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The Epidemiological, Clinical, Biological and Morphological Characteristics of Primitive Liver Cancers in Bangui 认领
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作者 Serges Magloire Camengo Police Georges Service +13 位作者 Nathalie Philomè ne Boua-Akelelo Diane N’guilé Benoî t Elowa Timothé e Mobima Francky Kouandogui Bangué Eveline Mofini Yangba Kalebanga Armelo Thibaut Bessanguem Bernard Boniface Koffi 《肠胃病学期刊(英文)》 2020年第4期97-105,共9页
Objective: To describe the epidemiological, clinical, biological and morphological aspects of primary liver cancer (PLC). Patients and Methods: We conducted a 38-month cross-sectional study in the Department of hepato... Objective: To describe the epidemiological, clinical, biological and morphological aspects of primary liver cancer (PLC). Patients and Methods: We conducted a 38-month cross-sectional study in the Department of hepatogas-troenterology and Internal Medicine “Amitié Sino-Centrafraine” University Hospital Center in Bangui. Included in the study were all patients with a diagnosis of PLC. The PLC’s diagnostic arguments were the large tumor liver associated or not with the elevation of alpha-fetoprotein, the heteronodular liver hypervascularized on abdominal ultrasound. Data analysis was done using Epi Info 3.5.1 software. Results: We collected 115 cases of CPF among 2410 hospitalized patients (4.7%). There were 86 men and 29 women (sex ratio: 2.9). The average age was 50 years old. The main risk factors were alcohol consumption (72.2%) and chronic hepatitis B infection (67.4%). Frequent clinical signs were pain in the right hypochondrium and/or epigastric (93.86%), large tumor liver under examination (91.3%), weight loss (74.78%). The serum alpha-fetoprotein concentration was ≥ 400 ng/ml in 73% of the cases. The abdominal ultrasound found a heteronodular liver in all patients. The nodules were multiple hyperechoic in 66.1% of the cases. According to the Child-Pugh classification, the patients were classified as B (49.5%) and C (33.9%). The Okuda Classification ranked patients at stage 1 in 16.5% cases, stage 2 in 52.1% cases and stage 3 in 31.3% cases. According to the BCLC classification, 5.2% of patients were in stage A, 12.2% in stage B, 52.2 in stage C and 30.4% in stage D. Death was recorded during hospitalization in 89 cases (77.4%). Conclusion: CPF is a frequent and serious pathology in Bangui. Its diagnosis is often late, preventing curative treatment. The main causes are alcohol consumption and the hepatitis B virus. The population should be educated to reduce the incidence of this disease. 展开更多
关键词 Primary Liver Cancer EPIDEMIOLOGY CLINICAL MORPHOLOGY Bangui
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Forage Production and Selection for Vigor in Meadow and Hybrid Bromegrass in the Northern Great Plains 认领
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作者 R. Martine Similien Arvid Boe Bruce Coulman 《美国植物学期刊(英文)》 2020年第1期91-110,共20页
