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Zooneuston and zooplankton abundance and diversity in relation to spatial and nycthemeral variations in the Gulf of Aqaba and northern Red Sea
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作者 Gopikrishna Mantha Abdulmohsin AAl-Sofyani +1 位作者 Al-Aidaroos Ali M Michael P Crosby 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第12期59-72,共14页
Zooplankton and zooneuston observations were made at seven stations(four from the Gulf of Aqaba and three from the northern Red Sea), during September and October 2016. The main objective of this study was to assess t... Zooplankton and zooneuston observations were made at seven stations(four from the Gulf of Aqaba and three from the northern Red Sea), during September and October 2016. The main objective of this study was to assess the variability of nycthemeral fauna in relation to the sampling methods using two different types of nets namely,WP2 net and Neuston net along the two study sites, i.e., the Gulf of Aqaba and the northern Red Sea. Zooplankton was sampled vertically using a standard WP2 net from a depth of 200 m to the surface, whereas zooneuston was made using a standard Neuston net from a depth of 0–10 cm of the water surface. Total zooplankton density was maximum during night time((617.83 ± 201.84) ind./m^3) at the Gulf of Aqaba and total zooneuston was maximum during night at the northern Red Sea((60.94±29.48) ind./m^3), respectively. The most abundant taxa were Copepoda, Gastropoda, Bivalva, Chaetognatha, Tunicata and Ostracoda. The abundance was almost 50% higher at night time at both the Gulf of Aqaba and the northern Red Sea. Overall, 30 taxa covering 10 phyla and 27 taxa covering 8 phyla were recorded in the Gulf of Aqaba and the northern Red Sea. 展开更多
关键词 ZOOPLANKTON zooneuston nycthemeral variation CYCLOPOIDA Gulf of Aqaba northern red Sea
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Phytolith Records in Vermicular Red Earth:Implications for Bioclimatic Variationsduring Pleistocene
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作者 Gu Yansheng Zhuo Ying Zhang Zejun Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2001年第1期27-30,共4页
Phytolith analysis is employed in bioclimatic research into vermicular red earth, especially into its form, assemblage and zonation. The phytolith assemblage is divided into 10 zones. The statistics and main factor an... Phytolith analysis is employed in bioclimatic research into vermicular red earth, especially into its form, assemblage and zonation. The phytolith assemblage is divided into 10 zones. The statistics and main factor analysis of phytolith show that the obtained main factor load curves could suggest a climate change. Combined with phytolith assemblage feature, the bioclimatic variation of vermicular red earth during its formation stage, consisting of 5 arid-cold stages, 4 warm-humid stages and 2 mild stages, is reconstructed in detail. The research results indicate that phytolith records are ideal paleoclimatic signals in vermicular red earth, and that abundant information on environmental evolution can be located. 展开更多
关键词 phytolith records vermicular red earth bioclimatic variation.
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Preliminary Study on Geographical Variation of Cytochrome b gene and ITS2-rDNA among Populations of Rhynchophorus ferrugineus 被引量:1
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作者 R. A. A. M. EI-Mergawy A. M. A1 Ajlan +5 位作者 N. Abdalla V. Vassiliou C. Capdevielle-Dulac D.C.Kontodimas J. F. Silvain M. I. Nasr 《Journal of Agricultural Science and Technology(B)》 2011年第2期189-197,共9页
The Red Palm Weevil (RPW), Rhynchophorus ferrugineus (Olivier), (Coleoptera, Curculionidae, Rhynchophorinae), is an invasive species that is originated from Southeast Asia. It has invaded Middle East, several co... The Red Palm Weevil (RPW), Rhynchophorus ferrugineus (Olivier), (Coleoptera, Curculionidae, Rhynchophorinae), is an invasive species that is originated from Southeast Asia. It has invaded Middle East, several countries of the Mediterranean Basin, Caribbean (Island of Curacao, Netherland Antilles), Lebanon and United States of America (Laguna Beach, Orange County, California) during the last three decades where it attacks palm trees. This study investigated the geographical variation among geographic populations of RPW collected from twelve invaded countries using cytochrome b (Cytb) and ITS2 partial sequences. The comparison among the Cytb sequences resulted in three different haplotypes designated as HB 1 to HB3. The three haplotypes were subdivided into two phylogenetic groups according to their geographic positions: (1) the "Multi-Continent" group containing HB 1 haplotype detected in eight populations belonging to three different Continents such as Africa-Egypt, Asia-Kingdom of Saudi Arabia and Turkey and Europe-Spain, Italy, Greece, Cyprus and France, and (2) the "Asian" group includes four populations from Iran (harboring HB2 haplotype), Pakistan, UAE, and Oman (harboring HB3 haplotype). This mitochondrial pattern of genetic diversity suggests that the tested RPW populations subdivided genetically into different sub-populations under the influence of genetic drift. According to these results we concluded that the twelve studied RPW populations are originating from different source populations in the RPW area of origin. 展开更多
关键词 Cytochrome b ITS2 red Palm Weevil invasive species geographical variation.
