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ATFF: Advanced Transformer with Multiscale Contextual Fusion for Medical Image Segmentation
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作者 Xinping Guo lei wang +2 位作者 Zizhen Huang Yukun Zhang Yaolong Han 《Journal of Computer and Communications》 2024年第3期238-251,共14页
Deep convolutional neural network (CNN) greatly promotes the automatic segmentation of medical images. However, due to the inherent properties of convolution operations, CNN usually cannot establish long-distance inte... Deep convolutional neural network (CNN) greatly promotes the automatic segmentation of medical images. However, due to the inherent properties of convolution operations, CNN usually cannot establish long-distance interdependence, which limits the segmentation performance. Transformer has been successfully applied to various computer vision, using self-attention mechanism to simulate long-distance interaction, so as to capture global information. However, self-attention lacks spatial location and high-performance computing. In order to solve the above problems, we develop a new medical transformer, which has a multi-scale context fusion function and can be used for medical image segmentation. The proposed model combines convolution operation and attention mechanism to form a u-shaped framework, which can capture both local and global information. First, the traditional converter module is improved to an advanced converter module, which uses post-layer normalization to obtain mild activation values, and uses scaled cosine attention with a moving window to obtain accurate spatial information. Secondly, we also introduce a deep supervision strategy to guide the model to fuse multi-scale feature information. It further enables the proposed model to effectively propagate feature information across layers, Thanks to this, it can achieve better segmentation performance while being more robust and efficient. The proposed model is evaluated on multiple medical image segmentation datasets. Experimental results demonstrate that the proposed model achieves better performance on a challenging dataset (ETIS) compared to existing methods that rely only on convolutional neural networks, transformers, or a combination of both. The mDice and mIou indicators increased by 2.74% and 3.3% respectively. 展开更多
关键词 Medical Image Segmentation Advanced Transformer Deep Supervision Attention Mechanism
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Immune regulation of the gut-brain axis and lung-brain axis involved in ischemic stroke 被引量:1
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作者 Xiaodi Xie lei wang +2 位作者 Shanshan Dong ShanChun Ge Ting Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期519-528,共10页
Local ischemia often causes a series of inflammatory reactions when both brain immune cells and the peripheral immune response are activated.In the human body,the gut and lung are regarded as the key reactional target... Local ischemia often causes a series of inflammatory reactions when both brain immune cells and the peripheral immune response are activated.In the human body,the gut and lung are regarded as the key reactional targets that are initiated by brain ischemic attacks.Mucosal microorganisms play an important role in immune regulation and metabolism and affect blood-brain barrier permeability.In addition to the relationship between peripheral organs and central areas and the intestine and lung also interact among each other.Here,we review the molecular and cellular immune mechanisms involved in the pathways of inflammation across the gut-brain axis and lung-brain axis.We found that abnormal intestinal flora,the intestinal microenvironment,lung infection,chronic diseases,and mechanical ventilation can worsen the outcome of ischemic stroke.This review also introduces the influence of the brain on the gut and lungs after stroke,highlighting the bidirectional feedback effect among the gut,lungs,and brain. 展开更多
