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Profiles and Source Apportionment of Nonmethane Volatile Organic Compounds in Winter and Summer in Xi’an, China, based on the Hybrid Environmental Receptor Model 被引量:4
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作者 Jian SUN Zhenxing SHEN +8 位作者 Yue ZHANG Wenting DAI Kun HE Hongmei XU Zhou ZHANG Long CUI Xuxiang LI Yu HUANG Junji CAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第1期116-131,共16页
Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment mon... Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols). 展开更多
关键词 NMHCS OVOCs source apportionment Hybrid Environmental receptor model
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PM_(2.5) source apportionment in a French urban coastal site under steelworks emission influences using constrained non-negative matrix factorization receptor model 被引量:3
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作者 Adib Kfoury Frederic Ledoux +3 位作者 Cloe Roche Gilles Delmaire Gilles Roussel Dominique Courcot 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第2期114-128,共15页
The constrained weighted-non-negative matrix factorization(CW-NMF)hybrid receptor model was applied to study the influence of steelmaking activities on PM_(2.5)(particulate matter with equivalent aerodynamic diameter ... The constrained weighted-non-negative matrix factorization(CW-NMF)hybrid receptor model was applied to study the influence of steelmaking activities on PM_(2.5)(particulate matter with equivalent aerodynamic diameter less than 2.5μm)composition in Dunkerque,Northern France.Semi-diurnal PM_(2.5)samples were collected using a high volume sampler in winter 2010 and spring 2011 and were analyzed for trace metals,water-soluble ions,and total carbon using inductively coupled plasma–atomic emission spectrometry(ICP-AES),ICP-mass spectrometry(ICP-MS),ionic chromatography and micro elemental carbon analyzer.The elemental composition shows that NO_(3)^(-),SO_(4)^(2-),NH_4~+and total carbon are the main PM_(2.5)constituents.Trace metals data were interpreted using concentration roses and both influences of integrated steelworks and electric steel plant were evidenced.The distinction between the two sources is made possible by the use Zn/Fe and Zn/Mn diagnostic ratios.Moreover Rb/Cr,Pb/Cr and Cu/Cd combination ratio are proposed to distinguish the ISW-sintering stack from the ISW-fugitive emissions.The a priori knowledge on the influencing source was introduced in the CW-NMF to guide the calculation.Eleven source profiles with various contributions were identified:8 are characteristics of coastal urban background site profiles and 3 are related to the steelmaking activities.Between them,secondary nitrates,secondary sulfates and combustion profiles give the highest contributions and account for 93%of the PM_(2.5)concentration.The steelwork facilities contribute in about 2%of the total PM_(2.5)concentration and appear to be the main source of Cr,Cu,Fe,Mn,Zn. 展开更多
关键词 PM_(2.5) receptor modeling Non-negative matrix factorization Source apportionment Steelworks
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Source Apportionment of PM2.5 in the Metropolitan Area of Costa Rica Using Receptor Models
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作者 Jorge Herrera Murillo Susana Rodríguez Roman +1 位作者 José Félix Rojas Marín Beatriz Cardenas 《Atmospheric and Climate Sciences》 2013年第4期562-575,共14页