Meadow bromegrass (Bromus riparius Rehmann) is an important forage crop in Canada and the Intermountain West, but it has not been extensively evaluated in the northern Great Plains (NGP). Our objectives were to 1) eva... Meadow bromegrass (Bromus riparius Rehmann) is an important forage crop in Canada and the Intermountain West, but it has not been extensively evaluated in the northern Great Plains (NGP). Our objectives were to 1) evaluate meadow, smooth, and hybrid bromegrasses for forage production under intensive management in eastern South Dakota, and 2) evaluate the effect of selection for vigor in multiple environments on forage production of meadow bromegrass. Thirteen populations (7 meadow bromegrass, 5 hybrid bromegrass, and 1 smooth bromegrass) were evaluated for 4 yrs (2005-2007, 2009) at Brookings, SD. Biomass at anthesis was greater for smooth (6.75 Mg ha-1) than for meadow or hybrid brome (5.4 Mg ha-1) in 2005, but production at anthesis during 2006 and 2007 was similar for meadow and smooth bromegrass. Regrowth harvested during July and October 2005 and November 2006 was greater for meadow than smooth or hybrid bromegrass. Forage production at anthesis in 2009, after rest (i.e., no cutting) and fertilization in 2008, was 4.2 Mg ha-1 for meadow bromegrass compared with 3.3 Mg ha-1 and 2.6 Mg ha-1 for hybrid and smooth bromegrass, respectively. Smooth and hybrid bromegrasses had more leaves·tiller-1 than meadow bromegrass. After 6 yrs, meadow bromegrass had higher tiller density and greater potential for tolerating multiple harvests during a growing season than did smooth or hybrid bromegrass. Selection for vigor in multiple environments in North America resulted in experimental populations of meadow bromegrass with superior forage yield compared with ‘Fleet’ on marginal crop land in the northern Great Plains. 展开更多
关键词 BROMUS riparius Smooth BROMEGRASS BROMUS inermis Morphology Phytomer Biomass Partitioning Leaf Ratio TILLER Density Marginal CROPLAND
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Sedimentary Inputs and Morphology Characterization of the Bottom Agropastoral Lake of Nafoun (North Ivory Coast) 认领
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作者 Anzoumanan Kamagate Yao Blaise Koffi +4 位作者 Kouassi Ernest Ahoussi Michel Amani Kouassi Hermann Essan Ehui Kouassi Serge Aristide Yao Seydou Diallo 《水资源与保护(英文)》 2020年第5期389-400,共12页
A bathymetric and sedimentological analysis carried out respectively in July 2017 and April 2018 made it possible to characterize the sediments and the morphology of Lake Nafoun. The sediments of the lake consist of v... A bathymetric and sedimentological analysis carried out respectively in July 2017 and April 2018 made it possible to characterize the sediments and the morphology of Lake Nafoun. The sediments of the lake consist of vases, fine to very coarse sands with average particle sizes ranging from 475.67 and 2111 μm. There is a predominance of very coarse elements (43.50%). The standard deviation of the lake sand is between 1.21 and 1.86 and is poorly classified. The skewness fluctuates between ?0.06 and 0.41. The sediments were deposited at the bottom of the lake due to a progressive decline in the flow of water that carried them. Moreover, this study made it possible to realize the first bathymetric chart of Lake Nafoun, 42 years after its impoundment in 1975. 展开更多
