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Reassessing the relationship between major depressive disorder and blood lipids: a comprehensive Mendelian randomisation study
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作者 Genmin Sun Disong Xia +15 位作者 Baiqiang Xue Xuemin Jian Lixia Peng Baokun Wang Chuanhong Wu Chengwen Gao lin he Yifeng Xu Xiangzhong Zhao Qian Zhang Hui Cao Yanqin Wen Yongyong Shi James B Potash Jianhua Chen Zhiqiang Li 《General Psychiatry》 2025年第3期186-198,共13页
Background Numerous studies have consistently demonstrated that a considerable proportion of patients with major depressive disorder (MDD) frequently exhibit pronounced dyslipidaemia. However, the causal dynamics betw... Background Numerous studies have consistently demonstrated that a considerable proportion of patients with major depressive disorder (MDD) frequently exhibit pronounced dyslipidaemia. However, the causal dynamics between MDD and dyslipidaemia remain elusive.Aims To comprehensively disentangle the genetic causality between MDD and various phenotypes of blood lipids, thereby facilitating the advancement of management strategies for these conditions.Methods We conducted a two-sample univariable Mendelian randomisation (MR) analysis using different models, including the inverse variance weighted (IVW) method and causal analysis using the summary effect (CAUSE) estimates, as well as a multivariable MR analysis. This analysis used summary statistics from genome-wide association studies (GWAS) of MDD and five lipid traits: low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, total cholesterol and triglycerides (TG), encompassing 5 237 893 individuals of European and East Asian ancestries. For MDD, a total of 598 701 individuals were included, with 500 199 individuals of European ancestry (Ncase=170 756, Ncontrol=329 443) and 98 502 of East Asian ancestry (Ncase=12 588, Ncontrol=85 914). Lipid data were collected from 4 639 192 individuals through the Global Lipids Genetics Consortium (European, N=4 096 085;East Asian, N=543 107). Next, we used the two-step MR to explore the mediating factors between MDD and TG, and the risk factors affecting TG through MDD. Finally, we conducted a GWAS meta-analysis and enrichment analysis.Results In univariable MR, we observed a negative causal effect of low-density lipoprotein on MDD in both European populations (IVW: odds ratio (OR): 0.972, 95% confidence interval (CI) 0.947 to 0.998, p=0.037) and East Asian populations (IVW: OR: 0.928, 95% CI 0.864 to 0.997, p=0.042). Additionally, we identified a bidirectional causal relationship between TG and MDD, with TG having a causal effect on MDD (IVW: OR: 1.052, 95% CI 1.020 to 1.085, p=0.001) and MDD having a causal effect on TG (IVW: OR: 1.075, 95% CI 1.047 to 1.104, p<0.001). Multivariable MR analysis further supported the role of TG in MDD (OR: 1.205, 95% CI 1.034 to 1.405, p=0.017). CAUSE estimates indicated that the causal model of MDD on TG provided a better fit than the sharing model (p=0.003), while the association of TG on MDD was more likely due to horizontal correlated pleiotropy than causality. Mediation analyses revealed that waist-hip ratio (WHR) mediated 69% of the total causal effect of MDD on TG, while other identified risk factors exhibited lower mediating proportions either mediated through MDD (≤17%) or originating from MDD (≤29%). The GWAS meta-analysis highlighted potential pathways related to lipid processes and nucleosome assembling, with significant cell types identified in brain regions and liver tissues.Conclusions The findings indicate that genetic proxies of MDD are associated with elevated levels of TG, with WHR serving as a clinical indicator of the association. This suggests that interventions targeting WHR may be effective in reducing TG levels in patients with MDD. 展开更多
关键词 Mendelian Randomisation mendelian randomi Major Depressive Disorder major depressive disorder High Density Lipoprotein Cholesterol DYSLIPIDAEMIA Low Density Lipoprotein Cholesterol disentangle genetic causality
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Heterogeneous Co-based catalytic systems for alkene hydroformylation
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作者 Chao-an Liang Bo Zeng +6 位作者 Baolin Feng Huibing Shi Fengqi Zhang Jianhua Liu lin he Yuxiao Ding Chungu Xia 《Chinese Journal of Catalysis》 2025年第3期115-141,共27页
Hydroformylation of olefins is one of the highest-volume industrial reactions to meet the vast demands for aldehydes as well as their derivatives.Homogeneous Co complexes were the original catalysts industrialized sin... Hydroformylation of olefins is one of the highest-volume industrial reactions to meet the vast demands for aldehydes as well as their derivatives.Homogeneous Co complexes were the original catalysts industrialized since 1960s.Heterogeneous catalysis is considered superior owing to the facile separation of catalysts from products,shorter technical process,and reduced manufacturing costs.Unexpectedly,there has not been a single case of plant using heterogenized Co-based catalyst successfully.To address the separation issue and understand the catalytic mechanism of the reactions,this review summarizes the progress in heterogeneous systems and provides a detailed discussion of their catalytic performance.Strategies for stabilizing Co species through support modification and additive incorporation are carefully considered to elucidate why heterogeneous systems have not yet succeeded on an industrial scale.Furthermore,we provide our insights for the development of heterogeneous catalytic hydroformylation,including the challenges,opportunities,and outlooks.The aim is to deepen the fundamental understanding of heterogeneous alkene hydroformylation,guiding the community's research efforts towards realizing its successful application in the future. 展开更多
关键词 Cobalt catalysts Alkene hydroformylation Heterogeneous catalysis Aldehyde derivatives Cobalt stabilization
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Research on the refinement algorithm of surface loading deformation based on Green's function
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作者 Chenfeng Li Tengxu Zhang +3 位作者 Peibing Yang lin he Yu Xia Wei Luan 《Geodesy and Geodynamics》 2025年第2期230-239,共10页