In this work, receptor models were used to identify the PM2.5 sources and its contribution to the air quality in residential, comercial and industrial sampling sites in the Metropolitan Area of Costa Rica. Principal c... In this work, receptor models were used to identify the PM2.5 sources and its contribution to the air quality in residential, comercial and industrial sampling sites in the Metropolitan Area of Costa Rica. Principal component analysis with absolute principal component scores (PCA-APCS), UNIMX and positive matrix factorization (PMF) was applied to analyze the data collected during 1 year of sampling campaign (2010-2011). The PM2.5 samples were characterized through its composition looking for trace elements, inorganic ions and organic and elemental carbon. These three models identified some common sources of PM2.5: marine aerosol, crustal material, traffic, secondary aerosols (secondary sulfate and secondary nitrate resolved by PMF), a mixed source of heavy fuels combustion and biomass burning, and industrial emissions. The three models predicted that the major sources of PM2.5 in the Metropolitan Area of Costa Rica were related to anthropogenic sources (73%, 65% and 69%, respectively, for PCA-APCS, Unmix and PMF) although natural sources also contributed to PM2.5 (21%, 24% and 26%). On average, PCA and PMF methods resolved 94% and 95% of the PM2.5 mass concentrations, respectively. The results were comparable to the estimate using UNMIX. 展开更多
关键词 PM2.5 Chemical COMPOSITION Costa Rica SOURCE APPORTIONMENT receptor models
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Source apportionment of polycyclic aromatic hydrocarbons(PAHs)in a sediment core from Lake Dagze Co,Tibetan Plateau,China:Comparison of three receptor models
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作者 Yixin Bai Kunlin Shi +6 位作者 Heyu Yu Nana Shang Weiyue Hao Chuan Wang Tao Huang Hao Yang Changchun Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第11期224-233,共10页
Receptor models are a useful tool for identifying sources of polycyclic aromatic hydrocarbons(PAHs)in multiple environmental media.In this study,three different receptor models(including the principal component analys... Receptor models are a useful tool for identifying sources of polycyclic aromatic hydrocarbons(PAHs)in multiple environmental media.In this study,three different receptor models(including the principal component analysis-multiple linear regression(PCA-MLR),positive matrix factorization(PMF),and Unmix models)were used to apportion the sources of 16 priority PAHs in a sediment core of Lake Dagze Co.TheΣPAHs(sum of all 16 measured PAHs)concentrations ranged from 51.89 to 132.82 ng/g with an average of 80.39 ng/g.TheΣPAHs were dominated by 2-3 ring PAHs,accounting for 80.12%on average,thereby indicating that they mainly originated from biomass and coal combustion and/or from long-range atmospheric transportation.The three models produced consistent source apportionment results.The greatest contributor toΣPAHs was biomass combustion,followed by coal combustion,vehicle emissions,and petrogenic sources.Moreover,the temporal variation of the common sources was well-correlated among models.The multi-method comparison and evaluation results showed that all three models were useful tools for source apportionment of PAHs,with the PMF model providing better results than the PCA-MLR and Unmix models.The temporal trends of factor contributions were verified by PAHs with different ring numbers.Significant correlations were found between the simulated concentrations of each source factor and the PAHs with different ring numbers(P<0.01),except for the petrogenic source identified by the Unmix model(P>0.05).This study can provide useful information for further investigation of source apportionment of PAHs in the sediment cores. 展开更多
关键词 Polycyclic aromatic hydrocarbons(PAHs) Source apportionment receptor models Sediment core Tibetan Plateau
