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On the Range of Action of Adult Culex pipiens s.l.
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作者 Maria da Conceição Proença Maria Teresa Rebelo 《Journal of Biosciences and Medicines》 2024年第3期113-121,共9页
Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans... Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans, such as dengue, yellow fever, chikungunya, West Nile virus, encephalitis and malaria, among many others that are less common. In terms of morbidity and mortality caused by vector-borne diseases, mosquitoes are the most dangerous animals for humanity and, although they also play a role in the ecosystem as a food source for other organisms, their importance for public health cannot be overlooked. As highly efficient vectors, they put more than three billion people at risk, mainly in tropical and subtropical regions as well as in Europe, since heat waves and flooding are becoming more frequent and severe, and summers are getting longer and warmer, accelerating mosquito development, biting rates, and the incubation of the pathogens within their bodies. Female mosquitoes bite to acquire proteins for the development of their ovaries and eggs and, in the process, acquire pathogens and/or parasites from one vertebrate host and transmit them to another, usually after a short period of replication. Three of their four life stages are lived in still freshwater, so it is crucial to understand their range of action when they reach adulthood and leave the water, in order to plan and implement local prevention measures. A set of georeferenced abundance data collected in mainland Portugal over seven years was linked to cartographed water bodies in a geographic information system to estimate the distances at which Culex pipiens s.l. had a significant presence, with criteria based on the size of the catches. The result allows for an estimate of the fly range of those mosquitoes, which can be used to focus countermeasures. 展开更多
关键词 Mosquito Fly Distance Vector-Borne Diseases Culex pipiens s.l. Geographic Information Systems
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藜科植物S.L多糖抗病毒作用机理初步研究 被引量:8
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作者 田兆丰 裘季燕 +3 位作者 刘伟成 李永丹 魏荣 曾燕舞 《华北农学报》 CSCD 北大核心 2006年第5期108-112,共5页
对从藜科植物中提取的、具有诱导抗病毒作用的S.L多糖的作用机理做了初步的研究。首先将S.L多糖抽提液喷施烟草,探究S.L多糖诱导烟草对烟草花叶病毒(TMV)产生抗性的最佳时间。结果表明,用S.L多糖诱导植株产生的抗性在5 d左右达到最大,5 ... 对从藜科植物中提取的、具有诱导抗病毒作用的S.L多糖的作用机理做了初步的研究。首先将S.L多糖抽提液喷施烟草,探究S.L多糖诱导烟草对烟草花叶病毒(TMV)产生抗性的最佳时间。结果表明,用S.L多糖诱导植株产生的抗性在5 d左右达到最大,5 d之后抗病性随着时间的推移而减弱。在接种病毒前用S.L多糖对烟草幼苗进行喷施,然后于接种当天及接种后不同时间对各处理的同位等量叶片测定在总蛋白含量、过氧化物酶活性及同工酶图谱上的差异。研究发现,各处理的总蛋白含量均有所增加,且高于对照,并都于接种后的第9 d达到最大值。各处理的过氧化物酶活性在接种病毒初期均高于对照,但5 d后对照的酶活性超过处理,高峰较处理提前到来,且峰值略大于处理。在同工酶谱上,病毒接种后5 d,处理的酶带比对照浓且多了1条。5 d之后,二者的酶谱变得基本相同。到接种后10 d测定,结果相反,对照比处理的酶带浓。 展开更多
关键词 s.l多糖 TMV 诱导抗性
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基于ASTER与TM数据的黑河流域中游旱区典型区域植被覆盖度研究 被引量:1
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作者 赵岩 王思远 +2 位作者 毕海芸 王辉 殷慧 《测绘通报》 CSCD 北大核心 2013年第4期4-7,共4页
以2000年、2001年和2008年黑河流域ASTER与TM影像为主要数据源,综合RS和GIS技术,通过在ENVI平台编写IDL程序,并利用6S模型进行大气校正,反演得到归一化植被指数(NDVI)。在此基础上定性分析该区域植被覆盖度空间分布格局,定量研究2001—2... 以2000年、2001年和2008年黑河流域ASTER与TM影像为主要数据源,综合RS和GIS技术,通过在ENVI平台编写IDL程序,并利用6S模型进行大气校正,反演得到归一化植被指数(NDVI)。在此基础上定性分析该区域植被覆盖度空间分布格局,定量研究2001—2008年植被覆盖度的变化情况,并对其成因进行探讨;同时对比ASTER和TM传感器进行植被覆盖度反演结果,并结合研究区域土地覆盖调查数据资料,说明ASTER传感器较TM传感器在局部土地利用调查方面更具有优势。 展开更多
关键词 黑河流域 aster与TM影像 IDL 6S NDVI 植被覆盖度
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S.L.安德森风景园林设计哲学及艺术表现手法探析 被引量:3
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作者 杨滨章 《中国园林》 北大核心 2013年第4期73-79,共7页
S.L.安德森是目前在世界范围内享有盛誉的少数丹麦风景园林师之一,其设计作品因具有新颖独特、温馨浪漫、地域鲜明、人文情怀等特点而备受人们喜爱。通过对其设计哲学和艺术表现手法的探讨,有助于人们理解他的作品。其设计哲学可以概括... S.L.安德森是目前在世界范围内享有盛誉的少数丹麦风景园林师之一,其设计作品因具有新颖独特、温馨浪漫、地域鲜明、人文情怀等特点而备受人们喜爱。通过对其设计哲学和艺术表现手法的探讨,有助于人们理解他的作品。其设计哲学可以概括为运用人本理念促进社会和谐,运用乡土元素促进文化传承,运用艺术创新促进景观发展,运用可持续原则促进品质提升;而表现手法则可以概括为简洁的设计形式、多样的功能空间、丰富的感观体验和精致的细部处理。 展开更多