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Based on the Spectral Variation of Vegetation Monitoring the Heavy Metal Pollution of Soil
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作者 Li Mi School of Information Engineering,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期86-87,共2页
Heavy metal pollution of soil is one of serious problems of environment.Not easy to break down, heavy metal was enriched and became the pollutants. It would not only destroy the normal function of soil and impede the ... Heavy metal pollution of soil is one of serious problems of environment.Not easy to break down, heavy metal was enriched and became the pollutants. It would not only destroy the normal function of soil and impede the growth of crops,but also through the food chain cause the harm to human health.By the impact of heavy metal pollution of soil,the vegetation is also very easy to be contaminated.When the vegetation has been contaminated,its internal structure, 展开更多
关键词 HEAVY metal pollution CHLOROPHYLL SPECTRAL variation red VALLEY parameters
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美国硬红冬和硬红春小麦籽粒品质比较及与中国强筋小麦标准对标分析
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作者 蒋佳丽 刘丰 +8 位作者 谢凯 周琴 蔡剑 王笑 黄梅 仲迎鑫 戴廷波 曹卫星 姜东 《麦类作物学报》 CAS CSCD 北大核心 2024年第5期594-604,共11页
随着人们消费结构的改变,面包市场发展迅速,但中国优质强筋小麦生产供应不足,质量差异较大,而美国硬麦有良好的加工性能和稳定的品质,制粉和烘焙特性优异。研究美国硬红冬小麦和硬红春小麦籽粒品质年度间变化特点及品质指标间相关性,可... 随着人们消费结构的改变,面包市场发展迅速,但中国优质强筋小麦生产供应不足,质量差异较大,而美国硬麦有良好的加工性能和稳定的品质,制粉和烘焙特性优异。研究美国硬红冬小麦和硬红春小麦籽粒品质年度间变化特点及品质指标间相关性,可为中国强筋小麦籽粒品质研究与发展提供参考。本文汇总了美国小麦协会1999—2021年间发布的硬红冬小麦、硬红春小麦品质相关性状数据,分析了两类小麦品质指标间相互关系,并探讨了美国硬麦品质对中国现有强筋小麦标准的适配度。结果表明,与硬红冬小麦相比,硬红春小麦蛋白含量高,筋力强,形成时间、稳定时间等面团品质更高,烘焙品质更优,且籽粒、面粉品质稳定性高。对标中国强筋小麦标准可以发现,硬红春小麦对标中国强筋小麦标准的达标率高于硬红冬小麦,蛋白含量、湿面筋达标率差距尤为明显。综合考虑中国强筋小麦生产现状,并结合美国硬麦对中国强筋小麦标准达标率,中国强筋小麦标准可将蛋白含量调整为>14.5%,湿面筋含量为>32.0%,稳定时间>10 min,容重、硬度分别大于760 g·L^(-1)和65。硬红春小麦品质指标的相关性分析显示,拉伸面积与面包烘焙吸水率显著负相关,与面包体积显著正相关,可用于预测强筋小麦面包品质;中国标准可设置拉伸面积为105 cm^(2)。 展开更多
关键词 硬红冬小麦 硬红春小麦 品质性状 年度变异 达标度
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基于OVMD-KPCA-RTH-GRU的短期光伏发电功率预测
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作者 王红徐 严新军 +2 位作者 夏庆成 刘佳琪 王雪虎 《水力发电》 CAS 2024年第9期98-103,共6页
针对光伏发电功率的随机性、波动性和非线性问题,提出了一种结合经红尾鵟(RTH)算法优化的变分模态分解(VMD)、核主成分分析(KPCA)和经RTH算法优化的门控循环单元(GRU)神经网络的光伏发电功率预测模型。首先,使用RTH算法对VMD和GRU神经... 针对光伏发电功率的随机性、波动性和非线性问题,提出了一种结合经红尾鵟(RTH)算法优化的变分模态分解(VMD)、核主成分分析(KPCA)和经RTH算法优化的门控循环单元(GRU)神经网络的光伏发电功率预测模型。首先,使用RTH算法对VMD和GRU神经网络的5个超参数进行优化;接着,应用优化后的VMD方法分解原始数据,以减少光伏数据的波动性和随机性;然后,采用KPCA方法降低数据维度,消除冗余;最后,利用经RTH优化的GRU神经网络模型进行时序建模。通过分析新疆某光伏电站的历史发电数据,并与GRNN、LSTM、GRU以及OVMD-GRU、OVMD-KPCA-GRU模型相比较,本模型的拟合优度高达98.96%,显示出更高的预测精度。 展开更多
关键词 变分模态分解 核主成分分析 红尾鵟优化算法 门控循环神经网络 光伏功率预测
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基于术前RDW-SD、RDW-CV评估乳腺癌淋巴转移患者预后
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作者 黄蕾 唐文佳 +6 位作者 周琰 周佳烨 张春燕 杨静 王蓓丽 潘柏申 郭玮 《检验医学》 CAS 2024年第4期376-381,共6页