Surface deformation calculations due to environmental loading typically rely on the Preliminary Reference Earth Model(PREM),which assumes a homogeneous and isotropic Earth structure,leading to noticeable errors.To enh... Surface deformation calculations due to environmental loading typically rely on the Preliminary Reference Earth Model(PREM),which assumes a homogeneous and isotropic Earth structure,leading to noticeable errors.To enhance accuracy,the high-precision crustal model CRUST 1.0 is used to refine calculations of regional surface deformation caused by hydrological and non-tidal atmospheric loading.The improved model is applied to 27 Global Navigation Satellite System(GNSS)reference stations in the first phase of the Crustal Movement Observation Network of China(CMONOC),considering their geographical locations.Green's functions are employed to compute surface deformation at each site.Results indicate relative discrepancies of 11.78%and 14.14%for non-tidal atmospheric and hydrological loading compared to PREM,with vertical deformation differences reaching an average of 18.95%.Additionally,the distinct spatial distribution characteristics of the relative differences in each direction indicate that the improved RPREM model is more responsive to the mass variations derived from Gravity Recovery and Climate Experiment(GRACE).The results suggest that the improved PRREM model demonstrates higher sensitivity to loading variations than the PREM model.Utilizing the enhanced method of calculating surface deformation through the utilization of Green's function at the site could effectively reduce the calculation error caused by regional structure,leading to enhanced uniformity and isotropy of PREM. 展开更多
关键词 Loading deformation GNSS Green's function PREM GRACE
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A bibliometric analysis of the relationship between the brain-derived neurotrophic factor and cognitive dysfunction due to alcohol dependence syndrome
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作者 lin he Yan Deng +3 位作者 Xin Lyu Rongzhen Cui Jie Han Le Zhang 《Journal of Translational Neuroscience》 2025年第1期30-38,共9页
Objective:To evaluate the global liter-ature output on the relationship between brain-derived neurotrophic factor(BDNF)and cognitive function in al-cohol dependence syndrome using bibliometric methods and explore the ... Objective:To evaluate the global liter-ature output on the relationship between brain-derived neurotrophic factor(BDNF)and cognitive function in al-cohol dependence syndrome using bibliometric methods and explore the status and trends in this field.Method:The literature on the application of BDNF in cognitive impairment caused by alcohol dependence syndrome published from 1995 to 2023 were retrieved from Web of Science,and the relevant information(publication characteristics,country and institution,author,number of publications,citation,journal and research field,corresponding author,key words,etc.)was recorded.The bibliometrix R package was used for quantitative and qualitative analysis of publication output and author contributions.Result:A total of 99 articles were included.The overall number of publications in this field has increased over time.The countries and institutions that contributed the most to the field were the United States and the Academy of Medical Sciences of Iranian universities,respectively.Most of the authors were from the United States,followed by Spain,China,and Iran.Ceccanti M,Fiore M were the most productive authors.Publications with Ceccanti M had the highest h-index.The most cited reference author is Haenninen H(227 citations),and the number one published journal is Alcohol.Most articles were published in 2020(n=12)and 2022(n=11),followed by 2019 and 2021(n=10).The corresponding author has the largest number of publications from the United States,and more publications from a single country tend to have more cooperation from other countries.BDNF and alcohol appeared more frequently in various keyword clouds.However,significant differences remained in the author keyword cloud,keyword plus word cloud,and paper topic word cloud.Conclusion:BDNF has great potential in the application of cognitive dysfunction caused by alcohol dependence syndrome.Bibliometric methods and data visualization techniques can help understand the current state of research progress and enable relevant scholars and practitioners to predict the development trends in this field. 展开更多
关键词 alcohol dependence syndrome cognitive impairment brain-derived neurotrophic factor bibliometric analysis
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Quantum anomalous Hall effect in twisted bilayer graphene
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作者 Wen-Xiao Wang Yi-Wen Liu lin he 《Chinese Physics B》 2025年第4期2-10,共9页
Recent advancements in two-dimensional van der Waals moir´e materials have unveiled the captivating landscape of moir´e physics.In twisted bilayer graphene(TBG)at‘magic angles’,strong electronic correlatio... Recent advancements in two-dimensional van der Waals moir´e materials have unveiled the captivating landscape of moir´e physics.In twisted bilayer graphene(TBG)at‘magic angles’,strong electronic correlations give rise to a diverse array of exotic physical phenomena,including correlated insulating states,superconductivity,magnetism,topological phases,and the quantum anomalous Hall(QAH)effect.Notably,the QAH effect demonstrates substantial promise for applications in electronic and quantum computing devices with low power consumption.This article focuses on the latest developments surrounding the QAH effect in magic-angle TBG.It provides a comprehensive analysis of magnetism and topology—two crucial factors in engineering the QAH effect within magic-angle TBG.Additionally,it offers a detailed overview of the experimental realization of the QAH effect in moir´e superlattices.Furthermore,this review highlights the underlying mechanisms driving these exotic phases in moir´e materials,contributing to a deeper understanding of strongly interacting quantum systems and facilitating the manipulation of new material properties to achieve novel quantum states. 展开更多
关键词 quantum anomalous Hall effect magic-angle twisted bilayer graphene moirésuperlattices
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SHEsis,a powerful software platform for analyses of linkage disequilibrium,haplotype construction,and genetic association at polymorphism loci 被引量:393
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作者 Yong Yong SHI lin he 《Cell Research》 SCIE CAS CSCD 2005年第2期97-98,共2页
In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values w... In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values with a large numberof samples has been sought for long. In order to achieve the goal of obtaining meaningful results directly from raw data,we developed a robust and user-friendly software platform with a series of tools for analysis in association study withhigh efficiency. The platform has been well evaluated by several sets of real data. 展开更多
关键词 SOFTWARE linkage disequilibrium haplotype analysis genetic association study.