关键词 风景园林 S L 安德森 设计哲学 艺术表现 探析
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K-L变换与NDBI指数法提取ASTER影像城市用地信息的比较 被引量:4
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作者 秦鹏 陈健飞 《测绘与空间地理信息》 2008年第5期33-36,共4页
运用K-L变换和NDBI(Normalized Difference Barren Index)指数法,对试验区——沧州市及其周边地区的ASTER遥感影像进行处理,然后分别对两种方法处理后的图像采用最小距离法监督分类,提取城市用地信息,并对分类后的图像进行对比,结果表明... 运用K-L变换和NDBI(Normalized Difference Barren Index)指数法,对试验区——沧州市及其周边地区的ASTER遥感影像进行处理,然后分别对两种方法处理后的图像采用最小距离法监督分类,提取城市用地信息,并对分类后的图像进行对比,结果表明:NDBI指数法对城市用地信息提取的效果较好。 展开更多
关键词 aster影像 归一化裸露指数 K-L变换 最小距离分类法 沧州市
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ENA多肽抗体谱在S.L.E诊断中的意义
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作者 李红文 罗双利 +2 位作者 赵志兰 张德正 王向中 《中国卫生检验杂志》 CAS 2000年第6期723-724,共2页
关键词 ENA多肽抗体谱 s.l.E 诊断 系统性红斑狼疮
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Molecular phylogeny of Solms-laubachia(Brassicaceae) s.l.,based on multiple nuclear and plastid DNA sequences,and its biogeographic implications 被引量:7
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作者 Ji-Pei YUE Hang SUN +3 位作者 David A. BAUM jian-Hua LI Ihsan A. AL-SHEHBAZ Richard REE 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期402-415,共14页
The Hengduan Mountains region of south-west China is a noted biodiversity,hotspot, but the geographic origins and historical assembly of its rich endemic flora, including the sky-island species ofSolms-laubachia Musch... The Hengduan Mountains region of south-west China is a noted biodiversity,hotspot, but the geographic origins and historical assembly of its rich endemic flora, including the sky-island species ofSolms-laubachia Muschl. (Brassicaceae), have been little studied. Previous molecular studies on the phylogeny of Solms-laubachia showed it to be paraphyletic, leading to considerable expansion not only of its taxonomic limits, but also its geographic range, with the inclusion of taxa from outside the Hengduan region. However, these studies provided little resolution of interspecific relationships, preventing inferences about historical biogeography within the clade. In the present study, new sequence data from two nuclear genes (LEAFY and G3pdh) and two chloroplast intergenic spacers (petN-psbM and psbM-trnD) were combined with existing markers to increase phylogenetic signals. Phaeonychium villosum (Maxim.) Al-Shehbaz was found to be nested within Solms-laubachia s.l. In general, phylogenetic relationships appear to be a good predictor of geography, with the Hengduan Mountain endemics embedded in a paraphyletic grade of species from the western Himalayas and central Asia, but they also imply morphological homoplasy, lncongruence was detected between the nuclear and chloroplast gene trees, perhaps resulting from incomplete lineage sorting of ancestral polymorphisms. The crown age ofSolms-laubachia s.l. was estimated to be approximately 1.42-3.68 mya, using Bayesian relaxed molecular clock analysis. Historical biogeographic analysis using a parametric dispersalextinction-cladogenesis model inferred central Asia and the western Himalayas as most probable ancestral range of Solms-laubachia s.l., and estimated higher rates of eastward expansion than westward during the diversification of descendant lineages. In summary, our results suggest that Solms-laubachia s.l. originated during the Pliocene in central Asia, and subsequently migrated eastward into the Hengduan Mountains, colonizing sky-island, alpine scree-slope habitats that may have provided novel ecological opportunity and accelerated speciation, ultimately establishing this region as the present center of diversity of the genus. 展开更多
关键词 BIOGEOGRAPHY Brassicaceae Hengduan Mountains PHYLOGENY Solms-laubachia s.l.