目的 分析乳腺癌淋巴转移患者术前红细胞体积分布宽度标准差(RDW-SD)和红细胞体积分布宽度变异系数(RDW-CV)与其预后的关系。方法 选取2018年1月—2022年2月复旦大学附属中山医院厦门医院经术后病理确诊乳腺癌并发生淋巴转移的女性患者... 目的 分析乳腺癌淋巴转移患者术前红细胞体积分布宽度标准差(RDW-SD)和红细胞体积分布宽度变异系数(RDW-CV)与其预后的关系。方法 选取2018年1月—2022年2月复旦大学附属中山医院厦门医院经术后病理确诊乳腺癌并发生淋巴转移的女性患者156例。收集患者术前RDW-CV和RDW-SD、临床病理指标,以及预后相关信息。采用Cox回归分析评估患者预后不良的影响因素。采用受试者工作特征(ROC)曲线分析RDW-SD和RDW-CV预测患者预后不良的效能。根据RDW-CV、RDW-SD的最佳临界值,将156例乳腺癌淋巴转移患者分为高表达组和低表达组,采用Kaplan-Meier生存曲线比较高表达组和低表达组无病生存率的差异。结果 不同TNM分期的乳腺癌淋巴转移患者之间RDW-SD、RDW-CV差异有统计学意义(P<0.001)。ROC曲线分析结果显示,RDW-CV诊断病理Ⅳ期[曲线下面积(AUC)=0.838,P<0.001)和患者预后不良(AUC=0.773,P<0.001)的效能均优于RDW-SD(AUC分别为0.780、0.729,P<0.05)。Cox回归分析结果显示,术前RDW-CV是预后不良的独立危险因素[风险比(HR)=1.46,95%可信区间(CI)为1.13~1.89,P=0.004]。Kaplan-Meier生存曲线分析结果显示,RDW-CV高表达组和RDW-SD高表达组无病生存率分别低于RDW-CV低表达组和RDW-SD低表达组(P<0.001)。结论 术前RDW-CV对乳腺癌淋巴结转移患者的预后评估价值优于RDW-SD。高RDW-CV是患者预后不良的独立危险因素。 展开更多
关键词 红细胞体积分布宽度标准差 红细胞体积分布宽度变异系数 乳腺癌 淋巴结转移 预后
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17-18世纪中国赤壁赋瓷图像的欧洲传播与变异
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作者 王文欣 《国际汉学》 CSSCI 2024年第3期94-103,158,共11页
明代中晚期出现一类绘东坡夜游赤壁图像并题写长篇《赤壁赋》文字的日用瓷,这类为本土市场烧制的瓷器进入了外销欧洲及世界各地的商品序列。本文将赤壁赋瓷及其图像置于跨文化交流语境中,结合存世器物、书籍插图、考古报告、收藏机构著... 明代中晚期出现一类绘东坡夜游赤壁图像并题写长篇《赤壁赋》文字的日用瓷,这类为本土市场烧制的瓷器进入了外销欧洲及世界各地的商品序列。本文将赤壁赋瓷及其图像置于跨文化交流语境中,结合存世器物、书籍插图、考古报告、收藏机构著录等,讨论17—18世纪赤壁赋瓷图像传播与变异的路径,尤其关注这些传播与变异发生的历史语境,并揭示文化交流的想象与误读。 展开更多
关键词 赤壁赋瓷 图像传播 图像变异 跨文化交流
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结合深度图和红通道最小强度先验的水下图像复原
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作者 李月梅 侯国家 +2 位作者 王国栋 潘振宽 黄宝香 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2024年第6期904-914,共11页
针对水下图像雾化、模糊等问题,提出结合深度图和红通道最小强度先验的水下图像复原变分方法.基于完整的水下成像模型,首先设计了一种自适应加权融合亮度、梯度及色差等信息的场景深度估计方法,计算3个通道的透射率;然后根据前向散射分... 针对水下图像雾化、模糊等问题,提出结合深度图和红通道最小强度先验的水下图像复原变分方法.基于完整的水下成像模型,首先设计了一种自适应加权融合亮度、梯度及色差等信息的场景深度估计方法,计算3个通道的透射率;然后根据前向散射分量建立变分模型的数据项,对拟复原图像引入红通道最小强度先验作为变分能量方程规则项,借助图像金字塔,采用粗尺度到细尺度逐步优化策略进行模糊核估计;最后利用交替方向乘子法迭代求解,解决变分模型带来的非光滑优化问题.在UIEB数据集上进行了定性和定量实验,通过UCIQE,FADE和CPBD客观评价指标对比,结果表明,所提方法的评价结果比经典方法平均分别提升15%以上,复原后的图像具有更高的清晰度和更丰富的边缘信息. 展开更多
关键词 完整水下成像模型 深度图 红通道最小强度先验 变分模型 交替方向乘子法
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Study on Red Tide Remote Sensing Monitoring in the Bohai Sea in 2014 被引量:5
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作者 ZHANG He ZHENG Xiao-shen 《Marine Science Bulletin》 CAS 2017年第1期37-51,共15页
Since 2000, red tides have been reported in the Bohai Sea every year, whichoften made coastal waters of the Bohai Sea suffering from red tides. Satellite remotesensing technology and the ocean color observation satell... Since 2000, red tides have been reported in the Bohai Sea every year, whichoften made coastal waters of the Bohai Sea suffering from red tides. Satellite remotesensing technology and the ocean color observation satellite images have beensuccessfully used to identify and observe the initiation, evolution, and dissipation of redtide. However, due to different water bodies, remote sensing data and modelingmethods, a specific model of red tide inversion should be established for the watercharacteristics of the Bohai Sea. In this paper, the correlation analysis between MODISspectral reflectivity data and measured concentration of chlorophyll a in the Bohai Seawas carried