关键词 enteric glia cells gut microbiota gut-brain axis immune response inflammation ischemic stroke lung-brain axis microglia
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The interaction between temperature and precipitation on the potential distribution range of Betula ermanii in the alpine treeline ecotone on the Changbai Mountain
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作者 Yu Cong Yongfeng Gu +8 位作者 Wen J.wang lei wang Zhenshan Xue Yingyi Chen Yinghua Jin Jiawei Xu Mai-He Li Hong S.He Ming Jiang 《Forest Ecosystems》 SCIE CSCD 2024年第1期42-51,共10页
Alpine treeline ecotones are highly sensitive to climate warming.The low temperature-determined alpine treeline is expected to shift upwards in response to global warming.However,little is known about how temperature ... Alpine treeline ecotones are highly sensitive to climate warming.The low temperature-determined alpine treeline is expected to shift upwards in response to global warming.However,little is known about how temperature interacts with other important factors to influence the distribution range of tree species within and beyond the alpine treeline ecotone.Hence,we used a GF-2 satellite image,along with bioclimatic and topographic variables,to develop an ensemble suitable habitat model based on the species distribution modeling algorithms in Biomod2.We investigated the distribution of suitable habitats for B.ermanii under three climate change scenarios(i.e.,low(SSP126),moderate(SSP370)and extreme(SSP585)future emission trajectories)between two consecutive time periods(i.e.,current-2055,and 2055-2085).By 2055,the potential distribution range of B.ermanii will expand under all three climate scenarios.The medium and high suitable areas will decline under SSP370 and SSP585scenarios from 2055 to 2085.Moreover,under the three climate scenarios,the uppermost altitudes of low suitable habitat will rise to 2,329 m a.s.l.,while the altitudes of medium and high suitable habitats will fall to 2,201 and2,051 m a.s.l.by 2085,respectively.Warming promotes the expansion of B.ermanii distribution range in Changbai Mountain,and this expansion will be modified by precipitation as climate warming continues.This interaction between temperature and precipitation plays a significant role in shaping the potential distribution range of B.ermanii in the alpine treeline ecotone.This study reveals the link between environmental factors,habitat distribution,and species distribution in the alpine treeline ecotone,providing valuable insights into the impacts of climate change on high-elevation vegetation,and contributing to mountain biodiversity conservation and sustainable development. 展开更多
关键词 Biomod2 BIRCH Climate change Climate scenarios Habitat suitability Range shift Treeline species
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PAL-BERT:An Improved Question Answering Model
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作者 Wenfeng Zheng Siyu Lu +3 位作者 Zhuohang Cai Ruiyang wang lei wang Lirong Yin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2729-2745,共17页
In the field of natural language processing(NLP),there have been various pre-training language models in recent years,with question answering systems gaining significant attention.However,as algorithms,data,and comput... In the field of natural language processing(NLP),there have been various pre-training language models in recent years,with question answering systems gaining significant attention.However,as algorithms,data,and computing power advance,the issue of increasingly larger models and a growing number of parameters has surfaced.Consequently,model training has become more costly and less efficient.To enhance the efficiency and accuracy of the training process while reducing themodel volume,this paper proposes a first-order pruningmodel PAL-BERT based on the ALBERT model according to the characteristics of question-answering(QA)system and language model.Firstly,a first-order network pruning method based on the ALBERT model is designed,and the PAL-BERT model is formed.Then,the parameter optimization strategy of the PAL-BERT model is formulated,and the Mish function was used as an activation function instead of ReLU to improve the performance.Finally,after comparison experiments with traditional deep learning models TextCNN and BiLSTM,it is confirmed that PALBERT is a pruning model compression method that can significantly reduce training time and optimize training efficiency.Compared with traditional models,PAL-BERT significantly improves the NLP task’s performance. 展开更多