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A NEW TRITERPENE GLYCOSIDE FROM THE ROOT OF ASTER TATARICUS L. F 被引量:1
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作者 Dong Liang CHENG, Yu SHAO Institute of Organic Chemisty, University, Lanzhou, 730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第11期889-890,共2页
A new oleanane-rype triterpene glycoside, Aster saponin G, was isolated from the root of Aster tataricus L.F. (Compositae). and its structure was elucidated on the basis of spectral and chemical methods. Aster saponin... A new oleanane-rype triterpene glycoside, Aster saponin G, was isolated from the root of Aster tataricus L.F. (Compositae). and its structure was elucidated on the basis of spectral and chemical methods. Aster saponin G is 3-0[α-L-arabinopyranosyl-(1→6)-β-D-glucopyranosyl]-2β,3β, 16α-trihydroxyolean-12-en-28-oic acid(asterogenic acid) 28-0-[β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyl] ester 展开更多
关键词 aster IC A NEW TRITERPENE GLYCOSIDE FROM THE ROOT OF aster TATARICUS L ROOT
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OLIGOPEPTIDES FROM THE ROOTS OF ASTER TATARICUS L. f.
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作者 Dong Liang CHEN Yu SHAO +1 位作者 Yu Xin CUI R. Hartman Institute of Organic Chemistry, Stae Key Laboratory of Applied Organic Chemistry, Lanzou University, Lanzou, 730000 Institute of Physiological Chemistry, Bonn University, Bonn, Germany 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第7期605-608,共4页
Two new oligopeptides, Asterin A and B, have been isolated from the roots of Aster tataricus L. f., and their structures were elucidated on the basis of spectroscop- ic, chemical and enzymatic methods.
关键词 aster OLIGOPEPTIDES FROM THE ROOTS OF aster TATARICUS L
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Molecular phylogeny of the genus Corchorus(Grewioideae,Malvaceae s.l.) based on nuclear rDNA ITS sequences
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作者 Solomon Benor 《The Crop Journal》 SCIE CAS CSCD 2018年第5期552-563,共12页
A molecular phylogenetic analysis of the genus Corchorus(Grewioideae,Malvaceae s.l.)is presented,based on sequences of the nuclear ribosomal DNA internal transcribed spacer(ITS)region for 144 accessions representing 4... A molecular phylogenetic analysis of the genus Corchorus(Grewioideae,Malvaceae s.l.)is presented,based on sequences of the nuclear ribosomal DNA internal transcribed spacer(ITS)region for 144 accessions representing 47 species.Several other genera from the subfamily Grewioideae,namely Pseudocorchorus,Triumfetta,Sparrmannia,Entelea,and Grewia,were included as outgroups.The monophyly of the genus was well supported by all phylogenetic analyses(maximum likelihood,Bayesian approaches,and parsimony),and Corchorus was divided into four major clades.The majority of African species formed a statistically highly supported and distinct clade separated from the other pantropically distributed species.Several endemic species from Australia,New Caledonia,and tropical America were nested within this distinct clade,indicating dispersal from Africa to the rest of the pantropics.Based on the taxa included in this study,the two cultivated species(C.olitorius and C.capsularis)shared a common ancestry with wild species of C.africanus,C.brevicornatus,C.pseudocapsularis,C.pseudo-olitorius,C.urticifolius,C.pilosus,C.orinocensis,and C.cunninghamii.Pseudocorchorus,previously considered an accepted genus,was nested within the genus Corchorus and shared a common ancestry especially