关键词 SEDIMENTS Morphology Nafoun LAKE BATHYMETRY
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Development of heartwood,sapwood,bark,pith and specific gravity of teak(Tectona grandis)in fast-growing plantations in Costa Rica 认领
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作者 Alexander Berrocal Johana Gaitan-Alvarez +2 位作者 Roger Moya David Fernandez-Solis Edgar Ortiz-Malavassi 《林业研究:英文版》 SCIE CAS CSCD 2020年第2期667-676,共10页
To elucidate the development of heartwood,bark,sapwood,pith and specific gravity of wood in fastgrowing teak(Tectona grandis)plantations in Costa Rica,we sampled three trees in each of 55 plantations and modelled each... To elucidate the development of heartwood,bark,sapwood,pith and specific gravity of wood in fastgrowing teak(Tectona grandis)plantations in Costa Rica,we sampled three trees in each of 55 plantations and modelled each variable with age,site and different tree heights.Age and stand density of plantations were significant correlated with stem diameter at breast height and total height of the tree.Formation of heartwood was initiated at the age of 4-year-old and increased in direct proportion with age.The age of plantation had a significant relationship with stem diameter at breast height,heartwood percentage,sapwood thickness,sapwood percentage,percentage of bark,pith diameter and percentage,and specify gravity.The model for these tree parameters was model with these parameters as dependent variable and in relation to age as independent variable. 展开更多
关键词 TEAK Growth TREE MORPHOLOGY parameters MORPHOLOGY TREE DEVELOPMENT
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Preparation and Characterization of Polymer Nanocomposites 认领
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作者 Pratima Parashar Pandey 《软纳米科学报(英文)》 2020年第1期1-15,共15页
The polymer nanocomposites have been the exponentially growing field of research for developing the materials in last few decades. The remarkable improvement in the polymer nanocomposite is found when a small amount o... The polymer nanocomposites have been the exponentially growing field of research for developing the materials in last few decades. The remarkable improvement in the polymer nanocomposite is found when a small amount of nanosized particles are added to a polymer matrix. The addition of inorganic solid nanoparticles (typically in the form of fibres, flakes, spheres or fine particles) into polymer matrix increases their physical, structural and mechanical properties. Since the polymer-nano composites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. This leads to focus on preparation & characterization of polymer nanocomposite. This article is intended to review the status of worldwide research in this aspect. The successful application of nano particles depends upon both the correct preparation techniques followed by testing through characterization. Surface modification can improve the inherent characteristics of the nano particles and serve to prepare nano composites inexistent in nature. Therefore, some tools as their various properties like electrical, optical and morphological can be used to optimize the preparation of polymer nano composites. This chapter will make an overview about different routes to prepare polymer-based nano composites by extrusion, synthesis of nano particles by sol-gel reactions, sputtering and mainly by physical evaporation deposition method. 展开更多
