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匹维溴铵联合乳果糖在肠道准备中的应用
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作者 蔡骊骊 郭传勇 +2 位作者 钱静蓉 杜明珠 黄蔚 《中国中西医结合消化杂志》 CAS 2020年第1期23-27,共5页
[目的]探究匹维溴铵联合乳果糖在肠道准备中的应用效果。[方法]选取2017年11月~2019年4月在上海市普陀区利群医院行结直肠镜检查患者90例,随机分为3组:乳果糖组、匹维溴铵组和联合组(乳果糖+匹维溴铵),对比3组检查耐受度、腹痛程度、肠... [目的]探究匹维溴铵联合乳果糖在肠道准备中的应用效果。[方法]选取2017年11月~2019年4月在上海市普陀区利群医院行结直肠镜检查患者90例,随机分为3组:乳果糖组、匹维溴铵组和联合组(乳果糖+匹维溴铵),对比3组检查耐受度、腹痛程度、肠道清洁度、炎症反应指标及不良反应情况。[结果]联合组患者检查耐受度显著高于乳果糖组与匹维溴铵组(P<0.05);联合组患者肠道清洁符合率显著高于乳果糖组与匹维溴铵组(P<0.05);联合组NRS疼痛评分、检查时间与肠鸣音恢复时间均显著低于乳果糖组与匹维溴铵组(P<0.05);检查后联合组患者心率低于乳果糖组与匹维溴铵组(P<0.05),检查后3组患者血压比较差异无统计学意义;3组患者总不良反应发生率比较差异无统计学意义。[结论]匹维溴铵联合乳果糖用于肠道准备,能够提高患者检查耐受度与肠道清洁度,减轻腹痛,且不良反应较少,可有效缩短检查时间。 展开更多
关键词 匹维溴铵 乳果糖 肠道准备 结肠镜技术 耐受度 腹痛 肠道清洁度
提高小学数学学困生成绩点滴谈 预览
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作者 魏敦姬 《教育教学论坛》 2020年第3期315-316,共2页
通过“心与心的交流和方法与方式的优化”两个方面来阐述如何轻松、愉快、有效、合理地提高小学数学学困生的教学质量。
关键词 学困生 交流 方法方式 优化 尊重 宽容 比较 改编 操作 牵手
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清香风味导向的酿酒酵母Y2的分离鉴定及生物学特性研究 预览
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作者 贾丽艳 田宇敏 +3 位作者 荆旭 韩英 王愈 杜小威 《中国食品学报》 EI CAS CSCD 北大核心 2020年第1期230-236,共7页
通过嗅觉和气相色谱分析,分离筛选得到一株高产乙酸乙酯的酵母菌株Y2。该酵母菌株在发酵液中28℃培养7 d,产乙酸乙酯量可达653 mg/L,酒精度达10.5%。通过菌落菌体形态观察、生理生化试验、26S rDNA D1/D2区域序列测序和genbank序列比对... 通过嗅觉和气相色谱分析,分离筛选得到一株高产乙酸乙酯的酵母菌株Y2。该酵母菌株在发酵液中28℃培养7 d,产乙酸乙酯量可达653 mg/L,酒精度达10.5%。通过菌落菌体形态观察、生理生化试验、26S rDNA D1/D2区域序列测序和genbank序列比对,初步确定菌株Y2为酿酒酵母。该菌株对发酵环境的耐受性较强,最高耐受温度39℃,pH 2.0,酒精度14%,糖度18%,是实际生产中理想的产香酿酒酵母。利用该菌株发酵的白酒具有清香、糟香、酯香,带酱感,落口酸爽、醇厚、绵柔,乙酸乙酯香突出,可用作清香白酒调香酒。 展开更多
关键词 清香风味 酿酒酵母 乙酸乙酯 耐受性 白酒
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Overexpression of BnKCS1-1, BnKCS1-2, and BnCER1- 2 promotes cuticular wax production and increases drought tolerance in Brassica napus 预览
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作者 Yanmei Wang Shurong Jin +5 位作者 Yi Xu Shuai Li Shuangjuan Zhang Zheng Yuan Jiana Li Yu Ni 《作物学报:英文版》 CAS CSCD 2020年第1期26-37,共12页
Higher amounts of cuticular wax in plants have been associated with improved plant stress tolerance and increased potential for industrial use.In this study,orthologs of KCS1 and CER1 in Arabidopsis,designated BnKCS1-... Higher amounts of cuticular wax in plants have been associated with improved plant stress tolerance and increased potential for industrial use.In this study,orthologs of KCS1 and CER1 in Arabidopsis,designated BnKCS1-1,BnKCS1-2,and BnCER1-2,were isolated from Brassica napus.Transcription of BnKCS1-1 and BnKCS1-2 in B.napus were induced by abscisic acid(ABA)and drought treatment,while transcription of BnCER1-2 was induced only by drought treatment.All three gene transcripts decreased significantly when plants were treated with methyl jasmonate(MeJA)or subjected to cold stress.Overexpression of BnKCS1-1,BnKCS1-2,and BnCER1-2 under the control of the CaMV35S promoter led to a significant increase in cuticular wax on transgenic B.napus leaves.BnKCS1-1 and BnKCS1-2 overexpression led to similar differences from non-transformed plants,with significantly