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Two-photon live imaging of direct glia-to-neuron conversion in the mouse cortex
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作者 Zongqin Xiang Shu He +13 位作者 Rongjie Chen Shanggong liu Minhui liu liang Xu Jiajun Zheng Zhouquan Jiang Long Ma Ying Sun Yongpeng Qin Yi Chen wen li Xiangyu Wang Gong Chen wenliang Lei 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1781-1788,共8页
Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for ... Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction. 展开更多
关键词 astrocyte-to-neuron conversion Ca2+imaging direct lineage conversion GLIA ASTROCYTE in vivo reprogramming lineage-tracing mice NeuroD1 NEURON two-photon imaging
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Isolation and bioactivity screening of soy isoflavones from soybean glycolipids identifies daidzin as a promising anti-inflammatory agent
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作者 Xiao-Chuan Fang Xue-Mei He +8 位作者 Yuan-Ru Zheng wen li Tang-Jia Yang Jing-Tao Yu Jun-Le li Zi-Zhe Cai Yong Wang lin-Zhong Yu Jun-Shan liu 《Traditional Medicine Research》 2024年第3期1-9,共9页
Background:Soybean has long been utilized in the realm of traditional Chinese medicine.One of its extracts,soybean glycolipids,serves as a vital by-product of soybean oil refining,but its chemical composition and phar... Background:Soybean has long been utilized in the realm of traditional Chinese medicine.One of its extracts,soybean glycolipids,serves as a vital by-product of soybean oil refining,but its chemical composition and pharmacological potential have yet to be fully elucidated.Methods:In this study,the chemical components were isolated,and the inhibitory effects of these isolates were explored in different zebrafish inflammatory models by survival rate,Histological examination assay and quantitative Real-time PCR assay.The cytotoxicity of daidzin in RAW264.7 cells was evaluated by cell viability assay,and the effect of daidzin on the release of inflammatory cytokines in RAW264.7 cells was detected by enzyme linked immunosorbent assay(ELISA).Western blotting,immunofluorescence assay and alpha7 nicotinic acetylcholine receptors siRNA transfection assay were used to further explore the anti-inflammatory mechanism of daidzin.Results:Four compounds(verticilloside,soya-cerebroside I,soya-cerebroside II and daidzin)were firstly isolated from the soybean glycolipids,among which verticilloside and daidzin inhibited the lipopolysaccharide,CuSO4-and tail cut-stimulated zebrafish inflammation.Noticeably,daidzin exhibited anti-inflammatory activities by increasing the survival rate,alleviating the inflammatory cells infiltration,and down-regulating the expression of pro-inflammatory cytokines and nuclear factor kappa-B,NF-kappa-B inhibitor alpha,and signal transducer and activator of transcription3 in zebrafish.Moreover,daidzin decreased the secretion of IL-6 and TNF-α,inhibited the nuclear translocations of nuclear factor kappa-B p65 and p-signal transducer and activator of transcription3 as well as the NF-kappa-B inhibitor alpha phosphorylation at Ser32 in RAW 264.7 cells.More importantly,it elevated the expression level of alpha7 nicotinic acetylcholine receptors in both zebrafish and RAW 264.7 cells,and the inhibitory effect of daidzin was attenuated after the addition of alpha7 nicotinic acetylcholine receptors siRNA.Conclusion:Our study revealed that daidzin inhibited inflammation by activating the cholinergic anti-inflammatory pathway and further inhibiting the nuclear factor kappa-B and signal transducer and activator of transcription3 signaling.At the same time,it also promotes the recycling of crude soybean glycolipids and supports the potential use of daidzin as a functional food or natural dietary anti-inflammatory agent. 展开更多
