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Effects of Different Exogenous Substances on Seed Germination of Isatis indigotica Under Drought Stress and Chemical Composition of Isatis indigotica leaves
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作者 Wang Hao Qin Jingjing +4 位作者 Shi Zhe Song Jiayao Ma Wuqiong Wang Huimin Cao Jinjun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第2期66-75,共10页
This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogeno... This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogenous substances to efficient cultivationof Isatis indigotica. Polyethylene glycol (PEG) was used to simulate drought stress to deal with seeds of Isatis indigotica at thegermination stage (concentration: 0, 10%, 15%, and 20%). Simultaneous operation of exogenous growth regulators [microbialinoculum (MI), γ-aminobutyric acid (GABA) and salicylic acid (SA)] and PEG were implemented in seeds of Isatis indigotica.The effects of drought stress and the mitigation of exogenous substances were observed by statistics of seed germination potential,germination rate, hypocotyl length, and radicle length of each treatment. The effects of exogenous substances on the content ofalkaloids, crude protein and free amino acids in the leaves of Isatis indigotica grown in a greenhouse were determined after sprayingexogenous substances on the plants. The differences of germination potential, germination rate, hypocotyl length, and radicle lengthamong 15% PEG stress treatment, 10% PEG stress treatment and the control were significant (P<0.05). According to the predesignedgermination standard, the seeds did not germinate under 20% PEG stress treatment. When the PEG concentration was 15%, the resultsof seed germination potential and germination rate after adding MI were significantly different from those under stress alone (P<0.05).When exposed to 10% PEG stress, the supplementation of GABA led to a notable increase in radicle length of Isatis indigotica seeds,showing significant differences compared to other three treatments. The application of MI and GABA under 15% PEG stress resultedin a significant increase in the radicle and hypocotyl length of Isatis indigotica seeds compared to other two treatments. The contentof the total alkaloids in leaves of Isatis indigotica was significantly increased after spraying GABA. Meanwhile, the contents of crudeprotein and the total free amino acids were kept constant after spraying exogenous substances. Application of MI and GABA couldalleviate drought stress of Isatis indigotica. The content of the total alkaloids in leaves of Isatis indigotica could significantly increaseafter spraying GABA. 展开更多
关键词 Isatis indigotica Fort. exogenous growth regulator drought stress chemical composition leaves of Isatis indigotica
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Studies on the Flavonoids and Antioxidant Activities in Leaves of Black Currant 被引量:4
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作者 XUYa-qin YUZe-yuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2002年第2期136-140,共5页