higher levels of aldehydes(C29 and C30),alkanes(C28,C29,and C31)and secondary alcohols(C28 and C29),and a significantly lower level of C29 ketone.Overexpression of BnCER1-2 led to an increase in alkanes(C27,C28,C29,and C31),a decrease in secondary alcohols(C28 and C29),and insignificant changes in other wax components.Scanning electron microscopy revealed that overexpression of BnKCS1-1,BnKCS1-2,and BnCER1-2 in B.napus resulted in a higher density of wax crystals on the leaf surface than observed in non-transformed plants.Transgenic plants showed a reduced rate of water loss and increased drought tolerance compared to non-transformed plants.These results suggest that BnKCS1-1,BnKCS1-2,and BnCER1-2 gene products can modify the cuticular wax of B.napus.Changing cuticular waxes using transgenic approaches is a new strategy for genetic improvement of plant drought tolerance and provides an opportunity for development of B.napus as a surface-wax crop. 展开更多
关键词 Brassica napus Cuticular wax Drought tolerance OVEREXPRESSION TRANSFORMATION
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数控机床几何精度设计指标确定方法研究
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作者 王丽娜 田文杰 +1 位作者 张大卫 高卫国 《机械工程学报》 EI CAS CSCD 北大核心 2020年第1期166-174,共9页
针对数控机床几何精度设计过程中整机精度设计指标难于合理确定的问题,提出一种基于待加工试件公差指标反演机床刀具工件间相对位姿误差允许变动范围的方法。该方法首先建立试件单一公差项与机床位姿误差之间的约束关系模型,即为满足试... 针对数控机床几何精度设计过程中整机精度设计指标难于合理确定的问题,提出一种基于待加工试件公差指标反演机床刀具工件间相对位姿误差允许变动范围的方法。该方法首先建立试件单一公差项与机床位姿误差之间的约束关系模型,即为满足试件单一公差要求,机床刀具工件间相对位姿误差需要被控制在何种范围内,然后将所有公差项对应的变动范围求交集即可得到机床位姿误差的允许变动范围,并作为整机精度设计的设计指标,用于机床零部件公差分配。推导了常用公差项对应的位姿误差变动范围的求解方法,并以机床精度检验标准中轮廓加工试件为例,阐述了所提方法的应用过程。 展开更多
关键词 数控机床 几何精度 精度设计 设计指标 公差
Eect of high temperature on the balance betweenphotosynthetic light absorption and energy utilization in 预览
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作者 MA Dongdong LI Yongfu FU Haifang 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2020年第1期186-194,共9页
Chlorella pyrenoidosa(Chlorophyceae)is widely cultured for production of health food and animal feed.In outdoors,mass cultivation of C.pyrenoidosa often suffers from high temperature.A better understanding of the effe... Chlorella pyrenoidosa(Chlorophyceae)is widely cultured for production of health food and animal feed.In outdoors,mass cultivation of C.pyrenoidosa often suffers from high temperature.A better understanding of the effects of high temperature on photosynthesis and photoprotection can help optimize the productivity ofC.pyrenoidosa cultures.In this study,we investigated effect of high temperature(35,38,or 41℃)on the balance between photosynthetic light absorption and energy utilization of C.pyrenoidosa.In contrast to 30℃,higher temperature of 35 or 38℃did not inhibit the growth of C.pyrenoidosa.Treatment in 35℃maintained the balance.Moreover,the PSI acceptor side in 38℃was over-reduced and PSII reaction centers were over-excited under strong light,which destroyed the balance and generated active oxygen species(AOS).However,the activated antioxidant enzymes might remove completely the