关键词 SOYBEAN DAIDZIN ANTI-INFLAMMATION ZEBRAFISH α7nAchR
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Exendin-4 and linagliptin attenuate neuroinflammation in a mouse model of Parkinson's disease 被引量:6
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作者 Hai-Yang Yu Tong Sun +7 位作者 Zhen Wang Hong li Duo Xu Jing An Lu-Lu wen Jia-Yi li wen li Juan Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第8期1818-1826,共9页
Use of glucagon-like peptide-1 receptor agonist or dipeptidyl peptidase 4 inhibitor has been shown to lower the incidence of Parkinson's disease in patients with diabetes mellitus.Therefore,using these two treatme... Use of glucagon-like peptide-1 receptor agonist or dipeptidyl peptidase 4 inhibitor has been shown to lower the incidence of Parkinson's disease in patients with diabetes mellitus.Therefore,using these two treatments may help treat Parkinson's disease.To further investigate the mechanisms of action of these two compounds,we established a model of Parkinson's disease by treating mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and then subcutaneously injected them with the glucagon-like peptide-1 receptor agonist exendin-4 or the dipeptidyl peptidase 4 inhibitor linagliptin.We found that both exendin-4 and linagliptin reversed motor dysfunction,glial activation,and dopaminergic neuronal death in this model.In addition,both exendin-4 and linagliptin induced microglial polarization to the anti-inflammatory M2 phenotype and reduced pro-inflammatory cytokine secretion.Moreover,in vitro experiments showed that treatment with exendin-4 and linagliptin inhibited activation of the nucleotide-binding oligomerization domain-and leucine-rich-repeat-and pyrin-domaincontaining 3/caspase-1/interleukin-1βpathway and subsequent pyroptosis by decreasing the production of reactive oxygen species.These findings suggest that exendin-4 and linagliptin exert neuroprotective effects by attenuating neuroinflammation through regulation of microglial polarization and the nucleotidebinding oligomerization domain-and leucine-rich-repeat-and pyrin-domain-containing 3/caspase-1/interleukin-1βpathway in a mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.Therefore,these two drugs may serve as novel anti-inflammatory treatments for Parkinson's disease. 展开更多
关键词 diabetes mellitus dipeptidyl peptidase 4 inhibitor EXENDIN-4 glucagon-like peptide-1 receptor agonist 1-methyl-4-phenyl-1 2 3 6-TETRAHYDROPYRIDINE LINAGLIPTIN microglia NEUROINFLAMMATION NLRP3 inflammasome Parkinson's disease PYROPTOSIS
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Effect of cooked rice with added fructo-oligosaccharide on faecal microorganisms investigated by in vitro digestion and fermentation 被引量:2
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作者 Fei Pei wen li +5 位作者 Xiaolei Ni Xinyang Sun Yijun Yao Yong Fang wenjian Yang Qiuhui Hu 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期662-668,共7页
