within the IgY heavy chain constant(CH)region.Furthermore,both human and snake asparaginyl endopeptidase were shown to cleave snake IgY in vitro.These findings reveal a novel mechanism for the production of shortened IgY forms,demonstrating that the immunoglobulin CH region undergoes diversification through distinct strategies across vertebrates. 展开更多
关键词 truncated IgY Post-translational cleavage Asparaginyl endopeptidase
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A Novel Mouse Model Unveils Protein Deficiency in Truncated CDKL5 Mutations
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作者 Xue Feng Zi-Ai Zhu +5 位作者 Hong-Tao Wang Hui-Wen Zhou Ji-Wei Liu Ya Shen Yu-Xian Zhang Zhi-Qi Xiong 《Neuroscience Bulletin》 2025年第5期805-820,共16页
Mutations in the cyclin-dependent kinase-like 5 gene(CDKL5)cause a severe neurodevelopmental disorder,yet the impact of truncating mutations remains unclear.Here,we introduce the Cdkl5^(492stop) mouse model,mimicking ... Mutations in the cyclin-dependent kinase-like 5 gene(CDKL5)cause a severe neurodevelopmental disorder,yet the impact of truncating mutations remains unclear.Here,we introduce the Cdkl5^(492stop) mouse model,mimicking C-terminal truncating mutations in patients.492stop/Y mice exhibit altered dendritic spine morphology and spontaneous seizure-like behaviors,alongside other behavioral deficits.After creating cell lines with various Cdkl5 truncating mutations,we found that these mutations are regulated by the nonsense-mediated RNA decay pathway.Most truncating mutations result in CDKL5 protein loss,leading to multiple disease phenotypes,and offering new insights into the pathogenesis of CDKL5 disorder. 展开更多
关键词 Cdkl5 Truncating mutations CDKL5 defciency disorder Nonsense-mediated RNA decay
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Improved photocatalytic performance of acetaldehyde degradation via crystal plane regulation on truncated octahedral CeO_(2) 被引量:3
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作者 Bin Xu Lu Jia +6 位作者 Hui Yang Yue Wang Si-Yu Fan Sai-Sai Yuan Qi-TaoZhang Ming Zhang Teruhisa Ohno 《Rare Metals》 SCIE EI CAS CSCD 2024年第5期2026-2038,共13页
In this study,the truncated octahedral CeO_(2)(CeO_(2)-to)with special morphology was prepared by the solvothermal method with oleic acid(OA)and oleamine(OM)as the morphology-directing agents.High-resolution transmiss... In this study,the truncated octahedral CeO_(2)(CeO_(2)-to)with special morphology was prepared by the solvothermal method with oleic acid(OA)and oleamine(OM)as the morphology-directing agents.High-resolution transmission electron microscopy(HRTEM)results show that CeO_(2)-to exposes composite{100}and{111}facets,while CeO_(2)cubic(CeO_(2)-c)and CeO_(2)octahedral(CeO_(2)-o)only expose