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Recent progress in the study of Hedgehog signaling 被引量:9
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作者 Gang Ma Yue Xiao lin he 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第3期129-137,共9页
The Hedgehog (Hh) family of secreted signaling proteins plays a critical role in regulating the development of several tissues and organ systems. The ability of Hh proteins to exert their biological effects is regul... The Hedgehog (Hh) family of secreted signaling proteins plays a critical role in regulating the development of several tissues and organ systems. The ability of Hh proteins to exert their biological effects is regulated by a series of post-translational processes. These processes include an intramolecular cleavage, covalent addition of cholesterol and/or palmitate, and conversion into a multimeric freely diffusible form. The processing of Hh proteins affects their trafficking, potency, and ability to signal over several cell diameters. Here we review the current understanding of the Hh signaling mechanisms that govern the establishment of the Hh gradient and the transduction of the Hh signal in the light of recent data. 展开更多
关键词 HEDGEHOG PROCESSING signal transduction
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Targeted inhibition of Notch1 gene enhances the killing effects of Paclitaxel on triple-negative breast cancer cells 被引量:3
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作者 Yu-Fu Zhou Qian Sun +7 位作者 Ya-Jun Zhang Geng-Ming Wang Bin he Tao Qi Yan Zhou Xing-Wang Li Sheng Li lin he 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第2期172-176,共5页
Objective:To study the influence of targeted inhibition of Notch1 gene on the killing effects of Paclitaxel on triple-negative breast cancer cells.Methods:The triple-negative [estrogen receptor(ER)/progesterone recept... Objective:To study the influence of targeted inhibition of Notch1 gene on the killing effects of Paclitaxel on triple-negative breast cancer cells.Methods:The triple-negative [estrogen receptor(ER)/progesterone receptor(PR)/human epidermal growth factor receptor 2(Her2)] breast cancer cell line MDA-MB-231 and ER/PR/HER-2-positive breast cancer cell line MCF-7 were cultured,transfected with Notch1-si RNA-overexpression plasmid and blank plasmid,and treated with different concentrations of paclitaxel,and then the cell proliferation activity and apoptosis rate as well as the m RNA expression of Caspase-3,Caspase-9 and Bcl-2 were determined.Results:Paclitaxel could decrease the MDA-MB-231 and MCF-7 cell proliferation activity as well as Bcl-2 mRNA expression,and increase MDA-MB-231 and MCF-7 cell apoptosis rate as well as Caspase-3 and Caspase-9 mRNA expression in dosedependent manners;with the same dose of paclitaxel treatment,the inhibitory effects on MDAMB-231 cell proliferation activity and Bcl-2 m RNA expression as well as the promoting effects on MDA-MB-231 cell apoptosis and mR NA expression of Caspase-3 and Caspase-9 were weaker than those on MCF-7 cell;after 0.5 μM paclitaxel combined with Notch1-siRNA treatment,MDA-MB-231 cell proliferation activity and Bcl-2 mRNA expression were significantly lower than those after 0.5 μM paclitaxel combined with control plasmid treatment while cell apoptosis rate and mR NA expression of Caspase-3 and Caspase-9 were higher than those after 0.5 μM paclitaxel combined with control plasmid treatment.Conclusions:Targeted inhibition of Notch1 gene may enhance the killing effects of paclitaxel on triple-negative breast cancer cells by up-regulating the expression of Caspase-3 and Caspase-9 and inhibiting the expression of Bcl-2. 展开更多