In the present study,the effects of cooked rice(CR)with added fructo-oligosaccharide(FOS)on faecal flora were studied by a simulated in vitro digestion and fermentation method.The total carbohydrate content,p H,and s ... In the present study,the effects of cooked rice(CR)with added fructo-oligosaccharide(FOS)on faecal flora were studied by a simulated in vitro digestion and fermentation method.The total carbohydrate content,p H,and s hort-chain fatty acids(SCFAs)were determined during in vitro digestion and fermentation.The change in the bacterial phase distribution after the fermentation was also analysed.The results showed that t he total carbohydrate content of the CR with added FOS(FCR)significantly decreased during the simulated digestion.Meanwhile,the p H of the FCR decreased and the SCFAs concentration increased significantly compared to those of the CR during the simulated fermentation.In addition,the FCR showed the advantage of promoting beneficial bacteria,such as Bifidobacterium and Lactobacillus,and inhibiting harmful bacteria,such as Bacteroides and Klebsiella compared to the CR.Therefore,the FOS as a prebiotic could be recommended to produce the high-quality healthy rice food. 展开更多
关键词 FRUCTO-OLIGOSACCHARIDE In vitro FERMENTATION Rice Short-chain fatty acids Bacterial phase distribution
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Probabilistic time series forecasting with deep non-linear state space models 被引量:1
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作者 Heming Du Shouguo Du wen li 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期3-13,共11页
Probabilistic time series forecasting aims at estimating future probabilistic distributions based on given time series observations.It is a widespread challenge in various tasks,such as risk management and decision ma... Probabilistic time series forecasting aims at estimating future probabilistic distributions based on given time series observations.It is a widespread challenge in various tasks,such as risk management and decision making.To investigate temporal patterns in time series data and predict subsequent probabilities,the state space model(SSM)provides a general framework.Variants of SSM achieve considerable success in many fields,such as engineering and statistics.However,since underlying processes in real-world scenarios are usually unknown and complicated,actual time series observations are always irregular and noisy.Therefore,it is very difficult to determinate an SSM for classical statistical approaches.In this paper,a general time series forecasting framework,called Deep Nonlinear State Space Model(DNLSSM),is proposed to predict the probabilistic distribution based on estimated underlying unknown processes from historical time series data.We fuse deep neural networks and statistical methods to iteratively estimate states and network parameters and thus exploit intricate temporal patterns of time series data.In particular,the unscented Kalman filter(UKF)is adopted to calculate marginal likelihoods and update distributions recursively for non-linear functions.After that,a non-linear Joseph form covariance update is developed to ensure that calculated covariance matrices in UKF updates are symmetric and positive definitive.Therefore,the authors enhance the tolerance of UKF to round-off errors and manage to combine UKF and deep neural networks.In this manner,the DNLSSM effectively models non-linear correlations between observed time series data and underlying dynamic processes.Experiments in both synthetic and real-world datasets demonstrate that the DNLSSM consistently improves the accuracy of probability forecasts compared to the baseline methods. 展开更多
关键词 Artificial Intelligence machine learning time series
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最优尺寸参数对涡流管能量分离效应影响的研究
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作者 文力 李浩 +2 位作者 岳慧峰 金旭 张宇 《低温工程》 CAS CSCD 北大核心 2024年第2期22-27,85,共7页
为确定出涡流管各因素的主次顺序,找出最优的参数组合,提出正交试验设计和极差分析法,找到涡流管能量分离效应的最优化尺寸参数。实验设定涡流管进气温度为26℃,环境温度为27.1℃,结果表明,4个尺寸参数对涡流管能量分离影响排序为:长径... 为确定出涡流管各因素的主次顺序,找出最优的参数组合,提出正交试验设计和极差分析法,找到涡流管能量分离效应的最优化尺寸参数。实验设定涡流管进气温度为26℃,环境温度为27.1℃,结果表明,4个尺寸参数对涡流管能量分离影响排序为:长径比>喷嘴数目>冷端直径>进气压力,每个参数的最优值各为长径比为25.0、喷嘴个数为6、冷端直径为5 mm、进气压力为0.8 MPa,并通过对试验结果的验证,发现涡流管的冷热端出口温差为95.2℃。根据正交试验设计方案找出了涡流管各部件的最优尺寸参数。 展开更多