single crystal facets of{100}plane and{111}plane,respectively.Interestingly,this CeO_(2)-to photocatalyst exhibits remarkable photooxidation performance of gaseous acetaldehyde(CH_(3)CHO)degradation,in which CO_(2)generation value reaches 1.78 and 7.97-times greater than that of CeO_(2)-c and CeO_(2)-o,respectively.In addition,the active species trapping experiment signifies that superoxide(·O_(2)^(-))and holes(h^(+))are the main reactive substances during the CH_(3)CHO degradation process,and the electron paramagnetic resonance(EPR)spectra indicates that the former is the major contributor.Notably,the electron transfer mechanism between CeO_(2)-to{100}and{111}facets and the surface oxygen adsorption ability are revealed via density functional theory(DFT)calculations.It is also confirmed that{100}facets are more conducive to the absorption of acetaldehyde than{111}facets.Finally,a reasonable mechanism for improved photocatalytic CH_(3)CHO degradation on CeO_(2)-to is proposed based on relevant experiments and DFT calculations.This study demonstrates that the systematic development of surface homojunction structured photocatalysts can efficiently increase the degradation activity for volatile organic compounds(VOCs).It also offers additional direction for optimizing the photocatalytic activity of other ceriumbased photocatalysts. 展开更多
关键词 truncated octahedral CeO_(2)(CeO_(2)-to) Composite crystal faces Surface energy level Efficient electrontransfer
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TSDF椅旁教学对口腔规范化培训住院医师共情能力的影响
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作者 王泽凤 刘燕美 傅柏平 《中国高等医学教育》 2024年第11期132-133,共2页
目的:探讨TSDF椅旁教学对口腔规范化培训住院医师共情能力的影响。方法:选取2019级、2020级、2021级在浙江大学医学院附属口腔医院进行规范化培训的75名住院医师,以杰弗逊共情量表医生版(JSE-HP)为测量工具进行问卷调查。结果:不同年级... 目的:探讨TSDF椅旁教学对口腔规范化培训住院医师共情能力的影响。方法:选取2019级、2020级、2021级在浙江大学医学院附属口腔医院进行规范化培训的75名住院医师,以杰弗逊共情量表医生版(JSE-HP)为测量工具进行问卷调查。结果:不同年级住院医师在JSE-HP总分及各因子得分上均无显著性差异。不同学历住院医师在JSE-HP总分及观点采择得分上无显著性差异,在情感护理和换位思考上的得分博士组明显低于本科组和硕士组(P<0.05)。结论:TSDF椅旁教学需结合医学人文教育以提高口腔住院医师的共情能力。 展开更多
关键词 共情能力 住院医师规范化培训 tsdf椅旁教学
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Continuity of truncated Hardy-Littlewood maximal function
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作者 WANG Yidong WU Jia YAN Dunyan 《中国科学院大学学报(中英文)》 CAS CSCD 北大核心 2024年第6期721-727,共7页
This paper focuses on the continuity of the truncated Hardy-Littlewood maximal function.We first show that the truncated Hardy-Littlewood maximal function is lower semi-continuous.Then by investigating the behavior of... This paper focuses on the continuity of the truncated Hardy-Littlewood maximal function.We first show that the truncated Hardy-Littlewood maximal function is lower semi-continuous.Then by investigating the behavior of the truncated Hardy-Littlewood maximal function when the truncated parameterγchanges,we obtain an equivalent condition of the continuity of the truncated Hardy-Littlewood maximal function. 展开更多