with C.depressus and C.siliquosus.Based on morphological and anatomical similarity as well as the results of the present molecular findings,inclusion of the six Pseudocorchorus species into Corchorus is proposed,with Pseudocorchorus as a synonym of Corchorus.Of the included outgroup taxa,Triumfetta is the closest sister to Corchorus,while the common ancestor of Corchorus/Pseudocorchorus,Triumfetta,Sparrmannia,and Entelea is Grewia.A further phylogenetic study with more taxa mainly from Australia,together with additional molecular markers and morphological investigation,would help to test the hypothesis on the biogeography and growth form evolution of the genus Corchorus. 展开更多
关键词 Corchorus JUTE Malvaceae s.l. PHYLOGENY Pseudocorchorus
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New and Unusual Cat's Eyes and Asteriated Gems
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作者 Martin P.Steinbach Lore Kiefert Jeanette Fiedler 《宝石和宝石学杂志(中英文)》 CAS 2022年第1期1-11,共11页
The article describes 6 types of gemstones which show phenomena such as chatoyancy and asterism.The gemstones have not been described before,either because they come from new sources,or because the phenomenon has not ... The article describes 6 types of gemstones which show phenomena such as chatoyancy and asterism.The gemstones have not been described before,either because they come from new sources,or because the phenomenon has not been seen before in the type of gemstone described.Gems from the new sources are star garnet from the Karelia Province in Russia,and star garnet from the Jiangsu Province in China.Grandidierite usually does not show a cat’s eye effect,but the two described samples display a weak cat’s eye.An unusual white quartz from Brazil with a sharp cat’s eye is described,as well as a star sapphire with two differently coloured stars on each side of the cabochon,as well as a trapiche-type quartz.The stones were tested with gemmological,microscopic,and advanced techniques and the results are presented. 展开更多
关键词 cat’s eye star asterism chatoyancy QUARTZ grandidierite SAPPHIRE GARNET
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Climatic and Physiographic Variables to Evaluate Culex pipiens s.l. Risk and Habitat
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作者 Maria da Conceição Proença Maria João Alves Maria Teresa Rebelo 《Journal of Geoscience and Environment Protection》 2022年第8期1-8,共8页
Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens s.l. collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic para... Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens s.l. collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic parameters are evaluated. This work is one of the results of a long-term surveillance program of pernicious insects that act as vectors of various diseases;its focus is on the possibility of prevention that can be achieved with abundance data. The focus on Culex pipiens is justified by its abundance and its competence as a vector for numerous health issues. The cumulative distribution of monthly captures by each meteorological parameter allows to compute thresholds corresponding to mosquito massive presence related to 90% of the captures. Using the weather parameters measured in the network of weather stations across the country, a monthly average of each parameter of interest (temperature, humidity, etc.) is computed and an interpolation of the results is made to produce raster maps corresponding to each month. The previously obtained thresholds are applied