关键词 PAL-BERT question answering model pretraining language models ALBERT pruning model network pruning TextCNN BiLSTM
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A nanobody-based blocking enzyme-linked immunosorbent assay for detecting antibodies against pseudorabies virus glycoprotein E
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作者 Huanhuan Lü Pinpin Ji +6 位作者 Siyu Liu Ziwei Zhang lei wang Yani Sun Baoyuan Liu Lizhen wang Qin Zhao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1354-1368,共15页
Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry worldwide.PRV glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA... Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry worldwide.PRV glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA)has been used to distinguish gE-deleted vaccine-immunized pigs from wild-type virus-infected pigs to eradicate PR in some countries.Nanobody has the advantages of small size and easy genetic engineering and has been a promising diagnostic reagent.However,there were few reports about developing nanobody-based ELISA for detecting anti-PRV-gE antibodies.In the present study,the recombinant PRV-gE was expressed with a bacterial system and used to immunize the Bactrian camel.Then,two nanobodies against PRV-gE were screened from the immunized camel by phage display technique.Subsequently,two nanobody-HRP fusion proteins were expressed with HEK293T cells.The PRV-gE-Nb36-HRP fusion protein was selected as the probe for developing the blocking ELISA(bELISA)to detect anti-PRV-gE antibodies.Through optimizing the conditions of bELISA,the amount of coated antigen was 200 ng per well,and dilutions of the fusion protein and tested pig sera were separately 1:320 and 1:5.The cut-off value of bELISA was 24.20%,and the sensitivity and specificity were 96.43 and 92.63%,respectively.By detecting 233 clinical pig sera with the developed bELISA and a commercial kit,the results showed that the coincidence rate of two assays was 93.99%.Additionallly,epitope mapping showed that PRV-gE-Nb36 recognized a conserved conformational epitope in different reference PRV strains.Simple,great stability and low-cost nanobody-based bELISA for detecting anti-PRV-gE antibodies were developed.The bELISA could be used for monitoring and eradicating PR. 展开更多
关键词 NANOBODY nanobody-HRP blocking ELISA PRV-gE ANTIBODY
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A non-probabilistic reliability topology optimization method based on aggregation function and matrix multiplication considering buckling response constraints
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作者 lei wang Yingge LIU +2 位作者 Juxi HU Weimin CHEN Bing HAN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第2期321-336,共16页
A non-probabilistic reliability topology optimization method is proposed based on the aggregation function and matrix multiplication.The expression of the geometric stiffness matrix is derived,the finite element linea... A non-probabilistic reliability topology optimization method is proposed based on the aggregation function and matrix multiplication.The expression of the geometric stiffness matrix is derived,the finite element linear buckling analysis is conducted,and the sensitivity solution of the linear buckling factor is achieved.For a specific problem in linear buckling topology optimization,a Heaviside projection function based on the exponential smooth growth is developed to eliminate the gray cells.The aggregation function method is used to consider the high-order eigenvalues,so as to obtain continuous sensitivity