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Human androgen deficiency: insights gained from androgen receptor knockout mouse models 被引量:13
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作者 Kesha Rana Rachel A Davey Jeffrey D Zajac 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第2期169-177,I0006,共10页
The mechanism of androgen action is complex. Recently, significant advances have been made into our understanding of how androgens act via the androgen receptor (AR) through the use of genetically modified mouse mod... The mechanism of androgen action is complex. Recently, significant advances have been made into our understanding of how androgens act via the androgen receptor (AR) through the use of genetically modified mouse models. A number of global and tissue-specific AR knockout (ARKO) models have been generated using the Cre-loxP system which allows tissue- and/or cell-specific deletion. These ARKO models have examined a number of sites of androgen action including the cardiovascular system, the immune and hemopoetic system, bone, muscle, adipose tissue, the prostate and the brain. This review focuses on the insights that have been gained into human androgen deficiency through the use of ARKO mouse models at each of these sites of action, and highlights the strengths and limitations of these Cre-loxP mouse models that should be considered to ensure accurate interpretation of the phenotype. 展开更多
关键词 androgen receptor androgen receptor knockout mouse model androgen deficiency
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Impact of Probiotics on Toll-like Receptor 4 Expression in an Experimental Model of Ulcerative Colitis 被引量:6
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作者 杨霞 付妤 +1 位作者 刘俊 任宏宇 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第5期661-665,共5页
Toll-like receptors (TLRs) are key components of the innate immune system which trigger antimicrobial host defense responses. This study aimed to investigate the impact of probiotics (Lactoba- cillus, Bifiidobacter... Toll-like receptors (TLRs) are key components of the innate immune system which trigger antimicrobial host defense responses. This study aimed to investigate the impact of probiotics (Lactoba- cillus, Bifiidobacterium) on the expression of TLR4 and tumor necrosis factor-alpha (TNF-α in the co- lon mucosa of rat experimental ulcerative colitis model induced by trinitrobenzene sulfonic acid (TNBS)/ethanol and immune complexes. The gross and histological changes of the colonic mucosa were observed and assessed by the means-standard deviation and independent samples t-test. The pro- tein expression levels of TLR4 and TNF-α were detected by using immunohistochemistry and Westem blotting, respectively. It was revealed that there was visible infiltration of inflammatory cells, formation of crypt abscess, and the reduction of goblet cells in the colon tissue of experimental models. As com- pared with the control group, the levels of TLR4 and TNF-α protein were significantly increased in the model group (P〈0.01 for both). No significant difference was found in the expression of TLR4 and TNF-α between the two-week probiotics treatment group and the model group (P〉0.05), whereas sig- nificant reductions were shown in rats which were treated with probiotics for four weeks as compared with the model group (P〈0.01). There was no significant difference between two probiotics-treated groups. Our results implied that probiotics were likely to play a key role in protecting ulcerative colitis by reducing the inflammatory factor TNF-α expression through inhibiting the TLR4 expression in the colon tissue of experimental models. 展开更多
关键词 ulcerative colitis animal model Toll-like receptor 4 tumor necrosis factor-a trinitroben-zene sulfonic acid