over-production of AOS,thereby protect C.pyrenoidosa cells from photodamage.It shows that this C.pyrenoidosa strain could tolerate as high as 38℃.Furthermore,treatment in 41℃resulted in more lack of the balance than that in 38℃.However,the activities of antioxidant enzymes stopped increasing in 41℃,and were not strong enough to remove the excess AOS.Therefore,treatment in 41℃could decrease the growth ofC.pyrenoidosa.In addition,strong and longtime light exposure would cause serious photodamage to C.pyrenoidosa cells. 展开更多
关键词 ANTIOXIDANT ENZYME CALVIN cycle high temperature tolerance PHOTOPROTECTION PHOTOSYNTHESIS CHLORELLA pyrenoidosa
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Adrenomedullin:an important participant in neurological diseases 预览
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作者 Feng-Jiao Li Si-Ru Zheng Dong-Mei Wang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第7期1199-1207,共9页
Adrenomedullin,a peptide with multiple physiological functions in nervous system injury and disease,has aroused the interest of researchers.This review summarizes the role of adrenomedullin in neuropathological disord... Adrenomedullin,a peptide with multiple physiological functions in nervous system injury and disease,has aroused the interest of researchers.This review summarizes the role of adrenomedullin in neuropathological disorders,including pathological pain,brain injury and nerve regeneration,and their treatment.As a newly characterized pronociceptive mediator,adrenomedullin has been shown to act as an upstream factor in the transmission of noxious information for various types of pathological pain including acute and chronic inflammatory pain,cancer pain,neuropathic pain induced by spinal nerve injury and diabetic neuropathy.Initiation of glia-neuron signaling networks in the peripheral and central nervous system by adrenomedullin is involved in the formation and maintenance of morphine tolerance.Adrenomedullin has been shown to exert a facilitated or neuroprotective effect against brain injury including hemorrhagic or ischemic stroke and traumatic brain injury.Additionally,adrenomedullin can serve as a regulator to promote nerve regeneration in pathological conditions.Therefore,adrenomedullin is an important participant in nervous system diseases. 展开更多
关键词 ADRENOMEDULLIN brain injury GLIA mechanism morphine tolerance neural regeneration neuroprotective effect pathological pain REGENERATION SENSITIZATION TARGET
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Assessment of Variation in Morpho-Physiological Traits and Genetic Diversity in Relation to Submergence Tolerance of Five Indigenous Lowland Rice Landraces 预览
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作者 Jijnasa BARIK Vajinder KUMAR +1 位作者 Sangram KLENKA Debabrata PANDA 《水稻科学:英文版》 CSCD 2020年第1期32-43,共12页
