期刊文献+

二次检索

题名
关键词
文摘
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到171,321篇文章
< 1 2 250 >
每页显示 20 50 100
Exogenous calcium enhances the physiological status and photosynthetic capacity of rose under drought stress
1
作者 Xiaojuan Zhao Shang Lin +5 位作者 Shuang Yu Yichang Zhang Lin Su Lifang Geng Chenxia Cheng Xinqiang Jiang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期853-865,共13页
Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related ... Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related properties of rose under polyethylene glycol 6000(PEG6000)-induced drought stress.Chlorophyll levels,as well as leaf and root biomass,were significantly reduced by drought;drought also had a major effect on the enzymatic antioxidant system and increased concentrations of reactive oxygen species.Application of exogenous Ca^(2+)increased the net photosynthetic rate and stomatal conductance of leaves,enhanced water-use efficiency,and increased the length and width of stomata following exposure to drought.Organ-specific physiological responses were observed under different concentrations of Ca^(2+).Application of 5 mmol·L^(-1)Ca^(2+)promoted photosynthesis and antioxidant activity in the leaves,and application of 10 mmol·L^(-1)Ca^(2+)promoted antioxidant activity in the roots.Application of exogenous Ca^(2+)greatly enhanced the phenotype and photosynthetic capacity of potted rose plants following exposure to drought stress.Overall,our findings indicate that the application of exogenous Ca^(2+)enhances the drought resistance of roses by promoting physiological adaptation and that it could be used to aid the cultivation of rose plants. 展开更多
关键词 Rosa hybrida L. exogenous calcium Drought stress Physiological index Photosynthetic capacity
下载PDF
Exogenous insulin autoimmune syndrome:A case report and review of literature
2
作者 Ling-Ling Xu Jia-Xin Chen +1 位作者 Jing-Ping Cheng Ni Luo 《World Journal of Clinical Cases》 SCIE 2024年第9期1691-1697,共7页
BACKGROUND Insulin autoimmune syndrome(IAS)is a severe manifestation of spontaneous hypoglycemia.It is characterized by elevated levels of immune-reactive insulin and highly potent insulin autoantibodies(IAAs),which a... BACKGROUND Insulin autoimmune syndrome(IAS)is a severe manifestation of spontaneous hypoglycemia.It is characterized by elevated levels of immune-reactive insulin and highly potent insulin autoantibodies(IAAs),which are induced by endogenous insulin circulating in the bloodstream.It is distinguished by recurring instances of spontaneous hypoglycemia,the presence of IAA within the body,a substantial elevation in serum insulin levels,and an absence of prior exogenous insulin administration.Nevertheless,recent studies show that both conventional insulin and its analogs can induce IAS episodes,giving rise to the notion of nonclassical IAS.Therefore,more attention should be paid to these diseases.CASE SUMMARY In this case report,we present a rare case of non-classical IAS in an 83-year-old male patient who present with symptoms of a psychiatric disorder.Upon symptom onset,the patient exhibited Whipple's triad(including hypoglycemia,blood glucose level less than 2.8 mmol/L during onset,and rapid relief of hypoglycemic symptoms after glucose administration).Concurrently,his serum insulin level was significantly elevated,which contradicted his C-peptide levels.After a comprehensive examination,the patient was diagnosed with exogenous insulin autoimmune syndrome.Considering that the patient had type 2 diabetes mellitus and a history of exogenous insulin use before disease onset,it was presumed that non classical IAS was induced by this condition.The PubMed database was used to search for previous cases of IAS and non-classical IAS to analyze their characteristics and treatment approaches.CONCLUSION The occurrence of non-classical IAS is associated with exogenous insulin or its analogs,as well as with sulfhydryl drugs.Symptoms can be effectively alleviated through the discontinuation of relevant medications,administration of hormones or immunosuppressants,plasma exchange,and lifestyle adjustments. 展开更多