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Homology Model and Ligand Binding Interactions of the Extracellular Domain of the Human α4β2 Nicotinic Acetylcholine Receptor
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作者 Shu Mao Hui Wen Ng +5 位作者 Michael Orr Heng Luo Hao Ye Weigong Ge Weida Tong Huixiao Hong 《Journal of Biomedical Science and Engineering》 2016年第1期41-100,共60页
Addiction to nicotine, and possibly other tobacco constituents, is a major factor that contributes to the difficulties smokers face when attempting to quit smoking. Amongst the various subtypes of nicotinic acetylchol... Addiction to nicotine, and possibly other tobacco constituents, is a major factor that contributes to the difficulties smokers face when attempting to quit smoking. Amongst the various subtypes of nicotinic acetylcholine receptors (nAChRs), the α4β2 subtype plays an important role in mediating the addiction process. The characterization of human α4β2-ligand binding interactions provides a molecular framework for understanding ligand-receptor interactions, rendering insights into mechanisms of nicotine addiction and may furnish a tool for efficiently identifying ligands that can bind the nicotine receptor. Therefore, we constructed a homology model of human α4β2 nAChR and performed molecular docking and molecular dynamics (MD) simulations to elucidate the potential human α4β2-ligand binding modes for eleven compounds known to bind to this receptor. Residues V96, L97 and F151 of the α4 subunit and L111, F119 and F121 of the β2 subunit were found to be involved in hydrophobic interactions while residues S153 and W154 of the α4 subunit were involved in the formation of hydrogen bonds between the receptor and respective ligands. The homology model and its eleven ligand-bound structures will be used to develop a virtual screening program for identifying tobacco constituents that are potentially addictive. 展开更多
关键词 Nicotinic Acetylcholine receptors Homology model Ligand-receptor Interactions
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The remedial effect of soluble interleukin-1 receptor type Ⅱ on endometriosis in the nude mouse model 被引量:1
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作者 Liying Gao Liang Sun +6 位作者 Yugui Cui Zhen Hou Li Gao Jing Zhou Yundong Mao Suping Han Jiayin Liu 《The Journal of Biomedical Research》 CAS 2010年第1期43-50,共8页
Objective: Recent studies have shown that the local expression of soluble interleukin (IL) -1 receptor type Ⅱ (slL-1 R Ⅱ ) in endometrial tissue of women with endometriosis is decreased, and the depression of I... Objective: Recent studies have shown that the local expression of soluble interleukin (IL) -1 receptor type Ⅱ (slL-1 R Ⅱ ) in endometrial tissue of women with endometriosis is decreased, and the depression of IL-1 R Ⅱ was more significant in infertile women than that in fertile women with endometriosis. In this research, we investigated the remedial effect of slL-1-R Ⅱ administration on endometriosis in the nude mouse model. Methods: Nineteen nude model mice with endometriosis were randomly divided into three groups: group A was treated by intraperitoneal administration with only slL-1 R Ⅱ for two weeks, group B was similarly treated with only IL- 1, and group C (control) was administered saline. After 2 weeks, the size of the ectopic endometrial lesions was calculated, and the expression of vascular endothelial growth factor (VEGF) and B-cell lymphoma leukemia-2 (Bcl- 2) were detected by immunohistochemistry. The IL-8 and VEGF levels in the peritoneal fluid (PF) and serum were also measured by enzyme-linked immunosorbent assay (ELISA). Results: The mean size of ectopic endometrial lesion did not differ between the three groups (P 〉 0.05). Compared with the control, the expression of VEGF and Bcl-2 was significantly lower in group A, and higher in group B. In the three groups, the levels of IL-8 in the PF and serum were highest in group A, and lowest in group B. Conclusion: slL-1 R Ⅱ may suppresse hyperplasia of ectopic endometriosis, perhaps by reducing the expression of certain cytokines, such as VEGF, IL-8, and Bcl-2, which could provide a new clinical strategy for the treatment of endometriosis. 展开更多