关键词 SILVER NANO-PARTICLE Polymer Composite Electrical PROPERTIES Optical PROPERTIES DSC FTIR SEM MORPHOLOGY
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阳极氧化对TC4钛合金力学与耐磨性能的影响 认领
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作者 李小妮 罗志峰 《电镀与涂饰》 CAS CSCD 北大核心 2020年第7期416-420,共5页
对比分析了脉冲阳极氧化和直流阳极氧化工艺对TC4钛合金表面形貌、拉伸性能、疲劳强度和耐磨性的影响。结果表明,脉冲阳极氧化和直流阳极氧化膜的粗糙度相较于TC4钛合金更大,而表面硬度从高至低为:脉冲阳极氧化膜>TC4钛合金>直流... 对比分析了脉冲阳极氧化和直流阳极氧化工艺对TC4钛合金表面形貌、拉伸性能、疲劳强度和耐磨性的影响。结果表明,脉冲阳极氧化和直流阳极氧化膜的粗糙度相较于TC4钛合金更大,而表面硬度从高至低为:脉冲阳极氧化膜>TC4钛合金>直流阳极氧化膜。虽然阳极氧化后试样的力学性能都相较于处理前有不同程度的减小,但是耐磨性有较大的提升。脉冲阳极氧化试样的疲劳强度接近TC4钛合金基材,且明显高于同样膜厚的直流阳极氧化试样,它的强度、断后伸长率和耐磨性也更优。 展开更多
关键词 体育器械 钛合金 阳极氧化 脉冲 直流 形貌 耐磨性
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应用形态学的自适应门限干扰检测算法 认领
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作者 赵肖迪 李芳 +2 位作者 熊俊 王玲 魏急波 《信号处理》 CSCD 北大核心 2020年第4期593-601,共9页
该文针对通信信号中背景噪声复杂的问题,应用数字形态学的信号预处理方法,能较好地滤除背景噪声;又由于单一门限值难以实现对不同宽度干扰的检测,提出一种应用形态学自适应门限的干扰检测算法。此算法首先对信号谱线进行功率谱估计,然... 该文针对通信信号中背景噪声复杂的问题,应用数字形态学的信号预处理方法,能较好地滤除背景噪声;又由于单一门限值难以实现对不同宽度干扰的检测,提出一种应用形态学自适应门限的干扰检测算法。此算法首先对信号谱线进行功率谱估计,然后利用形态学的方法进行预处理,再根据信号功率谱的分布情况,选取不同的门限值,实现门限的自适应,为检测不同占有用信号带宽大小的窄带干扰提供了有效的方法。该文提出的方法不会受噪底变化的影响,计算量小,复杂度较低,适用于星上卫星通信的实时频谱监测。经过Matlab仿真实验得出,当采用结构元素长度为25的扁平型结构元素时,通过形态学中的膨胀预处理方法以及自适应门限可以得到检测效果比传统的连续均值去除算法(CME)算法有6 dB以上的提升。 展开更多
关键词 卫星通信 形态学 膨胀运算 自适应门限
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Higher leaf area through leaf width and lower leaf angle were the primary morphological traits for yield advantage of japonica/indica hybrids 认领
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作者 WEI Huan-he YANG Yu-lin +8 位作者 SHAO Xing-yu SHI Tian-yi MENG Tian-yao LU Yu TAO Yuan LI Xin-yue DING En-hao CHEN Ying-long DAI Qi-gen 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第2期483-494,共12页
The yield potential of japonica/indica hybrids(JIH)has been achieved over 13.5 t ha–1 in large-scale rice fields,and some physiological traits for yield advantage of JIH over japonica inbred rice(JI)and indica hybrid... The yield potential of japonica/indica hybrids(JIH)has been achieved over 13.5 t ha–1 in large-scale rice fields,and some physiological traits for yield advantage of JIH over japonica inbred rice(JI)and indica hybrid rice(IH)were also identified.To date,little attention has been paid to morphological traits for yield advantage of JIH over JI and IH.For this reason,three JIH,three JI,and three IH were field-grown at East China(Ningbo,Zhejiang Province)in 2015 and 2016.Compared with JI and IH,JIH had 14.3 and 20.8%higher grain yield,respectively,attributed to its more spikelets per panicle and relatively high percentage of filled grains.The advantage in spikelets per panicle of JIH over JI and IH was shown in number of grains on the upper,middle,and lower branches.Compared with JI and IH,JIH had higher leaf area through leaf width and lower leaf angle of upper three leaves,higher leaf area index and leaf area per tiller at