关键词 Insulin autoimmune syndrome Type 2 diabetes exogenous insulin Insulin autoantibodies HYPOGLYCEMIA Case report
下载PDF
Effects of Different Exogenous Substances on Seed Germination of Isatis indigotica Under Drought Stress and Chemical Composition of Isatis indigotica leaves
3
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
下载PDF
QTL Mapping for the Sensitivity of the Traits Related to Outcrossing of Japonica Rice to Exogenous GA_3 被引量:6
4
作者 付淑换 郭媛 +2 位作者 刘健 徐奇 洪德林 《Agricultural Science & Technology》 CAS 2010年第2期52-56,136,共6页
[Objective] The research aimed to map QTL for the sensitivity of the traits related outcrosssing of Japonica rice to exogenous GA3 and provide theoretical basis for breeding and improving the high-sensitivity sterile ... [Objective] The research aimed to map QTL for the sensitivity of the traits related outcrosssing of Japonica rice to exogenous GA3 and provide theoretical basis for breeding and improving the high-sensitivity sterile line.[Method] Taking Japonica rice Xiushui 79 and C bao and their recombinant inbred line population 260 lines as test materials,the sensitivity of 4 traits related outcrossing to Exogenous GA3 and their QTL mapping were studied by using composite interval mapping..[Result]Three QTLs,which cont... 展开更多
关键词 Japonica rice Traits related outcrosssing exogenous GA3
下载PDF
Effects of Exogenous Hormones on Subculture Multiplication and Root Induction of Tissuecultured Seedlings of Mulberry 被引量:2
5
作者 朱宏 韦鹏霄 +2 位作者 岑秀芬 植菊芳 周芳芳 《Agricultural Science & Technology》 CAS 2014年第5期760-764,共5页
Objective The purpose of this experiment was to investigate the effects of exogenous hormone factors on subculture multiplication and root induction of tis-suecultured seedlings in mulberry. [Method] The aseptic seedl... Objective The purpose of this experiment was to investigate the effects of exogenous hormone factors on subculture multiplication and root induction of tis-suecultured seedlings in mulberry. [Method] The aseptic seedlings of Guisangyou 12 were used as the materials and the comparative experiment on subculture multi-plication and root induction used different kinds,concentrations and combinations of exogenous hormones. [Result] The hormone combination of 0.1 mg/L IBA+1.5 mg/L 6-BA+0.03 mg/L TDZ showed the best effects to bud multiplication, and the multiple of bud multiplication was 5.28. The effects of NAA was better than IBA and IAA on root induction. The hormone combination of 2.0 mg/L NAA+1.0 mg/L PP333 was most suitable to the root induction, in which the rooting rate arrived to 100%, the root number was 7.01 and the root length was 1.38 cm on average. [Conclusion] The results wil provide some technical reference for large-scale propagation of mul-berry seedlings in vitro. 展开更多
关键词 MULBERRY Aseptic seedlings exogenous hormone Bud multiplication Root induction
下载PDF
The effect of exogenous sugar solution and high concentration of CO_2 on the contents of sugar and protein of Betula platyphylla leaves 被引量:1
6
作者 周玉梅 杨传平 +3 位作者 王淑娟 吴月亮 王文章 韩士杰 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期61-63,共3页