关键词 INTERLEUKIN-1 solubleinterleukin-1 receptor type ENDOMETRIOSIS nude mouse model
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Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta 被引量:1
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作者 Douglas J DiGirolamo Vandana Singhal +2 位作者 Xiaoli Chang Se-Jin Lee Emily L Germain-Lee 《Bone Research》 SCIE CAS CSCD 2015年第1期40-45,共6页
Osteogenesis imperfecta(OI) comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications... Osteogenesis imperfecta(OI) comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B(ACVR2B) in a mouse model of type Ⅲ OI(oim). Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system. 展开更多
关键词 BONE Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta
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Molecular Characterization, 3D Modeling of Grass Carp Interleukin-10 Receptor 1 (IL10R1)
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作者 He Wei Shangnian Wang +2 位作者 Lei Qin Xinyan Wang Hong Zhou 《Engineering(科研)》 2013年第10期214-219,共6页
Interleukin-10 (IL-10) is an important cytokine that plays a pivotal role in natural and adaptive immune systems. However, in lower vertebrates, especially in teleost the receptor of this cytokine is still largely unk... Interleukin-10 (IL-10) is an important cytokine that plays a pivotal role in natural and adaptive immune systems. However, in lower vertebrates, especially in teleost the receptor of this cytokine is still largely unknown. This paper described the cloning and characterization of grass carp interleukin-10 receptor 1 (gcIL10R1) and the 3D structure of its extracellular domain was predicted. The gcIL10R1 cDNA included 180 bp5’ untranslated region (UTR), 870 bp3’ UTR and an open reading frame (ORF) of 1632 bp. The ORF was found to encode a 543 amino acid protein with a putative JAK1 binding site, one STAT3 binding site. The phylogenetic analysis clusters gcIL10R1 with other teleost IL10R1s but independently of the amphibian, avian and mammalian IL10R1s. The 3D structure of its extracellular domain was the first homology model of a fish IL10R1 that revealed a high similarity with its mammalian and avian counterparts. 展开更多
关键词 GRASS CARP INTERLEUKIN-10 receptor 1 Structure Characterization 3D modeling
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Neuroactive alkaloids that modulate the neuronal nicotinic receptor and provide neuroprotection in an Alzheimer's disease model:the case of Teline monspessulana
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作者 Jorge Fuentealba Francisco Saez-Orellana 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第21期1880-1881,共2页
Despite the advances in combinatorial or synthetic chemis- try and bioinformatics, recent literature has demonstrated the relevance of nature and biomass as a source of new molecules to treat different pathologies, i.... Despite the advances in combinatorial or synthetic chemis- try and bioinformatics, recent literature has demonstrated the relevance of nature and biomass as a source of new molecules to treat different pathologies, i.e., bioactive com- pounds obtained from Ecteinascidia turbinate to treat some types of cancer or rapamycin from Streptomyces hygroscop- icus to prevent organ rejection after transplant. This trend will continue simply due to the fact that Mother Nature has been synthesizing molecules for millions of years. In our lab- oratory, we have characterized several compounds obtained from natural sources and that possess important neuronal effects, 展开更多