The present study evaluated submergence responses in 88 lowland indigenous rice(Oryza sativa L.) landraces from Koraput, India, to identify submergence-tolerant rice genotypes. In pot experiments, variations in surviv... The present study evaluated submergence responses in 88 lowland indigenous rice(Oryza sativa L.) landraces from Koraput, India, to identify submergence-tolerant rice genotypes. In pot experiments, variations in survival rate, shoot elongation, relative growth index, dry matter, chlorophyll, soluble sugar and starch contents were evaluated in two consecutive years under well-drained and completely submerged conditions. Principal component analysis showed that the first three axes contributed 96.820% of the total variation among the landraces, indicating wide variation between genotypes. Major traits such as survival rate, relative growth index, soluble sugar and starch contents appeared to be important determinants of phenotypic diversity among the landraces. Phenotypic coefficient of variance was higher than genotypic coefficient of variance for all the traits and all showed high heritability(90.38%–99.54%). Five rice landraces(Samudrabali, Basnamundi, Gadaba, Surudaka and Dokarakuji) were the most tolerant to submergence. When submerged for up to 14d, Samudrabali, Basnamundi and Godoba were notable for having greater survival rates than a standard submergence tolerant variety FR13 A, and also notable for elongating more vigorously and accumulating more biomass. These three landraces may therefore be especially useful in lowland rice growing areas that are affected by both moderate stagnant water and flash flooding. Molecular genotyping revealed that the submergence tolerance of Samudrabali, Basnamundi and Godoba is linked to the presence of one or more different Sub1 loci and it may well prove useful for breeding improved submergence tolerant rice varieties, thereby assising to improve yield stability in the rainfed lowland agro-ecosystem. 展开更多
关键词 genetic variability GENOTYPING indigenous rice submergence tolerance Sub1 gene
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Morpho-Physiological Response of Oryza glaberrima to Gradual Soil Drying 预览
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作者 Kartika KARTIKA Jun-Ichi SAKAGAMI +6 位作者 Benyamin LAKITAN Shin YABUTA Andi WIJAYA Sabaruddin KADIR Laily Ilman WIDURI Erna SIAGA Yoshihiro NAKAO 《水稻科学:英文版》 CSCD 2020年第1期67-74,共8页
Soil drought occurrence during dry season has been the main constraint, besides prolonged flooding during rainy season, in increasing cropping intensity and rice productivity in tropical riparian wetland. Use of droug... Soil drought occurrence during dry season has been the main constraint, besides prolonged flooding during rainy season, in increasing cropping intensity and rice productivity in tropical riparian wetland. Use of drought tolerant rice genotype might be a suitable option for overcoming such problem. This study focused on the effects of gradual soil drying during early vegetative growth stage on morphological and physiological traits of five Oryza glaberrima genotypes, namely RAM12, RAM14, RAM59, RAM97 and RAM101, and two Oryza sativa subsp japonica genotypes, i.e. Koshihikari