The content of total sugar, sucrose, fructose and protein in the leaves of3-yr.-old Betula platyphylla was measured after the treatment by three exogenous sugar solutions(sucrose, fructose, glucose) and three high con... The content of total sugar, sucrose, fructose and protein in the leaves of3-yr.-old Betula platyphylla was measured after the treatment by three exogenous sugar solutions(sucrose, fructose, glucose) and three high concentrations of CO_2 (700, 1 400, 2 100 μL/L·L^(-1))for about a month in 1998. The results showed that spraying three exogenous sugar solutionsincreased markedly the content of sugar and protein of leaves under 700 μL·L^(-1) and 1 400μL·L^(-1) CO_2 The effect of spraying exogenous sucrose solution was the best among the threeexogenous sugars. The treatment of spraying exogenous sugar solution and 2 100 μL·L^(-1) CO_2constrained the accumulation of total sugar and protein of leaves. There was no difference inprotein content of leaves when spraying glucose and fructose solutions under 700 μL·L^(-1) and 1400 μL·L^(-1) CO_2. The treatment of 2 100 μL·L^(-1) CO_2 concentration significantly increasedthe contents of total sugar, sucrose, fructose, and protein of leaves compared with that of the 700μL·L^(-1) and 1 400 μL·L^(-1) CO_2 except the plants spraying fructose solution. There waspositive correlation between the content of sugar of leaves and CO_2 concentration when sprayingsame exogenous sugar solution. 展开更多
关键词 exogenous SUGAR PROTEIN high CO_2 betula platyphylla
下载PDF
Effects of Exogenous Calcium(Ca) on the Growth of Watermelon Seedlings under NaCl Stress 被引量:2
7
作者 韩志平 张海霞 李侠 《Agricultural Science & Technology》 CAS 2017年第4期627-631,共5页
[Objective] This study was conducted to reveal the effect of exogenous calcium (Ca) in mitigating the damage caused by NaCI stress to watermelon seedlings. [Method] To the liquid medium containing 100 mmol/L NaCI, C... [Objective] This study was conducted to reveal the effect of exogenous calcium (Ca) in mitigating the damage caused by NaCI stress to watermelon seedlings. [Method] To the liquid medium containing 100 mmol/L NaCI, CaSO4 was added to the final concentrations of 4, 6, 10 and 14 mmol/L. The morphological and physiological indices including plant height, stem diameter, number of leaves per plant, maximum leaf length, maximum leaf width, seedling fresh weight and dry weight, malondialdehyde (MDA) content, relative permeability of plasma membrane, ascorbic acid (AsA) content, free proline content, soluble sugar content and soluble protein content in leaves of the seedlings treated with above media for 10 d were measured. [Result] NaCI stress significantly inhibited the growth of watermelon seedlings. The membrane permeability and MDA content in leaves were significantly increased under NaCI stress, and the contents of proline, soluble sugar, soluble protein and AsA were increased to different extents. Exogenous CaSO4 influenced the morphological and physiological indices of seedlings under NaCI stress in a manner. Treated with 6 mmol/L CaSO4, the growth of seedlings under salinity was significantly improved; membrane permeability and MDA content were drastically reduced, the contents of proline, soluble sugar, soluble pro- tein and AsA in leaves were significantly increased. [Conclusion] Exogenous CaSO+ alleviates lipid peroxidation and inhibition of seedling growth under NaCI stress by improving the abilities of antioxidation and osmotic adjustment, and 6 mmol/L CaSO4 showed the best effect. 展开更多
关键词 WATERMELON NaCI stress exogenous CaSO4 Membrane peroxidation Osmotic regulation