关键词 Neuroactive alkaloids that modulate the neuronal nicotinic receptor and provide neuroprotection in an Alzheimer’s disease model CASE
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Design of N-11-Azaartemisinins Potentially Active against Plasmodium falciparum by Combined Molecular Electrostatic Potential, Ligand-Receptor Interaction and Models Built with Supervised Machine Learning Methods
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作者 Jeferson Stiver Oliveira de Castro José Ciríaco Pinheiro +5 位作者 Sílvia Simone dos Santos de Morais Heriberto Rodrigues Bitencourt Antonio Florêncio de Figueiredo Marcos Antonio Barros dos Santos Fábio dos Santos Gil Ana Cecília Barbosa Pinheiro 《Journal of Biophysical Chemistry》 CAS 2023年第1期1-29,共29页
N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning m... N-11-azaartemisinins potentially active against Plasmodium falciparum are designed by combining molecular electrostatic potential (MEP), ligand-receptor interaction, and models built with supervised machine learning methods (PCA, HCA, KNN, SIMCA, and SDA). The optimization of molecular structures was performed using the B3LYP/6-31G* approach. MEP maps and ligand-receptor interactions were used to investigate key structural features required for biological activities and likely interactions between N-11-azaartemisinins and heme, respectively. The supervised machine learning methods allowed the separation of the investigated compounds into two classes: cha and cla, with the properties ε<sub>LUMO+1</sub> (one level above lowest unoccupied molecular orbital energy), d(C<sub>6</sub>-C<sub>5</sub>) (distance between C<sub>6</sub> and C<sub>5</sub> atoms in ligands), and TSA (total surface area) responsible for the classification. The insights extracted from the investigation developed and the chemical intuition enabled the design of sixteen new N-11-azaartemisinins (prediction set), moreover, models built with supervised machine learning methods were applied to this prediction set. The result of this application showed twelve new promising N-11-azaartemisinins for synthesis and biological evaluation. 展开更多
关键词 Antimalarial Design MEP Ligand-receptor Interaction Supervised Machine Learning Methods models Built with Supervised Machine Learning Methods
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基于APCS-MLR受体模型的江西省宜丰县土壤重金属来源解析及生态风险评价 被引量:1
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作者 唐志敏 周墨 +6 位作者 张明 张晓东 田福金 刘冰权 周强强 文帮勇 姜宏裕 《环境科学》 北大核心 2025年第7期4674-4683,共10页
土壤中重金属的富集是自然过程和人为活动共同作用的结果,开展土壤重金属来源解析及生态风险评价是服务土壤重金属污染防治的必要手段.为查明江西省宜丰县土壤中重金属来源及其生态风险特征,采集分析了宜丰县表层土壤中重金属含量以及p... 土壤中重金属的富集是自然过程和人为活动共同作用的结果,开展土壤重金属来源解析及生态风险评价是服务土壤重金属污染防治的必要手段.为查明江西省宜丰县土壤中重金属来源及其生态风险特征,采集分析了宜丰县表层土壤中重金属含量以及pH值等指标,采用绝对主成分得分-多元线性回归(APCS-MLR)受体模型解析了土壤中重金属来源并定量计算了各来源贡献率,基于地累积指数法和潜在生态风险指数法对土壤重金属生态风险进行了评价,同时采用GIS技术对土壤重金属的空间分布规律进行了探讨.结果显示,宜丰县土壤中ω(As)、ω(Cd)、ω(Cr)、ω(Cu)、ω(Hg)、ω(Ni)、ω(Pb)和ω(Zn)的平均值分别为9.7、0.211、68、25、0.113、24、37和87 mg·kg^(−1),均高于江西省土壤背景值.受地质背景控制,土壤As、Cr、Cu和Ni的高含量区与区内青白口系变质岩建造的分布相吻合,受人为活动干扰,Cd、Hg、Pb和Zn的空间分布与岩石建造类型分布呈现显著差异.生态风险评价发现宜丰县土壤重金属污染风险总体较低,但局部存在以As、Cd和Hg为主的轻微污染和中等风险.APCS-MLR受体模型解析出了3个重金属来源:As、Cr、Cu和Ni主要为自然来源,贡献率分别为80.06%、69.92%、80.49%和94.27%,Pb和Zn主要为交通来源,贡献率分别为74.73%和66.99%,Cd和Hg主要受工农业来源的控制,贡献率分别为43.62%和58.09%.研究结果可为宜丰县土壤污染防治提供数据理论支撑. 展开更多
关键词 土壤 重金属 来源 APCS-MLR受体模型 生态风险
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基于正定矩阵因子分解模型的污染源解析研究进展及应用前景 被引量:1