The fresh leaves and oven dried leaves from three varieties of black currant (Brodtrop,liangye,Risager)were analysed for the total contents of flavonoids by spectrophotometric methods in terms of rutin equivalent.In ... The fresh leaves and oven dried leaves from three varieties of black currant (Brodtrop,liangye,Risager)were analysed for the total contents of flavonoids by spectrophotometric methods in terms of rutin equivalent.In addition,antioxidant activities of different addition amounts of extracts of black currant (Brodtrop)leaves in lard were measured by the Oven-Storage Test,and compared with the synthetic antioxidants.The results showed the contents of the flavonoids were very rich in the leaves of three varieties from black currant.Among them the leaves of Brodtrop had the highest contents of flavonoids followed by liangye and Risager.The total contents of flavonoids in fresh leaves reach 231 70 mg/100 g,170 01 mg/100 g and 78 07 mg/100 g respectively.In the same circumstance the oven dried leaves were 397 82 mg/100 g,275 89 mg/100 g and 169 73 mg/100 g.The extracts of the leaves from Brodtrop exhibited strong antioxidant activities on lard,which increased with the addition amount of the flavonoid extracts.The antioxidant activities decreased in the order of 0 02% quercetin >0 02% BHT(butylated hydroxy toluene)>0 40% extracts>0 20% extracts>0 10% extracts>0 05% extracts>0 02% extracts>control. 展开更多
关键词 leaves of black currant VARIETIES flavonoid contents LARD antioxidant activity
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Studies on Optimal Extraction Conditions of Flavonoid in Leaves of Black Currnt 被引量:1
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作者 XUYa-qin SUNYan-mei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第2期144-148,共5页
Employing the orthogonal design,the optimal extraction conditions for flavonoid in leaves of black currant were determined by colorimetric estimation,which were extraction agent of 75% EtOH-H 2O,the material ratio(ra... Employing the orthogonal design,the optimal extraction conditions for flavonoid in leaves of black currant were determined by colorimetric estimation,which were extraction agent of 75% EtOH-H 2O,the material ratio(ratio of weight of fresh leaves to volume of the solvent)of 1:16,the temperature of 35℃,the time of 1 h and times of three.A total extraction rate of over 97% and the flavonoid contents of 179 33 mg/100 g were obtained under the optimal extraction conditions. 展开更多
关键词 extraction conditions flavonoid contents leaves of black currant
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Effect of Salt Stress on Nitrogen Assimilation of Functional Leaves and Root System of Rice in Cold Region 被引量:3
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作者 Gu Jiao-jiao Zhao Hong-wei +4 位作者 Jia Yan Hu Bo-wen Wang Zhuo-qian Qu Zhao-jun Yu Feng-li 《Journal of Northeast Agricultural University(English Edition)》 CAS 2020年第2期9-16,共8页
The aims were to investigate the effect of salt stress on key enzyme activity of nitrogen metabolism and the concentration of nitrate nitrogen and ammonium nitrogen response to salt stress.Two rice cultivars,Mudanjian... The aims were to investigate the effect of salt stress on key enzyme activity of nitrogen metabolism and the concentration of nitrate nitrogen and ammonium nitrogen response to salt stress.Two rice cultivars,Mudanjiang 30(sensitive cultivar)and Longdao 5(salt-tolerant cultivar),were treated with different salt concentrations(CK 0%,S10.075%,S20.15%,S30.225%and S40.3%).The results showed that the activities of nitrate reductase(NR),glutamine synthase(GS),glutamate