关键词 Hardy-Littlewood maximal function TRUNCATION CONTINUITY truncated parameter
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Analytical Solution and Simplified Formula for Added Mass of Horizontal and Vertical Motions of Truncated Cylinders Under Earthquake Action
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作者 WANG Pi-guang LYU Si-yu +2 位作者 QU Yang ZHAO Mi DU Xiu-li 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期54-67,共14页
This paper investigates the hydrodynamic characteristics of floating truncated cylinders undergoing horizontal and vertical motions due to earthquake excitations in the finite water depth.The governing equation of the... This paper investigates the hydrodynamic characteristics of floating truncated cylinders undergoing horizontal and vertical motions due to earthquake excitations in the finite water depth.The governing equation of the hydrodynamic pressure acting on the cylinder is derived based on the radiation theory with the inviscid and incompressible assumptions.The governing equation is solved by using the method of separating variables and analytical solutions are obtained by assigning reasonable boundary conditions.The analytical result is validated by a numerical model using the exact artificial boundary simulation of the infinite water.The main variation and distribution characteristics of the hydrodynamic pressure acting on the side and bottom of the cylinder are analyzed for different combinations of wide-height and immersion ratios.The added mass coefficient of the cylinder is calculated by integrating the hydrodynamic pressure and simplified formulas are proposed for engineering applications.The calculation results show that the simplified formulas are in good agreement with the analytical solutions. 展开更多
关键词 EARTHQUAKE hydrodynamic pressure truncated cylinder added mass simplified formula
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CRISPR/Cas9-mediated NlInR2 mutants:Analyses of residual mRNA and truncated proteins
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作者 Jun Lü Jingxiang Chen +4 位作者 Yutao Hu Lin Chen Shihui Li Yibing Zhang Wenqing Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2006-2017,共12页