关键词 Triple-negative breast cancer PACLITAXEL Notch1 gene Drug resistance Cell apoptosis
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Electronic-property dependent interactions between tetracycline and graphene nanomaterials in aqueous solution 被引量:6
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作者 lin he Fei-fei Liu +7 位作者 Mengyao Zhao Zhen Qi Xuefei Sun Muhammad Zaheer Afzal Xiaomin Sun Yanhui Li Jingcheng Hao Shuguang Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第4期286-294,共9页
Understanding the interactions between graphene nanomaterials(GNMs) and antibiotics in aqueous solution is critical to both the engineering applications of GNMs and the assessment of their potential impact on the fa... Understanding the interactions between graphene nanomaterials(GNMs) and antibiotics in aqueous solution is critical to both the engineering applications of GNMs and the assessment of their potential impact on the fate and transport of antibiotics in the aquatic environment. In this study, adsorption of one common antibiotic, tetracycline, by graphene oxide(GO) and reduced graphene oxide(RGO) was examined with multi-walled carbon nanotubes(MWCNTs) and graphite as comparison. The results showed that the tetracycline adsorption capacity by the four selected carbonaceous materials on the unit mass basis followed an order of GO &gt; RGO &gt; MWCNTs &gt; graphite. Upon normalization by surface area,graphite, RGO and MWCNTs had almost the same high tetracycline adsorption affinity while GO exhibited the lowest. We proposed π-electron-property dependent interaction mechanisms to explain the observed different adsorption behaviors. Density functional theory(DFT) calculations suggested that the oxygen-containing functional groups on GO surface reduced its π-electron-donating ability, and thus decreased the π-based interactions between tetracycline and GO surface. Comparison of adsorption efficiency at different p H indicated that electrostatic interaction also played an important role in tetracycline-GO interactions. Site energy analysis confirmed a highly heterogeneous distribution of the binding sites and strong tetracycline binding affinity of GO surface. 展开更多
关键词 Graphene oxide Reduced graphene oxide Tetracycline Adsorption DFT calculation π-Based interaction
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Effect and mechanism of baicalin and geniposide on excitotoxicity of acute cerebral ischemia
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作者 Huan-huan ZHANG Han LIU +6 位作者 Yuan-xue GAO lin he Jie WU Jing-yun XIANG Min LI Bin WANG Ya-guo KANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期333-334,共2页
OBJECTIVE Based on the methods of microdialysis,HPLC-MS/MS and gene chip tech.nology,the mechanism of Baicalin and Geniposide(BC/GP) against excitatory amino acid toxicity in ce.rebral ischemia was studied.This will p... OBJECTIVE Based on the methods of microdialysis,HPLC-MS/MS and gene chip tech.nology,the mechanism of Baicalin and Geniposide(BC/GP) against excitatory amino acid toxicity in ce.rebral ischemia was studied.This will provide guidance for the clinical application of BC/GP and the study of excitatory amino acid toxicity in cerebral ischemia.METHODS(1) Microdialysis technique and HPLC-MS/MS was performed to study the pharmacodynamics of BC/GP against cerebral ischemia.