heading and maturity stages,higher stem weight per tiller and K and Si concentrations of stem at maturity,higher dry matter weight in leaf,stem,and panicle at heading and maturity stages,and higher biomass accumulation after heading and lower biomass translocation from stem during ripening.Leaf width of upper three leaves were correlated positively,while leaf angle of upper three leaves were correlated negatively with biomass accumulation after heading,stem weight per tiller,and per unit length.Our results indicated that the grain yield advantage of JIH was ascribed mainly to the more spikelets per panicle and relatively high percentage of filled grains.Higher leaf area through leaf width and more erect leaves were associated with improved biomass accumulation and stem weighing during ripening,and were the primary morphological traits underlying higher grain yield of JIH. 展开更多
关键词 japonica/indica HYBRIDS plant-type TRAITS leaf morphology
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Low-temperature plasma enhanced atomic layer deposition of large area HfS2 nanocrystal thin films 认领
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作者 常爱玲 毛亦琛 +5 位作者 黄志伟 洪海洋 徐剑芳 黄巍 陈松岩 李成 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第3期427-432,共6页
Hafnium disulfide(HfS2) is a promising two-dimensional material for scaling electronic devices due to its higher carrier mobility, in which the combination of two-dimensional materials with traditional semiconductors ... Hafnium disulfide(HfS2) is a promising two-dimensional material for scaling electronic devices due to its higher carrier mobility, in which the combination of two-dimensional materials with traditional semiconductors in the framework of CMOS-compatible technology is necessary. We reported on the deposition of HfS2 nanocrystals by remote plasma enhanced atomic layer deposition at low temperature using Hf(N(CH3)(C2H5))4 and H2S as the reaction precursors. Selflimiting reaction behavior was observed at the deposition temperatures ranging from 150℃ to 350℃, and the film thickness increased linearly with the growth cycles. The uniform HfS2 nanocrystal thin films were obtained with the size of nanocrystal grain up to 27 nm. It was demonstrated that higher deposition temperature could enlarge the grain size and improve the HfS2 crystallinity, while causing crystallization of the mixed HfO2 above 450℃. These results suggested that atomic layer deposition is a low-temperature route to synthesize high quality HfS2 nanocrystals for electronic device or electrochemical applications. 展开更多
关键词 HfS2 ATOMIC LAYER DEPOSITION surface MORPHOLOGY
钝叶柃花器官性别分化的形态学研究 认领
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作者 顾梨 何平 +4 位作者 邓洪平 倪东萍 王茜 程莅登 巴罗菊 《林业科学》 EI CAS CSCD 北大核心 2020年第2期174-183,共10页