下载PDF
Effects of Exogenous GA_3 on Seed Germination and Seedling Growth of Salicornia europaea L. under Salt Stress 被引量:1
8
作者 李萍 华春 +5 位作者 周泉澄 周峰 陈全战 赵梦丹 李建玲 郑青松 《Agricultural Science & Technology》 CAS 2011年第2期217-221,共5页
[Objective] The paper was to study the effects of exogenous GA3 on seed germination and seedling growth of Salicornia europaea L.under salt stress.[Method] With the combination of different concentrations of NaCl(50,... [Objective] The paper was to study the effects of exogenous GA3 on seed germination and seedling growth of Salicornia europaea L.under salt stress.[Method] With the combination of different concentrations of NaCl(50,100,150,200,250,300,350,400 mmol/L)with 10 μmol /L GA3 treatments,the effects of exogenous GA3 on seed germination and seedling growth of S.europaea under salt stress were studied.[Result] Exogenous GA3 promoted the seed germination rate,germination capacity,germination index and seed vigor index of S.europaea under salt stress.Under the treatment of exogenous GA3,the root system vigor,the lengths of roots and stems and the salt-tolerance of S.europaea were higher than that of single salt stress treatment.[Conclusion] Within a certain concentration range,exogenous GA3 could alleviate the inhibition effects of salt stress on seed germination and seedling growth of S.europaea. 展开更多
关键词 Salicornia europaea L. exogenous GA3 Salt stress GERMINATION Seedling growth
下载PDF
Genetic Determination and Exogenous Influence in Sex Differentiation in Crustacean 被引量:4
9
作者 吴长功 相建海 《Developmental and Reproductive Biology》 2002年第2期137-144,共8页
The mechanisms of sex determination and the influence of exogenous factors on sex differentiation in crustacean were reviewed in the paper.Most of crustecea have not obviously sex chromosome.Androgenic gland was repor... The mechanisms of sex determination and the influence of exogenous factors on sex differentiation in crustacean were reviewed in the paper.Most of crustecea have not obviously sex chromosome.Androgenic gland was reported as the most important sex differentiation factors,implanting or cuting AG can change the sexal characterization of larval in crustacean.Although sex differentiation of crustacean is determined by gene,it is affected by exogenous factors such as parasite,photoperiod,temperature or hormone.Most cultured species have different body weight and length between male and female,this can be used in aquaculture to produce all male or female crusteceans to improve the production. 展开更多
关键词 genetic determination exogenous influence sex differentiation CRUSTACEAN
下载PDF
Review on Effects of Application of Exogenous Growth Regulating Substance on Fruits Weight of Peach
10
作者 马之胜 贾云云 +3 位作者 王越辉 白瑞霞 陈江玉 刘志欣 《Agricultural Science & Technology》 CAS 2015年第8期1681-1685,共5页
The effects of exogenous growth regulating substance on the fruit weight of peach were reviewed. Paclobutrazol could increase the single fruit weight in dif- ferent degree, and cytokinins could also increase the singl... The effects of exogenous growth regulating substance on the fruit weight of peach were reviewed. Paclobutrazol could increase the single fruit weight in dif- ferent degree, and cytokinins could also increase the single fruit weight. GA3 and B9 had no effect on fruit size or on reducing single fruit weight. Chlorflurenol-methy, ABT and salicylic acid had no effect on fruit size. Suggestions on the future re- search were put forward. 展开更多
关键词 PEACH Fruit size Yield exogenous growth regulating substance
下载PDF