(1)18 SD rats with body weight of(280±20) g were randomly divided into control group,treatment groups with BC/CP at low dose,medium dose and high dose(equal to the dosage of crude drugs for 30 mg·kg^(-1),45 mg·kg^(-1) and 60 mg·kg^(-1) respectively).Rats in each group were given intragastric administration for seven days to establish cerebral ischemia model.Then,microdialysis probe was applied to collect cerebrospinal fluid from hippocampus before and after cerebral ischemia.(2) First,we established the HPLC-MS/MS method for measuring drugs and excitatory amino acids.Then we detected the microdi.alysis samples and observed their changes in animals.(2) The mechanism of BC/GP against excitatory toxicity of cerebral ischemia were observed at gene level by chip technique.(1) 16 SD rats with body weight of 240±20 g were randomly divided into sham group,model group,treatment group of BC(60 mg·kg^(-1)),treatment group of GP(60 mg·kg^(-1)) and treatment group of BC/GP(7:3)(60 mg·kg^(-1)).Rats in eachgroup were given intragastric administration for seven days to establish cerebral ischemia model.Then the rats were sacrificed,and the hippocampus were rapidly harvested and stored at-80℃ for further detection.(2) After the quality inspection of the hippocampal,the qualified samples were subjected to detect the levels of neurotransmitter receptor gene in the ischemic of rats by gene chip technology.Finally,the results were analyzed by the method of ΔΔCt.RESULTS(1) Only three compounds includ.ed GP,glutamic acid and aspartic acid were detected in microdialysis samples by HPLC-MS/MS.The concentration of GP increased and lasted for 120 min with a significant dose-dependent after cerebral ischemia.Compared with low dose group,the AUC(0-t),MRT(0-∞),Cmax and t1/2 z in high-dose group showed significant difference(P<0.01).Compared with the model group,the levels of glutamic acid and aspartic acid in the treatment groups decreased significantly,especially in the middle and high dose groups.(2)89 genes in the neurotransmitter receptor gene signaling pathway were detected by gene chip technol.ogy.There were 22 genes with |Fold Regulation| >1.5 in the model group,compared with the sham group.Five of the 22 genes showed statistically significant differences,including Grin2 c(2.9026),Chrna7(-1.5877),and Tacr2(-1.7695).Htr3 a(-1.8172) and Grm6(-2.3527).There were 5 genes with |Fold Regulation|>1.5 in the BC group,compared with the model group,Two of them exhibited statistically significant differences,including Brs3(1.797)and Grin2 c(-1.7979).There were 14 genes with |Fold Reg.ulation| >1.5 in the GP group,compared with the model group.Three of them displayed statistically significant differences,including Hcrtr2(-1.6584),Sctr(-3.8524) and Grin2 c(-4.8408).Compared with model group,the genes of |Fold Regulation| >1.5 in BC/GP(7:3) group are 5,and only one of them showed a significant differences.CONCLUSION(1) After administration of BC and GP,GP can cross the blood-brain barrier and reduce the release of excitatory amino acids in the hippocampus.(2) BC/GP can inhibit the interaction between excitatory amino acids and excitatory amino acid receptors and attenuate the toxicity of excitatory amino acids by down-regulating the expression of glutamic acid receptor Grin2 c gene.(3) BC/GP may exert their brain protection effect by reducing the release of excit.atory amino acids and inhibiting the expression of excitatory amino acid receptors. 展开更多
关键词 基因芯片技术 脑缺血 治疗方法 临床分析
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Anti-inflammatory Effect of Heat-sensitive Moxibustion via the NF-κB Signaling Pathway on Cerebral Ischemia/Reperfusion Injury in Rats