information and refined structural design.With cyclic matrix programming,a fast topology optimization method that can be used to efficiently obtain the unit assembly and sensitivity solution is conducted.To maximize the buckling load,under the constraint of the given buckling load,two types of topological optimization columns are constructed.The variable density method is used to achieve the topology optimization solution along with the moving asymptote optimization algorithm.The vertex method and the matching point method are used to carry out an uncertainty propagation analysis,and the non-probability reliability topology optimization method considering buckling responses is developed based on the transformation of non-probability reliability indices based on the characteristic distance.Finally,the differences in the structural topology optimization under different reliability degrees are illustrated by examples. 展开更多
关键词 BUCKLING topology optimization aggregation function uncertainty propagation analysis non-probabilistic reliability
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Stable multi-electron reaction stimulated by W doping VS_(4)for enhancing magnesium storage performance
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作者 Yuxin Tian Jiankang Chen +7 位作者 Guofeng wang Bing Sun Alan Meng lei wang Guicun Li Jianfeng Huang Shiqi Ding Zhenjiang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期89-98,I0004,共11页
Rechargeable magnesium batteries(RMBs)hold promise for offering higher volumetric energy density and safety features,attracting increasing research interest as the next post lithium-ion batteries.Developing high perfo... Rechargeable magnesium batteries(RMBs)hold promise for offering higher volumetric energy density and safety features,attracting increasing research interest as the next post lithium-ion batteries.Developing high performance cathode material by inducing multi-electron reaction process as well as maintaining structural stability is the key to the development and application of RMBs.Herein,multielectron reaction occurred in VS_(4)by simple W doping strategy.W doping induces valence of partial V as V^(2+)and V^(3+)in VS_(4)structure,and then stimulates electrochemical reaction involving multi-electrons in 0.5%W-V-S.The flower-like microsphere morphology as well as rich S vacancies is also modulated by W doping to neutralize structure change in such multi-electron reaction process.The fabricated 0.5%W-V-S delivers higher specific capacity(149.3 m A h g^(-1)at 50 m A g^(-1),which is 1.6 times higher than that of VS_(4)),superior rate capability(76 mA h g^(-1)at 1000 mA g^(-1)),and stable cycling performance(1500cycles with capacity retention ratio of 93.8%).Besides that,pesudocapaticance-like contribution analysis as well as galvanostatic intermittent titration technique(GITT)further confirms the enhanced Mg^(2+)storage kinetics during such multi-electron involved electrochemical reaction process.Such discovery provides new insights into the designing of multi-electron reaction process in cathode as well as neutralizing structural change during such reaction for realizing superior electrochemical performance in energy storage devices. 展开更多
关键词 Multi-electron reaction W doping Stable structure CATHODE Rechargeable magnesium batteries
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A study of the soil water potential threshold values to trigger irrigation of ‘Shimizu Hakuto’ peach at pivotal fruit developmental stages
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作者 Yusui Lou Yuepeng Han +4 位作者 Yubin Miao Hongquan Shang Zhongwei Lv lei wang Shiping wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期376-386,共11页
Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established man... Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established manly based on the effects of water deficits on final fruit quality.Few studies have focused on the real-time effects of water status on fruit and shoot growth.To establish soil water potential (ψ_(soil)) thresholds to trigger irrigation of peach at pivotal fruit developmental stages,photogrammetry,^(13)C labelling,and other techniques were used in this study to investigate real-time changes in stem diameter,fruit projected area,net leaf photosynthetic rate (P_(n)),and allocation of photoassimilates to fruit under soil water potential conditions ranging from saturation to stress in 6-year-old Shimizu hakuto’peach.Stem growth,fruit growth,and P_n exhibited gradually decreasing sensitivity to water deficits during fruit developmental stages I,II,and III.Stem diameter growth was significantly inhibited whenψ_(soil)dropped to-8.5,-7.6,and-5.4 k Pa,respectively.Fruit growth rate was low,reaching zero when theψ_(soil)was-9.0 to-23.1,-14.9 to-21.4,and-16.5 to-23.3 k Pa,respectively,and P_ndecreased significantly when theψ_(soil)reached-24.2,-22.7,and-20.4 kPa,respectively.In addition,more photoassimilates were allocated to fruit under moderateψ_(soil)conditions (-10.1 to-17.0 k Pa) than under otherψ_(soil)values.Our results revealed threeψ_(soil)thresholds,-10.0,-15.0,and-15.0 kPa,suitable for triggering irrigation during stages I,II,and III,respectively.These thresholds can be helpful for controlling excessive tree vigor,maintaining rapid fruit growth and leaf photosynthesis,and promoting the allocation of more photoassimilates to fruit. 展开更多
关键词 PEACH Soil water potential Irrigation threshold Fruit expansion PHOTOSYNTHESIS
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Effectively modulating spatial vortex four-wave mixing in a diamond atomic system
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作者 巴诺 姜明奇 +4 位作者 费金友 王丹 蒋海林 王磊 王海华 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期473-478,共6页
Due to the spatial characteristics of orbital angular momentum,vortex fields can be applied in the fields of quantum storage and quantum information.We study the realization of spatially modulated vortex fields based ... Due to the spatial characteristics of orbital angular momentum,vortex fields can be applied in the fields of quantum storage and quantum information.We study the realization of spatially modulated vortex fields based on four-wave mixing in a four-level atomic system with a diamond structure.The intensity and spiral phase of the vortex field are effectively transferred to the generated four-wave mixing field.By changing the detuning of the probe field,the phase and intensity of the generated vertex four-wave mixing field can be changed.When the probe field takes a large detuning value,the spatial distribution of the intensity and phase of the vertex four-wave mixing field can be effectively tuned by adjusting the Rabi frequency or detuning value of the coupled field.At the same time,we also provide a detailed explanation based on the dispersion relationship,and the results agree well with our simulation results. 展开更多
关键词 coherent optical effects four-wave mixing orbital angular momentum
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复杂任务情境中技术如何促进部门协同——基于S市市域社会治理现代化指挥中心的案例研究
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作者 王磊 王小芳 《公共行政评论》 北大核心 2024年第1期158-177,M0006,M0007,共22页
已有研究多将技术促进部门协同理解为技术与组织互动视角下,基层政府为应对复杂任务情境采取的一种策略性行为,但对其背后的权力维度关注甚少。论文围绕权力视角下技术如何实现政府部门协同这一核心问题,选取S市市域社会治理现代化指挥... 已有研究多将技术促进部门协同理解为技术与组织互动视角下,基层政府为应对复杂任务情境采取的一种策略性行为,但对其背后的权力维度关注甚少。论文围绕权力视角下技术如何实现政府部门协同这一核心问题,选取S市市域社会治理现代化指挥中心为案例,探讨技术是否影响,以及如何影响政府部门间的权力关系。研究认为,从案例中析出的分布式治理遵从了“任务情境-技术应用-治理行为”相互适配的行动逻辑,对标复杂性任务情境,通过平台技术的协调功能,能够推动政府部门围绕“高效处置一件事”组建任务共同体。这种任务共同体暗含了以“科层为体、技术为用”的嵌套性组织结构和松散耦合性部门关系互为表里的新型权力结构——分布式权力网络。分布式治理作为根植于中国城市基层治理场景的微观理论,一方面有助于丰富基层治理机制的理论图谱,对传统基层治理机制选择的理论预设以及技术治理与科层治理共生理论进行了部分修正和改进;另一方面,通过反思技术与科层组织关系的传统研究路径,将权力维度重新拉入技术与组织关系研究,在一定程度上扩展了既有研究视域。同时,分布式治理的提出也为回答“优化基层治理数字化转型和技术化创新”之问提供了一个探索性答案。 展开更多
关键词 分布式治理 分布式权力网络 横向协同 复杂任务情境 技术治理
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Individualized anti-thrombotic therapy for acute myocardial infarction complicated with left ventricular thrombus: A case report