CRISPR/Cas9 technology is a powerful genome manipulation tool in insects.However,little is known about whether mRNA and protein of a target gene are completely cleared in homozygous mutants.This study generated homozy... CRISPR/Cas9 technology is a powerful genome manipulation tool in insects.However,little is known about whether mRNA and protein of a target gene are completely cleared in homozygous mutants.This study generated homozygous mutants of the insulin receptor gene 2(NlInR2)in the brown planthopper(Nilaparvata lugens)using CRISPR/Cas9 genome editing.Both frameshift mutants,E5_D17 and E6_I7,differentiated towards long wings,but there were differences in wing morphology,with E5_D17 showing wing deformities.Subsequent investigations revealed the presence of residual expression of NlInR2 mRNA in both mutants,as well as the occurrence of spliceosomes featuring exon skipping splicing in E5_D17.Additionally,the E5_D17 exhibited the detection of N-terminally truncated NlInR2 protein.RNA interference experiments indicated that the knockdown of NlInR2 expression in the E5_D17 mutant line increased the proportion of wing deformities from 11.1 to 65.6%,suggesting that the residual NlInR2 mRNA of the E5_D17 mutant might have retained some genetic functions.Our results imply that systematic characterization of residual protein expression or function in CRISPR/Cas9-generated mutant lines is necessary for phenotypic interpretation. 展开更多
关键词 CRISPR/Cas9 Nilaparvata lugens residual mRNA skipping exon truncated protein
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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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Quercetin inhibits truncated isoform of dopamine-and cAMP-regulated phosphoprotein as adjuvant treatment for trastuzumab therapy resistance in HER2-positive breast cancer
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作者 Han-Sheng Chang Tzu-Chun Cheng +6 位作者 Shih-Hsin Tu Chih-Hsiung Wu You-Cheng Liao Jungshan Chang Min-Hsiung Pan Li-Ching Chen Yuan-Soon Ho 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2653-2667,共15页
Trastuzumab resistance is one of the causes of poor prognosis in patients with human epidermal growth factor receptor 2(HER2)-positive(HER2+)breast cancer(BC).The truncated isoform of dopamine-and cAMPregulated phosph... Trastuzumab resistance is one of the causes of poor prognosis in patients with human epidermal growth factor receptor 2(HER2)-positive(HER2+)breast cancer(BC).The truncated isoform of dopamine-and cAMPregulated phosphoprotein(t-DARPP)has been reported to be involved in trastuzumab therapy resistance and promoting tumor progression.To evaluate the t-DARPP expression in BC,paired tumors and surrounding normal tissues were analyzed by real-time polymerase chain reaction and confirmed higher DARPP-32 kDa family mRNA expression in HER2+BC tumor tissues.We established 2 patient-derived xenografts(PDX)mice models to test the efficacy of trastuzumab,named model 1(non-responder)and model 2(responder).t-DARPP and p95-HER2 protein-protein interactions were detected in PDX tumor tissue from