关键词 涡流管 能量分离 尺寸参数 正交试验 最优组合
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Liraglutide Suppresses Myocardial Fibrosis Progression by Inhibiting the Smad Signaling Pathway
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作者 wen SUN Hong MI +2 位作者 De-ying HE wen li Yi-yan SONGYANG 《Current Medical Science》 SCIE CAS 2023年第5期955-960,共6页
Objective Liraglutide is a commonly used hypoglycemic agent in clinical practice,and has been demonstrated to have protective effects against the development of cardiovascular disease.However,its potential role in myo... Objective Liraglutide is a commonly used hypoglycemic agent in clinical practice,and has been demonstrated to have protective effects against the development of cardiovascular disease.However,its potential role in myocardial fibrosis remains unexplored.The present study aims to assess the impact of liraglutide on the activation of cardiac fibroblasts.Methods Primary rat adult fibroblasts were isolated,cultured,and randomly allocated into 4 groups:control group,transforming growth factor beta1(TGFβ1)stimulation group,liraglutide group,and TGFβ1+liraglutide group.Fibroblast activation was induced by TGFβ1.Cell proliferation activity was assessed using the CKK-8 kit,and cellular activity was determined using the MTT kit.Reverse transcrition-quantitative polymerase chain reaction(RT-qPCR)was utilized to quantify the level of collagen transcription,immunofluorescence staining was performed to detect the expression level of type III collagen andα-smooth muscle protein(α-SMA),and immunoblotting was conducted to monitor alterations in signal pathways.Results The addition of 10,25,50 and 100 nmol/L of liraglutide did not induce any significant impact on the viability of fibroblasts(P>0.05).The rate of cellular proliferation was significantly higher in the TGFβl stimulation group than in the control group.However,the treatment with 50 and 100 nmol/L of liraglutide resulted in the reduction of TGFβl-induced cell proliferation(P<0.05).The RT-qPCR results revealed that the transcription levels of type I collagen,type III collagen,andα-SMA were significantly upregulated in the TGFβl stimulation group,when compared to the control group(P<0.05).However,the expression levels of these aforementioned factors significantly decreased in the TGFβl+liraglutide group(P<0.05).The immunofluorescence staining results revealed a significant increase in the expression levels of type III collagen andα-SMA in the TGFβl stimulation group,when compared to the control group(P<0.05).However,these expression levels significantly decreased in the TGFβl+liraglutide group,when compared to the TGFβl stimulation group(P<0.05).The Western blotting results revealed that the expression levels of phosphorylated smad2 and smad3 significantly increased in the TGFβl stimulation group,when compared to the control group(P<0.05),while these decreased in the TGFβl+liraglutide group(P<0.05).Conclusion Liraglutide inhibits myocardial fibrosis development by suppressing the smad signaling pathway,reducing the activation and secretion of cardiac fibroblasts. 展开更多
关键词 LIRAGLUTIDE myocardial fibrosis TGFβl SMAD
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Influence of hypoxia on retinal progenitor and ganglion cells in human induced pluripotent stem cell-derived retinal organoids
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作者 Jin-lin Du li-Xiong Gao +7 位作者 Tao Wang Zi Ye Hong-Yu li wen li Quan Zeng Jia-Fei Xi wen Yue Zhao-Hui li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第10期1574-1581,共8页