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作者 Yan Song Hua Li +5 位作者 Xia Zhang lei wang Hong-Yan Xu Zhi-Chao Lu Xiao-Gang wang Bo Liu 《World Journal of Clinical Cases》 SCIE 2024年第4期835-841,共7页
BACKGROUND Presently,there is no established standard anti-blood clot therapy for patients facing acute myocardial infarction(AMI)complicated by left ventricular thrombus(LVT).While vitamin K antagonists are the prefe... BACKGROUND Presently,there is no established standard anti-blood clot therapy for patients facing acute myocardial infarction(AMI)complicated by left ventricular thrombus(LVT).While vitamin K antagonists are the preferred choice for oral blood thinning,determining the best course of blood-thinning medication remains challenging.It is unclear if non-vitamin K antagonist oral blood thinners have different effectiveness in treating LVT.This study significantly contributes to the medical community.CASE SUMMARY The blood-thinning treatment of a patient with AMI and LVT was analyzed.Triple blood-thinning therapy included daily enteric-coated aspirin tablets at 0.1 g,daily clopidogrel hydrogen sulfate at 75 mg,and dabigatran etexilate at 110 mg twice daily.After 15 d,the patient’s LVT did not decrease but instead increased.Clinical pharmacists comprehensively analyzed the cases from the perspective of the patient’s disease status and drug interaction.The drug regimen was reformulated for the patient,replacing dabigatran etexilate with warfarin,and was administered for six months.The clinical pharmacist provided the patient with professional and standardized pharmaceutical services.The patient’s condition was discharged after meeting the international normalized ratio value(2-3)criteria.The patient fully complied with the follow-up,and the time in the therapeutic range was 78.57%,with no serious adverse effects during pharmaceutical monitoring.CONCLUSION Warfarin proves to be an effective drug for patients with AMI complicated by LVT,and its blood-thinning course lasts for six months. 展开更多
关键词 Myocardial infarction Left ventricular thrombus Dabigatran etexilate WARFARIN Clinical pharmacist Case report
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Intelligent Small Sample Defect Detection of Concrete Surface Using Novel Deep Learning Integrating Improved YOLOv5
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作者 Yongming Han lei wang +1 位作者 Youqing wang Zhiqiang Geng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期545-547,共3页
Dear Editor,This letter presents an intelligent small sample defect detection of concrete surface using novel deep learning integrating the improved YOLOv5 based on the Wasserstein GAN(WGAN)enhancement algorithm.The p... Dear Editor,This letter presents an intelligent small sample defect detection of concrete surface using novel deep learning integrating the improved YOLOv5 based on the Wasserstein GAN(WGAN)enhancement algorithm.The proposed method is capable of producing top-notch data sets to address the issues of insufficient samples and substandard quality. 展开更多
关键词 CONCRETE integrating ALGORITHM
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6G New Multiple Access Technology
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作者 Yifei Yuan Yongpeng Wu +3 位作者 lei wang Zhifeng Yuan Wei Bai Yuanwei Liu 《China Communications》 SCIE CSCD 2024年第1期I0002-I0005,共4页
As a basic technology at physical layer of mobile communications,non-orthogonal multiple access has been attracting wide attention across the academia and the industry.During the standardization of the fifth-generatio... As a basic technology at physical layer of mobile communications,non-orthogonal multiple access has been attracting wide attention across the academia and the industry.During the standardization of the fifth-generation(5G)of mobile communications,3GPP conducted preliminary study on non-orthogonal multiple access without reaching the consensus to standardize the technology. 展开更多
关键词 TECHNOLOGY ACCESS attracting
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Early embryonic failure caused by a novel mutation in the TUBB8 gene:A case report