Effects of Exogenous Amylases and Metal Ions on the Amylase Specific Activities and Starch Degradation of the Upper Leaves of ‘KRK_(26)' during Flue-curing 被引量:1
11
作者 赵昶灵 崔国民 孟凡来 《Agricultural Science & Technology》 CAS 2014年第10期1676-1683,共8页
Objective] The aim of this study was to investigate the effects of exoge-nous amylases and Ca2+, Mn2+ and K+ on the amylase specific activities and starch degradation of the upper leaves of 'KRK26' planted in Yun... Objective] The aim of this study was to investigate the effects of exoge-nous amylases and Ca2+, Mn2+ and K+ on the amylase specific activities and starch degradation of the upper leaves of 'KRK26' planted in Yunnan Province during flue-curing. [Method] The amylase specific activities and starch degradation of the leaves were determined by using spectrophotometry. [Result] The 8 U/g exogenous α-amy-lase could improve the specific activity of the leaf α-amylase at yel owing and color-fixing stages, but could not at stem-drying stage, and similarly, the 80 U/g exoge-nous β-amylase could improved the specific activity of the leaf β-amylase at the yel owing stage and the early period of color-fixing stage. The leaf starch could be enhanced to degrade by the exogenous α- or β-amylases and the enhancing effect of the former was stronger than that of the later. 1.50 mg/ml Ca2+ improved the specific activity of the leaf (α+β)-amylase mainly due to its enhancing effect on the leaf α-amylase, and increased the starch degradation. 4 mmol/L Mn2+ inhibited the leaf α-amylase from yel owing to the early period of color-fixing and the β- and (α+β)-amylases from the yel owing to the later period of color-fixing, but enhanced the leafα-amylase from the later period of color-fixing to the later period of stem-drying and the β- and (α+β)-amylases at the later period of stem-drying. Meanwhile, Mn2+ ham-pered the starch degradation during yel owing, but promoted it from the early period of color-fixing to stem-drying. 1 mg/ml K+ enhanced the leaf α-, β- and (α+β)-amy-lases during the yel owing stage, but lowered them from the early period of color-fix-ing to the later period of stem-drying, and always inhibited the leaf starch degrada-tion. [Conclusion] The exogenous α-, β- amylases and Ca2+ of suitable concentra-tions could be used to treat the tobacco leaves before flue-curing to improve the leaf starch degradation during the curing. 展开更多
关键词 exogenous amylases and metal ions Amylase specific activity Starchdegradation Upper leaves of flue-cured tobacco variety 'KRK26' Flue-curing
下载PDF
3D MERGE与3D SPACE STIR序列在腰椎间盘突出症检查中的应用比较 被引量:1
12
作者 李兰 殷小丹 +2 位作者 李旭雪 吴海燕 张滔 《中国医学物理学杂志》 CSCD 2024年第1期27-31,共5页
目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,... 目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,所有患者均接受常规MRI扫描及3D MERGE、3D SPACE STIR序列扫描,对比3D MERGE、3D SPACE STIR序列测量神经根直径的一致性,评价两种序列的图像质量参数[信噪比(SNR)、对比噪声比(CNR)]、图像清晰度评分。结果:3D MERGE和3D SPACE STIR序列测量的L3~S1神经根直径比较差异无统计学意义(P>0.05),且两组序列测量的L3、L4、L5和S1直径均显示出较高相关性(r=0.957,0.986,0.975,0.972,P<0.05);3D MERGE序列的SNR及CNR均高于3D SPACE STIR序列,神经根显示分级、图像清晰度评分优于3D SPACE STIR序列,差异有统计学意义(P<0.05)。结论:3D MERGE、3D SPACE STIR序列在LDH神经根直径测量中具有极高一致性,3D MERGE序列较3D SPACE STIR序列能够更清晰显示神经跟的解剖形态,图像质量更好。 展开更多
关键词 腰椎间盘突出症 3D MERGE 3D space STIR 神经根直径 图像质量
下载PDF
我国研究生学术素养研究热点分析(2013—2023年)——基于Cite Space的可视化分析研究
13
作者 高艳丽 段雨林 《西部学刊》 2024年第21期116-121,共6页
从中国知网数据库检索2013—2023年底国内发表的研究生学术素养研究相关文献,共筛选出259篇相关文献。将文献纳入Cite Space中,分别对作者、机构、关键词等进行可视化分析,并通过Excel绘制年发文量折线图,发现年发文量总体呈现下降趋势... 从中国知网数据库检索2013—2023年底国内发表的研究生学术素养研究相关文献,共筛选出259篇相关文献。将文献纳入Cite Space中,分别对作者、机构、关键词等进行可视化分析,并通过Excel绘制年发文量折线图,发现年发文量总体呈现下降趋势。发文作者为教育学领域的居多,发文机构大部分来自于各学校研究所等。高频关键词有研究生、学术道德、学术不端、学术规范、学术素养,并形成了“研究生”“学术道德”“学术不端”“治理”“学术规范”“学术素养”“博士生”“道德理论”“中心和导向”9个聚类。研究者近年来对学术素养相关研究整体呈现下降状态;研究机构以及研究人员结构单一,国家机构对学术素养相关研究较少;但关于“研究生”“学术道德”“学术不端”以及“学术理论”的研究仍有较高热度。 展开更多