AIM:To observe the effect of low oxygen concentration on the neural retina in human induced pluripotent stem cell(hiPSC)-derived retinal organoids(ROs).METHODS:The hiPSC and a three-dimensional culture method were use... AIM:To observe the effect of low oxygen concentration on the neural retina in human induced pluripotent stem cell(hiPSC)-derived retinal organoids(ROs).METHODS:The hiPSC and a three-dimensional culture method were used for the experiments.Generated embryoid bodies(EBs)were randomly and equally divided into hypoxic and normoxic groups.Photographs of the EBs were taken on days 38,45,and 52,and the corresponding volume of EBs was calculated.Simultaneously,samples were collected at these three timepoints,followed by fixation,sectioning,and immunofluorescence.RESULTS:The proportion of Ki67-positive proliferating cells increased steadily on day 38;this proliferationpromoting effect tended to increase tissue density rather than tissue volume.On days 45 and 52,the two groups had relatively similar ratios of Ki67-positive cells.Further immunofluorescence analysis showed that the ratio of SOX2-positive cells significantly increased within the neural retina on day 52(P<0.05).In contrast,the percentage of PAX6-and CHX10-positive cells significantly decreased following hypoxia treatment at all three timepoints(P<0.01),except for CHX10 at day 45(P>0.05).Moreover,the proportion of PAX6-/TUJ1+cells within the neural retinas increased considerably(P<0.01,<0.05,<0.05 respectively).CONCLUSION:Low oxygen promotes stemness and proliferation of neural retinas,suggesting that hypoxic conditions can enlarge the retinal progenitor cell pool in hiPSC-derived ROs. 展开更多
关键词 HYPOXIA retinal organoid retinal progenitor cells retinal ganglion cells
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Amplification and Bioinformatics Analysis of vscN Gene from Vibrio alginolyticus
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作者 linlin YIN wen li +4 位作者 Haiyun FENG Weijie ZHANG Junlin WANG Huanying PANG Na WANG 《Asian Agricultural Research》 2023年第5期29-33,共5页
[Objectives]The paper was to clone and analyze bioinformatics of vscN gene from Vibrio alginolyticus.[Methods]A pair of specific primers was designed based on the vscN gene sequence of V.alginolyticus HY9901.The full ... [Objectives]The paper was to clone and analyze bioinformatics of vscN gene from Vibrio alginolyticus.[Methods]A pair of specific primers was designed based on the vscN gene sequence of V.alginolyticus HY9901.The full length of vscN gene was amplified by PCR and bioinformatics analysis was performed.[Results]The vscN gene was 1323 bp in total,encoding 440 amino acids,with the theoretical molecular weight of 47.86 kD and the theoretical pI value of 5.89.The online prediction showed that there was no signal peptide and no transmembrane region in VscN.The amino acid sequence had 10 N-myristoylation sites,8 phosphorylation sites(2 protein kinase C phosphorylation sites,6 casein kinase II phosphorylation sites),1 amidation site,11 microbody C-terminal target signal sites,1 ATP/GTP binding site motif A(P ring),and 1 ATPaseαandβsubunit specific site.Homology analysis showed that the VscN protein of V.alginolyticus had high homology with that of V.antiquarius,with a similarity of 95.14%.Phylogenetic tree analysis showed that the VscN of V.alginolyticus was clustered into the same subgroup as that of V.diabolicus and V.antiquarius.Functional domain analysis of VscN protein showed that it had Pfam and AAA domains,and involved in the regulation of bacterial virulence.The three-dimensional structure model of VscN simulated by SWISS-MODEL software was similar to the structure of flagellate-specific ATPase FliH-FliI complex.[Conclusions]The results lay a foundation for further study on the regulatory mechanism of VscN protein on bacterial virulence. 展开更多