out. The expression (B10-B8) / (B13-B8) was chosen as the indicator of redtide inversion in the Bohai Sea, the correlation coefficient reached 0.7815, showingsignificant correlation results. It was found that the spatial and temporal distribution ofred tide in the Bohai Sea in 2014 was obvious. The main causes of the large-scale outbreak of red tide in the Bohai Sea are due to the poor water exchange caused by thesemi-enclosed geomorphology and the large amount of terrestrial matter input fromcoastal runoff. The river input is the main source of land-based pollution into the sea.Then, a red tide inversion model based on a modified red tide index was established byusing GOCI remote sensing data with less cloud coverage, and proven effective indelineating the red tide in turbid waters. The hourly RI images on 15, 26 and 28 May2014 showed consistent evolution, and the area of red tide in the Bohai Sea changedsignificantly during one day. Vertical migration of the dominant species of red tide algaemay be the main reason for the short-term changes in the surface expression. 展开更多
关键词 red tide Bohai Sea MODIS GOCI remote sensing diurnal variation
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Microsatellite DNA markers to assess population structure of red tailed barb Gonoproktopterus curmuca 被引量:1
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作者 Achamveettil GOPALAKRISHNAN Kochikkaran Kunjumohammed MUSAMMILU +4 位作者 Peringady Mohammed ABDUL MUNEER Kuldeep Kumar LAL Dhurendra KAPOOR Alphis Geethanand PONNIAH Vindhya MOHINDRA 《动物学报》 SCIE CAS CSCD 北大核心 2004年第4期686-690,共5页
本文检测了三种鲤科鱼的 1 6对微卫星引物在红尾中的适用性 ,其中 6对引物可以成功扩增 ,且 5个位点具有多态性。对采自两条不同河流的标本 ,通过检测这些多态微卫星位点的遗传变异情况 ,评估了它们在红尾种群结构分析的适合性。结果显... 本文检测了三种鲤科鱼的 1 6对微卫星引物在红尾中的适用性 ,其中 6对引物可以成功扩增 ,且 5个位点具有多态性。对采自两条不同河流的标本 ,通过检测这些多态微卫星位点的遗传变异情况 ,评估了它们在红尾种群结构分析的适合性。结果显示这 5个多态位点在上述两个样本中的平均表观杂合度分别是 0 2 93和0 4 71。 展开更多
关键词 red tailed barb Gonoproktopterus curmuca MICROSATELLITE Genetic variation
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Analysis of the inter-annual variability and southward expansion of red tides in the Zhejiang coastal waters from 1981 to 2018 被引量:1
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作者 Lili Xu Yinyu Liang +1 位作者 Wenjun Xiao Bingrui Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第1期132-140,共9页
A time series dataset spanning 39 years(1981-2018) on red tide events in Zhejiang coastal waters was used to study the characteristics of inter-annual spatial and temporal variations. A distinct inter-annual pattern c... A time series dataset spanning 39 years(1981-2018) on red tide events in Zhejiang coastal waters was used to study the characteristics of inter-annual spatial and temporal variations. A distinct inter-annual pattern characterized by low frequency, explosive growth and fluctuating decline stages was found over the studied time scale. Most red tide events occurred in parallel to the bathymetric contour, and 95.4% were located to the west of the 50 m isobath. Additionally, the high-incidence area of red tides is expanding