synthase(GOGAT)and glutamate dehydrogenase(GDH)in the functional leaves and roots of rice in cold region presented a single peak curve change and the peak occurred in the heading stage;compared with those of the CK,the activities of NR,GS and GOGAT of rice in cold region decreased,but the activity of GDH increased in the heading stage under salt stress.The variation for key enzyme activity of nitrogen metabolism was the highest under S4 treatment.The activities of NR,GS and GOGAT in the functional leaves significantly decreased compared with those in roots;the concentrations of nitrate nitrogen and ammonium nitrogen in the functional leaves and roots of rice in cold region presented a single peak curve change and the peak occurred in the heading stage;compared with that of the CK,the concentration of nitrate nitrogen decreased in leaves and roots,the concentration of ammonium nitrogen decreased and the concentration of ammonium nitrogen in roots increased under salt stress.The variations for the activities of NR,GS and GOGAT in the functional leaves and roots of Longdao 5 were less than those of Mudanjiang 30 under the same concentration of salt stress. 展开更多
关键词 rice in cold region salt stress functional leave root system nitrogen metabolism
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Elemental Analysis of Tea Leaves (Camellia Sinensis) and Their Own Soils at Eastern Black Sea Region in Turkey
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作者 Canan Aksoy Hatice Kabaoglu +2 位作者 G khan Apayd n Aziz Safi Engin T rasoglu 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第4期1315-1320,共6页
People consume tea brewed from the leaves of the Camellia sinensis plant for about 50 centuries. Health benefits of the tea have been investigated for about three decades. Especially green tea shows antitoxic and lots... People consume tea brewed from the leaves of the Camellia sinensis plant for about 50 centuries. Health benefits of the tea have been investigated for about three decades. Especially green tea shows antitoxic and lots of properties with its determined ingredients. Turkey is not only the one of the best consumer and but also good producer of the tea as being 5 th producer all over the world. It grows eastern region of the Turkey and high quality tea is imported and exported. To have quality tea, grooving soils are also crucial. In the current research, Tea leaves and their own grown soils were collected from 20 stations where the most tea producer cities as Trabzon, Rize and Artvin tea fields of the eastern of Black Sea Region in Turkey. The cultivated tea and their own grown soil samples were analysed by using EDXRF Spectrometry. In the soil samples, the elements Mg, Al, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Ba, Pb on percent level and the elements Mg, Al, Si, P, Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn and Sr in the tea leaves were detected by using SKRAY 3600-EDXRF.and also the obtained data were evaluated with the Kriging interpolation of geostatistical method. Element content were investigated in the soil and tea samples according to the geological situations and also the relation of elemental difference between the tea and the own grown soil. Pb/Zn ratio was also anaysed in the samples. 展开更多
关键词 EASTERN of Black Sea EDXRF Tea leaves SOILS