关键词 Vibrio alginolyticus T3SS VscN Bioinformatics analysis
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Exploring the potential molecular mechanism of JinlingziSan in the treatment of endometriosis based on network pharmacology system
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作者 li-Jun Zhou wen li +1 位作者 Yuan Wang Ke-Feng Sun 《Drug Combination Therapy》 2023年第2期13-20,共8页
Background:Chinese herbal medicines have been proven to be effective in clinical treatment and disease prevention.Jinlingzi San is a herbal medicine used for the treatment of endometriosis.However,a comprehensive netw... Background:Chinese herbal medicines have been proven to be effective in clinical treatment and disease prevention.Jinlingzi San is a herbal medicine used for the treatment of endometriosis.However,a comprehensive network pharmacology approach has not been used to understand the active ingredients and therapeutic mechanisms behind Jinlingzi San in the treatment of endometriosis.Methods:A network pharmacology approach and a molecular docking approach were used to predict the active ingredients and potential targets of Jinlingzi San in the treatment of endometriosis.Results:The integrated network pharmacology approach successfully identified 60 active ingredients and 540 key targets of action in Jinlingzi San dispersion.Among them,STAT3,TP53,MAPK3,RELA,MAPK1,JUN and other key genes were mainly regulated through pathways in cancer,lipid and atherosclerosis,AGE-RAGE signaling pathway in diabetic complications,pancreatic cancer,prostate cancer,PI3K-Akt signaling pathway,Th17 cell differentiation,and other signaling pathways in the cell body,receptor complexes,cytoplasm,nucleoplasm,and plasma membrane.Conclusion:Based on a systems network pharmacology approach,our work successfully predicts the active components and potential targets of Jinlingzi San for the treatment of endometriosis and helps to illustrate the mechanism of action at an integrative level.This demonstrates that Jinlingzi San for the treatment of endometriosis is regulated through a multi-component,multi-target,multi-system co-regulation.This study identifies key genes and pathways associated with endometriosis and pathogenesis from new insights,and also provides a viable approach to the chemical basis and pharmacological studies of Jinlingzi San. 展开更多
关键词 JinlingziSan network pharmacology ENDOMETRIOSIS mechanism of action
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长期不同施肥模式对大麦–双季稻田根际土壤有机氮组分的影响
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作者 郭勇 文丽 +5 位作者 石丽红 张腊梅 程凯凯 李超 郑华斌 唐海明 《土壤》 CAS CSCD 北大核心 2024年第2期273-280,共8页
根际土壤有机氮组分在土壤养分和作物氮素营养中具有重要作用。本研究依托长期(37年)定位施肥试验田,设置4个施肥处理:不施肥对照(CK)、单独施用化肥(CF)、秸秆还田+化肥(RF)和30%有机肥+70%化肥(OM),于晚稻成熟期测定大麦–双季稻田根... 根际土壤有机氮组分在土壤养分和作物氮素营养中具有重要作用。本研究依托长期(37年)定位施肥试验田,设置4个施肥处理:不施肥对照(CK)、单独施用化肥(CF)、秸秆还田+化肥(RF)和30%有机肥+70%化肥(OM),于晚稻成熟期测定大麦–双季稻田根际土壤基础理化性质、微生物生物量氮和有机氮组分(氨基酸态氮、氨基糖态氮、酸解氨态氮、酸解未知态氮、非酸解性氮)含量。研究表明:相对CK处理,RF和OM处理显著增加了稻田根际土壤有机碳、全氮、铵态氮和硝态氮的含量。RF和OM处理土壤微生物生物量氮含量分别比CK处理增加了19.8%和30.7%。酸解性氮作为根际土壤全氮的主体部分,占全氮的59.61%~72.06%;各处理根际土壤酸解性氮含量大小顺序表现为OM>RF>CF>CK。各施肥处理中,酸解有机氮中的氨基糖态氮、氨基酸态氮和酸解未知态氮含量均以OM处理最大,分别比CK处理增加139.3%、47.9%和110.0%;酸解氨态氮以RF处理最大,比CK处理增加69.9%。土壤有机碳、全氮、铵态氮、硝态氮与土壤氨基酸态氮、氨基糖态氮、酸解未知态氮以及微生物生物量氮均呈极显著(P<0.01)正相关。因此,秸秆、有机肥配施化肥均能有效提高大麦–双季稻田根际土壤的供氮能力,是改善稻田土壤肥力的有效手段。 展开更多
关键词 长期施肥 双季稻 根际土壤 有机氮组分 酸解性氮