关键词 学术素养 研究生 Cite space 可视化分析 研究热点
下载PDF
国内“大思政课”研究的现状、热点与展望--基于CiteSpace的核心期刊论文可视化分析
14
作者 顾晓英 周孙卿 《思想政治课研究》 2024年第3期101-114,共14页
“大思政课”是近年的一个新议题。自习近平总书记作出关于“大思政课”的重要论述以来,“大思政课”建设在全国积极推进,成为新时代用党的创新理论铸魂育人的重要抓手。学界对这一领域的研究成果持续涌现。借助Cite Space文献计量软件... “大思政课”是近年的一个新议题。自习近平总书记作出关于“大思政课”的重要论述以来,“大思政课”建设在全国积极推进,成为新时代用党的创新理论铸魂育人的重要抓手。学界对这一领域的研究成果持续涌现。借助Cite Space文献计量软件对中国知网CNKI数据库中2021-2023年间350篇核心期刊论文的发文量、作者、机构、关键词进行可视化分析,近三年学界的研究热点聚焦“大思政课”的本体论、认识论、价值论、方法论以及一体化等方面。未来,学界还应以多学科交叉和多主体融合实现“大思政课”研究的系统化,以理论和实践结合提升“大思政课”研究的科学化,以破解技术遮蔽与AI赋能强化“大思政课”研究的数字化,以研究反哺教学,不断增强“大思政课”立德树人实效。 展开更多
关键词 大思政课 Cite space 思政课教学
下载PDF
Arbuscular mycorrhizal fungi combined with exogenous calcium improves the growth of peanut(Arachis hypogaea L.)seedlings under continuous cropping 被引量:10
15
作者 CUI Li GUO Feng +6 位作者 ZHANG Jia-lei YANG Sha MENG Jing-jing GENG Yun WANG Quan LI Xin-guo WAN Shu-bo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第2期407-416,共10页
The growth and yield of peanut are negatively affected by continuous cropping.Arbuscular mycorrhizal fungi(AMF)and calcium ions(Ca^(2+))have been used to improve stress resistance in other plants,but little is known a... The growth and yield of peanut are negatively affected by continuous cropping.Arbuscular mycorrhizal fungi(AMF)and calcium ions(Ca^(2+))have been used to improve stress resistance in other plants,but little is known about their roles in peanut seedling growth under continuous cropping.This study investigated the possible roles of the AMF Glomus mosseae combined with exogenous Ca^(2+)in improving the physiological responses of peanut seedlings under continuous cropping.G.mosseae combined with exogenous Ca^(2+)can enhance plant biomass,Ca^(2+)level,and total chlorophyll content.Under exogenous Ca^(2+)application,the F_v/F_m in arbuscular mycorrhizal(AM)plant leaves was higher than that in the control plants when they were exposed to high irradiance levels.The peroxidase,superoxide dismutase,and catalase activities in AM plant leaves also reached their maximums,and accordingly,the malondialdehyde content was the lowest compared to other treatments.Additionally,root activity,and content of total phenolics and flavonoids were significantly increased in AM plant roots treated by Ca^(2+)compared to either G.mosseae inoculation or Ca^(2+)treatment alone.Transcription levels of AhCaM,AhCDPK,AhRAM1,and AhRAM2 were significantly improved in AM plant roots under exogenous Ca^(2+)treatment.This implied that exogenous Ca^(2+)might be involved in the regulation of G.mosseae colonization of peanut plants,and in turn,AM symbiosis might activate the Ca^(2+)signal transduction pathway.The combination of AMF and Ca^(2+)benefitted plant growth and development under continuous cropping,suggesting that it is a promising method to cope with the stress caused by continuous cropping. 展开更多
关键词 ARACHIS HYPOGAEA L. ARBUSCULAR MYCORRHIZAL fungi continuous CROPPING exogenous calcium
下载PDF
Intake of Volatile N-nitrosamines and Their Ability to Exogenously Synthesize in the Diet of Inhabitants from High-risk Area of Esophageal Cancer in Southern China 被引量:7
16
作者 LINKUN SHENZHONG-YING 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第4期277-282,共6页