non-responders using Förster resonance energy transfer assays.Instead,there is no response from the responder.Furthermore,mechanistic studies using transwell and western blot assays demonstrated that t-DARPP could upregulate epithelial-mesenchymal transition signaling proteins,enhance p95-HER2 expression and promote cell migration.We found that quercetin effectively reduced t-DARPP expression in HER2+BC cells.In t-DARPP ShRNA-suppressed cells,quercetin synergistically enhanced trastuzumab-induced apoptotic cell death and G2/M phase arrest.In conclusion,the combination of quercetin and trastuzumab treatment by targeting t-DARPP in HER2+BC patients has the potential as a biomarker for mitigating drug resistance. 展开更多
关键词 p95-Human epidermal growth factor receptor 2 (HER2) HER2-positive breast cancer QUERCETIN Trastuzumab resistance truncated isoform of dopamine-and cAMPregulated PHOSPHOPROTEIN
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一种基于截短N蛋白的猪丁型冠状病毒抗体ELISA检测方法的建立 被引量:1
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作者 王东升 于瑞明 +5 位作者 张莉萍 白英杰 刘霞 王永录 杜晓华 刘新生 《生物工程学报》 北大核心 2025年第7期2760-2773,共14页
为了建立一种猪丁型冠状病毒(porcine deltacoronavirus,PDCoV)抗体检测方法,将PDCoV CH/XJYN/2016毒株N基因序列插入原核表达质粒载体pColdⅡ中,表达重组蛋白PDCoV-N1和PDCoV-N2,经SDS-PAGE分析和Ni+-NTA纯化后,检测重组原核蛋白PDCoV... 为了建立一种猪丁型冠状病毒(porcine deltacoronavirus,PDCoV)抗体检测方法,将PDCoV CH/XJYN/2016毒株N基因序列插入原核表达质粒载体pColdⅡ中,表达重组蛋白PDCoV-N1和PDCoV-N2,经SDS-PAGE分析和Ni+-NTA纯化后,检测重组原核蛋白PDCoV-N1和PDCoV-N2与猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV)阳性血清的反应原性和特异性。同时对重组真核蛋白PDCoV-N1和PDCoV-N2进行Western blotting和间接免疫荧光实验验证分析。最后使用重组原核蛋白PDCoV-N2建立间接ELISA方法,优化反应条件,检测敏感性、特异性及重复性,并对102份临床血清进行了检测。重组原核蛋白PDCoV-N2与PEDV抗血清交叉反应较低。以PDCoV-N2蛋白制备的间接ELISA方法的最优条件为:抗原包被浓度1.25μg/mL,37℃包被1 h,BSA封闭液4℃过夜,血清最佳稀释浓度1:50,37℃孵育1 h,酶标二抗最佳稀释比例为1:80000,37℃孵育1 h,加入四甲基联苯胺(tetramethylbenzidine,TMB)显色液37℃反应10 min。待检样品的S/P值(样本值–阴性对照值)/(阳性对照值–阴性对照值)≥0.45为阳性,S/P值≤0.38为阴性,S/P值介于0.45和0.38之间,则为可疑。检测猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV)、猪圆环病毒2型(porcine circovirus 2,PCV2)、猪传染性胃肠炎病毒(transmissiblegastroenteritis of swine,TGEV)、口蹄疫病毒(foot-and-mouth disease virus,FMDV)、非洲猪瘟病毒(african swine fever virus,ASFV)阳性血清,结果显示,其他冠状病毒的S/P值均小于0.38,表明其具有良好的特异性;PDCoV抗血清800倍稀释后仍为阳性;批间和批内重复性实验结果显示,本方法变异系数均小于10%;临床血清样本检测结果显示,该方法与中和实验的符合率为94.12%。本研究基于截短的PDCoV N蛋白,建立了能够检测抗PDCoV特异性IgG抗体的ELISA方法,且该方法敏感、特异、稳定、重复性好,为PDCoV的临床诊断提供了新的方法。 展开更多
关键词 猪δ冠状病毒 截短N蛋白 IGG抗体 间接ELISA
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N-terminal truncated phospholipase A1 accessory protein PlaS from Serratia marcescens alleviates inhibitory on host cell growth and enhances PlaA1 enzymatic activity
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作者 Mengkai Hu Jun Liu +7 位作者 Yufei Gan Hao Zhu Rumeng Han Kun Liu Yan Liu Ming Zhao Xiangfei Li Zhenglian Xue 《Bioresources and Bioprocessing》 2024年第1期823-834,共12页