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金属有机框架材料MIL-101在吸附去除水中有机污染物中的应用进展
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作者 兰梓溶 清江 +5 位作者 陈有为 许宙 陈茂龙 文李 程云辉 丁利 《分析测试学报》 CAS CSCD 北大核心 2024年第4期654-662,共9页
金属有机框架材料(MOFs)是一种极具前景的水中污染物吸附材料,其中,拉瓦锡研究所材料(MIL)凭借较好的稳定性和较多的可调节位点在众多MOFs中脱颖而出。与其他MILs相比,MIL-101具有比表面积较大和表面活性位点多的特点,在水中的稳定性高... 金属有机框架材料(MOFs)是一种极具前景的水中污染物吸附材料,其中,拉瓦锡研究所材料(MIL)凭借较好的稳定性和较多的可调节位点在众多MOFs中脱颖而出。与其他MILs相比,MIL-101具有比表面积较大和表面活性位点多的特点,在水中的稳定性高,已成为一种新兴的吸附材料。鉴于此,该文对近年来MIL-101在水中有机污染物去除领域的应用研究进行了综述,主要对MIL-101结构、改性修饰及其在水污染物吸附去除方面的应用及吸附机理进行了介绍。最后对MIL-101吸附材料的应用前景进行了分析和展望。 展开更多
关键词 MIL-101 吸附 改性修饰 有机污染物
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土壤-植物系统中硒的生物有效性及其影响因素研究进展
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作者 杨忠兰 翟凡 +5 位作者 温莉 颜蒙蒙 肖嬴 张永浩 姚锋先 曾希柏 《农业资源与环境学报》 CAS CSCD 北大核心 2024年第2期464-472,共9页
硒的生物有效性是决定硒在土壤-植物系统中转运、积累的关键因素,然而目前关于该方面研究进展还缺乏系统的总结和论述。本文结合赣南富硒脐橙调查研究结果,以硒在土壤-植物系统中的运移为切入点,系统总结和论述了硒在土壤-植物系统中的... 硒的生物有效性是决定硒在土壤-植物系统中转运、积累的关键因素,然而目前关于该方面研究进展还缺乏系统的总结和论述。本文结合赣南富硒脐橙调查研究结果,以硒在土壤-植物系统中的运移为切入点,系统总结和论述了硒在土壤-植物系统中的氧化-还原、吸收、转运过程,探讨了土壤理化性质、微生物、施肥、农艺管理和植物生长阶段等对硒生物有效性和迁移的影响,并提出未来硒的研究热点:土壤微生物活性与硒生物地球化学循环的耦合关系;植物生长、果实品质与硒代谢相关的分子机制;结合同位素示踪技术和薄膜扩散梯度(DGT)技术原位探究硒在生物地球化学中的归趋。本综述可为土壤硒生物有效性调控、植物体系中硒的有效积累和农艺生物强化富硒措施方面的研究提供理论参考。 展开更多
关键词 硒生物有效性 土壤-植物系统 硒转运 赣南脐橙 硒形态
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电子在自旋-轨道耦合调制下磁受限半导体纳米结构中的传输时间及其自旋极化
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作者 温丽 卢卯旺 +3 位作者 陈嘉丽 陈赛艳 曹雪丽 张安琪 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第11期377-384,共8页
通过考虑构筑在半导体GaAs/Al_(x)Ga_(1–x)As异质结上的磁受限半导体纳米结构中的塞曼效应和自旋-轨道耦合,本文采用理论分析和数值计算相结合的方法研究了电子的传输时间与自旋极化.利用矩阵对角化和改进的转移矩阵方法,数值求解电子... 通过考虑构筑在半导体GaAs/Al_(x)Ga_(1–x)As异质结上的磁受限半导体纳米结构中的塞曼效应和自旋-轨道耦合,本文采用理论分析和数值计算相结合的方法研究了电子的传输时间与自旋极化.利用矩阵对角化和改进的转移矩阵方法,数值求解电子的薛定谔方程;采用H.G.Winful理论求电子的居留时间,并计算自旋极化率.由于塞曼效应与自旋-轨道耦合,电子的居留时间明显地与其自旋有关,因此可在时间维度上分离自旋、实现半导体中电子的自旋极化.因为半导体GaAs的有效g-因子很小,电子自旋极化主要源于自旋-轨道耦合,大约为塞曼效应引起的自旋极化的4倍.由于电子的有效势与自旋-轨道耦合的强度有关,电子的居留时间及其自旋极化可通过界面限制电场或应力工程进行有效调控.这些有趣的结果不仅对半导体自旋注入具有参考价值,而且还可为半导体自旋电子学器件应用提供时间电子自旋分裂器. 展开更多
关键词 半导体自旋电子学 磁调制半导体纳米结构 自旋-轨道耦合 居留时间
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水稻穗发芽遗传与分子机制的研究进展
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作者 林鑫焱 张传忠 +5 位作者 戴兵 王馨珩 刘剑锋 温丽 徐兴健 方军 《生物技术通报》 CAS CSCD 北大核心 2024年第1期24-31,共8页
水稻穗发芽是指水稻在收获前如遇连续阴雨天气或高温潮湿环境条件,往往诱导籽粒在穗上发芽的现象。穗发芽导致水稻种子活力和品质下降,给水稻生产带来巨大损失。对于水稻抗穗发芽育种,除了扩大对穗发芽突变体的筛选外,挖掘和克隆一些控... 水稻穗发芽是指水稻在收获前如遇连续阴雨天气或高温潮湿环境条件,往往诱导籽粒在穗上发芽的现象。穗发芽导致水稻种子活力和品质下降,给水稻生产带来巨大损失。对于水稻抗穗发芽育种,除了扩大对穗发芽突变体的筛选外,挖掘和克隆一些控制穗发芽的新基因并解析其穗发芽调控机制,是水稻抗穗发芽育种的重要工作。穗发芽过程中,水稻的淀粉酶活性增强、可溶性糖含量升高,且水稻籽粒中植物激素ABA和GA的含量及二者的平衡是决定穗发芽的关键。OsVP1等一些关键基因通过ABA信号通路控制水稻种子休眠,GA则可通过激活GA相关转录因子等调控种子萌发。本文从水稻穗发芽的内部生理因素及环境条件、水稻穗发芽的遗传机制、水稻穗发芽的分子机制和水稻穗发芽的性状改良这四方面进行综述,以期阐述穗发芽的整体调控机制,为水稻抗穗发芽品种的选育提供理论参考。 展开更多
关键词 水稻 穗发芽 调控机制 性状改良
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多件台阶垫片塑胶铣工夹具结构设计
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作者 郭冉 文莉 +1 位作者 王庭江 文根保 《模具工业》 2024年第3期63-66,共4页
同时加工多件台阶垫片时,因垫片厚度的尺寸公差而厚薄不均,导致夹具不能夹紧所有工件,采用刚柔结合的夹紧方法,以偏心轮刚性夹紧机构+橡皮或塑胶柔性夹紧,使工件夹紧率达到100%。
关键词 夹具 台阶垫片 厚度偏差 柔性夹紧
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中国建筑业碳排放的分布特征及区域间影响研究
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作者 闻莉 严小丽 《工程管理学报》 2024年第2期7-12,共6页
分析了中国建筑业碳排放的时空分布特征,通过空间溢出效应,研究了中国建筑业碳排放强度在空间层面的关键影响因素,从而揭示了区域间的影响机理。结果表明:中国建筑业碳排放总量总体呈上升趋势,碳排放强度总体呈先下降后平稳趋势,并且建... 分析了中国建筑业碳排放的时空分布特征,通过空间溢出效应,研究了中国建筑业碳排放强度在空间层面的关键影响因素,从而揭示了区域间的影响机理。结果表明:中国建筑业碳排放总量总体呈上升趋势,碳排放强度总体呈先下降后平稳趋势,并且建筑业碳排放强度存在地区内趋同性和地区间的异质性;房屋建筑业占比、建筑业产业规模、地区经济水平、环境规制、建筑企业国有化率对建筑业碳排放强度具有显著的抑制作用,同时建筑业技术进步、地区经济水平和环境规制对建筑业碳排放强度具有显著的负向的空间溢出效应。据此,提出了促进建筑业碳排放有效减排的相关措施。 展开更多
关键词 碳排放 建筑业 空间溢出效应 时空特征