to each map, producing spatial masks with the relevant zones for each parameter. The intersection of the various masks for each month shows the most densely populated area of Culex, and the ensemble allows us to observe the evolution of mosquito presence through the critical season, which is from May to October at these latitudes. In parallel, mosquito abundance data are related to physiographic parameters. The relative distribution of female mosquitoes across land cover types in each month allows identifying which classes and seasons are most relevant. Orthometric altitude related to the presence of 90% of the catches shows the limits reached by mosquitoes in each month. The results are applied to the previously obtained climate envelopes, delimiting critical areas where the level of risk of transmission of the pathogens for which Culex pipiens is a competent vector is high and countermeasures should be concentrated, allowing its planning, and targeting on a monthly basis. The described procedure can be used with other relevant vectors in any region of the world, whenever abundance data is available. 展开更多
关键词 Vector-Borne Diseases Transmission Risk Culex pipiens s.l. GIS Global Changes
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Efficacy of the Microbial Larvicide VectoMax<sup>®</sup>G against <i>Anopheles gambiae</i>s.l. and <i>Culex</i>spp. Larvae under Laboratory and Open Field Trial Experiments in the City of Yaoundé, Cameroon
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作者 Kopya Edmond Foko Dadji Gisele Aurelie +8 位作者 Sonhafouo-Chiana Nadège Bamou Roland Djamouko-Djonkam Landre Talipouo Abdou Delogko Serges Njiokou Flobert Awono-Ambene Parfait Wondji Charles Sinclair Antonio-Nkondjio Christophe 《Advances in Entomology》 2022年第1期34-51,共18页
<strong>Background: </strong><span><span><span><span>With the rapid expansion of insecticide resistance limiting the effectiveness of insecticide-based vector control interventions,... <strong>Background: </strong><span><span><span><span>With the rapid expansion of insecticide resistance limiting the effectiveness of insecticide-based vector control interventions, integrated control strategies associating larviciding could be appropriate to improve current control efforts. The present experimental study assesses laboratory and field efficacy of the larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> on <i>Anopheline</i> and <i>Culicine</i> larval stages in Yaoundé. <strong>Methods:</strong> The effect of the larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G,</span></span></span></span><span><span><span><span> a combination of <i>Bacillus</i><span> <i>thuringiensis</i> var. <i>israelensis</i> </span>(<i>Bti</i>) </span></span></span></span><span><span><span><span>and <i>Bacillus</i> <i>sphaericus</i> (<i>Bs</i>),</span></span></span></span><span><span><span><span> on larval development was assessed during both laboratory and open field trial experiments. Laboratory experiments permitted the evaluation of five different concentrations with four replicates/experiments. Laboratory experiments were conducted with <i>Anopheles</i> <i>coluzzii</i> “Ngousso” and <i>Culex</i> <i>quinquefasciatus</i> laboratory strains. Open field trials were conducted using </span></span></span></span><span><span><span><span>sixteen plastic containers with a diameter of 0.31 m buried in an array of four rows with 4 containers each. Distance between rows and between containers in a row was 1 meter. This experiment permitted to </span></span></span></span><span><span><span><span>test the effect of the microbial larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> under operational application conditions on field mosquito populations. <strong>Results:</strong> <span>The time to induce 100% mortality after exposure to serial concentrations of the larvicide varied according to the dose from 4 - 12 hours for <i>An.