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作者 Aijiao Xiaoa Yisheng Xiaoa +2 位作者 Xin OuYang lin he Mingren Chen 《Journal of Advances in Medicine Science》 2018年第3期67-79,共13页
Ischemic stroke is universally acknowledged as a common cause of long-term disability or even death. Suspended moxibustion, an indirect form of moxibustion, is when moxibustion is placed superficially over the skin wi... Ischemic stroke is universally acknowledged as a common cause of long-term disability or even death. Suspended moxibustion, an indirect form of moxibustion, is when moxibustion is placed superficially over the skin without being in contact with it. Some researchers have used this method to treat stroke patients, but strong evidence of its therapeutic effectiveness is lacking. However, the effect of traditional suspended moxibustion has recently been improved with the development of heat-sensitive suspended moxibustion. Our previous studies showed that moxibustion for 35 min provided a more effective treatment strategy than moxibustion for 15 min, and moxibustion by 35 min with tail temperature increase had a better outcome than that without, however, the mechanism underlying the effect is not clear. In this study, we treated the stroke rats with moxibustion by 35min and divided them into non-heat sensitive moxibustion(NHSM) group and heat sensitive moxibustion (HSM) group according to difference in the tail temperature increase, then we compared the effect and investigated the mechanisms between NHSM and HSM. We found that HSM significantly decreased tail-flick latency, increased neurological function score, decreased infarct volume, reduced inflammatory cells, decreased the expression of inflammatory factor ICAM-1 and reduced the expression of NF-κB p65 and p-IKKα/β in rats with focal cerebral ischemia/reperfusion injury. Our experimental findings revealed that HSM exerted its anti-inflammatory and neuroprotective effects from MCAO-induced injury by decreasing the expression of the NF-κB signaling pathway. 展开更多
关键词 Auspended MOXIBUSTION HEAT-SENSITIVE MOXIBUSTION Middle CEREBRAL artery occlusion CEREBRAL ISCHEMIA/REPERFUSION injury Tail temperature TAIL-FLICK latency INFARCT volume Inflammatory cells CD11b ICAM-1 NF-κB p65 p-IKKα/β Traditional Chinese Medicine
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Simulation of the emission lines radiated from cataclysmic variables
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作者 lin he Guo-Liang Lü Yong-heng Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第10期1213-1218,共6页
Cataclysmic variables are special celestial bodies because they have particular light curves and spectra.The mechanisms for generating emission lines radiated from dwarf novae in their quiescent phases are studied.We ... Cataclysmic variables are special celestial bodies because they have particular light curves and spectra.The mechanisms for generating emission lines radiated from dwarf novae in their quiescent phases are studied.We assume that the incident radiation field which is emitted by a hot source(white dwarf and boundary layer)irradiates the gaseous layer evaporated from the accretion disk,and the emission lines are radiated from the gas.We model the fluxes of emission lines by using the photoionization code CLOUDY.Using this method,we input some reasonable parameters and get a series of simulated spectra.In order to find a simulated spectrum which is the best fit to an observed spectrum,we use a cross-correlation method to match them.After the calculation,we use the approximation that the parameters of the simulated spectrum can simulate the observed spectrum.Finally,we learn more about the physical conditions of the system. 展开更多