Phospholipase A1(PLA1)is a kind of specific phospholipid hydrolase widely used in food,medical,textile.However,limitations in its expression and enzymatic activity have prompted the investigation of the phospholipase-... Phospholipase A1(PLA1)is a kind of specific phospholipid hydrolase widely used in food,medical,textile.However,limitations in its expression and enzymatic activity have prompted the investigation of the phospholipase-assisting protein PlaS.In this study,we elucidate the role of PlaS in enhancing the expression and activity of PlaA1 through N-terminal truncation.Our research demonstrates that truncating the N-terminal region of PlaS effectively overcomes its inhibitory effect on host cells,resulting in improved cell growth and increased protein solubility of the protein.The yeast two-hybrid assay confirms the interaction between PlaA1 and N-terminal truncated PlaS(ΔN27 PlaS),highlighting their binding capabilities.Furthermore,in vitro studies using Biacore analysis reveal a concentration-dependent and specific binding between PlaA1 andΔN27 PlaS,exhibiting high affinity.Molecular docking analysis provides insights into the hydrogen bond interactions betweenΔN27 PlaS and PlaA1,identifying key amino acid residues crucial for their binding.Finally,the enzyme activity of PLA1 was boost to 8.4 U/mL by orthogonal test.Study significantly contributes to the understanding of the interaction mechanism between PlaS and PlaA1,offering potential strategies for enhancing PlaA1 activity through protein engineering approaches. 展开更多
关键词 Phospholipase A1 PLAS N-terminal truncation Protein-protein interaction Enzymatic activity
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树体管理对落叶松种子园母树生理特性的影响
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作者 卜鹏图 冯健 +2 位作者 杨圆圆 孙丽娟 李光 《森林工程》 北大核心 2025年第6期1174-1181,共8页
落叶松是我国北方地区重要的人工林树种。为揭示树体管理对落叶松母树生理影响,以落叶松2代种子园母树为研究对象,采用截干(TT)、拉枝(PB)及截干+拉枝(TT+PB)的处理,测定并分析落叶松母树结实枝中内源激素、营养物质、氧化酶、丙二醛(M... 落叶松是我国北方地区重要的人工林树种。为揭示树体管理对落叶松母树生理影响,以落叶松2代种子园母树为研究对象,采用截干(TT)、拉枝(PB)及截干+拉枝(TT+PB)的处理,测定并分析落叶松母树结实枝中内源激素、营养物质、氧化酶、丙二醛(MDA)及游离脯氨酸等生理指标。结果表明,从内源激素质量分数上看,截干和拉枝促进落叶松母树结实枝中吲哚乙酸(IAA)、赤霉素(GA3)和玉米素(ZT)质量分数的增加,而降低了脱落酸(ABA)的质量分数。尤其是截干和拉枝相结合(TT+PB)的处理,其IAA、GA3和ZT质量分数分别是对照(CK)的107.80%、108.61%和107.29%。从内源激素比例上看,树体管理提高了IAA/ABA、GA3/ABA、ZT/ABA、GA3/IAA、ZT/IAA和ZT/GA3的比值。树体管理增加了落叶松母树结实枝内可溶性蛋白、淀粉和可溶性糖的质量分数,尤其是TT+PB效果最为显著,其可溶性蛋白、淀粉和可溶性糖质量分数分别是CK的103.09%,115.99%和104.40%。树体管理提高了超氧化物岐化酶(SOD)和过氧化物酶(POD)的活性,提高了落叶松母树的抗性。综上所述,树体管理技术为落叶松母树种子产量和质量的提高提供了充足的物质基质。研究结果为落叶松种子园丰产和稳产提供理论支撑。 展开更多
关键词 落叶松 拉枝 截干 激素
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新城疫病毒HN蛋白的截短表达及间接ELISA方法建立
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作者 魏玲 王思怡 +4 位作者 熊荣园 梁洪 王怀禹 李彩虹 杨国淋 《家畜生态学报》 北大核心 2025年第3期91-95,共5页