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Identification and analysis of differentially expressed genes involved in dark-induced photoperiod response and senescence of soybean leaves by suppression subtractive hybridization
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作者 ZHAO Lin1,LUO Qiu-lan1,HAN Ying-peng1,YANG Chun-liang2,LI Wen-bin1(1.Soybean Research Institute(Key Laboratory of Soybean Biology of Chinese Education Ministry),Northeast Agriculture University,Haerbin,China 150030 2.The Basic MedicalScience College,Harbin Medical University,Haerbin,China 150081) 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第S1期222-,共1页
A cDNA subtractive library enriched for dark-induced up-regulated ESTs was constructed by suppression subtractive hybridization(SSH) from leaf tissues of soybean cultivar DongNong L13 treated with short-day(8-h light/... A cDNA subtractive library enriched for dark-induced up-regulated ESTs was constructed by suppression subtractive hybridization(SSH) from leaf tissues of soybean cultivar DongNong L13 treated with short-day(8-h light/16-h dark) and long-day(16-h light/8-h dark) conditions.A total of 148 clones were sequenced,representing 76 unique ESTs which corresponded to about 20% of 738 clones from the cDNA library and showed a significant up-regulation of at least three fold verified by dot blot hybridization.The putative functions of ESTs were predicted by Blastn and Blastx.The 43 differentially expressed genes identified by subtractions were classified according to their putative functions generated by Blast analysis.Genetic functional analysis indicated that putative proteins encoded by these genes were related to diverse functions during organism development,which include biological regulation pathways such as transcription,signal transduction and programmed cell death,protein,nucleic acid and carbohydrate macromolecule degradation,the cell wall modification,primary and secondary metabolism and stress response.Two soybean transcription factors enhanced in SD conditions,GAMYB-binding protein and DNA binding protein RAV cDNAs that may be involved in SD soybean photoperiod response,had been isolated using 5'-and 3'-rapid amplification of cDNA ends(RACE)(Genbank Accession numbers DQ112540 and DQ147914). 展开更多
关键词 cDNA Identification and analysis of differentially expressed genes involved in dark-induced photoperiod response and senescence of soybean leaves by suppression subtractive hybridization ESTs
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m^(6)A modification of lncRNA in middle ear cholesteatoma
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作者 HE Jun XIE Shumin +3 位作者 JIN Li FU Jinfeng YUAN Qiulin LIU Wei 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第5期667-678,共12页
Objective:Middle ear cholesteatoma is a non-tumorous condition that typically leads to hearing loss,bone destruction,and other severe complications.Despite surgery being the primary treatment,the recurrence rate remai... Objective:Middle ear cholesteatoma is a non-tumorous condition that typically leads to hearing loss,bone destruction,and other severe complications.Despite surgery being the primary treatment,the recurrence rate remains high.Therefore,exploring the molecular mechanisms underlying cholesteatoma is crucial for discovering new therapeutic approaches.This study aims to explore the involvement of N6-methyladenosine(m^(6)A)methylation in long non-coding RNAs(lncRNAs)in the biological functions and related pathways of middle ear cholesteatoma.Methods:The m^(6)A modification patterns of lncRNA in middle ear cholesteatoma tissues(n=5)and normal post-auricular skin tissues(n=5)were analyzed using an lncRNA m^(6)A transcriptome microarray.