</i> <i>coluzzii</i> and 6 - 9 hours for <i>Cx.</i> <i>quinquefasciatus</i> in laboratory experiments. Measurements of the</span> residual activity indicated that all </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> concentrations were still active after 35 days and killed 86</span></span></span></span><span><span><span><span>% </span></span></span></span><span><span><span><span>-</span></span></span></span><span><span><span><span> </span></span></span></span><span><span><span><span>100% of larvae. Lethal dose of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> killing 50% of larvae was estimated at 5.24 × 10<sup>-8</sup> mg/m<sup>2</sup> for <i>An.</i> <i>coluzzii</i> and 1.25 × 10<sup>-8</sup> mg/m<sup>2</sup> for <i>Cx.</i> <i>quinquefasciatus</i>. The lethal concentration inducing 95% mortality was estimated at 3.13 × 10<sup>-7</sup> mg/m<sup>2</sup> for <i>An.</i> <i>coluzzii</i> and 2.5 × 10<sup>-8</sup> <span>mg/m<sup>2</sup> for <i>Cx.</i> <i>quinquefasciatus</i>. Open field trials tests indicated that </span>sub-lethal concentrations of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> successfully killed 100% <i>An.</i> <i>gambiae</i> s.l. larvae within 24 hours, while with <i>Culex</i> spp. larvae, 100% mortality was recorded after 48 hours post-treatment. Natural recolonization of water containers by larvae was recorded between 3 and 6 days respectively after the treatment with sublethal doses. Late instar larvae were recorded 5 and 6 days after treatment. When the jars were treated with reference dosage or supra doses of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G,</span></span></span></span><span><span><span><span> recolonization of water containers was observed six days after treatments. No pupae of both species were found 6 and 7 days post-treatment. <strong>Conclusions:</strong> The study indicated high efficacy of the microbial larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> against <i>Anopheline</i> and <i>Culex</i> larvae. Microbial larvicides such as </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>&reg;</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> could be appropriate for controlling mosquito population particularly in areas experiencing high insecticide resistance or outdoor biting mosquitoes.</span></span></span></span> 展开更多
关键词 VectoMax®G Bacillus thuringiensis var. israelensis Bacillus sphaericus Anopheles gambiae s.l. Culex Mosquitoes Yaoundé Camreroon
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慢性阻塞性肺疾病患者血清CatS、CatL、CatB与炎性因子、CAT评分及预后的相关性研究
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作者 王辉 康肖菲 +1 位作者 郭立娟 冯淬灵 《西部医学》 2024年第12期1798-1802,共5页