为了建立一种快速的新城疫病毒(Newcastle disease virus,NDV)抗体检测方法,试验采用原核表达技术表达HN蛋白,以HN蛋白为检测抗原建立酶联免疫吸附测定(Enzyme linked immunosorbent assay,ELISA)方法。结果表明,获得了以包涵体形式表... 为了建立一种快速的新城疫病毒(Newcastle disease virus,NDV)抗体检测方法,试验采用原核表达技术表达HN蛋白,以HN蛋白为检测抗原建立酶联免疫吸附测定(Enzyme linked immunosorbent assay,ELISA)方法。结果表明,获得了以包涵体形式表达的重组蛋白,间接ELISA方法检测6种其它鸡病阳性血清均为阴性,其最低抗体检出效价为1∶10240,其与血凝抑制试验(Hemagglutination inhibition,HI)方法的阳性和阴性符合率分别为98.08%和92.31%,检测临床样品阳性率为91.48%。说明建立的间接ELISA方法可用于NDV免疫抗体检测和疫苗免疫效果评价。 展开更多
关键词 新城疫病毒 HN蛋白 截短表达 间接ELISA 抗体检测
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核电仪控卡件运行MTBF评估方法研究
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作者 莫昌瑜 李刚 +3 位作者 李明利 胡俊 吴彬 朱丽玲 《核动力工程》 北大核心 2025年第3期295-302,共8页
核电仪控卡件运行平均故障间隔时间(MTBF)评估对故障根本原因分析、电厂维修老化管理和智能运维技术研究有重要意义。然而,现阶段由于核电行业缺乏统一的技术标准,实际工程应用中主要采用简单求平均来计算运行MTBF,此算法不考虑责任故... 核电仪控卡件运行平均故障间隔时间(MTBF)评估对故障根本原因分析、电厂维修老化管理和智能运维技术研究有重要意义。然而,现阶段由于核电行业缺乏统一的技术标准,实际工程应用中主要采用简单求平均来计算运行MTBF,此算法不考虑责任故障定义、失效分布拟合情况,也无法给出更有指导意义的区间估计。为优化当前算法,本研究提出了一种基于多失效分布拟合优度检验的核电仪控卡件运行MTBF评估方法,首先给出需要纳入评估范围的责任故障定义准则,并依据此准则进行故障筛选与统计;其次建立了针对定时截尾数据的4种失效分布参数估计似然方程,并应用皮尔逊检验和贝叶斯信息准则(BIC),开展拟合优度检验与最优分布选择,在此基础上计算出一定置信度下仪控卡件的运行MTBF。使用此方法对某核电机组商运状态下的继电器输出板卡进行了研究实践,应用结果表明,此方法得到的继电器输出卡件运行MTBF评估结果,包含点估计与区间估计结果,综合考虑了失效分布、数据样本特征和信息损失量的贡献,要比现阶段常规作法更合理、结果更准确。因此,本研究建立的核电仪控卡件运行MTBF评估方法能够应用于工程化的核电仪控卡件故障分析。 展开更多
关键词 核电仪控卡件 平均故障间隔时间(MTBF) 失效分布 定时截尾 拟合优度检验
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基于体积结构重建网格地图的激光SLAM算法 被引量:1
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作者 李维刚 陈宇飞 王永强 《武汉科技大学学报》 北大核心 2025年第4期300-308,共9页
在激光同步定位和建图(SLAM)中,网格地图因蕴含丰富的几何信息且内存消耗相对较低,已成为备受关注的地图表示结构。构建网格地图常用的截断带符号距离函数(TSDF)重建法虽然效率较高,但其需要通过先验知识估测无界点云的空间,从而局限了... 在激光同步定位和建图(SLAM)中,网格地图因蕴含丰富的几何信息且内存消耗相对较低,已成为备受关注的地图表示结构。构建网格地图常用的截断带符号距离函数(TSDF)重建法虽然效率较高,但其需要通过先验知识估测无界点云的空间,从而局限了网格结构的范围。为此提出一种基于体积结构重建网格地图的激光SLAM算法。首先,采用计算机图形学中对无界体积进行建模的VDB体积结构,将其作为点云对应TSDF的无界映射载体,以解决TSDF重建的网格固定问题;然后,基于VDB体积的体素结构提出邻近网格搜索和配准算法;最后,采用截断射线法完成VDB体积的更新,并基于体元法重建网格地图。在KITTI数据集多个数据序列上进行实验,结果表明,本文算法的重建地图相较原始点云节省了60%的内存空间,重建精度和定位精度均优于对比SLAM算法。 展开更多
关键词 SLAM 网格地图 VDB体积 表面重建 tsdf 点云配准
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基于蒙特卡洛算法下宫颈癌放疗计划退行性迭代的研究
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作者 陈宏林 陈晶晶 +1 位作者 杨玉荟 苗慧 《中国医疗设备》 2025年第7期49-53,75,共6页
目的研究Monaco治疗计划系统(Treatment Planning System,TPS)在宫颈癌放射治疗(简称“放疗”)中退行性剂量迭代的触发因素以及高剂量迭代位置截断计算方案的可行性。方法选取2023年6月1日至2024年4月1日间实施宫颈癌容积旋转调强治疗(V... 目的研究Monaco治疗计划系统(Treatment Planning System,TPS)在宫颈癌放射治疗(简称“放疗”)中退行性剂量迭代的触发因素以及高剂量迭代位置截断计算方案的可行性。方法选取2023年6月1日至2024年4月1日间实施宫颈癌容积旋转调强治疗(Volumetric Modulated Arctherapy,VMAT)的30例患者为研究对象,处方剂量为45 Gy/25 F,每例患者设计2个全弧VMAT计划。