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作者 Xiao-Yu Zhang Xing-Xing Zhang lei wang 《World Journal of Clinical Cases》 SCIE 2024年第12期2092-2098,共7页
BACKGROUND This study aimed to explore the relationship between gene mutations and early embryonic development arrest and to provide more possibilities for the diagnosis and treatment of repeated implantation failure.... BACKGROUND This study aimed to explore the relationship between gene mutations and early embryonic development arrest and to provide more possibilities for the diagnosis and treatment of repeated implantation failure.CASE SUMMARY Here,we collected and described the clinical data of a patient with early embryonic development stagnation after repeated in vitro fertilization attempts for primary infertility at the Department Reproductive Center of Zaozhuang Maternal and Child Healthcare Hospital.We also detected the whole-exon gene of the patient's spouse and parents,and conducted bioinformatics analysis to determine the pathogenesis of the gene.CONCLUSION A novel mutant of the TUBB8 gene[c.602G>T(p.C201F)]was identified,and this mutant provided new data on the genotype-phenotype relationships of related diseases. 展开更多
关键词 GENES MUTATION Embryonic development Fertilization in vitro Intracytoplasmic sperm injection Case report
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Pectolinarin inhibited LPS-stimulated inflammation in microglial BV_(2) cells via NF-κB signaling pathway
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作者 Bin-Feng Cheng Xiao Feng +8 位作者 Yu-Qian Dong Shao-Qin Jian Hao-Heng Yu Jing-Jing Li Ting Ma Jun Zhang Yao-Dong Zhang Hai-Jie Yang lei wang 《Traditional Medicine Research》 2024年第6期12-18,共7页
Background:Neuro-inflammation is regarded as one of the critical pathogenesis in neurodegenerative diseases,which is characterized by the activated microglial cells.Pectolinarin(Pec),a natural flavonoid that exists in... Background:Neuro-inflammation is regarded as one of the critical pathogenesis in neurodegenerative diseases,which is characterized by the activated microglial cells.Pectolinarin(Pec),a natural flavonoid that exists in many Chinese herbal medicines,has been reported to have various biological activities.However,the effects and mechanisms on neuro-inflammation are not clear.Methods:In this study,the inhibitory effects and mechanisms of Pec on neuro-inflammation were investigated in the LPS-stimulated microglial BV_(2) cells.BV_(2) microglial cells were treated with Pec or vehicle,followed by LPS.Enzyme-linked immunosorbent assay,real-time quantitative PCR,nitric oxide and reactive oxygen species assay,and western blot were performed to examine the effects of Pec on neuro-inflammatory responses.Results:We showed that Pec significantly inhibited the expression of tumor necrosis factorαand interleukin 6 in mRNA and protein levels induced by LPS.Moreover,the production of nitric oxide,iNOS,reactive oxygen species,and COX-2 were suppressed by Pec in LPS-stimulated microglial BV_(2) cells.In addition,Pec inhibited LPS-induced inflammation via nuclear factor kappa B signaling pathway,as evidenced by the reduction of the phosphorylation of inhibitor of nuclear factor kappa-B kinase,the degradation of IκBα,and the nuclear translocation of p65.Conclusion:Taken together,Pec exhibited anti-inflammatory effects in LPS-stimulated microglial BV_(2) cells via nuclear factor kappa B signaling pathway,which might provide therapeutic potential for neuro-inflammation and neurodegenerative diseases. 展开更多
关键词 NEUROINFLAMMATION microglial cells pectolinarin NF-κB
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Research Progress on Detection Techniques of Fungicide Residues in Chinese Chives
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作者 Xiuying CHEN Zhe MENG +5 位作者 Chen DING Huihui LIU Yancheng ZHOU Jinlu LI Yanhua YAN lei wang 《Agricultural Biotechnology》 2024年第1期43-48,共6页