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses were conducted to identify potential biological functions and signaling pathways involved in the pathogenesis of middle ear cholesteatoma.Methylated RNA immunoprecipitation(MeRIP)-PCR was used to validate the m^(6)A modifications in cholesteatoma and normal skin tissues.Results:Compared with normal skin tissues,1525 lncRNAs were differentially methylated in middle ear cholesteatoma tissues,with 1048 showing hypermethylation and 477 showing hypomethylation[fold change(FC)≥3 or<1/3,P<0.05].GO enrichment analysis indicated that hypermethylated lncRNAs were involved in protein phosphatase inhibitor activity,neuron-neuron synapse,and regulation ofα-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid(AMPA)receptor activity.Hypomethylated lncRNAs were associated with mRNA methyltransferase activity,secretory granule membrane,and mRNA methylation.KEGG analysis revealed that hypermethylated lncRNAs were mainly associated with 5 pathways:the Hedgehog signaling pathway,viral protein interaction with cytokines and cytokine receptors,mitogen-activated protein kinase(MAPK)signaling pathway,cytokine-cytokine receptor interaction,and adrenergic signaling in cardiomyocytes.Hypomethylated lncRNAs were mainly involved in 4 pathways:Renal cell carcinoma,tumor necrosis factor signaling pathway,transcriptional misregulation in cancer,and cytokine-cytokine receptor interaction.Additionally,MeRIP-PCR confirmed the changes in m^(6)A methylation levels in NR_033339,NR_122111,NR_130744,and NR_026800,consistent with microarray analysis.Real-time PCR also confirmed the significant upregulation of MAPK1 and NF-κB,key genes in the MAPK signaling pathway.Conclusion:This study reveals the m^(6)A modification patterns of lncRNAs in middle ear cholesteatoma,suggests a direction for further research into the role of lncRNA m^(6)A modification in the etiology of cholesteatoma.The findings provide potential therapeutic targets for the treatment of middle ear cholesteatoma. 展开更多
关键词 long non-coding RNA m6A modifications middle ear cholesteatoma
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养殖RFID测温定位电子耳标研究——基于智慧农业区块链 被引量:2
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作者 刘淑芝 《农机化研究》 北大核心 2025年第2期181-185,共5页
首先,介绍了区块链和物联网技术在智慧农业应用的概念;然后,基于结构、温度传感器、RSSI定位和天线等多个模块实现了对测温定位电子耳标的设计;最后,为了验证该RFID测温定位电子耳标的性能,设计了一套放养羊群的养殖信息监测系统,对每... 首先,介绍了区块链和物联网技术在智慧农业应用的概念;然后,基于结构、温度传感器、RSSI定位和天线等多个模块实现了对测温定位电子耳标的设计;最后,为了验证该RFID测温定位电子耳标的性能,设计了一套放养羊群的养殖信息监测系统,对每只羊的实际位置和体温进行监测。测试结果表明:系统可以准确测量山羊的体温和位置,响应快,稳定性高,符合设计需求。 展开更多
关键词 养殖 测温定位 电子耳标 RFID 智慧农业 区块链
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天马国家级自然保护区落叶阔叶林主要树种空间分布格局及其关联性 被引量:1
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作者 陶涛 光太俊 +3 位作者 黄庆丰 唐雪海 欧强新 刘华 《浙江农林大学学报》 北大核心 2025年第3期544-553,共10页