southward. In this paper, local sea surface temperature(SST), mariculture area and secondary industry growth rate are introduced and identified as the main factors influencing the nutrient and hydrometeorological conditions. A multivariate nonlinear regression equation based on these factors was constructed, and the goodness of fit coefficient was 0.907. The causes of the annual variation and high-frequency area in the southward expansion were quantitatively analyzed based on the proposed regression model. Finally, the results indicated that 68.7% of the annual occurrence variation of red tide was due to the SST and mariculture area, which are the main impact factors;however,secondary industry growth could compensate for the nutrient deficiency caused by the sharp mariculture area reduction and decreased SST. The background nutrient level, which is elevated by coastal economic development, especially secondary industry, is the main determinant of the southward expansion. Although the trend of the southward expansion of high-frequency areas has not changed, the red tide frequency in coastal cities has decreased by half and remained at a stable level after 2010 due to substantial economic restructuring and environmental protection. 展开更多
关键词 Zhejiang Province red tide peak drop inter-annual variation southward expansion
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BIFURCATIONS AND CHAOS CONTROL IN TCP-RED SYSTEM
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作者 刘芳 《Journal of Pharmaceutical Analysis》 SCIE CAS 2006年第1期1-5,共5页
Objective Analyzing the nonlinear dynamics of the TCP-RED congestion control system is of great importance. This study will help investigate the loss of stability in Internet and design a proper method for controlling... Objective Analyzing the nonlinear dynamics of the TCP-RED congestion control system is of great importance. This study will help investigate the loss of stability in Internet and design a proper method for controlling bifurcation and chaos in such system. Methods Based on bifurcation diagram, the effect of parameter on system performance is discussed. By using the state feedback and parameter variation strategy, a simple real time control method is proposed to modify the existing RED scheme. Results With our control method, the parametric sensitivity of RED mechanism is attenuated. Moreover, a sufficient condition on the robust stability of the system is also derived to adjust the parameters in TCP-RED system. Conclusion The proposed method has the advantages of simple implementation and unnecessary knowledge of the exact system. 展开更多
关键词 BIFURCATION CHAOS feedback control parameter variation congestion control transfer control protocol (TCP) random early detection (red)
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Egg rejection behavior does not explain the lack of cowbird parasitism on an eastern North American population of Red-winged Blackbirds 被引量:1
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作者 Justin J.Reel Todd J.Underwood 《Avian Research》 CSCD 2019年第4期431-440,共10页
Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not... Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not been recorded as hosts in our study area in southeastern Pennsylvania.Although hosts of Old World cuckoos(Cuculidae)often show geographic variation in egg rejection behavior,cowbird hosts typically exhibit uniform responses of all acceptance or all rejection of cowbird eggs.Thus,geographic variation in cowbird parasitism frequencies might reflect a different behavioral response to parasitism by hosts where only some populations reject parasitism.In this study,we tested whether egg rejection behavior may explain the lack of parasitism observed in our eastern red-wing population,which may provide insight into low parasitism levels across eastern North America.Methods:We parasitized red-wing nests with model cowbird eggs to determine their response to parasitism.Nests were tested across three nest stages and compared to control nests with no manipulations.Because rejection differed significantly by stage,we compared responses separately for each nest stage.We also monitored other songbird nests to identify parasitism frequencies on all potential hosts.Results:Red-wings showed significantly more rejections during the building stage,but not for the laying and incubation stages.Rejections during nest building involved mostly egg burials,which likely represent a continuation of the nest building process rather than true rejection of the cowbird egg.Excluding these responses,red-wings rejected 15%of cowbird eggs,which is similar to rejection levels from other studies and populations.The overall parasitism frequency on 11 species surveyed in our study area was only 7.4%.Conclusions:Egg rejection behavior does not explain the lack of parasitism on red-wings in our eastern population.Alternatively,we suggest that cowbird preference for other hosts and the low abundance of cowbirds in the east might explain the lack of parasitism.Future research should also explore cowbird and host density and the makeup of the host community to explain the low levels of parasitism on red-wings across eastern North America because egg rejection alone is unlikely to explain this broad geographic trend. 展开更多
关键词 Brood parasitism Brown-headed Cowbird Egg rejection Geographic variation red-winged Blackbird
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同型半胱氨酸、红细胞体积分布宽度、糖化血红蛋白变异指数对糖尿病足发生的影响及预测价值 被引量:3
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作者 张琳 龙俊宏 +3 位作者 黄丽丽 田静宇 高菲 李友芳 《中国医药导报》 CAS 2023年第15期73-76,共4页
目的探讨同型半胱氨酸(Hcy)、红细胞体积分布宽度(RDW)、糖化血红蛋白变异指数(HGI)对糖尿病足(DF)发生的影响及预测价值。方法选取2018年6月至2020年6月于西安交通大学第二附属医院内分泌科就诊的2型糖尿病(T2DM)患者166例,按照是否合... 目的探讨同型半胱氨酸(Hcy)、红细胞体积分布宽度(RDW)、糖化血红蛋白变异指数(HGI)对糖尿病足(DF)发生的影响及预测价值。方法选取2018年6月至2020年6月于西安交通大学第二附属医院内分泌科就诊的2型糖尿病(T2DM)患者166例,按照是否合并DF将其分为T2DM组(104例)及DF组(62例)。收集两组临床相关资料及Hcy、RDW水平,并计算HGI。采用二元logistic回归模型分析DF发生的影响因素,绘制受试者操作特征(ROC)曲线并计算曲线下面积(AUC),分析DF的预测指标及其预测价值。结果DF组年龄、糖化血红蛋白、空腹血糖(FBG)、Hcy、RDW、HGI均高于T2DM组,差异有统计学意义(P<0.05)。多因素分析结果显示,FBG、Hcy、RDW、HGI均为DF发生的独立影响因素(P<0.05)。ROC曲线分析结果显示,FBG、Hcy、RDW、HGI单独及联合对DF均有一定的预测价值,各指标联合预测的AUC高于单独预测(P<0.05)。结论FBG、Hcy、RDW、HGI联合预测可作为一种有效的T2DM患者DF治疗及护理介入时机的预测指标。 展开更多