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一例结节性硬化症多器官受累患者的多学科诊疗
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作者 郑华 智云飞 +17 位作者 应露静 朱兰 计鸣良 梁择 王江山 石海峰 张伟宏 孝梦甦 张玉石 徐凯峰 卢朝辉 刘雅萍 徐瑞燚 朱惠娟 文礼 张炎 陈罡 陈丽萌 《罕见病研究》 2024年第1期79-86,共8页
结节性硬化症(TSC)是一种罕见的遗传性疾病,可于皮肤、脑、眼、口腔、心脏、肺脏、肾脏、肝脏和骨骼等多部位器官发生良性血管平滑肌脂肪瘤,主要表现为癫痫、智力障碍、皮肤白斑和面部血管纤维瘤等症状,发病率为1/10000~1/6000新生儿。... 结节性硬化症(TSC)是一种罕见的遗传性疾病,可于皮肤、脑、眼、口腔、心脏、肺脏、肾脏、肝脏和骨骼等多部位器官发生良性血管平滑肌脂肪瘤,主要表现为癫痫、智力障碍、皮肤白斑和面部血管纤维瘤等症状,发病率为1/10000~1/6000新生儿。本例展示了一例中年女性,以癫痫、结节样白斑起病,后期出现下腹包块、肌酐升高、重度贫血,根据临床特征和全外显子组测序明确原发病为TSC,实验室和影像学检查明确下腹包块为子宫来源,CT引导下穿刺活检病理和手术病理考虑平滑肌瘤伴脓肿。患者多器官受累,存在主线诊断之外诸多合并症,该例患者的诊治过程体现了严谨的临床思维和多学科协作在疑难罕见病诊疗过程中的重要意义。 展开更多
关键词 结节性硬化症 子宫脓肿 贫血
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CT影像组学分层鉴别三种常见孤立性肺结节的价值
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作者 牟科 范卫杰 +5 位作者 杨燕 王正明 文利 刘欢 刘浩 张冬 《陆军军医大学学报》 CAS CSCD 北大核心 2024年第6期608-617,共10页
目的 探讨基于CT影像组学特征的逻辑回归(LR)模型分层鉴别肺孤立性腺癌、结核、非结核炎性结节的价值。方法 回顾性分析2018年1月至2022年1月于陆军军医大学第二附属医院经病理证实为肺腺癌、结核、非结核炎性结节患者的临床和肺部CT资... 目的 探讨基于CT影像组学特征的逻辑回归(LR)模型分层鉴别肺孤立性腺癌、结核、非结核炎性结节的价值。方法 回顾性分析2018年1月至2022年1月于陆军军医大学第二附属医院经病理证实为肺腺癌、结核、非结核炎性结节患者的临床和肺部CT资料。通过勾画肺结节感兴趣区并提取、筛选CT影像组学特征,分别建立肺腺癌与炎性结节预测模型以及结核与非结核炎性结节预测模型。通过绘制ROC并计算AUC、灵敏度和特异度评估模型效能。结果 共收集526例孤立性肺结节,其中肺腺癌263例,结核结节99例,非结核炎性结节164例。基于CT影像组学特征和临床危险因素建立的肺腺癌与炎性结节LR预测模型在训练集中和测试集中的AUC分别为0.880、0.886。基于CT影像组学特征建立的结核与非结核炎性结节LR预测模型在训练集中和测试集中的AUC分别为0.921、0.853。结论 基于CT影像组学特征建立的LR预测模型在分层鉴别3种常见孤立性肺结节中具有较好的性能,具有较高的临床应用价值。 展开更多
关键词 肺结节 CT 影像组学 列线图 诊断
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Exploring the taste presentation and receptor perception mechanism of salty peptides from Stropharia rugosoannulata based on molecular dynamics and thermodynamics simulation
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作者 wen li Shuai Sun +6 位作者 Wanchao Chen Haile Ma Tingzhao li Zhong Zhang Di Wu Mengqiu Yan Yan Yang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2277-2288,共12页
The taste presentation and receptor perception mechanism of the salty peptide of Stropharia rugosoannulata were predicted and verified using peptide omics and molecular interaction techniques.The combination of aspart... The taste presentation and receptor perception mechanism of the salty peptide of Stropharia rugosoannulata were predicted and verified using peptide omics and molecular interaction techniques.The combination of aspartic acid(D)and glutamic acid(E),or peptide fragments composed of arginine(R),constitute the characteristic taste structural basis of salty peptides of S.rugosoannulata.The taste intensity of the salty peptide positively correlates with its concentration within a specific concentration range(0.25–1.0 mg/mL).The receptor more easily recognizes the first amino acid residue at the N-terminal of salty peptides and the aspartic acid residue in the peptides.GLU513,ASP707,and VAL508 are the critical amino acid residues for the receptor to recognize salty peptides.TRPV1 is specifically the receptor for recognizing salty peptides.Hydrogen bonds and electrostatic interactions are the main driving forces for the interactions between salty peptides and TRPV1 receptors.KSWDDFFTR has the most potent binding capacity with the receptor and has tremendous potential for application in sodium salt substitution.This study confirmed the taste receptor that specifically recognizes salty peptides,analyzed the receptor-peptide binding interaction,and provided a new idea for understanding the taste receptor perception of salty peptides. 展开更多
关键词 Salty peptide Molecular docking Biolayer interferometry Isothermal titration calorimetry
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