【目的】探讨中国亚热带北缘向暖温带过渡地带落叶阔叶林主要树种的空间分布格局及其关联性。【方法】以天马国家级自然保护区落叶阔叶林为对象,采用相邻格子法划分9个24 m×24 m的样方,记载样地内胸径(DBH)≥2.5cm的树种名称和空... 【目的】探讨中国亚热带北缘向暖温带过渡地带落叶阔叶林主要树种的空间分布格局及其关联性。【方法】以天马国家级自然保护区落叶阔叶林为对象,采用相邻格子法划分9个24 m×24 m的样方,记载样地内胸径(DBH)≥2.5cm的树种名称和空间坐标;用重要值确定主要树种。运用空间点格局O-ring函数、完全空间随机零模型和异质泊松零模型分析主要树种的空间分布格局及其关联性。【结果】天马国家级自然保护区马鬃岭区共有17科20属27种,优势树种为短柄枹栎Quercus serrata、茅栗Castanea seguinii,亚优势树种为化香Platycarya strobilacea。林木直径结构呈现倒“J”型分布。空间分布格局结果表明:优势树种在0~30 m尺度起初呈现聚集分布,随着尺度的增大,其空间分布格局逐渐趋向于不规则随机分布。种间空间关联性分析发现:枹栎、茅栗和化香3种优势树种之间关联性不显著,但3种优势树种与伴生树种在一定尺度上存在关联性。【结论】该群落类型为典型异龄林栎类与化香落叶阔叶林,短柄枹栎林内更新较好,具有增长趋势,而茅栗、化香林内更新较差,增长趋势不明显。随着群落演替,喜光稍耐阴树种将会逐步替代喜光树种。 展开更多
关键词 落叶阔叶林 空间分布格局 种间关联 北亚热带
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基于AW-CPSO-Fuzzy-PID的茶鲜叶分级输送速度控制器研究 被引量:1
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作者 胡永光 靳筱天 +2 位作者 张志 鹿永宗 潘庆民 《农业机械学报》 北大核心 2025年第4期275-283,共9页
为解决基于机器视觉的茶鲜叶分级输送速度控制精度低的问题,本文设计一种引入自适应权重与Circle混沌映射的PSO优化模糊PID控制器(AW-CPSO-Fuzzy-PID),并开展基于改进模糊PID的茶鲜叶分级输送速度控制。在茶鲜叶输送传动系统作业过程中... 为解决基于机器视觉的茶鲜叶分级输送速度控制精度低的问题,本文设计一种引入自适应权重与Circle混沌映射的PSO优化模糊PID控制器(AW-CPSO-Fuzzy-PID),并开展基于改进模糊PID的茶鲜叶分级输送速度控制。在茶鲜叶输送传动系统作业过程中,当设定输送速度为78.5 mm/s时,每1 ms记录一次,输送速度波动可控制在0.7 mm/s内;改进模糊PID茶鲜叶输送传动系统响应时间比传统PID与模糊PID分别减少81.41%、61.74%;超调量分别降低81.24%、41.82%;采集目标图像平均峰值信噪比分别提高5.8、10.4 dB。结果表明,本文提出的方法具有更好的寻优性能和收敛速度。研究结果为基于机器视觉的茶鲜叶自动分级系统精确而稳定的控制奠定了理论基础,为解决由输送速度波动导致的图像模糊问题提供了技术方案。 展开更多
关键词 茶鲜叶分级 输送速度 模糊PID控制 粒子群算法
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国际视野中的生育休假制度:比较与借鉴 被引量:2
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作者 杨雪燕 唐玲 崔伟芳 《西北人口》 北大核心 2025年第1期72-86,共15页
文章分别从政策理念、政策目标、政策内容、政策效果四个要素构建生育休假制度分析框架,采用瑞典、丹麦、德国、意大利、英国、美国、日本、韩国和中国有关生育休假制度的二手数据,对不同福利类型国家的生育休假制度进行对比和分析。研... 文章分别从政策理念、政策目标、政策内容、政策效果四个要素构建生育休假制度分析框架,采用瑞典、丹麦、德国、意大利、英国、美国、日本、韩国和中国有关生育休假制度的二手数据,对不同福利类型国家的生育休假制度进行对比和分析。研究发现,社会福利制度类型深刻影响各国生育休假制度理念,在不同的政策理念影响下,各国在政策目标、政策内容、政策效果方面存在明显差异。当前的生育休假制度的设计理念主要包括“普惠性-双职工”与“补缺性-男性单职工”两种模式;但是随着世界人口与政治形势的变化,两种模式的福利类型国家在操作化层面有趋同的趋势;不同福利类型的国家和地区在生育休假制度目标设计上同时涵盖提升总和生育率与促进女性就业率,但在具体的生育休假期限与生育休假成本分担机制的设计上存在差异;当国家在生育休假成本分担中呈现主体地位时,其总和生育率与女性就业率均呈现出更为积极的发展态势,反之亦反。基于研究结果,建议遵循“普惠性-双职工模式”的政策理念、确定提升生育率和女性就业率双重政策目标、合理设计生育休假期限、彰显国家在生育休假成本分担机制当中的主导作用,以完善我国生育休假制度、促进家庭分工平衡、减轻家庭和企业生育负担、营造生育友好环境。 展开更多
关键词 生育休假制度 社会政策分析 国际比较 借鉴
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施氮量与留叶数互作对红花大金元上部叶质量和可用性的影响 被引量:1
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作者 王德勋 刘心亚 +5 位作者 李娟 赵园园 夏玉兰 杨帆 赵东杰 史宏志 《江西农业学报》 2025年第2期51-58,共8页
为探究施氮量与留叶数互作对红花大金元上部叶质量和可用性的影响,以红花大金元为试验材料,设置了施氮量为90、108和126 kg/hm^(2),留叶数为16、18、20和22片/株的双因素田间试验,共12个处理。结果表明,相同留叶数水平下,随着施氮量水... 为探究施氮量与留叶数互作对红花大金元上部叶质量和可用性的影响,以红花大金元为试验材料,设置了施氮量为90、108和126 kg/hm^(2),留叶数为16、18、20和22片/株的双因素田间试验,共12个处理。结果表明,相同留叶数水平下,随着施氮量水平的增加,上部叶的产量和产值增加,烟碱、总氮、钾离子含量总体升高,糖碱比总体下降,中等施氮量水平下感官品质总分相对较高;中、高氮处理的各种致香成分含量和香气成分总量相比低氮处理均有不同程度的增加。相同施氮量水平下,随着留叶数的增加,上部叶的单叶重和产量显著下降,上等烟比例和均价先升高后降低,烟碱、总氮和氯离子含量下降,总糖、还原糖和钾离子含量增加,糖碱比和钾氯比显著上升;香气成分总量、新植二烯和类胡萝卜素降解产物含量随着单株留叶数的增加而下降,非酶棕色化反应产物、苯丙氨酸裂解产物和茄酮含量则升高;中、高施氮量水平下均以留叶数为18片/株的感官评分总分最高。两者的交互作用对上部叶经济性状、物理特性、化学成分和部分香气物质含量有显著影响,施氮量108 kg/hm^(2)+留叶数18片/株为较合理的栽培组合,上部叶的产值高、感官品质优、中性香气物质足、工业可用性高。 展开更多
关键词 红花大金元 施氮量 留叶数 上部叶 质量
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耳穴压豆改善子宫肌瘤腹腔镜术后胃肠功能及胃肠激素水平的疗效研究
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作者 黄锦华 张文烨 +5 位作者 尤晓凤 肖静 郑柳榕 刘继来 王玫 向姝静 《重庆医科大学学报》 北大核心 2025年第4期516-522,共7页