关键词 stars:cataclysmic variables accretion disk:emission lines emission lines:photoionization
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超声内镜测定门静脉压力梯度的临床意义
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作者 马颖慧 林赫 +2 位作者 王磊 张裕 赵亚莉 《肝脏》 2025年第3期301-304,共4页
目的 探究超声内镜在肝硬化门静脉高压患者门静脉压力梯度(PPG)测定中的应用价值。方法 选取2022年1月至2023年10月在北京佑安医院收治的疑似肝硬化门静脉高压患者122例。通过超声内镜测定PPG,经右颈静脉穿刺测定肝静脉压力梯度(HVPG)... 目的 探究超声内镜在肝硬化门静脉高压患者门静脉压力梯度(PPG)测定中的应用价值。方法 选取2022年1月至2023年10月在北京佑安医院收治的疑似肝硬化门静脉高压患者122例。通过超声内镜测定PPG,经右颈静脉穿刺测定肝静脉压力梯度(HVPG)。对比有无肝硬化门静脉高压、不同程度以及不同肝功能等级的肝硬化门静脉高压患者的PPG以及HVPG。通过受试者工作曲线下面积(AUC)分析PPG值对肝硬化门静脉高压及其严重程度的诊断价值。结果 超声内镜引导测定PPG值的手术成功率为98.4%(120/122)。采用超声内镜测得PPG值(18.74±10.1)mmHg,经颈静脉穿刺测得HVPG值(19.06±8.2)mmHg,差异无统计学意义(t=0.269,P=0.788)。无门静脉高压组患者的PPG为(10.7±3.3)mmHg,有门静脉高压组为(20.7±10.5)mmHg;轻度门静脉高压组的PPG为(16.2±4.1)mmHg,重度门静脉高压组为(25.2±7.6)mmHg,差异均有统计学意义(t=5.646、7.230,P<0.001)。Child肝功能A级、B级以及C级患者PPG值分别为(16.2±8.3)mmHg、(18.9±7.3)mmHg、(17.3±8.8)mmHg,差异无统计学意义(F=1.657,P=0.195)。PPG诊断门静脉高压的AUC为0.981,诊断门静脉高压严重程度的AUC为0.947,均有较好的诊断价值。结论 对于肝硬化门静脉高压患者的诊断采用超声内镜引导下PPG的测定可以替代HVPG的测定。 展开更多
关键词 超声内镜 肝硬化 门静脉压力梯度 门静脉高压 应用
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玉米须总黄酮对大鼠尿酸性肾病的改善作用及其机制
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作者 路静 刘萌萌 +6 位作者 韩跃威 黄晓巍 王雨辰 林贺 张天柱 林喆 律广富 《吉林大学学报(医学版)》 北大核心 2025年第4期929-938,共10页
目的:探讨玉米须总黄酮(TFCS)对尿酸性肾病模型大鼠肾脏损伤的改善作用,并阐明其可能的机制。方法:60只Wistar雄性大鼠随机分为对照组、模型组、阳性对照组[苯溴马隆(BZM)组,5 mg·kg^(-1)·d^(-1)]、低剂量TFCS组(20 mg·k... 目的:探讨玉米须总黄酮(TFCS)对尿酸性肾病模型大鼠肾脏损伤的改善作用,并阐明其可能的机制。方法:60只Wistar雄性大鼠随机分为对照组、模型组、阳性对照组[苯溴马隆(BZM)组,5 mg·kg^(-1)·d^(-1)]、低剂量TFCS组(20 mg·kg^(-1)·d^(-1))、中剂量TFCS组(40 mg·kg^(-1)·d^(-1))和高剂量TFCS组(80 mg·kg^(-1)·d^(-1)),每组10只。除对照组外,其余各组大鼠灌服350 mg·kg^(-1)氧嗪酸钾+70 mg·kg^(-1)腺嘌呤4周,建立尿酸性肾病大鼠模型,不同剂量TFCS组大鼠连续灌服TFCS 2周。散斑血流成像仪检测各组大鼠肾脏血液灌注情况并计算各组大鼠肾脏系数,HE染色法和Masson染色法检测各组大鼠肾组织病理形态表现及纤维化程度,酶联免疫吸附试验(ELISA)法检测各组大鼠血清中尿酸(UA)、肌酐(Cr)、血尿素氮(BUN)、白细胞介素6(IL-6)和肿瘤坏死因子α(TNF-α)水平以及尿液中β2-微球蛋白(β2-MG)和微量白蛋白(ALB)水平,Western blotting法检测各组大鼠肾组织中尿酸盐转运蛋白1(URAT1)、葡萄糖转运蛋白9(GLUT9)和ATP结合转运蛋白G2(ABCG2)蛋白表达水平。结果:与对照组比较,模型组大鼠肾脏血流灌注量明显降低(P<0.01);与模型组比较,BZM组和低、中及高剂量TFCS组大鼠肾脏血流灌注量均升高(P<0.05或P<0.01)。与对照组比较,模型组大鼠肾脏质量增加,肉眼可观察到肾脏表面有白色颗粒状斑点,无血色,体积增加;与模型组比较,BZM组和中及高剂量TFCS组大鼠肾脏体积减小,颜色趋于对照组,表面白色颗粒状斑点明显减少。与模型组比较,BZM组和中及高剂量TFCS组大鼠肾脏系数降低(P<0.01)。HE染色法,对照组大鼠肾组织结构无异常;模型组大鼠肾组织可见少量棕黄色尿酸结晶沉积,间质结缔组织增生;与模型组比较,BZM组和不同剂量TFCS组大鼠肾组织损伤均有不同程度减轻,炎症浸润减轻。Masson染色法,对照组大鼠肾组织未见明显胶原纤维沉积;模型组大鼠肾组织可见大量蓝色胶原纤维沉积,胶原容积分数(CVF)较对照组升高(P<0.01);与模型组比较,BZM组和不同剂量TFCS组大鼠CVF降低(P<0.01)。ELISA法,与对照组比较,模型组大鼠血清中UA、Cr、BUN、IL-6和TNF-α水平升高(P<0.01);与模型组比较,BZM组和中及高剂量TFCS组大鼠血清中UA、Cr、BUN、IL-6和TNF-α水平降低(P<0.01)。与对照组比较,模型组大鼠尿液中β2-MG和ALB水平升高(P<0.01);与模型组比较,BZM组和不同剂量TFCS组大鼠尿液中β2-MG和ALB水平降低(P<0.05或P<0.01)。Western blotting法,与对照组比较,模型组大鼠肾组织中URAT1和GLUT9蛋白表达水平升高(P<0.01),ABCG2蛋白表达水平降低(P<0.01);与模型组比较,BZM组和不同剂量TFCS组大鼠肾组织中URAT1和GLUT9蛋白表达水平均降低(P<0.05或P<0.01),ABCG2蛋白表达水平均升高(P<0.01)。结论:TFCS能明显减轻尿酸性肾病模型大鼠的肾脏损伤,其机制可能与TFCS降低肾组织中URAT1和GLUT9蛋白表达水平及升高ABCG2蛋白表达水平有关联。 展开更多
关键词 玉米须黄酮提取物 尿酸性肾病 血液灌注 尿酸转运体 肾脏损伤
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苍术野生品与栽培品的药效学比较
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作者 林智 王心荷 +5 位作者 张文静 王雨辰 律广富 孙铭阳 林贺 林喆 《中药新药与临床药理》 北大核心 2025年第2期214-218,共5页
目的基于燥湿健脾、祛风散寒的传统功效,比较吉林产区的苍术野生品与栽培品的药效学差异。方法采用醋酸致小鼠扭体实验、二甲苯致小鼠耳肿胀实验、小鼠肉芽肿实验、小鼠小肠推进实验及HCl(0.6 mol·L^(-1))致大鼠胃溃疡实验,分别比... 目的基于燥湿健脾、祛风散寒的传统功效,比较吉林产区的苍术野生品与栽培品的药效学差异。方法采用醋酸致小鼠扭体实验、二甲苯致小鼠耳肿胀实验、小鼠肉芽肿实验、小鼠小肠推进实验及HCl(0.6 mol·L^(-1))致大鼠胃溃疡实验,分别比较苍术野生品与栽培品在镇痛、抗炎、肠推进和抗胃溃疡等方面的作用。苍术水煎液灌胃的小鼠低、中、高剂量为1.5、3、6 g·kg^(-1),大鼠低、中、高剂量为1、2、4 g·kg^(-1)。结果与模型组比较,野生苍术高剂量组及栽培苍术中、高剂量组小鼠的扭体次数均明显减少,镇痛率显著提高(P<0.05,P<0.01),耳肿胀质量明显降低,抑制率显著升高(P<0.05,P<0.01);野生、栽培苍术中、高剂量组小鼠的肉芽肿质量均明显降低,抑制率显著升高(P<0.05,P<0.01),墨水推进率、促进率均显著提高(P<0.05,P<0.01);野生、栽培苍术中、高剂量组大鼠的溃疡面积均显著缩小,抑制率显著升高(P<0.01)。相同剂量的野生、栽培苍术的镇痛、抗炎效果及小肠推进功能、抗胃溃疡作用均无明显差异(P>0.05)。结论吉林产区的野生和栽培苍术在镇痛、抗炎、肠推进及抗胃溃疡等方面均有明显作用,且相同剂量的野生、栽培苍术的药效无明显差异。 展开更多