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作者 黎海涛 朱心宇 施加春 《环境污染与防治》 北大核心 2025年第1期121-129,共9页
通过对最近10年间(2012—2022年)国内外文献资料检索分析,对正定矩阵因子分解(PMF)模型在环境污染源解析中的研究进行了全面梳理归纳,通过对PMF模型在不同受体和研究对象的污染源解析中应用结果的比较分析,提出了该模型应用存在的缺陷... 通过对最近10年间(2012—2022年)国内外文献资料检索分析,对正定矩阵因子分解(PMF)模型在环境污染源解析中的研究进行了全面梳理归纳,通过对PMF模型在不同受体和研究对象的污染源解析中应用结果的比较分析,提出了该模型应用存在的缺陷及其未来应用前景展望,可为将来更精准的环境污染源解析研究提供科学依据。当前,PMF模型在国内主要应用于大气和土壤等介质中的颗粒物、重金属和有机物等污染源解析,而国外则相对更多集中应用于大气颗粒物源解析。分析发现PMF模型获得的源分析结果与主成分分析法(PCA)、化学质量平衡法(CMB)和Unmix等方法不同,主要区别是对不确定性参数采用了不同取值方法,其次是对原始数据中的不确定性的反映存在不同。综上所述,PMF模型已经在大气颗粒物、土壤重金属和多环芳烃(PAHs)等的应用中相对广泛,但其在其他环境介质中的除上述讨论污染物以外的源解析中仍需要进一步深入探究。 展开更多
关键词 污染源解析 受体模型 PMF模型 研究进展 应用前景
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神经复元方通过激活雄激素受体介导下游信号通路保护大鼠受损海马神经元的研究 被引量:1
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作者 廖婧彤 李文涛 +1 位作者 潘公益 蔡丽 《上海中医药杂志》 2025年第2期80-85,共6页
目的探究神经复元方通过激活雄激素受体(AR)介导长链非编码RNA生长停滞特异性转录因子5(LncRNA GAS5)调控轴影响下游相关信号通路,从而治疗卒中后抑郁(PSD)的可能机制。方法取新生大鼠的海马组织,分离出原代大鼠海马神经元。对SD大鼠给... 目的探究神经复元方通过激活雄激素受体(AR)介导长链非编码RNA生长停滞特异性转录因子5(LncRNA GAS5)调控轴影响下游相关信号通路,从而治疗卒中后抑郁(PSD)的可能机制。方法取新生大鼠的海马组织,分离出原代大鼠海马神经元。对SD大鼠给予神经复元方灌胃处理,分离血清,获得空白血清和含药血清,检测确定空白血清和含药血清的最佳处理浓度。使用100μmol/L的过氧化氢(H2O2)对大鼠海马神经元细胞处理致损伤,得到损伤模型。分做2个子实验分析验证:①子实验Ⅰ分为损伤模型+空白血清组、损伤模型+AR激动剂组、损伤模型+含药血清组、损伤模型+含药血清+AR抑制剂组4组,利用Western blot法检测各组磷酸化蛋白激酶B(p-Akt)/蛋白激酶B(Akt)、磷酸化磷脂酰肌醇3-激酶(p-PI3K)/磷脂酰肌醇3-激酶(PI3K)、脑源性神经营养因子(BDNF)、酪氨酸激酶B受体(TrkB)的蛋白表达;②子实验Ⅱ分为空白血清组、损伤模型+空白血清组、损伤模型+含药血清组3组,利用RNA免疫沉淀(RIP)法检测AR蛋白与LncRNA GAS5基因的互作关系。结果①在p-Akt/Akt、p-PI3K/PI3K、BDNF、TrkB的蛋白表达方面,与损伤模型+空白血清组比较,损伤模型+AR激动剂组和损伤模型+含药血清组上述蛋白显著上升(P<0.05);与损伤模型+含药血清组比较,损伤模型+含药血清+AR抑制剂组上述蛋白显著下降(P<0.05)。②RIP结果显示,AR蛋白与LncRNA GAS5基因存在互作,LncRNA GAS5基因在调节AR的表达及其信号通路中扮演着重要的负向调控作用。结论神经复元方对H2O2诱导的SD大鼠海马神经元损伤有一定修复作用,其部分作用机制可能是神经复元方通过激活AR介导GAS5调控轴从而激活BDNF/TrkB/PI3K/Akt通路。 展开更多
关键词 卒中后抑郁 神经复元方 海马神经元 雄激素受体 大鼠模型 中药研究
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通过机器学习探究外周血相关指标对非小细胞肺癌EGFR突变及预后的预测价值研究
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作者 付书磊 温少迪 +3 位作者 张佳强 杜晓月 李茹 沈波 《中国肺癌杂志》 北大核心 2025年第2期105-113,共9页
背景与目的 表皮生长因子受体(epidermal growth factor receptor, EGFR)敏感突变是非小细胞肺癌(non-small cell lung cancer, NSCLC)靶向治疗的有效靶点之一。然而,由于部分原发组织难以获取及部分经济欠发达地区经济因素,部分患者无... 背景与目的 表皮生长因子受体(epidermal growth factor receptor, EGFR)敏感突变是非小细胞肺癌(non-small cell lung cancer, NSCLC)靶向治疗的有效靶点之一。然而,由于部分原发组织难以获取及部分经济欠发达地区经济因素,部分患者无法进行传统基因检测。本研究旨在利用非侵入性的外周血指标,建立机器学习(machine learning, ML)模型,探索NSCLC中与EGFR突变状态密切相关的生物标志物,并评估其在预后中的潜在价值。方法 回顾性地收集2016年11月至2023年5月就诊于江苏省肿瘤医院的2642例肺癌患者的临床指标,将有完整随访数据的175例NSCLC患者纳入研究。根据外周血指标构建ML模型,按照8:2的比例分为训练集和测试集。采用无监督学习算法对血液特征进行聚类,使用互信息法进行特征筛选,并设计基于Shapley值的集成学习算法,计算每个特征对于模型预测结果的贡献程度。使用受试者工作特征(receiver operating characteristic, ROC)曲线对模型预测能力进行评估。结果 通过基于Shapley值的可解释ML模型的特征提取和对预测结果的贡献度分析,筛选出前10个贡献度最高的指标,分别为:病理类型、磷、嗜酸性粒细胞、单核细胞计数、活化部分凝血活酶时间、钾、总胆红素、钠、嗜酸性粒细胞百分比及总胆固醇。本研究模型的曲线下面积(area under the curve, AUC)为0.80。此外,低血钠及病理类型为鳞癌组的患者预后较差(P<0.05)。结论 本研究构建的可解释的模型为NSCLC患者EGFR突变状态的预测提供了新方法,这对无法进行基因检测的患者的诊疗提供了较为科学的依据。 展开更多
关键词 肺肿瘤 表皮生长因子受体 机器学习 预测模型
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妊娠期糖尿病并发子痫前期风险预测模型的构建及其增益价值研究
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作者 杨娅娅 李克花 +1 位作者 周宁娜 赵敏洁 《海南医学》 2025年第21期3096-3101,共6页
目的探讨血清可溶性血管内皮生长因子受体-1(sFlt-1)、胎盘生长因子(PLGF)、Toll样受体4(TLR4)、补体因子H在构建妊娠期糖尿病(GDM)并发子痫前期(PE)风险预测模型中的增益价值。方法选取2021年11月至2024年9月漯河市中心医院收治的GDM孕... 目的探讨血清可溶性血管内皮生长因子受体-1(sFlt-1)、胎盘生长因子(PLGF)、Toll样受体4(TLR4)、补体因子H在构建妊娠期糖尿病(GDM)并发子痫前期(PE)风险预测模型中的增益价值。方法选取2021年11月至2024年9月漯河市中心医院收治的GDM孕妇265例,根据是否并发PE分为PE组(n=42)与无PE组(n=223),比较两组患者的临床资料、血清sFlt-1、PLGF、TLR4、补体因子H水平,采用单因素广义估计方程(GEE)及多因素GEE拟合Logistic回归分析筛选出GDM并发PE的独立预测因子,采用R语言rms程序包构建常规预测模型和联合预测模型,采用Hosmer-Lemeshow检验模型的拟合优度,受试者工作特征(ROC)曲线评价常规预测模型和联合预测模型的预测价值,另选取83例GDM孕妇作为外部验证数据集,采用ROC曲线对预测模型在外部验证数据集中的预测价值进行评价。结果PE组孕妇的孕前体质量指数(BMI)、空腹血糖(FPG)、糖化血红蛋白(HbA1c)、总胆固醇、三酰甘油、同型半胱氨酸(Hcy)、sFlt-1、TLR4、补体因子H水平明显高于无PE组孕妇,PLGF水平则明显低于无PE组孕妇,差异均有统计学意义(P<0.05);多因素GEE拟合Logistic回归分析结果显示,孕前BMI、FPG、Hcy、sFlt-1、PLGF、TLR4、补体因子H均是GDM并发PE的独立影响因素(P<0.05);内部验证结果显示,基于常规影响因素(孕前BMI、FPG、Hcy)和sFlt-1、PLGF、TLR4、补体因子H所建立的联合预测模型的曲线下面积(AUC)为0.907(95%CI:0.866~0.949),明显高于基于常规影响因素构建的常规预测模型的AUC为0.781(95%CI:0.711~0.851,P<0.05);在外部验证数据集中,常规预测模型、联合预测模型的AUC分别为0.835(95%CI:0.729~0.940)、0.956(95%CI:0.910~1.000),联合预测模型的预测价值显著高于常规预测模型(P<0.05)。结论孕前BMI、FPG、Hcy、sFlt-1、PLGF、TLR4、补体因子H是GDM并发PE的独立影响因素,基于此所建立的联合预测模型具有较强的预测能力及较高的准确性,并较常规预测模型具有明显的增益价值,可为临床准确预测GDM并发PE风险提供更为可靠的预测工具。 展开更多