【目的】柃木属植物为热带和亚热带常绿阔叶林灌木层优势种,传统认为是严格的雌雄异株,但在重庆缙云山钝叶柃却存在性别变异现象,即除了典型的雌株、雄株还有两性变异株。通过对不同分化时期的花芽进行形态和结构观察,比较两性变异花芽... 【目的】柃木属植物为热带和亚热带常绿阔叶林灌木层优势种,传统认为是严格的雌雄异株,但在重庆缙云山钝叶柃却存在性别变异现象,即除了典型的雌株、雄株还有两性变异株。通过对不同分化时期的花芽进行形态和结构观察,比较两性变异花芽与典型的雌花芽、雄花芽分化过程的异同,旨在掌握钝叶柃不同性别花芽分化的整体进程及各分化时期的形态特征,明确花芽性别分化的关键时期,进而为探讨性别分化的相关机理提供重要的形态学证据。【方法】以钝叶柃典型的雌株、雄株、两性变异株的花芽为试验材料,采用常规石蜡切片法对花芽分化过程中的外部形态变化和组织结构进行观察分析。【结果】1)钝叶柃1~4个花芽着生于当年生新枝及2年生枝叶腋处;2)花芽分化始于8月上旬,12月中下旬基本完成,历时120天左右,之后花芽处于休眠状态,次年2—3月进入始花期,两性变异花花芽分化时间晚于雄花芽、雌花芽;3)花芽分化大致可以划分为5个时期,即苞片分化期、萼片分化期、花瓣分化期、雌雄蕊分化期、雌雄蕊成熟期;4)在花芽发育过程中,两性变异花芽和雄花芽的雌雄蕊原基同时出现,雄花中雄蕊原基正常发育而雌蕊原基停止发育,两性变异花中雌雄蕊原基皆正常发育;雌花中只见雌蕊原基,未见雄蕊原基。5)在雌雄蕊分化期,两性变异花中,雌蕊原基发育速度略快于雄蕊原基,雌蕊发育与雌花一致,中央心皮原基基部愈合膨大,中部凹陷形成子房室,顶端愈合向上延伸形成花柱;雄蕊发育与雄花一致,雄蕊原基上端膨大形成花药,下端形成短的花丝。在雌雄蕊成熟期各花器官继续生长,发育日趋成熟。6)3种不同性别花芽长宽比在分化的整个过程中均呈先上升后下降的趋势,雄花芽在萼片分化期长宽比值达到峰值,而雌花芽、两性变异花芽均在雌雄蕊分化期达到峰� 展开更多
关键词 钝叶柃 花芽分化 性别变异 形态
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银纳米颗粒的化学还原法制备简介及其应用 认领
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作者 胡青 吴春芳 《功能材料》 EI CAS CSCD 北大核心 2020年第4期4046-4053,共8页
银纳米颗粒的光学性能,如局域表面等离子体共振(Localized Surface Plasmon Resonance,LSPR)特性可通过其形貌、尺寸、外部介电环境的调控而实现变化。不同形貌的银纳米颗粒具有强弱不同的局域表面等离子体共振效应,从而表现出独特的光... 银纳米颗粒的光学性能,如局域表面等离子体共振(Localized Surface Plasmon Resonance,LSPR)特性可通过其形貌、尺寸、外部介电环境的调控而实现变化。不同形貌的银纳米颗粒具有强弱不同的局域表面等离子体共振效应,从而表现出独特的光学性质。综述了利用化学还原法制备不同形貌的银纳米颗粒,主要包括柠檬酸钠还原法、多元醇法以及种子介导生长法,分析了这3种合成方法的机理和特点,将近年来不同形貌银纳米颗粒的研究进展进行了综述。最后介绍了不同形貌银纳米颗粒在表面增强拉曼散射(Surface-Enhanced Roman scattering,SERS)基底、催化、抗菌领域上的应用研究,并总结和展望了银纳米颗粒在合成和相关应用领域的发展前景。 展开更多
关键词 银纳米颗粒 局域表面等离子体共振 形貌 化学还原 表面增强拉曼散射
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形貌对LiNi0.5Mn1.5O4正极材料性能影响研究 认领
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作者 杨尘 许鹏 汪涛 《广东化工》 CAS 2020年第7期67-68,84,共3页
采用高温固相法通过不同混料介质与相应的干燥方法合成了形貌为球状和分散状的LiNi0.5Mn1.5O4。利用FE-SEM、XRD及充放电性能测试等手段对比了材料的形貌、物相和电化学行为。结果表明:分散状的材料由于一次粒子更小具有优良的电化学性... 采用高温固相法通过不同混料介质与相应的干燥方法合成了形貌为球状和分散状的LiNi0.5Mn1.5O4。利用FE-SEM、XRD及充放电性能测试等手段对比了材料的形貌、物相和电化学行为。结果表明:分散状的材料由于一次粒子更小具有优良的电化学性能,0.2 C倍率下材料的首次放电比容量为135 mAh/g,12 C倍率下放电比容量为115 mAh/g。1C倍率充放电循环50次容量保持率为99.5%。 展开更多
关键词 LINI0.5MN1.5O4 固相法 形貌 电化学性
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南粤地区女性外阴形态结构影响因素的研究 认领
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作者 黄恩杰 苏秀梅 +1 位作者 王燕珠 罗新 《中国美容整形外科杂志》 CAS 2020年第3期133-136,共4页
目的通过观察及测量女性外阴形态结构,探究女性外阴形态结构与一般人口学特征的关系。方法选择自2016年9月至2017年6月收治的309例绝经前女性患者进行外阴测量,每例患者观察4个指标,共测量15个参数,比较观察指标及测量数值与年龄、身高... 目的通过观察及测量女性外阴形态结构,探究女性外阴形态结构与一般人口学特征的关系。方法选择自2016年9月至2017年6月收治的309例绝经前女性患者进行外阴测量,每例患者观察4个指标,共测量15个参数,比较观察指标及测量数值与年龄、身高、体质量、体质量指数、生育史的关系。结果本组患者中,小阴唇形状大部分为卵圆弧形(197例,占63.8%),阴蒂头多为包裹在阴蒂包皮内(193例,占62.5%),轻推包皮即外露;大阴唇形态多为正常隆起(230例,占74.4%)。女性外阴测量主要参数值:左小阴唇基底长度(44.04±9.56) mm,右小阴唇基底长度(43.46±10.09) mm;左小阴唇宽度(15.31±6.15) mm,右小阴唇宽度(14.75±6.28) mm;左小阴唇厚度(3.95±1.32) mm,右小阴唇厚度(3.99±1.27) mm。大阴唇长度(82.29±8.52) mm;左大阴唇宽度(22.45±3.14) mm,右大阴唇宽度(22.47±3.18) mm;阴蒂头长度(4.52±1.91) mm,阴蒂头宽度(3.12±1.34) mm,阴蒂包皮长度(24.13±5.20) mm。左、右两侧小阴唇宽度均与年龄呈正相关(B=0.148,0.191;P<0.01),与经阴道分娩次数呈负相关(B=-2.423,-1.220;P<0.01),大阴唇长度及左、右大阴唇宽度则均与体质量呈正相关(B=0.291,0.121,0.094;P<0.01)。结论女性外阴形态及测量值个体差异较大,其中以小阴唇测量值变异最大。部分测量参数显示与年龄、体质量、产次及经阴道分娩次数相关。 展开更多
关键词 女性外阴 生殖器整形手术 形态学 测量学
侗族村寨空间形态继承性发展研究--以黎平县滚正村为例 认领
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作者 郑建邦 田银生 《城市建筑》 2020年第9期67-72,共6页
针对新时期背景下西南地区少数民族村寨保护与发展问题,提出少数民族村寨继承性发展概念,以侗族村寨滚正村为例,探讨适应少数民族村寨保护与发展的规划技术方法。通过典型形态要素识别、空间单元分类导控以及传统民居建筑类型演化的方式... 针对新时期背景下西南地区少数民族村寨保护与发展问题,提出少数民族村寨继承性发展概念,以侗族村寨滚正村为例,探讨适应少数民族村寨保护与发展的规划技术方法。通过典型形态要素识别、空间单元分类导控以及传统民居建筑类型演化的方式,达到少数民族村寨文化传承与当代发展共赢的目的。 展开更多
关键词 侗族 少数民族村寨 保护与发展 形态学
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以3D图形观察不同中医证型股骨头坏死髋关节形态差异:评价非手术保髋的可行性 认领