目的:观察耳穴压豆对子宫肌瘤患者腹腔镜术后胃肠动力及相关激素的影响,探讨耳穴压豆的疗效机制。方法:选取2022年5月至2023年12月于福建中医药大学附属人民医院妇科行腹腔镜子宫肌瘤剔除术的患者,采用随机数字表法分成试验组与对照组,... 目的:观察耳穴压豆对子宫肌瘤患者腹腔镜术后胃肠动力及相关激素的影响,探讨耳穴压豆的疗效机制。方法:选取2022年5月至2023年12月于福建中医药大学附属人民医院妇科行腹腔镜子宫肌瘤剔除术的患者,采用随机数字表法分成试验组与对照组,每组57例。试验组采用术后常规护理+耳穴压豆(脾、胃、交感)治疗,对照组采用术后常规护理+假耳穴压豆(脾、胃、交感,不含王不留行籽)治疗。比较2组患者术后的首次排气排便时间、临床疗效和胃肠激素水平变化。结果:试验组的术后首次排气时间[20.31(17.52,22.38) h vs.21.51(18.53,28.15) h]、排便时间[35.32(31.47,39.17) h vs.38.12(33.44,42.78) h]均低于对照组(P<0.05);试验组的临床疗效优于对照组(P<0.05);2组术前的胃动素(motilin,MTL)、胃泌素(gastrin,GAS)、生长抑素(somatostatin,SS)和P物质(substance P,SP)水平差异无统计学意义(P>0.05),MTL和GAS在术后呈上升趋势,SS和SP呈下降趋势。试验组术后24 h的MTL[(451.52±54.33) pg/mL vs.(476.24±56.35) pg/mL]、GAS[150.50(133.93,164.52) pg/mL vs.173.44(154.45,184.63) pg/mL]水平均低于对照组(P<0.05),术后24 h的SS[38.34(33.24,40.23) pg/mL vs.33.36(29.13,38.76) pg/mL]水平高于对照组(P<0.05),而SP水平的变化差异无统计学意义(P>0.05)。重复测量方差分析和广义估算方程结果显示,MTL时间效应和交互效应差异有统计学意义(P<0.05);SP的时间效应差异有统计学意义(P<0.05);GAS和SS的时间效应、组间效应和交互效应差异均有统计学意义(P<0.05)。结论:耳穴压豆对子宫肌瘤患者腹腔镜术后腹胀的疗效明显,可有效调节患者的胃动力相关激素水平,促进患者胃肠功能恢复。 展开更多
关键词 腹腔镜 子宫肌瘤 腹胀 胃肠激素 耳穴压豆
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组合式柔性低损玉米摘穗装置的设计与仿真分析
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作者 屈哲 邵海昊 +5 位作者 王喜龙 乐金涛 赵慧慧 王万章 张红梅 杨立权 《农机化研究》 北大核心 2025年第8期17-24,共8页
探究了柔性低损玉米摘穗装置和不同参数的浮动弹簧在摘穗过程中对玉米果穗受力的影响,旨在降低摘穗板与拉茎辊组合式摘穗装置在收获过程中造成的玉米果穗的损伤和损失。通过分析摘穗过程中玉米果穗的受力情况,发现弹簧刚度系数和阻尼系... 探究了柔性低损玉米摘穗装置和不同参数的浮动弹簧在摘穗过程中对玉米果穗受力的影响,旨在降低摘穗板与拉茎辊组合式摘穗装置在收获过程中造成的玉米果穗的损伤和损失。通过分析摘穗过程中玉米果穗的受力情况,发现弹簧刚度系数和阻尼系数对果穗受力有显著影响。同时,研究了玉米果穗与茎秆的物理力学特性,提出了采用组合式柔性毛刷、被动式浮动摘穗板、分段式摘穗板和摘穗板间隙自适应调节装置的设计方案。利用ADAMS软件进行虚拟运动仿真试验,分析了不同弹簧刚度系数和阻尼系数对玉米果穗与摘穗板碰撞力的影响,并将仿真结果导入Design-Expert中得到最优参数组合。通过计算可知:当浮动弹簧刚度系数为56.25 N/m、阻尼系数为33.5 N·s/m时,玉米果穗与摘穗板的碰撞力最小,为1040.11 N。研究结果表明:通过改变玉米摘穗装置的结构和将部分装置柔性化,可以有效减小玉米果穗与摘穗板碰撞的瞬间力,减少玉米果穗收获过程中的损伤与损失,从而为低损玉米摘穗装置的研发提供研究依据和理论参考。 展开更多
关键词 玉米 摘穗装置 柔性 低损 ADAMS仿真
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烟稻复种区上部烟叶一次性采收成熟度及经济与品质效应
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作者 李旭 金江华 +9 位作者 蒋宇丽 张守荣 于大鹏 崔日男 秦凌 成勍松 秦李俊 卿俊翔 旷子扬 邓小华 《西南农业学报》 北大核心 2025年第3期479-487,共9页
[目的]探寻烤烟上部6片烟叶一次性采收适宜成熟度及不同采收成熟度的烟叶品质和经济效应,为提高上部烟叶高可用性提供技术支撑。[方法]以云烟87为材料,设计低(M_(1))、中(M_(2))、高(M_(3))3个成熟度处理,研究不同成熟度鲜烟叶成熟特征... [目的]探寻烤烟上部6片烟叶一次性采收适宜成熟度及不同采收成熟度的烟叶品质和经济效应,为提高上部烟叶高可用性提供技术支撑。[方法]以云烟87为材料,设计低(M_(1))、中(M_(2))、高(M_(3))3个成熟度处理,研究不同成熟度鲜烟叶成熟特征及上部烟叶一次性采收的经济和品质效应。[结果](1)鲜烟叶成熟度与单叶质量、叶片厚度、叶面积质量、淀粉呈显著负相关,与外观质量指数、总糖、还原糖、烟碱呈显著正相关,对烟叶评吸质量的影响大于外观质量,对烟叶理化性状影响大于经济性状,主要影响单叶质量、叶片厚度和淀粉3个指标。(2)上部烟叶一次性采收成熟度提高,鲜烟叶的叶面由黄绿变全黄、茸毛脱落增加、表面粘手感增强、叶脉由绿变白、成熟斑增多、鲜烟叶SPAD值(叶绿素的相对含量)下降。(3)上部烟叶中等成熟度采收(M_(2)处理)较M_(1)、M_(3)处理的正组烟叶比例分别提高13.00、3.53个百分点,上等烟率分别提高14.00、7.29个百分点,杂色烟叶比例分别降低9.10、2.41个百分点,微带青烟叶比例分别降低3.91、1.22个百分点。(4)随上部烟叶采收成熟度提高,烤后烟叶的叶片结构疏松、油分增加、色度增强、叶片变薄、单叶质量下降、糖含量和两糖比及糖碱比升高、淀粉含量下降。(5)上部叶中等成熟度采收(M_(2)处理)的烟叶香气量尚足,清晰度中等,但稍有口腔干燥感,整体表现尚协调;高成熟度(M_(3))采收的上部叶枯焦杂气稍有显露,烟香透发度略有下降;M_(2)处理较M_(1)、M_(3)处理评吸总分分别高1.58%、3.20%。[结论]湖南烟稻复种烟区云烟87的上部6片烟叶一次性采收要求叶面黄绿(变黄程度70%~80%)、主脉全白、支脉部分变白(变白程度2/3)、茸毛部分脱落、有成熟斑(主要在叶尖部分)、SPAD值在13.03~24.71为适宜成熟度。 展开更多
关键词 烤烟上部烟叶 一次性采收成熟度 烟叶品质 经济性状 灰色关联分析
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非编码RNA在中耳胆脂瘤中的研究进展
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作者 王建涛 朱庆文 王宝山 《中华耳科学杂志》 北大核心 2025年第4期597-602,共6页
中耳胆脂瘤是耳鼻喉科常见疾病,近年来,其临床重要性日益凸显。数据显示,该病的年发病率为10/10万。目前临床上尚无有效的非手术治疗方法,且术后复发率高达40%。若未及时诊断和干预,可导致各种颅内、外并发症。胆脂瘤形成的发病机制研... 中耳胆脂瘤是耳鼻喉科常见疾病,近年来,其临床重要性日益凸显。数据显示,该病的年发病率为10/10万。目前临床上尚无有效的非手术治疗方法,且术后复发率高达40%。若未及时诊断和干预,可导致各种颅内、外并发症。胆脂瘤形成的发病机制研究多聚焦于细胞增殖、细胞凋亡及骨破坏等方面。多种非编码RNA因其在基因表达、细胞周期调节和疾病发生发展中的关键作用而备受关注,其中microRNA、长链非编码RNA和环状RNA的研究尤为深入。本文对非编码RNA在中耳胆脂瘤中的作用机制研究进展作一综述。 展开更多
关键词 中耳胆脂瘤 非编码RNA MICRORNA 环状RNA 长链非编码RNA