关键词 妊娠期糖尿病 子痫前期 补体因子H 可溶性血管内皮生长因子受体-1 胎盘生长因子 Toll样受体4 风险预测模型 增益价值
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成纤维细胞生长因子受体1 抑制剂对胶原诱导关节炎模型大鼠骨破坏的影响 被引量:1
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作者 韩海慧 孟晓辉 +3 位作者 徐博 冉磊 施杞 肖涟波 《中国组织工程研究》 CAS 北大核心 2025年第5期968-977,共10页
背景:课题组前期的研究表明靶向成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)可能是治疗类风湿性关节炎的有效靶点。目的:探讨FGFR1抑制剂(PD173074)对胶原诱导关节炎模型大鼠骨破坏的影响。方法:将25只雌性SD... 背景:课题组前期的研究表明靶向成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)可能是治疗类风湿性关节炎的有效靶点。目的:探讨FGFR1抑制剂(PD173074)对胶原诱导关节炎模型大鼠骨破坏的影响。方法:将25只雌性SD大鼠随机分为5组,正常对照组、模型组、甲氨蝶呤组、PD173074低剂量组、PD173074高剂量组。除正常对照组外,其余各组大鼠建立Ⅱ型胶原诱导关节炎模型。造模成功后正常组及模型组大鼠腹腔注射无菌PBS,甲氨蝶呤组药物注射剂量为1.04 mg/kg,PD173074低剂量组和高剂量组药物注射剂量分别为5,20 mg/kg,1次/周。给药4周后取材,观察大鼠临床症状以及关节肿胀情况,踝关节Micro-CT三维重建及分析,观察踝关节病理变化,检测关节周围血管生成情况及核因子κB受体活化因子配体的表达,检测关节滑膜中p-FGFR1、血管内皮生长因子A、抗酒石酸酸性磷酸酶的表达,观察肝、脾、肾病理变化并计算肝、脾、肾指数。结果与结论:①PD173074能够减轻模型大鼠踝关节临床症状及关节肿胀,延缓骨质丢失,改善骨结构,减轻关节滑膜侵袭以及软骨骨侵蚀,降低关节周围破骨细胞数量,抑制关节滑膜组织中的血管生成,降低核因子κB受体活化因子配体的表达,抑制FGFR1磷酸化蛋白、抗酒石酸酸性磷酸酶和血管内皮生长因子A的蛋白表达。②大鼠肝、脾、肾病理观察表明经过PD173074治疗后无明显的毒副作用。③研究证明了FGFR1抑制剂能够延缓Ⅱ型胶原诱导关节炎模型大鼠关节炎症及骨破坏的进展,并抑制血管的生成。初步验证了PD173074在Ⅱ型胶原诱导关节炎模型中的治疗作用,其可能是通过抑制FGFR1磷酸化发挥作用,为寻找类风湿性关节炎新的治疗靶点提供了方向。 展开更多
关键词 类风湿关节炎 PD173074 成纤维细胞生长因子受体1 胶原诱导型关节炎 动物模型 骨破坏 血管生成
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基于同源建模-分子对接筛选的五味子“酸味”成分
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作者 冯石卜 张婷 +8 位作者 康惠丽 姜祎 张化为 宋小妹 颜永刚 谢允东 张东东 李玉泽 邓翀 《陕西中医药大学学报》 2025年第3期95-100,共6页
目的采用同源建模与分子对接技术预测南五味子中的“酸味”成分。方法利用同源建模的方法构建酸味受体PKD2L1的三维结构模型,通过Discovery Studio软件将南五味子中125种化学成分与酸味受体进行对接,将对接分数较好的活性成分与核心靶... 目的采用同源建模与分子对接技术预测南五味子中的“酸味”成分。方法利用同源建模的方法构建酸味受体PKD2L1的三维结构模型,通过Discovery Studio软件将南五味子中125种化学成分与酸味受体进行对接,将对接分数较好的活性成分与核心靶点进行可视化分析。结果发现南五味子中38种化学成分对接分数较高,其中木脂素类化合物33种,三萜类化合物3种,甾醇类化合物1种,脂肪酸化合物1种。推测“酸味”化学成分群主要为木脂素类化合物,即南五味子中木脂素类化学成分能调控酸味受体并对二型糖尿病(typeⅡdiabetes,T2DM)产生防治作用。结论研究发现南五味子“酸味”化学成分群主要为木脂素类成分,为揭示“酸味”中药的物质基础提供方法学参考。 展开更多
关键词 南五味子 酸味受体 分子对接 同源建模 化学成分
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基于人源化IGF1R小鼠的呼吸道合胞病毒感染肺炎动物模型的构建及应用 被引量:2
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作者 杨晓微 谢丹 +9 位作者 李舒冉 包蕾 耿子涵 刘宪 崔梦瑶 王雅欣 曹姗 崔晓兰 孙静 郭姗姗 《中国实验方剂学杂志》 北大核心 2025年第21期48-53,共6页
目的:构建适用于临床前研究的呼吸道合胞病毒(RSV)感染肺炎动物模型。方法:通过细胞病变效应(CPE)观察RSV对4种细胞系的毒力,并计算半数组织培养物感染量(TCID50)。将20只BALB/c小鼠随机分为正常组、模型组;6只BALB/c-hIGF1R小鼠作为人... 目的:构建适用于临床前研究的呼吸道合胞病毒(RSV)感染肺炎动物模型。方法:通过细胞病变效应(CPE)观察RSV对4种细胞系的毒力,并计算半数组织培养物感染量(TCID50)。将20只BALB/c小鼠随机分为正常组、模型组;6只BALB/c-hIGF1R小鼠作为人源化IGF1R模型组。除正常组外,各组于第1、3天滴鼻感染RSV,建立病毒性肺炎模型,通过检测脏器指数、外周血淋巴细胞百分比、肺部病理学与影像学、肺部病毒载量,评价基于人源化胰岛素样生长因子1受体(IGF1R)小鼠的RSV感染肺炎动物模型的构建成果。并将10只BALB/c小鼠作为正常组,32只BALB/c-hIGF1R小鼠随机分为人源化IGF1R模型组,利巴韦林组(82.5 mg·kg^(-1)·d^(-1)),连花清瘟高、低剂量组(3.3、1.65 mg·kg^(-1)·d^(-1)),每组8只。检测利巴韦林和连花清瘟颗粒干预后的小鼠肺组织病毒载量,将该模型应用到抗RSV药物评价中。结果:人源化IGF1R模型组肺部可见大片的实变影和弥漫性磨玻璃影,肺体积显著增大(P<0.01);肺指数显著增高(P<0.01),脾指数和胸腺指数均显著减小(P<0.01);CD3^(+)、CD4^(+)T细胞百分比明显减少(P<0.05);肺组织血管周围大量炎症、瘀血,以淋巴细胞为主,血管内膜部分脱落,有少量嗜酸细胞;采用RSV感染BALB/c-hIGF1R小鼠后,小鼠肺组织中病毒核酸表达明显增加,与正常组比较差异具有统计学意义(P<0.01);利巴韦林组和连花清瘟高、低剂量组病毒核酸表达量均明显降低,与人源化IGF1R模型组比较差异具有统计学意义(P<0.01)。结论:人源化IGF1R小鼠具有较强的感染RSV的特性,基于人源化IGF1R小鼠的RSV感染肺炎动物模型构建成功,该模型适用于抗RSV药物评价。 展开更多
关键词 呼吸道合胞病毒 动物模型 胰岛素样生长因子1受体 肺部影像学
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