在通量优化结束后,通过Progress Meter统计复杂度系数(Modulation Degree,MD)并依据差异率将实验病例分为High MD组与Low MD组,分析2组计划靶区(Planning Target Volume,PTV)的V_(45)(器官接受至少45 Gy剂量的体积百分比,其他以此类推)通量优化与剂量优化结果间的差异率;对High MD组病例进一步研究,分析在靶区剂量的最高体积覆盖处进行截断的高位截断计划组(Plan HLC)与常规自动完成计划组Plan A的PTV的V_(45)及主要危及器官(Organs At Risk,OARs)的剂量学、计划特征参数、计划剂量分布和计划验证结果间的差异。结果对入组30例病例的MD值进行统计,High MD组(MD>3)有19例,占63.3%,Low MD组(MD<3)有11例,占37.7%。High MD组的PTV的V_(45)通量优化结果与剂量优化结果差异率明显高于Low MD组;在High MD组的剂量迭代全过程中,PTV的V_(45)达到峰值后可见明显的跌落。在对Plan A与Plan HLC实验病例的进一步分析中,靶区和主要OARs的剂量差异均有统计学意义[PTV的V_(45):t=3.116,P=0.013;小肠D_(0.03cc)(0.03 cm^(3)体积的最大剂量值):t=1.241,P=0.022;直肠V_(40):t=6.183,P=0.021;膀胱V_(40):t=3.174,P=0.032]。剂量云图及剂量体积直方图的分析显示,2组差异趋势相近;剂量优化特征参数的统计结果表明,2组各项结果差异均有统计学意义(X线蒙特卡洛算法剂量优化时间:t=1.607、P=0.001;计划光子利用率:t=4.962、P=0.023;子野数量:t=2.512、P=0.022;机器跳数:t=8.201、P=0.001);2组计划的验证结果均符合临床要求,但Plan A组略高于Plan HLC组。结论应用Monaco5.11 TPS进行优化宫颈癌放疗计划,MD值是触发退行性迭代的主要因素;在发生退行性迭代时的高剂量迭代位置截停计划符合临床实施条件,获取的Plan HLC计划可被用于放疗。 展开更多
关键词 Monaco计划系统 宫颈癌 退行性迭代 复杂度系数 截断计算方案 触发因素
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基于截断温度法的倾斜采空区自燃带计算机模拟
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作者 周延 耿玉德 +2 位作者 王江 刘鑫 武建国 《煤炭技术》 2025年第5期203-207,共5页
通过比较采空区自燃带计算机模拟的不同方法,阐明了截断温度法的原理优势。以唐山矿的一个设计采面为例,采用截断温度法对其采空区自燃带的3维形态进行了计算机模拟。结果表明:对于倾斜采空区,当采面为上行通风时,在“热风压”和“瓦斯... 通过比较采空区自燃带计算机模拟的不同方法,阐明了截断温度法的原理优势。以唐山矿的一个设计采面为例,采用截断温度法对其采空区自燃带的3维形态进行了计算机模拟。结果表明:对于倾斜采空区,当采面为上行通风时,在“热风压”和“瓦斯风压”的作用下,会有更多的风流漏入采空区,导致采空区冷却带和进风侧自燃带明显增宽;当遗煤厚度较大时,自燃带的位置和宽度在垂直于煤层底板的方向上会发生很大变化。由于自燃“三带”现场观测测点数量有限且通常只能布置在某个特定高度上,如果在采面安全设计中简单地套用已有的现场观测结果,容易误判自燃带位置、低估自燃带宽度,给采空区防火带来不利影响。 展开更多
关键词 倾斜采空区 自燃带 3维形态 计算机模拟 截断温度
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猪轮状病毒VP6蛋白截短表达及间接ELISA抗体检测方法的建立 被引量:4
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作者 潘向英 曾智勇 +7 位作者 梁海英 汤德元 王彬 叶泥 田红利 边孟婷 柳佳佳 黄书 《中国畜牧兽医》 北大核心 2025年第3期1231-1240,共10页
【目的】通过构建猪轮状病毒(Porcine rotavirus,PoRV)VP6截短蛋白(第177—382位氨基酸)的原核表达系统,建立检测PoRV抗体的间接ELISA方法,为PoRV血清学监测提供检测手段。【方法】设计1对针对截短VP 6基因的特异性引物,以pMD19-T-VP6... 【目的】通过构建猪轮状病毒(Porcine rotavirus,PoRV)VP6截短蛋白(第177—382位氨基酸)的原核表达系统,建立检测PoRV抗体的间接ELISA方法,为PoRV血清学监测提供检测手段。【方法】设计1对针对截短VP 6基因的特异性引物,以pMD19-T-VP6重组质粒为模板扩增VP 6截短基因。利用pET-32a(+)原核表达载体构建pET32a-PoRV-VP6重组质粒。以大肠杆菌Rosetta(DE3)感受态细胞为宿主菌,对重组质粒进行诱导表达,并优化表达条件。利用His标签镍柱对pET32a-PoRV-VP6重组蛋白进行纯化,以此作为包被抗原,通过单一变量法优化抗原包被浓度、血清稀释度、二抗稀释度及一抗、二抗孵育时间等工作条件。确定间接ELISA方法的阴阳性临界值,检验其特异性、敏感性、重复性及符合性,并对2021—2024年采自贵州地区不同猪场的384份临床猪血清进行检测。【结果】试验成功构建pET32a-PoRV-VP6重组表达载体,实现VP6蛋白的原核截短表达,蛋白分子质量大小约40 ku,具有良好的反应原性。对间接ELISA方法条件进行优化,确定VP6包被抗原最佳浓度为2μg/mL、阳性血清稀释度为1∶100、血清样品和二抗孵育时间均为60 min、TMB反应时间为10 min、阴阳性临界值(D 450 nm)为0.410。建立的间接ELISA方法与猪流行性腹泻病毒(PEDV)、猪冠状病毒(PDCoV)、猪传染性胃肠炎病毒(TGEV)等病毒标准阳性血清不发生反应,特异性强;批内和批间重复试验变异系数均<10%,重复性好;与PoRV A型ELISA抗体检测试剂盒的总体符合率为96.80%。间接ELISA方法检测临床384份猪血清样品结果显示,样品总阳性率为28.91%。【结论】本研究成功实现了PoRV VP6蛋白的截短表达,并建立了PoRV间接ELISA抗体检测方法,适用于临床PoRV抗体检测和疫苗免疫效果评价。 展开更多
关键词 猪轮状病毒(PoRV) VP6蛋白 截短表达 间接ELISA
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