and Minamihatamochi. The plants were subjected to 6 d of gradual soil drying condition from 15 days after transplanting(DAT) to 20 DAT, and were allowed to recover until 22 DAT. Gradual soil drying reduced plant growth as indicated by dry mass accumulation. Drought reduced stomatal conductance and increased leaf rolling score of all the genotypes. All the genotypes showed comparable response on stomatal conductance, but O. glaberrima genotypes performed higher in leaf rolling recovery. Meanwhile, O. sativa genotypes decreased total leaf area and specific leaf area, but increased specific leaf weight in order to avoid further damages due to drought stress. Drought tolerance mechanisms in RAM101, RAM12, RAM59 and RAM14 were associated with leaf morpho-physiological responses, root traits and dry biomass accumulation. 展开更多
关键词 drought tolerance leaf rolling root trait stomatal conductance dry matter accumulation
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电镀仿真技术在机械加工公差分配中的应用 预览
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作者 刘国亮 吴昊 李军威 《新技术新工艺》 2020年第1期36-39,共4页
金属镉对于钢铁基材属于阴极保护镀层。在高温高湿的环境中,镉镀层的强耐腐性常被用于军工行业的零件的表面处理。军工行业的零件,尤其是液压系统等部位的紧固件,对尺寸精度有比较高的要求,需要高精度的电镀。传统的方法根据经验尝试各... 金属镉对于钢铁基材属于阴极保护镀层。在高温高湿的环境中,镉镀层的强耐腐性常被用于军工行业的零件的表面处理。军工行业的零件,尤其是液压系统等部位的紧固件,对尺寸精度有比较高的要求,需要高精度的电镀。传统的方法根据经验尝试各种辅助工具,并多次试镀以寻求最佳方案,这种效率非常低。介绍了以一款电镀仿真软件作为工具,在电镀镉方向进行镀层厚度分布均匀性的优化和机械加工公差分配的应用。通过仿真计算的结果,快速准确而且直观地反映了零件电镀后膜厚的分布。通过添加电流遮蔽的辅助工具,并进行多个方案的仿真计算与优化,获得了膜厚分布非常均匀一致的镀层。 展开更多
关键词 公差 仿真软件 电镀镉
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嗜酸氧化亚铁硫杆菌耐重金属离子连续转接驯化试验研究 预览
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作者 刘玉龙 李广悦 +2 位作者 胡南 李建东 丁德馨 《铀矿冶》 CAS 2020年第1期27-32,共6页
采用连续转接驯化,对某铀矿山酸性矿坑水分离纯化得到的嗜酸氧化亚铁硫杆菌(A.f)进行了耐Cu 2+、Mn 2+、Cr 3+和Pb 2+的驯化试验,考察了该菌株对这些重金属离子的耐受限值及氧化活性。试验结果表明:Cu 2+、Mn 2+、Cr 3+和Pb 2+对该菌株... 采用连续转接驯化,对某铀矿山酸性矿坑水分离纯化得到的嗜酸氧化亚铁硫杆菌(A.f)进行了耐Cu 2+、Mn 2+、Cr 3+和Pb 2+的驯化试验,考察了该菌株对这些重金属离子的耐受限值及氧化活性。试验结果表明:Cu 2+、Mn 2+、Cr 3+和Pb 2+对该菌株的生长抑制作用由大到小的排序为Cr 3+>Pb 2+>Cu 2+>Mn 2+;50%接种比例的连续转接驯化可以显著提高A.f对重金属离子的耐受限值;驯化后的A.f对Cr 3+、Pb 2+、Cu 2+和Mn 2+的耐受限值分别为2.1、3.5、34.0、45.0 g/L。 展开更多
关键词 嗜酸氧化亚铁硫杆菌 驯化 重金属 耐受性
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Radiation Tolerant Viterbi Decoders for On-Board Processing (OBP) in Satellite Communications 预览
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作者 Zhen Gao Lina Yan +3 位作者 Jinhua Zhu Ruishi Han Ullah Anees Reviriego Pedro 《中国通信:英文版》 SCIE CSCD 2020年第1期140-150,共11页
Modern satellite communication systems require on-board processing(OBP)for performance improvements,and SRAM-FPGAs are an attractive option for OBP implementation.However,SRAM-FPGAs are sensitive to radiation effects,... Modern satellite communication systems require on-board processing(OBP)for performance improvements,and SRAM-FPGAs are an attractive option for OBP implementation.However,SRAM-FPGAs are sensitive to radiation effects,among which single event upsets(SEUs)are important as they can lead to data corruption and system failure.This paper studies the fault tolerance capability