Objective Nan'ao County in Guandong Province is a high-risk area of esophageal cancer in Southern China. Of the suspected etiological factors in the environment, N-nitrosamines and their precursors have received t... Objective Nan'ao County in Guandong Province is a high-risk area of esophageal cancer in Southern China. Of the suspected etiological factors in the environment, N-nitrosamines and their precursors have received the greatest attention. Methods Sixty samples of the diet ingested by the inhabitants were collected and detected for volatile N-nitrosamines and their precursors. Five N-nitrosamines detected by Gas Chromatography-Thermal Energy Analyzer were N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosopyrrolidine, N-nitrosopiperidine and N-nitrosomethyl-benzylamine. Results The average content of 5 volatile N-nitrosamines in the diet was 312.0 μg/kg (median). The daily intake of the nitrosamines was 286.5 μg/head/day. Only the ability to exogenously synthesize N-nitrosopiperidine was powerful among 5 volatile N-nitrosamines. By a computerized stepwise regression analysis and curve fitting, we studied the correlation among the nitrosamines, the precursors and the major food items in the samples. Conclusion It demonstrated that a relatively high content of volatile N-nitrosamines was present in the diet collected in the area. 展开更多
关键词 Volatile nitrosamines INTAKE exogenous synthesis Esophageal cancer
下载PDF
我国农产品营销渠道研究之进展——基于Cite Space的可视化分析
17
作者 胡保玲 彭思诺 《北方经贸》 2024年第12期68-72,共5页
本研究借助Cite Space软件,选取CNKI中国学术期刊网络出版总库的期刊论文,聚焦2002-2023年间我国农产品营销渠道研究文献,结果发现:我国农产品营销渠道可分为三个阶段,即萌芽期(2002-2007)、发展上升期(2008-2016)、发展综合期(2017-202... 本研究借助Cite Space软件,选取CNKI中国学术期刊网络出版总库的期刊论文,聚焦2002-2023年间我国农产品营销渠道研究文献,结果发现:我国农产品营销渠道可分为三个阶段,即萌芽期(2002-2007)、发展上升期(2008-2016)、发展综合期(2017-2023);核心作者群尚未形成,作者间与机构间的合作囿于距离和学科限制;研究机构以中部地区居多,主要为高校的管理学院。从研究内容来看,受政策导向引领,农产品营销渠道招展对策、影响因素研究较多。在我国乡村振兴战略的指导下,农产品营销趋向全渠道发展,应重视渠道主体、渠道选择以及渠道技术方面,采用多方法、多学科融合发展。 展开更多
关键词 农产品 营销渠道 可视化分析 Cite space
下载PDF
Effects of exogenous enzymes, Lactobacillus acidophilus or their combination on feed performance response and carcass characteristics of rabbits fed sugarcane bagasse 被引量:5
18
作者 Nahla A Abdel-Aziz Mounir El-Adawy +4 位作者 Maria A Mariezcurrena-Berasain Abdelfattah Z M Salem Jaime Olivares-Pérez Ahmed E Kholif Borhami E Borhami 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第3期544-549,共6页
The aim of this study was to evaluate the effect of Lactobacillus acidophilus(LAC), exogenous enzymes of ZAD(exogenous enzyme preparation) or their combination on feed conversion, and dressing of rabbits fed diffe... The aim of this study was to evaluate the effect of Lactobacillus acidophilus(LAC), exogenous enzymes of ZAD(exogenous enzyme preparation) or their combination on feed conversion, and dressing of rabbits fed different treatments of sugarcane bagasse(SCB). Five rations were allotted randomly to five groups of New-Zealand White(NZW) rabbits(n=10) with initial live body weight of(838±42.4) g and 5 weeks of age. Rabbits were fed on diets with different sources of fiber as follows,(i) a control diet composed of 100% berseem hay and 0% SCB,(ii) 50% berseem hay and 50% untreated SCB(USCB),(iii) 50% berseem hay and 50% SCB treated with L. acidophilus(LAC),(iv) 50% berseem hay and 50% SCB treated with ZAD(ZAD), and(v) 50% berseem hay and 50% SCB treated with a combination of LAC+ZAD(LZ). Treatments of SCB with L. acidophilus, ZAD and LAC+ZAD had the highest feed conversion ratio than both USCB and control. The dressing percentage of rabbits that fed the LAC and LZ diets was higher(P〈0.05) compared with that in the other groups. Performance index(PI) for LAC group was improved(P〈0.05) compared to that for the other groups; however, PI for USCB group was the lowest(P〈0.05). It could be concluded that treating SCB with L. acidophilus, exogenous enzymes of ZAD or their combination improved feed conversion and performance with more positive effects with L. acidophilus than the other treatments. 展开更多