关键词 2型糖尿病 糖尿病足 同型半胱氨酸 红细胞体积分布宽度 糖化血红蛋白变异指数
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南方典型红壤丘陵区泡桐幼苗根系的空间分布特征 被引量:1
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作者 田卓 何建华 +2 位作者 张帅普 代俊峰 徐勤学 《西南农业学报》 CSCD 北大核心 2023年第10期2200-2209,共10页
【目的】分析南方红壤丘陵区白花泡桐[Paulownia fortunei(Seem.)Hemsl.]幼苗根系的空间分布及变异特征,为泡桐栽培及红壤丘陵区植被恢复提供参考依据。【方法】野外调查典型红壤丘陵区对重金属元素具有较强富集作用及可防治水土流失的... 【目的】分析南方红壤丘陵区白花泡桐[Paulownia fortunei(Seem.)Hemsl.]幼苗根系的空间分布及变异特征,为泡桐栽培及红壤丘陵区植被恢复提供参考依据。【方法】野外调查典型红壤丘陵区对重金属元素具有较强富集作用及可防治水土流失的白花泡桐幼苗不同直径(d<0.5 mm、0.5 mm≤d<2.0 mm、2.0 mm≤d<3.0 mm、3.0 mm≤d<5.0 mm和d≥5.0 mm)根系的空间分布规律,分析泡桐幼苗对土壤的适应能力。【结果】在垂直方向上,随着土层深度的增加,泡桐幼苗的根长、根表面积和比根表面积呈先增加后减少的变化趋势,根体积、根干重和根组织密度逐渐减少,比根长逐渐增加;<3.0 mm各径级根系的根体积、根表面积和<5.0 mm各径级根系的根长随着土层深度的增加均呈先增加后减少的变化趋势,其他径级根系的根体积、根表面积和根长逐渐减少。0≤土层深度(h)<10.0 cm土层根表面积和根体积的变异性均显著强于其他土层(P<0.05,下同),根干重的变异性显著强于20.0 cm≤h<50.0 cm各土层;40.0 cm≤h<50.0 cm土层中2.0 mm≤d<5.0 mm各径级根系的根长、根体积和根表面积变异性均显著强于其他土层。在不同水平位置上,<2.0 mm各径级根系的根长、根体积和根表面积在距树干最远的剖面均最大,≥2.0 mm各径级根系的根长、根体积和根表面积在树干所在的剖面均最大。各剖面间根长、根体积、根表面积、根干重、比根长、根组织密度和比根表面积的变异性均无显著差异(P>0.05);各径级根系根长、根体积和根表面积变异性均在距树干最远的剖面最强。【结论】白花泡桐幼苗根系主要集中分布在0~20.0 cm土层,具有明显的表聚现象,在栽培泡桐时,应重点关注0~20.0 cm土层土壤的理化性质,以保证泡桐根系对土壤水肥的高效吸收利用。 展开更多
关键词 泡桐 红壤丘陵区 根系 空间分布 变异特征
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血清Lp-PLA2、RDW-CV、NLR值变化与急性脑梗死患者早期神经功能恶化及预后的关系 被引量:14
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作者 兰翠霞 王健 +1 位作者 王江凤 刘雯馨 《中国现代医学杂志》 CAS 北大核心 2023年第10期12-17,共6页
目的 探讨血清脂蛋白相关磷脂酶A2(Lp-PLA2)、红细胞分布宽度变异系数(RDW-CV)、中性粒细胞与淋巴细胞比值(NLR)与急性脑梗死(ACI)患者早期神经功能恶化及预后康复的关系。方法 选取2018年5月—2022年1月青岛大学附属青岛市海慈医院收治... 目的 探讨血清脂蛋白相关磷脂酶A2(Lp-PLA2)、红细胞分布宽度变异系数(RDW-CV)、中性粒细胞与淋巴细胞比值(NLR)与急性脑梗死(ACI)患者早期神经功能恶化及预后康复的关系。方法 选取2018年5月—2022年1月青岛大学附属青岛市海慈医院收治的90例ACI患者作为ACI组,另取90例无脑血管疾病的体检志愿者作为对照组。对比两组研究对象的Lp-PLA2、RDW-CV、NLR,并按照神经功能缺损程度进行分组比较;按患者治疗3个月后的神经功能恢复情况分为预后良好组、预后不良组,采用一般多因素Logistic回归模型分析Lp-PLA2、RDW-CV、NLR与ACI患者预后结局的关系。结果 ACI组Lp-PLA2、RDW-CV、NLR高于对照组(P <0.05)。NIHSS评分≤15分ACI患者Lp-PLA2、RDW-CV、NLR低于NIHSS评分> 15分ACI患者(P <0.05)。预后良好组Lp-PLA2、RDW-CV、NLR低于预后不良组(P <0.05)。一般多因素Logistic回归分析结果显示:NIHSS评分高[^OR=1.790(95%CI:1.101,2.910)]、梗死病灶大[^OR=1.745(95%CI:1.084,2.810)]、入院时GCS评分低[^OR=0.608(95%CI:0.375,0.986)]、Lp-PLA2升高[^OR=1.677(95%CI:1.068,2.632)]、RDW-CV升高[^OR=1.737(95%CI:1.148,2.626)]、NLR升高[^OR=1.642(95%CI:1.034,2.608)]是ACI患者预后不良的危险因素(P <0.05)。结论 ACI患者血清Lp-PLA2、RDW-CV、NLR水平较非脑血管疾病患者升高,并且与早期神经功能损伤程度及患者不良预后结局关系密切。 展开更多
关键词 急性脑梗死 脂蛋白相关磷脂酶A2 红细胞分布宽度变 中性粒细胞 淋巴细胞 神经功能 预后
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野生小熊猫主食竹叶围细菌的年际变化 被引量:1
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作者 李毅 张泽钧 +3 位作者 康力文 王佳 侯怡薇 洪明生 《四川林业科技》 2023年第3期45-53,共9页