Chinese chive is a kind of medicinal and edible plant,with many diseases,and chemical fungicides are usually used for control.In order to find out the risk of pesticide residues in Chinese chives,this paper summarized... Chinese chive is a kind of medicinal and edible plant,with many diseases,and chemical fungicides are usually used for control.In order to find out the risk of pesticide residues in Chinese chives,this paper summarized relevant literatures published in recent years,and sorted out and analyzed the types of pesticides used and detection techniques of common diseases in Chinese chives. 展开更多
关键词 Chinese chive Pesticide residues FUNGICIDE Detection technique
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Oxidative Esterification of Methacrolein to Methyl Methacrylate over Supported Palladium Catalyst 被引量:3
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作者 Wei ZHAO Wei Guo CHENG +3 位作者 Zeng Xi LI lei wang Xiang Ping ZHANG Suo Jiang ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期739-742,共4页
Supported palladium catalysts, which were used in the oxidative esterification of methacrolein to methyl methacrylate, have been prepared with different carriers and Pd precursors. Experimental results revealed that P... Supported palladium catalysts, which were used in the oxidative esterification of methacrolein to methyl methacrylate, have been prepared with different carriers and Pd precursors. Experimental results revealed that Pd catalysts with γ-Al2O3 support and Na2PdCl4 precursor showed good performance. Pd catalyst modified with Pb and Mg indicated that Pd-Mg bimetallic catalyst exhibited considerably higher activity and Pd-Pb exhibited both higher activity and selectivity. 92.27% methacrolein conversion and 90.57% methyl methacrylate selectivity were obtained on Pd-Pb-Mg catalyst. 展开更多
关键词 氧化酯化作用 异丁烯醛 甲基甲基丙烯酸酯 钯催化剂 氧化铝
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超声提取-高效液相色谱法测定化妆品中5种苯并三唑类紫外线吸收剂 被引量:1
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作者 王磊 吴越 田冬 《日用化学工业(中英文)》 CAS 北大核心 2023年第1期109-114,共6页
建立了一种利用高效液相色谱同时测定化妆品中甲酚曲唑(UV-P)、奥克三唑(UV-329)、布美三唑(UV-326)、甲酚曲唑三硅氧烷(DTTSO)、亚甲基双-苯并三唑基四甲基丁基酚(UV-360)的方法。其中,水状化妆品经甲醇/四氢呋喃溶解、超声提取、微孔... 建立了一种利用高效液相色谱同时测定化妆品中甲酚曲唑(UV-P)、奥克三唑(UV-329)、布美三唑(UV-326)、甲酚曲唑三硅氧烷(DTTSO)、亚甲基双-苯并三唑基四甲基丁基酚(UV-360)的方法。其中,水状化妆品经甲醇/四氢呋喃溶解、超声提取、微孔滤膜过滤后进样;乳液状、霜状化妆品经甲醇/四氢呋喃溶解、涡旋振荡、超声提取、微孔滤膜过滤后进样。使用ZORBAX SC-C18色谱柱(250 mm×4.6 mm,5μm),柱温23℃,以0.1%的甲酸水溶液为A相、甲醇为B相、四氢呋喃为C相进行洗脱,流速1.0 mL/min,检测波长340 nm,进样量5μL。结果表明,5种紫外线吸收剂在11~176 mg/L的质量浓度范围内线性关系良好(R2≧0.9994),检测限分别为6.72,11.94,13.80,18.47和23.49μg/L,相对标准偏差小于1.7%(n=6),加标平均回收率达到93.7%~104.5%。该方法能满足化妆品中5种苯并三唑类紫外线吸收剂的测定。 展开更多
关键词 超声提取 高效液相色谱 化妆品 苯并三唑 防晒剂 紫外线吸收剂
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外泌体相关作用因子在结直肠癌诊治中的研究进展
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作者 王白燕 卫耀斌 +3 位作者 杨艺 王磊 董然然(综述) 冯书营(审校) 《中国肿瘤临床》 CAS CSCD 北大核心 2023年第12期643-648,共6页
结直肠癌是最常见的消化系统恶性肿瘤之一,且近年来呈现上升和年轻态趋势。针对结直肠癌的治疗,除传统的手术、放疗、化疗等手段外,免疫治疗和靶向治疗已成为当前临床的研究热点,其中肿瘤源性外泌体在结直肠癌诊治过程中的优势逐渐凸显... 结直肠癌是最常见的消化系统恶性肿瘤之一,且近年来呈现上升和年轻态趋势。针对结直肠癌的治疗,除传统的手术、放疗、化疗等手段外,免疫治疗和靶向治疗已成为当前临床的研究热点,其中肿瘤源性外泌体在结直肠癌诊治过程中的优势逐渐凸显,参与了肿瘤的发生发展、侵袭和转移过程,可作为结直肠癌的诊断标志物、细胞间信息媒介和药物载体,在结直肠癌的免疫治疗和靶向治疗中发挥重要作用。但外泌体(exosome,Exo)在临床应用中还面临着诸多挑战和问题。本文将对Exo在结直肠癌诊治过程中相关因子的作用,包括作为生物标志物、载体功能、介导耐药、免疫调节、促血管生成等功能进行系统性综述,使其更好应用于结直肠癌的早期诊断、治疗和预后监测等,也为其他肿瘤的诊治提供借鉴。 展开更多
关键词 结直肠癌 外泌体 相关因子 标志物 纳米载体
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“读书无用”还是“知识改变命运”?——教育对代际流动的影响及其认知偏差研究
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作者 吴本健 王蕾 罗玲 《教育与经济》 北大核心 2023年第6期39-49,共11页
究竟是“读书无用”还是“知识改变命运”,该话题一直受社会各界共同关注。本文基于覆盖31个省(直辖市、自治区)的6轮CGSS微观调查数据,采用多项Logit模型,从主观和客观的双重视角出发,实证分析了教育与代际流动及其认知偏差之间的关系... 究竟是“读书无用”还是“知识改变命运”,该话题一直受社会各界共同关注。本文基于覆盖31个省(直辖市、自治区)的6轮CGSS微观调查数据,采用多项Logit模型,从主观和客观的双重视角出发,实证分析了教育与代际流动及其认知偏差之间的关系。研究发现:(1)随着受教育年限的提高,个体对于教育对代际流动影响的认知将产生偏差,即主观上看似“读书无用”,实则“知识改变命运”;(2)主观上,教育会通过激发个体的物质渴求,进而抑制代际向上流动;(3)客观上,教育会通过提升个体的配置能力,进而促进代际向上流动;(4)教育对代际流动的影响存在性别差异和户籍差异,即存在群体间的机会不均等。据此,为了更好地发挥教育促进代际流动的重要作用,一方面,要构建规则更加透明、机会更加公平的现代教育体系;另一方面,要营造积极良好的社会氛围,缓解个体对代际流动认知向下偏移所带来的负面影响。与此同时,要进一步打破劳动力市场存在的多种壁垒和隐形歧视,切实保障女性和农村流动人口实现公平就业。 展开更多
关键词 教育 代际流动 认知偏差 物质渴求 配置能力
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