目的探究急性加重期慢性阻塞性肺疾病(AECOPD)患者血清组织蛋白酶L(CatL)、组织蛋白酶S(CatS)、组织蛋白酶B(CatB)与炎性因子(IL-8、IL-10、TNF-α、CRP)、COPD评估测试(CAT)评分及预后的关系。方法选择2022年1月—12月河北大学附属医... 目的探究急性加重期慢性阻塞性肺疾病(AECOPD)患者血清组织蛋白酶L(CatL)、组织蛋白酶S(CatS)、组织蛋白酶B(CatB)与炎性因子(IL-8、IL-10、TNF-α、CRP)、COPD评估测试(CAT)评分及预后的关系。方法选择2022年1月—12月河北大学附属医院收治的224例AECOPD患者为病例组,同期选择健康体检肺功能正常者62例为对照组。比较两组血清CatS、CatL、CatB、CRP、IL-8、IL-10、TNF-α水平及CAT评分;采用Pearson检验分析AECOPD患者血清CatS、CatL、CatB与炎性因子和CAT评分的相关性。对224例AECOPD患者随访28 d,统计死亡例数,比较生存组与死亡组临床资料及各实验室指标,采用Logistic回归模型分析AECOPD预后的影响因素。结果病例组血清CatB低于对照组(P<0.05),CatS、CatL高于对照组(P<0.05);病例组血清IL-10低于对照组(P<0.05),CRP、IL-8、TNF-α、CAT显著高于对照组(P<0.05)。Pearson检验显示,AECOPD患者血清CatS、CatL与CRP、IL-8、TNF-α、CAT评分呈正相关(P<0.05),与IL-10呈负相关(P<0.05);血清CatB与CRP、IL-8、TNF-α、CAT评分呈负相关(P<0.05),与IL-10呈正相关(P<0.05)。224例AECOPD患者中,随访28 d死亡39例。生存组和死亡组性别、年龄、COPD病程、白细胞计数、白蛋白、饮酒史、饮酒史、高血压占比、糖尿病占比、冠心病占比差异无统计学意义(P>0.05);与生存组比较,死亡组机械通气占比、PaCO_(2)、CatS、CatL升高(P<0.05),PaO_(2)、CatB显著降低(P<0.05)。Logistic回归模型显示,机械通气、PaCO_(2)、CatS、CatL是AECOPD预后的危险因素(P<0.05),PaO_(2)、CatB为其保护因素(P<0.05)。结论AECOPD患者血清CatS、CatL、CatB与炎性因子、CAT评分及预后关系密切,三者水平检测有助于评估AECOPD病情和预后。 展开更多
关键词 急性加重期慢性阻塞性肺疾病 组织蛋白酶L 组织蛋白酶S 组织蛋白酶B 炎性因子 CAT评分 预后
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面向L5/S1微创椎间盘射频消融术的多约束最优穿刺路径规划算法
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作者 刘虎 苏志海 +5 位作者 黄成颉 赵磊 陈扬帆 周宇佳 吕海 冯前进 《南方医科大学学报》 CAS CSCD 北大核心 2024年第9期1783-1795,共13页
目的为有效减少L5/S1微创椎间盘射频消融术中因医师操作熟练度差异导致的治疗效果波动,实现对消融针穿刺路径风险的精确量化评估。方法基于自主研发的深度神经网络DWT-UNet,将L5/S1节段的MR图像精准分割为7个关键结构:L5椎骨,S1椎骨,髂... 目的为有效减少L5/S1微创椎间盘射频消融术中因医师操作熟练度差异导致的治疗效果波动,实现对消融针穿刺路径风险的精确量化评估。方法基于自主研发的深度神经网络DWT-UNet,将L5/S1节段的MR图像精准分割为7个关键结构:L5椎骨,S1椎骨,髂骨,L5/S1节段的椎间盘、神经根、硬脊膜和皮肤。基于上述分割结果,3D建模穿刺路径的规划环境。针对穿刺的临床准则提出了6个硬性约束和6个软性约束,将医师经验通过层次分析算法量化为权重添加到穿刺路径风险函数中以提升对个例的适应性。通过提出的皮肤进针点采样子算法、Kambin三角投影面积子算法,结合层次分析算法,并运用光线追踪、CPU多线程处理和GPU并行计算等多种技术,计算出一条既符合临床硬性约束条件,又能使软性约束条件综合达到最优的穿刺路径。结果医师团队对算法规划的21例消融针穿刺路径进行主观评估,结果显示所有路径均满足临床基本要求(及格率100%),且95.24%的路径被评为优秀或良好。在与医师规划结果的对比中,算法在D_(Ilium)、D_(S1)和Depth等3个指标上有不同程度的下降(P<0.05),在D_(Dura)、D_(L5)、D_(N5)和A_(Kambin)等4个指标上有较大提升(P<0.05)。算法规划21例的平均时间为7.97±3.73 s,而医师传统规划普遍需耗时10 min以上。结论本研究提出的多约束最优穿刺路径规划算法为L5/S1节段的微创椎间盘射频消融术提供了一种一站式的解决方案。经过严谨的临床评价和实验验证,该算法显示出独特的优势和广阔的临床应用潜力。 展开更多
关键词 微创椎间盘射频消融术 L5/S1 Kambin三角 路径规划
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基于外部气相沉积的S+C+L波段低色散斜率大有效面积非零色散位移光纤的设计与制备
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作者 查健江 王元达 +3 位作者 何学荣 侯伟 王敬胜 文建湘 《光子学报》 EI CAS CSCD 北大核心 2024年第2期52-63,共12页
针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第... 针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第一芯层的半径比,探究了其对光纤衰减、色散斜率和有效面积等参数的影响。研究发现,当第一芯层的相对折射率逐渐增大且第二芯层与第一芯层半径比逐渐减小时,零色散波长和有效面积逐渐减小。当第一芯层的相对折射率在0.52%~0.53%,芯层半径比在2.6~2.7时,光纤的有效面积接近70μm^(2),零色散波长在1420 nm附近,在1550 nm波段的色散系数大于8 ps·nm^(-1)·km^(-1),色散斜率为0.059 ps·nm^(-2)·km^(-1),可以较好地抑制传输过程中光非线性效应,满足长途干线网与城域网的使用要求。 展开更多
关键词 光纤通信 非零色散位移光纤 外部气相沉积工艺 S+C+L波段 低色散斜率 大有效面积 波分复用
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大蒜辣素在大鼠体内转化产物S-烯丙基巯基-L-半胱氨酸的鉴别
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作者 吴莹莹 史荣梅 +4 位作者 李世颖 刘睿婷 宋百灵 马雪红 李新霞 《新疆医科大学学报》 CAS 2024年第9期1281-1287,共7页
目的鉴别大鼠给药后大蒜辣素体内转化产物S-烯丙基巯基-L-半胱氨酸,探讨血浆和皮肤组织中S-烯丙基巯基-L-半胱氨酸的变化情况。方法取SD大鼠,雌雄各半,体重(200±20)g,随机分为8组,分别为空白组及给药后不同时间组,每组每个时间点采... 目的鉴别大鼠给药后大蒜辣素体内转化产物S-烯丙基巯基-L-半胱氨酸,探讨血浆和皮肤组织中S-烯丙基巯基-L-半胱氨酸的变化情况。方法取SD大鼠,雌雄各半,体重(200±20)g,随机分为8组,分别为空白组及给药后不同时间组,每组每个时间点采用6只大鼠,涂抹大蒜软膏于大鼠背部,分别于0、5、10、15、20、25、30、60 min依次取血液和皮肤组织,UPLC-MS/MS鉴定血液和皮肤组织中大蒜辣素的转化产物S-烯丙基巯基-L-半胱氨酸及变化情况。结果大蒜辣素与半胱氨酸反应产生S-烯丙基巯基-L-半胱氨酸,30 min即可反应90%以上。血浆中转化产物S-烯丙基巯基-L-半胱氨酸在4 h内稳定。UPLC-MS/MS鉴定并确定了皮肤组织和血浆样品大蒜辣素与内源性半胱氨酸的反应产物S-烯丙基巯基-L-半胱氨酸,给予大蒜软膏30 min内血浆和皮肤中S-烯丙基巯基-L-半胱氨酸的浓度逐步增大,60 min时含量降低。结论大蒜辣素可与血浆和组织中的内源性半胱氨酸快速反应,本研究将为大蒜辣素的后续研究提供重要依据。 展开更多
关键词 超高效液相色谱-串联质谱 大蒜辣素 半胱氨酸 S-烯丙基巯基-L-半胱氨酸
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Unveiling DNA methylation in Alzheimer’s disease:a review of array-based human brain studies 被引量:1
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作者 Victoria Cunha Alves Eva Carro Joana Figueiro-Silva 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2365-2376,共12页