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作者 林天烨 杨鹏 +8 位作者 魏秋实 徐景利 邹启昭 熊冰朗 赖启忠 赵赫然 陈镇秋 何伟 张庆文 《中国组织工程研究》 CAS 北大核心 2020年第24期3773-3779,共7页
背景:有研究发现中医证型分布与股骨头坏死的形态差异表现之间存在一定的联系。目的:通过3D图形观察不同中医证型股骨头坏死髋关节的形态差异,同时评价规范化综合非手术保髋治疗股骨头坏死的疗效。方法:选择2016年12月至2017年2月广州... 背景:有研究发现中医证型分布与股骨头坏死的形态差异表现之间存在一定的联系。目的:通过3D图形观察不同中医证型股骨头坏死髋关节的形态差异,同时评价规范化综合非手术保髋治疗股骨头坏死的疗效。方法:选择2016年12月至2017年2月广州中医药大学第一附属医院行非手术保髋治疗的股骨头坏死患者73例(108髋),按中医证型分为肾虚血瘀组47髋、痰瘀蕴结组30髋、气滞血瘀组31髋,拍摄双髋正蛙位X射线片与CT螺旋扫描,测量患髋中心边缘角、Sharp角、髋臼上下径、髋臼前后径、髋臼深度、髋臼外展角、髋臼前倾角。纳入2016年12月至2017年2月广州中医药大学第一附属医院接受中医药、物理治疗、功能锻炼等规范化综合保髋治疗股骨头坏死患者88例(131髋),治疗前及治疗后2年采用目测类比评分与Harris评分患髋临床功能,并通过X射线片评估治疗区坏死情况。试验已通过广州中医药大学第一附属医院伦理委员会批准,批准号:NO.Y[2019]118。结果与结论:①X射线显示,不同中医证型组间Sharp角、中心边缘角存在明显差异(P<0.01),其中肾虚血瘀型组Sharp角最大、中心边缘角最小,气滞血瘀型组Sharp角最小、中心边缘角最大;②CT螺旋扫描显示,不同中医证型组间外展角存在差异(P<0.001),其中肾虚血瘀型组最大;肾虚血瘀型组髋臼深度小于气滞血瘀型组(P<0.05);3组间髋臼上下径、髋臼前后径、髋臼前倾角无明显差异;③综合保髋治疗2年后,88例患者的疼痛与髋关节功能得到明显改善,影像学评估显示改善89髋、不变21髋,改善率为67.9%;④结果表明,不同证型之间的髋关节形态存在差异,肾虚血瘀型髋臼发育情况较气滞血瘀型、痰瘀蕴结型差,规范化综合非手术保髋治疗早、中期股骨头坏死在短期内能够明显改善患者症状。 展开更多
关键词 股骨头坏死 可视化 形态 证型 保守治疗 中医 差异 可行性
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广西涠洲岛底栖甲藻前沟藻属(Amphidinium)种类的形态学和系统发育学研究 认领
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作者 江丽春 李群 吕颂辉 《热带海洋学报》 CAS CSCD 北大核心 2020年第3期106-115,共10页
本文对采集自我国广西涠洲岛海域潮下带大型海藻及死珊瑚上的附着底栖甲藻样品进行了分析。利用毛细管单细胞分离方法成功分离并培养了多株前沟藻属种类,运用光学显微镜、扫描电镜和分子生物学等技术,对所获得的前沟藻株系进行形态学和... 本文对采集自我国广西涠洲岛海域潮下带大型海藻及死珊瑚上的附着底栖甲藻样品进行了分析。利用毛细管单细胞分离方法成功分离并培养了多株前沟藻属种类,运用光学显微镜、扫描电镜和分子生物学等技术,对所获得的前沟藻株系进行形态学和系统发育分析,鉴定出前沟藻属3个种,分别为具盖前沟藻(Amphidinium operculatum)、玛氏前沟藻(Amphidinium massertii)和强壮前沟藻(Amphidinium caeterae),其中具盖前沟藻和玛氏前沟藻为我国新纪录种。分析比较了不同种类间形态和系统发育的差异,发现3种前沟藻的形态特征大体与相应模式种报道的一致。本研究丰富了我国前沟藻种类多样性和系统发育进化信息,同时将两个新记录种具盖前沟藻和玛氏前沟藻的已知分布范围拓展到了我国南部沿海水域。 展开更多
关键词 涠洲岛 前沟藻 形态学 系统发育
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CuNi纳米晶的可控合成及Pt/CuNi催化剂催化肉桂醛加氢性能 认领
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作者 张欢 阮露娜 +4 位作者 裴安 艾文斌 吴锋顺 熊晚枫 朱丽华 《化工进展》 EI CAS CSCD 北大核心 2020年第5期1774-1783,共10页
采用水热法制备了CuNi二元金属纳米晶。以水合肼为还原剂,探究水热合成温度、表面活性剂[乙二胺(EDA)、聚乙烯吡咯烷酮(PVP)、十六烷基三甲基溴化铵(CTAB)]对CuNi纳米晶形貌的影响。随水热合成温度的升高(60℃、90℃、120℃、150℃),Cu2... 采用水热法制备了CuNi二元金属纳米晶。以水合肼为还原剂,探究水热合成温度、表面活性剂[乙二胺(EDA)、聚乙烯吡咯烷酮(PVP)、十六烷基三甲基溴化铵(CTAB)]对CuNi纳米晶形貌的影响。随水热合成温度的升高(60℃、90℃、120℃、150℃),Cu2+、Ni2+的还原速率加快,有利于形成Cu@Ni核壳结构。以EDA为表面活性剂时,制备的CuNi二元金属纳米晶在120℃和150℃时分别呈现花状和海胆状。此外,以CuNi纳米晶为催化剂载体,采用化学置换法负载贵金属Pt合成了Pt/CuNi三元金属催化剂。X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、扫描电镜X射线能谱(SEM-EDS)、X射线光电子能谱(XPS)、高角度环形暗场扫描透射(HAADF-STEM)和元素面扫(STEM-EDS)表征结果表明,Pt/CuNi催化剂纳米结构为小岛状的Pt纳米团簇负载于CuNi纳米晶。其中,Pt/CuNi-120-EDA(120为水热合成温度,EDA为制备CuNi纳米晶时添加的表面活性剂)催化剂表面具有较丰富的缺陷位和活性位点,使其在肉桂醛加氢反应中表现出最佳的催化性能(80℃下对苯丙醇的产率达100%)。 展开更多
关键词 纳米结构 水热 加氢 催化剂 形貌
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长江中游湖泊鳜与大眼鳜的渐渗杂交 认领
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作者 朱书琴 曹晓颖 +2 位作者 赵金良 唐首杰 吴红岩 《上海海洋大学学报》 CAS CSCD 北大核心 2020年第1期1-8,共8页