关键词 野生苍术 栽培苍术 药效差异 镇痛 抗炎 肠推进 抗胃溃疡 小鼠 大鼠
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超超临界机组主蒸汽管道焊接接头失效与评估研究综述
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作者 孙戬 潘晨阳 +4 位作者 刘福广 赵小惠 林何 刘晖 成小乐 《热加工工艺》 北大核心 2025年第18期9-20,共12页
超超临界高温高压工况易导致火电厂机组主蒸汽管道上的焊接接头在服役中萌生裂纹,造成早期失效,严重影响机组建设及运行的安全稳定。综述了超超临界火电机组管道焊接接头早期失效的影响因素、蠕变行为特性以及接头裂纹失效评定法则的发... 超超临界高温高压工况易导致火电厂机组主蒸汽管道上的焊接接头在服役中萌生裂纹,造成早期失效,严重影响机组建设及运行的安全稳定。综述了超超临界火电机组管道焊接接头早期失效的影响因素、蠕变行为特性以及接头裂纹失效评定法则的发展与应用,并展望了此领域未来研究的重点与方向,为电厂预防高温热力管道焊接接头早期失效及结构完整性评估提供理论参考与研究基础。 展开更多
关键词 焊接接头 蠕变失效 超超临界机组 失效评估 主蒸汽管道
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2-脱氧葡萄糖联合二甲双胍抗人肝癌HepG2细胞作用及与AMPK、mTOR相关性研究
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作者 林鹤 于娜 +4 位作者 常宁 杨冬华 杨金玲 任利翔 邢立国 《药物评价研究》 CAS 2018年第12期2195-2200,共6页
目的考察2-脱氧葡萄糖(2-DG)联合二甲双胍(Met)协同抗人肝癌HepG2细胞作用并探索其机制。方法刃天青法测定2-DG及Met单独及联合应用对HepG2细胞的生长抑制作用,利用金氏公式计算联合用药Q值;利用高内涵细胞成像系统考察单独及联合用药... 目的考察2-脱氧葡萄糖(2-DG)联合二甲双胍(Met)协同抗人肝癌HepG2细胞作用并探索其机制。方法刃天青法测定2-DG及Met单独及联合应用对HepG2细胞的生长抑制作用,利用金氏公式计算联合用药Q值;利用高内涵细胞成像系统考察单独及联合用药对细胞线粒体膜电位及活性氧产生的影响;Western blotting检测Cleave-Caspase 3、p-AMPK及p-mTOR的蛋白变化;考察AMPK及mTOR抑制剂对联合用药后细胞生长抑制作用的影响。结果 2-DG、Met单独应用的IC50值分别为2.45及16.35 mmol/L,联合用药对细胞生长抑制具有协同作用,Q值均大于1.15;联合用药能显著降低细胞内线粒体膜电位及p-mTOR蛋白表达,显著增加细胞内活性氧产生及Cleave-Caspase3、p-AMPK蛋白表达;抑制AMPK或mTOR能显著增加联合用药对细胞的生长抑制作用(P<0.05、0.01)。结论 2-DG联合Met具有协同抑制HepG2细胞增殖作用,其机制与降低细胞线粒体膜电位,促进活性氧产生、细胞凋亡,以及非AMPK依赖性的抑制mTOR活化有关。 展开更多
关键词 2-脱氧葡萄糖 二甲双胍 HepG2细胞 AMPK MTOR
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碳酸二烷酯燃料与发动机非金属材料的相容性
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作者 杨国峰 张聪 +2 位作者 王箐旋 林赫 韩东 《哈尔滨工程大学学报》 北大核心 2025年第5期908-919,共12页
针对碳酸二烷酯燃料与发动机材料相容性问题,本文通过相容性模拟计算与实验分析了橡胶和塑料材料在碳酸二烷酯燃料中的性质和机械性能变化。在碳酸二烷酯的加入下,柴油混合物溶解度参数提升,橡胶质量体积和机械性能显著变化,氟橡胶在掺... 针对碳酸二烷酯燃料与发动机材料相容性问题,本文通过相容性模拟计算与实验分析了橡胶和塑料材料在碳酸二烷酯燃料中的性质和机械性能变化。在碳酸二烷酯的加入下,柴油混合物溶解度参数提升,橡胶质量体积和机械性能显著变化,氟橡胶在掺有50%碳酸二烷酯的柴油混合物中相容性较好。对于塑料,聚丙烯和聚四氟乙烯表现出良好的相容性。 展开更多
关键词 碳酸二烷酯燃料 材料相容性 相容性模拟计算 相容性综合指数 溶解度参数 扩散系数 机械性能 质量体积变化
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RC、RL和RLC串联电路幅频及相频特性实验优化研究
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作者 陈悦华 冯卓宏 +5 位作者 庄滟彤 王哲哲 林鹤 郑卫峰 姚胡蓉 王丽丽 《实验室科学》 2025年第4期188-192,共5页
通过对比数字万用表和示波器在RC、RL及RLC串联电路中的幅频与相频特性测量表现,探讨了阻抗匹配和信号频率对测量精度的影响。实验结果表明,万用表适用于频率低于1500Hz的幅频测量,在高频或低阻抗电路中误差可能超过5%;示波器在3kHz范... 通过对比数字万用表和示波器在RC、RL及RLC串联电路中的幅频与相频特性测量表现,探讨了阻抗匹配和信号频率对测量精度的影响。实验结果表明,万用表适用于频率低于1500Hz的幅频测量,在高频或低阻抗电路中误差可能超过5%;示波器在3kHz范围内表现出更高的稳定性,误差可控制在5%以内。相频测量中,两种仪器均能提供准确结果,仅当相位角极小时相对误差较明显。此外,RLC电路的谐振频率测量值与理论值高度吻合。研究为优化电路参数和测量工具选择提供了实践依据,对高校物理实验教学具有参考价值。 展开更多
关键词 RC/RL/RLC串联电路 幅频特性 相频特性 万用表 示波器
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织物增强橡胶基复合材料本构模型及其应用
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作者 孙戬 王彤 +3 位作者 陈云辉 林何 刘晖 成小乐 《纺织学报》 北大核心 2025年第1期95-102,共8页
为更准确地表征织物增强橡胶基复合材料在受力变形过程中的力学性能,针对二维编织物结构,基于连续介质力学将织物增强橡胶基复合材料应变能解耦为橡胶基体应变能、纤维拉伸应变能以及纤维之间相互作用引起的剪切应变能,结合橡胶、织物... 为更准确地表征织物增强橡胶基复合材料在受力变形过程中的力学性能,针对二维编织物结构,基于连续介质力学将织物增强橡胶基复合材料应变能解耦为橡胶基体应变能、纤维拉伸应变能以及纤维之间相互作用引起的剪切应变能,结合橡胶、织物增强复合材料的单轴拉伸及镜框剪切实验数据拟合得到本构模型参数。通过对织物增强密封带压缩仿真结果与实验数据进行比较,验证了所建立的舱门密封有限元模型的有效性,随后将织物增强橡胶基复合材料超弹性本构模型应用于飞机舱门压缩过程的模拟分析。结果表明:超弹性本构模型能够用于表征织物增强复合材料的各向异性非线性材料行为;经向/纬向纤维与密封带轴向呈0°角铺设方式的密封性能优于45°角铺设,舱门的密封性能与门框的加载量成正比关系。 展开更多
关键词 机织物 橡胶 织物增强复合材料 橡胶密封件 本构模型 舱门密封带 密封性 有限元法
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