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超微粉碎对芹菜叶粉品质及加工特性影响研究
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作者 刘琳琳 李诗雨 +2 位作者 吕铭守 孙冰玉 石彦国 《中国调味品》 北大核心 2025年第5期129-136,共8页
芹菜叶中富含多种营养成分,其维生素C、总酚和黄酮的含量均高于芹菜茎中的含量,同时芹菜叶中含有大量酸性成分,具有平肝降压的功效。但由于芹菜叶易腐烂,储存期较短,利用率较低,易造成资源的浪费。该实验以芹菜叶为原料制备速溶芹菜叶粉... 芹菜叶中富含多种营养成分,其维生素C、总酚和黄酮的含量均高于芹菜茎中的含量,同时芹菜叶中含有大量酸性成分,具有平肝降压的功效。但由于芹菜叶易腐烂,储存期较短,利用率较低,易造成资源的浪费。该实验以芹菜叶为原料制备速溶芹菜叶粉,通过研究柠檬酸添加量、浸泡时间、漂烫温度、漂烫时间等前处理条件对芹菜叶护色效果的影响,确定最优前处理条件。在最优前处理条件下对芹菜叶进行超微粉碎,研究超微粉碎对芹菜叶粉品质特性和加工特性的影响。实验结果表明,芹菜叶最优的前处理条件为柠檬酸添加量0.85%、浸泡时间5 min、漂烫温度90℃、漂烫时间1.6 min。在最优前处理条件下,芹菜叶超微粉碎至300目时,可获得品质较好、速溶率较高的芹菜叶粉制品。该研究充分利用芹菜叶资源,为芹菜叶深加工和新产品的开发提供了理论依据。 展开更多
关键词 芹菜叶 超微粉碎技术 品质特性
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突发性聋患者睡眠状况及与临床特征的相关性分析
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作者 刘静 赵诺 +2 位作者 郭菲菲 李志红 王大勇 《中华耳科学杂志》 北大核心 2025年第7期817-823,共7页
目的了解突发性聋患者睡眠状况及其与临床特征的关系。方法选取2023年5月至2024年1月在中国人民解放军总医院耳鼻咽喉头颈外科医学部耳内科收治的突聋患者101例,年龄18~65岁。采用一般情况调查问卷、匹兹堡睡眠质量指数量表(pittsburgh ... 目的了解突发性聋患者睡眠状况及其与临床特征的关系。方法选取2023年5月至2024年1月在中国人民解放军总医院耳鼻咽喉头颈外科医学部耳内科收治的突聋患者101例,年龄18~65岁。采用一般情况调查问卷、匹兹堡睡眠质量指数量表(pittsburgh sleep quality index,PSQI)、耳鸣残障评估量表(tinnitus handicap inventory,THI)、眩晕评估问卷(dizziness handicap inventory,DHI)、耳闷视觉模拟评估量表(visual analogue scale,VAS)、听觉过敏调查问卷(hyperacusis questionnaire,HQ)、焦虑自评量表(self-rating anxiety scale,SAS)对患者展开调查。结果突发性聋患者的PSQI得分为(7.53±4.45)分,睡眠质量差(PSQI>7分)患者占比为45.6%,性别(t=-2.389,P=0.019)、是否伴随声敏感(t=2.348,P=0.021)、是否合并偏头痛(t=2.792,P=0.006)是突发性聋患者睡眠的影响因素,睡眠质量差亚组患者合并耳鸣(Z=3.267,P=0.001)、耳闷(Z=2.054,P=0.04)、声敏感(Z=2.091,P=0.037)、焦虑(Z=3.892,P<0.01)的人数更多、等级更高;睡眠质量不同两亚组患者听力损失程度、听力曲线类型差异无统计学意义(Z=0.778、0.092,P=0.436、0.927)。结论近半数突发性聋患者存在睡眠问题,有睡眠问题的患者受疾病影响更重,应特别关注睡眠质量差的患者,帮助患者有效应对,降低疾病影响,改善生活质量。 展开更多
关键词 突发性聋 睡眠 耳鸣 耳闷 声敏感 焦虑
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人工饲料育和桑叶育对家蚕不同组织消化酶活性及其基因表达的影响
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作者 杨伟克 杨丽莎 +5 位作者 王永生 Syed Ahmed Zia 杨海 袁亚杰 陈松 朱水芬 《西南农业学报》 北大核心 2025年第3期655-660,共6页
【目的】研究人工饲料育和桑叶育对5龄家蚕不同组织相关消化酶活性及其编码基因表达变化的影响,以期揭示饲料育与桑叶育对家蚕机体消化代谢的生理差异。【方法】利用紫外分光光度法测定饲料育和桑叶育家蚕不同组织脂肪酶、a-淀粉酶和类... 【目的】研究人工饲料育和桑叶育对5龄家蚕不同组织相关消化酶活性及其编码基因表达变化的影响,以期揭示饲料育与桑叶育对家蚕机体消化代谢的生理差异。【方法】利用紫外分光光度法测定饲料育和桑叶育家蚕不同组织脂肪酶、a-淀粉酶和类胰蛋白酶的活性差异,实时荧光定量PCR检测消化酶基因BmLip-1、Bm Amy1和BmTryp的表达情况。【结果】与桑叶饲育组家蚕相比,人工饲料育家蚕脂肪体和中肠脂肪酶、a-淀粉酶活性显著降低,血淋巴的脂肪酶和a-淀粉酶活性有一定程度的降低,但差异不显著;血淋巴和中肠类胰蛋白酶活性极显著增高,脂肪体类胰蛋白酶活性无显著变化。实时荧光定量PCR分析结果表明,BmLip-1和BmAmy1的表达量仅在饲料育家蚕脂肪体组织中显著高于桑叶饲育组,这与其酶活性变化差异趋势相反。BmTryp的表达量在饲料育家蚕血淋巴和中肠组织中显著或极显著高于桑叶饲育组,这与酶活性变化差异趋势一致。【结论】人工饲料育和桑叶育家蚕不同组织消化酶活性及其相关编码基因相对表达量存在差异,这些差异为筛选和培育人工饲料适应性优良家蚕新品种提供新思路。 展开更多
关键词 人工饲料 桑叶 家蚕 消化酶活性 基因表达
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微藻-桑叶复合粉对芦花鸡生产性能、蛋品质、胆固醇及DHA沉积的影响 被引量:1
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作者 彭津津 陈亚强 《中国饲料》 北大核心 2025年第2期117-120,共4页
文章旨在探讨微藻-桑叶复合粉对芦花鸡生长性能,蛋品质,胆固醇及DHA沉积的影响。试验选用400羽健康的28周龄芦花鸡,采用4×2(微藻粉×桑叶粉)完全随机试验设计分成8组,每组5个重复,每个重复10羽鸡。微藻粉按照0%、1%、3%、5%,... 文章旨在探讨微藻-桑叶复合粉对芦花鸡生长性能,蛋品质,胆固醇及DHA沉积的影响。试验选用400羽健康的28周龄芦花鸡,采用4×2(微藻粉×桑叶粉)完全随机试验设计分成8组,每组5个重复,每个重复10羽鸡。微藻粉按照0%、1%、3%、5%,桑叶粉按照2%、4%添加到基础日粮,预饲期1周,试验期4周。结果表明,复合粉对芦花鸡产蛋率、蛋均重、日均采食量、料蛋比等生产性能指标和蛋形指数、蛋白高度、蛋壳强度、蛋壳厚度等蛋品质指标均无显著影响(P> 0.05),但能显著提高蛋黄颜色和哈氏单位(P <0.05),微藻粉单、桑叶粉单独添加还是协同效应均能显著降低蛋黄胆固醇含量(P <0.05),复合粉极显著提高蛋黄DHA含量(P <0.01)。由此可见,在芦花鸡日粮中添加复合粉,能显著降低蛋黄胆固醇含量,大幅提高鸡蛋DHA沉积,为功能性鸡蛋开发提供参考。 展开更多
关键词 微藻-桑叶复合粉 芦花鸡 生长性能 蛋品质 DHA沉积
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