在长江中游鄱阳湖和洞庭湖鳜采样中,采集了兼具鳜(Siniperca chuatsi)和大眼鳜(S.kneri)部分形态特征的中间类型(主要特征:口裂后缘伸达眼睛后缘之下,眼睛大小、头后背前部隆起介于鳜与大眼鳜之间)48尾。为了明确中间类型的分类学关系,... 在长江中游鄱阳湖和洞庭湖鳜采样中,采集了兼具鳜(Siniperca chuatsi)和大眼鳜(S.kneri)部分形态特征的中间类型(主要特征:口裂后缘伸达眼睛后缘之下,眼睛大小、头后背前部隆起介于鳜与大眼鳜之间)48尾。为了明确中间类型的分类学关系,采用量化传统形态分类指标、筛选种间特异微卫星标记,对中间类型个体进行鉴定分析。结果:(1)量化分析表明,鳜和大眼鳜在头长/眼径、(吻长+眼径)/口裂长上存在显著差异,鳜头长/眼径为5.286~7.157、(吻长+眼径)/口裂长为0.811~0.999,大眼鳜分别为3.306~5.106和1.040~1.166。48尾中间类型中,5尾判定为鳜,其他43尾个体仍不能鉴定。(2)从28对微卫星标记中筛选出5个鳜和大眼鳜的种间鉴别位点(T103、T063、T089、T135、W19517),利用这5个位点对中间类型的个体进行遗传分析和鉴定,中间类型中有16尾为种间杂交后代,其中9尾为杂交F1与大眼鳜的回交个体。长江中游湖泊中鳜和大眼鳜存在种间渐渗杂交,今后需加强长江鳜鱼野生资源遗传监测和管理。 展开更多
关键词 大眼鳜 中间类型 形态学 微卫星 渐渗杂交
Morphological and ecological divergence in two populations of European glass lizard,Pseudopus apodus(Squamata:Anguidae) 认领
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作者 Olga Jovanovic Glavas Paula Pocanic +3 位作者 Vanja Lovric Lorena Derezanin Zoran Tadic Duje Lisicic 《动物学研究》 SCIE CAS CSCD 2020年第2期172-181,共10页
The European glass lizard,Pseudopus apodus(Pallas,1775),is a large,legless lizard with wide distribution across south-eastern Europe and eastern and central Asia.To date,morphological diversification among populations... The European glass lizard,Pseudopus apodus(Pallas,1775),is a large,legless lizard with wide distribution across south-eastern Europe and eastern and central Asia.To date,morphological diversification among populations on a geographically small scale has not yet been reported in this lizard.Thus,we investigated the morphological variations and corresponding differences in habitat utilization between two populations of P.apodus inhabiting the same biogeographical zone within a relatively close geographic area.We hypothesized that minor differences in habitat could induce a significant level of morphological differentiation,thus indicating morphological plasticity in this species on a small geographical scale.We sampled 164 individuals(92 from the Croatian mainland and 72 from the island of Cres).Results showed that P.apodus indeed exhibited morphological differences between populations in the same biogeographical zone within a relatively close geographic area,with the Cres Island individuals being generally larger than the individuals from the mainland.Some ecological characteristics were similar in both populations(e.g.,soil temperature,distance to hiding place),whereas others were distinct(e.g.,air temperature and humidity).In addition,vegetation cover differed between the two sites,with more vegetation present on the mainland than on the island.Furthermore,the Cres Island population showed clear sexual dimorphism,which was absent in the mainland population. 展开更多
关键词 Mediterranean Morphology SAURIA Sexual DIMORPHISM
新疆翻飞鸽形态构造研究 认领
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作者 帕提古丽·亚森 巴雅尔塔 《新疆师范大学学报:自然科学版》 2020年第1期64-76,共13页
翻飞鸽起源于原鸽(Columba livia),它们具有飞行时空中翻滚的遗传性。选择伊犁州伊宁市、阿克苏地区新和县新和镇和田麦里村和喀什地区疏勒县塔孜洪乡尤喀克霍伊拉村作为新疆翻飞鸽样本采样区,对翻飞鸽样本头部、躯体和飞羽合计42项形... 翻飞鸽起源于原鸽(Columba livia),它们具有飞行时空中翻滚的遗传性。选择伊犁州伊宁市、阿克苏地区新和县新和镇和田麦里村和喀什地区疏勒县塔孜洪乡尤喀克霍伊拉村作为新疆翻飞鸽样本采样区,对翻飞鸽样本头部、躯体和飞羽合计42项形态数据进行测量。结果显示,头部形态构造中嘴峰长度、嘴裂长度、鼻宽度、鼻长度、鼻深度、头长度和眼球宽度在采样区间变异不显著,眼球高度、头宽度和头深度在采样区间变异显著。躯体形态构造中颈项宽度、下颈宽度、躯体长度、上背宽度和腰宽度在采样区间变异不显著,胸宽度在采样区间变异显著。初级飞羽长度随初级飞羽序呈现显著递减,次级飞羽长度随次级飞羽序呈现左右两侧次级飞羽短和中央次级飞羽长的特征,初级飞羽长度、次级飞羽长度和尾羽长度在采样区间变异显著。左侧第1枚尾羽长度与右侧第1枚尾羽长度间差异不显著,中央尾羽长度分别显著长于左右两侧第1枚尾羽长度。结论:在新疆不同地区翻飞鸽样本中头部形态构造和躯体形态构造间变异不显著,飞羽形态学构造间变异显著。 展开更多
关键词 翻飞鸽 形态 构造 变异 显著性 新疆
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