竹叶作为竹林健康状况的重要指示器官,是竹子叶围微生物生存繁衍的重要场所,同时也是病原微生物入侵的重要入口,进而会影响野生小熊猫的健康状况。为了探究野生小熊猫主食竹叶围细菌的年际变化,本文以四川美姑大风顶国家级自然保护区的... 竹叶作为竹林健康状况的重要指示器官,是竹子叶围微生物生存繁衍的重要场所,同时也是病原微生物入侵的重要入口,进而会影响野生小熊猫的健康状况。为了探究野生小熊猫主食竹叶围细菌的年际变化,本文以四川美姑大风顶国家级自然保护区的熊竹(Yushania ailuropodina)为研究对象,通过高通量测序技术探究了熊竹叶围细菌组成、多样性、群落结构的年际变化。研究发现,熊竹叶围细菌11月份OTUs最丰富,且OTUs丰富度秋冬季高于春夏季。12个月份的优势门均为变形菌门(Proteobacteria)、拟杆菌门(Bacteroidota)和酸杆菌门(Acidobacteriota),夏季(6月—8月)的变形菌门(Proteobacteria)相对丰度高于其他月份,但拟杆菌门的相对丰度低于其他月份。夏季(6月—8月)假单胞菌属(Pseudomonas)的相对丰度明显高于其他月份,但1174-901-12的相对丰度低于其他月份。秋季(9月—11月)和冬季(12月—2月)小熊猫主食竹熊竹叶围细菌的丰富度(Sobs index)和多样性(Shannon index)高于其他季节;群落结构(un)weighted Unifrac distances在不同月份间存在一定的差异,其中夏季(6月—8月)的weighted Unifrac距离显著大于其他月份。本研究表明小熊猫主食竹叶围微生物丰富,其组成、多样性、群落结构具有明显的年际变化规律,且主要受季节的影响。本研究可为小熊猫主食竹资源的科学管理提供支撑,为野生小熊猫保护措施的科学制定提供参考依据。 展开更多
关键词 小熊猫 熊竹 叶围细菌 多样性 年际变化
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血清可溶性转铁蛋白受体、红细胞分布宽度-变异系数与维持性血液透析患者铁代谢的关系 被引量:1
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作者 顾铜 方倩 +1 位作者 何阳 李慧妍 《临床肾脏病杂志》 2023年第6期461-466,共6页
目的研究血清可溶性转铁蛋白受体(soluble transferrin receptor,sTFR)、红细胞分布宽度-变异系数(red blood cell distribution width-coefficient of variation,RDW-CV)与维持性血液透析患者铁代谢的关系。方法选取2019年1月至2020年... 目的研究血清可溶性转铁蛋白受体(soluble transferrin receptor,sTFR)、红细胞分布宽度-变异系数(red blood cell distribution width-coefficient of variation,RDW-CV)与维持性血液透析患者铁代谢的关系。方法选取2019年1月至2020年6月秦皇岛市第一医院收治的98例终末期肾病患者,其中48例患者为维持性血液透析患者(A组),48例为非透析终末期肾病患者(B组)。另外,选取同期在秦皇岛市第一医院进行健康体检的受试者48例作为对照组。入组后第二天,测定受试者sTFR水平、RDW-CV水平、肾功能参数水平、铁代谢参数水平。结果A组的sTFR水平为(49.78±17.43)nmol/L、RDW-CV水平为(16.21±2.43)%,均显著高于B组的(31.01±5.23)nmol/L、(14.87±4.88)%和对照组的(13.79±3.72)nmol/L、(12.89±3.92)%(P<0.05)。与B组相比,A组患者的超敏C反应蛋白(high sensitivity C-reactive protein,hs-CRP)、血红蛋白(hemoglobin,Hb)、血清铁蛋白(ferritin,Fer)水平显著增加(P<0.05),白蛋白(albumin,Alb)、血清转铁蛋白(transferrin,TRF)、血清铁及转铁蛋白饱和度(transferrin saturation,TSAT)水平显著降低(P<0.05)。患者血清sTFR和RDW-CV水平均与血肌酐(serum creatinine,Scr)、尿酸(uric acid,UA)、hs-CRP、甲状旁腺激素(parathyroid hormone,PTH)、FER和TSAT水平呈正相关(P<0.05);与估算肾小球滤过率(estimated glomerular filtration rate,eGFR)、红细胞计数(red blood cell,RBC)、Alb、Hb、TRF和血清铁(serum iron,SI)水平呈负相关(P<0.05)。多元逐步回归分析结果显示,维持性血液透析患者血清sTFR、RDW-CV水平与患者铁代谢参数FER和血清总铁结合力水平均有密切关系(P<0.05)。血清sTFR的曲线下面积(area under curve,AUC)和95%置信区间为0.874、0.823~0.909,血清RDW-CV的AUC和95%置信区间为0.888、0.812~0.899。血清sTFR的截断值为32.12 nmol/L,对维持性血液透析患者铁代谢预测的特异性为71.2%,敏感性为76.3%。血清RDW-CV的截断值为15.42%,对维持性血液透析患者铁代谢预测的特异性为68.0%,敏感性为76.4%。结论血清sTFR、RDW-CV水平与维持性血液透析患者的铁代谢水平呈负相关,可以在一定程度上反映患者的铁代谢水平。 展开更多
关键词 可溶性转铁蛋白受体 红细胞分布宽度-变异系数 维持性血液透析 铁代谢
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2009—2019年红壤典型区水稻土有机碳组分库时空变化
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作者 王玺洋 李亮 +3 位作者 李晓晖 辛在军 何石福 孙小艳 《农业环境科学学报》 CAS CSCD 北大核心 2023年第3期589-598,共10页
为及时掌握土壤有机碳组分库的时空变化,本研究基于历史采样信息开展新一轮土壤样品采集,进行100 d土壤呼吸培养实验,借助三库一级动力学模型,获得土壤活性碳库大小(Ca)、缓效性碳库大小(Cs)和惰性碳库大小(Cr),以揭示2009—2019年江西... 为及时掌握土壤有机碳组分库的时空变化,本研究基于历史采样信息开展新一轮土壤样品采集,进行100 d土壤呼吸培养实验,借助三库一级动力学模型,获得土壤活性碳库大小(Ca)、缓效性碳库大小(Cs)和惰性碳库大小(Cr),以揭示2009—2019年江西省东乡地区表层水稻土Ca、Cs和Cr的时空变化及主要影响因子。结果表明:2009—2019年研究区表层水稻土平均总有机碳(TOC)、Ca和Cs减少,而平均Cr增加;TOC、Ca、Cs和Cr的变化速率分别为-0.04、-0.02、-0.07 g·kg^(-1)·a^(-1)和0.05 g·kg^(-1)·a^(-1)(P>0.05)。土壤属性对2019年东乡地区表层水稻土TOC、Ca和Cr的空间变异影响较小,而土壤全氮(TN)对TOC、Cs和Cr的变异均有较大贡献,在制定水稻土固碳措施时,应关注土壤N含量的协同变异。此外,近10年来研究区北部和中部地区水稻土有机碳组分变化幅度较大,而西南和东南地区变化幅度较小,因此,未来红壤区水稻土固碳应重视各有机碳组分的时空分异。 展开更多
关键词 红壤区 活性碳库 缓效性碳库 惰性碳库 时空变异 水稻土固碳
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