关键词 exogenous enzymes feed conversion Lactobacillus acidophilus RABBIT sugarcane bagasse
下载PDF
Protective effects of exogenous gangliosides on ROS-induced changes in human spermatozoa 被引量:4
19
作者 Mirjana Gavella Vaskresenija Lipovac 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第3期375-381,共7页
This article summarizes the available evidence on the efficacy of gangliosides to reduce the degree of reactive oxygen species (ROS)-mediated damage. The antioxidative efficacy of exogenous gangliosides in protectin... This article summarizes the available evidence on the efficacy of gangliosides to reduce the degree of reactive oxygen species (ROS)-mediated damage. The antioxidative efficacy of exogenous gangliosides in protecting different cells encouraged us to examine their ability to protect human spermatozoa. Gangliosides are sialic acid-containing glycosphingolipids with strong amphiphilic character due to the bulky headgroup made of several sugar rings with sialic acid residues and the double-tailed hydrophobic lipid moiety. The amphiphilicity of gangliosides allows them to exist as micelles in aqueous media when they are present at a concentration above their critical micellar concentration. The protective effect of ganglioside micelles on spermatozoa is believed to stem from their ability to scavenge free radicals and prevent their damaging effects, In our study, we particularly focused our attention on the protective effect of ganglioside micelles on DNA in human spermatozoa exposed to cryopreservation. The results indicate that ganglioside micelles can modulate the hydrophobic properties of the sperm membrane to increase tolerance to DNA fragmentation, thus protecting the DNA from cryopreservation-induced damage. Further actions of ganglioside micelles, which were documented by biochemical and biophysical studies, included (i) the modulation of superoxide anion generation by increasing the diffusion barrier for membrane events responsible for signal translocation to the interior of the cell; (ii) the inhibition of iron-catalysed hydroxyl radical formation due to the iron chelation potential of gangliosides; and (iii) inhibition of hydrogen peroxide diffusion across the sperm membrane. 展开更多
关键词 exogenous gangliosides oxidative stress PROTECTION SPERMATOZOA
下载PDF
Finite-time control of linear parameter-varying systems with norm-bounded exogenous disturbance 被引量:5
20
作者 Yanjun SHEN 《控制理论与应用(英文版)》 EI 2008年第2期184-188,共5页
In this paper, a new approach is presented for finite-time control problems for linear systems subject to time-varying parametric uncertainties and exogenous disturbance. The disturbance is assumed to be time varying ... In this paper, a new approach is presented for finite-time control problems for linear systems subject to time-varying parametric uncertainties and exogenous disturbance. The disturbance is assumed to be time varying and bounded. Sufficient conditions are obtained for the existence of a linear parameter-dependent state feedback gain, which can ensure that the closed-loop system is finite-time bounded (FTB). The conditions can be reduced to feasibility problems involving LMIs. Numerical examples show the validity of the proposed methodology. 展开更多
关键词 Finite time stability Polytopic system LMI Norm-bounded exogenous disturbance
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部