The intricacies of Alzheimer’s disease pathogenesis are being increasingly illuminated by the exploration of epigenetic mechanisms,particularly DNA methylation.This review comprehensively surveys recent human-centere... The intricacies of Alzheimer’s disease pathogenesis are being increasingly illuminated by the exploration of epigenetic mechanisms,particularly DNA methylation.This review comprehensively surveys recent human-centered studies that investigate whole genome DNA methylation in Alzheimer’s disease neuropathology.The examination of various brain regions reveals distinctive DNA methylation patterns that associate with the Braak stage and Alzheimer’s disease progression.The entorhinal cortex emerges as a focal point due to its early histological alterations and subsequent impact on downstream regions like the hippocampus.Notably,ANK1 hypermethylation,a protein implicated in neurofibrillary tangle formation,was recurrently identified in the entorhinal cortex.Further,the middle temporal gyrus and prefrontal cortex were shown to exhibit significant hypermethylation of genes like HOXA3,RHBDF2,and MCF2L,potentially influencing neuroinflammatory processes.The complex role of BIN1 in late-onset Alzheimer’s disease is underscored by its association with altered methylation patterns.Despite the disparities across studies,these findings highlight the intricate interplay between epigenetic modifications and Alzheimer’s disease pathology.Future research efforts should address methodological variations,incorporate diverse cohorts,and consider environmental factors to unravel the nuanced epigenetic landscape underlying Alzheimer’s disease progression. 展开更多
关键词 Alzheimer’s disease ANK1 BIN1 DNA methylation epigenome-wide association studies HOXA3 MCF2L RHBDF2
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基于BiLSTM-Attention的F_(10.7)指数预测模型与中国自主数据集的应用
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作者 闫帅楠 李雪宝 +7 位作者 董亮 黄文耿 王晶 闫鹏朝 娄恒瑞 黄徐胜 李哲 郑艳芳 《空间科学学报》 CAS CSCD 北大核心 2024年第2期251-261,共11页
F_(10.7)指数是太阳活动的重要指标,准确预测F_(10.7)指数有助于预防和缓解太阳活动对无线电通信、导航和卫星通信等领域的影响.基于F_(10.7)射电流量的特性,在双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,BiLSTM... F_(10.7)指数是太阳活动的重要指标,准确预测F_(10.7)指数有助于预防和缓解太阳活动对无线电通信、导航和卫星通信等领域的影响.基于F_(10.7)射电流量的特性,在双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,BiLSTM)基础上融入注意力机制(Attention),提出了一种基于BiLSTM-Attention的F_(10.7)预报模型.在加拿大DRAO数据集上其平均绝对误差(MAE)为5.38,平均绝对百分比误差(MAPE)控制在5%以内,相关系数(R)高达0.987,与其他RNN模型相比拥有优越的预测性能.针对中国廊坊L&S望远镜观测的F_(10.7)数据集,提出了一种转换平均校准(Conversion Average Calibration,CAC)方法进行数据预处理,处理后的数据与DRAO数据集具有较高的相关性.基于该数据集对比分析了RNN系列模型的预报效果,实验结果表明,BiLSTM-Attention和BiLSTM两种模型在预测F_(10.7)指数方面具有较好的优势,表现出较好的预测性能和稳定性. 展开更多
关键词 F_(10.7)预报 双向长短时记忆网络 注意力机制 L&S数据集
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基于理性扩展热力学的L-S热声弹性理论框架
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作者 李元燮 刘财 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第2期655-687,共33页
本文基于连续介质力学和理性扩展热力学分析流程,将L-S(Lord and Shulman)热弹性理论与声弹性理论相结合,建立L-S热声弹性理论的基本框架,包括运动学、力学与热力学、本构方程与演化方程、基本场方程四部分。在运动学部分,区分了Lagrang... 本文基于连续介质力学和理性扩展热力学分析流程,将L-S(Lord and Shulman)热弹性理论与声弹性理论相结合,建立L-S热声弹性理论的基本框架,包括运动学、力学与热力学、本构方程与演化方程、基本场方程四部分。在运动学部分,区分了Lagrange描述和Euler描述,以及3种不同的状态和构形,同时针对热声弹性情况定义了两类从自然状态到初始状态的转变过程;在力学与热力学部分,给出了质量守恒定律、动量守恒定律、角动量守恒定律、能量守恒定律以及熵产不等式,从而引出经典不可逆热力学的局限性;在本构方程与演化方程部分,介绍了扩展不可逆热力学原理,并基于理性扩展热力学流程,推导了从自然状态到初始状态、从初始状态到最终状态的热声弹性本构方程与演化方程,将热流作为本构自变量并考虑了热流与应变和温度的相关性;在最后一部分给出了基本场方程的运动方程形式和适用于数值模拟的一阶速度-应力-热流-温度微分方程。 展开更多
关键词 L-S理论 热弹性 声弹性 连续介质力学 理性扩展热力学
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