of a SRAM-FPGA implemented Viterbi decoder to SEUs on the user memory.Analysis and fault injection experiments are conducted to verify that over 97%of the SEUs on user memory would not lead to output errors.To achieve a better reliability,selective protection schemes are then proposed to further improve the reliability of the decoder to SEUs on user memory with very small overhead.Although the results are obtained for a specific FPGA implementation,the developed reliability estimation model and the general conclusions still hold for other implementations. 展开更多
关键词 viterbi decoder on-board processing FPGA user memory fault tolerance single event upsets
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木芙蓉对土壤铅离子的耐性及转移富集特性研究 预览
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作者 黄泽梅 周强英 李凌 《西南师范大学学报:自然科学版》 CAS 北大核心 2020年第1期108-112,共5页
为了解木芙蓉对土壤铅污染的修复潜力,以木芙蓉扦插幼苗为材料,通过盆栽试验研究不同程度土壤铅污染对木芙蓉幼苗生长、生理生化指标及铅离子转移富集特性的影响.结果表明:轻度(300 mg/kg)、中度(800 mg/kg)铅污染对木芙蓉幼苗生物量的... 为了解木芙蓉对土壤铅污染的修复潜力,以木芙蓉扦插幼苗为材料,通过盆栽试验研究不同程度土壤铅污染对木芙蓉幼苗生长、生理生化指标及铅离子转移富集特性的影响.结果表明:轻度(300 mg/kg)、中度(800 mg/kg)铅污染对木芙蓉幼苗生物量的影响不显著,植株生长正常;重度(1300 mg/kg)铅污染对木芙蓉光合系统、抗氧化系统造成严重伤害,显著抑制了木芙蓉幼苗根长、根粗和生物量的增长.随着铅污染质量分数升高,幼苗根系铅含量显著上升,在重度铅污染时达到最大值,为1610.106 mg/kg;地上地下部转移率在中度铅污染时达到最大值,为0.093;地下部富集系数在重度铅污染下大于1,与对照差异明显.说明木芙蓉根系对铅离子有较强富集能力,向茎叶转移较少,可作为修复轻度、中度铅污染的树种之一. 展开更多
关键词 木芙蓉 铅污染 耐受性 转移富集
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基于T-Map的飞机部件交点轴线公差转化方法 预览
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作者 肖欢 朱永国 +1 位作者 刘春锋 周结华 《中国机械工程》 CAS CSCD 北大核心 2019年第13期1558-1567,共10页
针对装配过程装配方案改变后,基准变换致使几何公差变化的问题,以飞机部件装配中的交点装配为研究对象,提出基于公差图(T-Map)的公差转化方法。根据交点轴线的变动建立交点轴线的T-Map公差模型;通过基准变换前后几何尺寸及公差(GD&T... 针对装配过程装配方案改变后,基准变换致使几何公差变化的问题,以飞机部件装配中的交点装配为研究对象,提出基于公差图(T-Map)的公差转化方法。根据交点轴线的变动建立交点轴线的T-Map公差模型;通过基准变换前后几何尺寸及公差(GD&T)关系构建交点轴线的基准变换模型,在此基础上,重构基准变换后交点轴线的T-Map;对变换后的交点轴线T-Map进行累积,构建交点轴线叠加T-Map(ST-Map),分析基准变换前T-Map与ST-Map的二维空间域的关系,得到ST-Map最小约束条件,并以不同自由度约束下的最大公差值为判据,获得基于T-Map的交点轴线公差转化关系。最后,引入实例进行公差转化的求解,并与基于特征公差尺寸链的传统公差转化方法进行了比较。 展开更多
关键词 飞机 装配 公差 基准 公差图
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Drought Tolerance Identification and Eevluation of Maize during Flowering Stage in Guangxi 预览
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作者 Chenglin ZOU Hua TAN +5 位作者 Debo ZHENG Ruining ZHAI Aihua HUANG Runxiu MO Xinxing WEI Kaijian HUANG 《亚洲农业研究:英文版》 2019年第6期77-84,共8页
Total 20 maize varieties were subjected to drought stress at flowering stage,and then the relative water content,soluble sugar content,chlorophyll content,malondialdehyde( MDA) content and superoxide dismutase( SOD) a... Total 20 maize varieties were subjected to drought stress at flowering stage,and then the relative water content,soluble sugar content,chlorophyll content,malondialdehyde( MDA) content and superoxide dismutase( SOD) activity in their leaves,as well as their yields were determined. The drought tolerance of the physiological and biochemical indexes was scored by five-level scoring method,and the drought tolerance index was calculated by the yield index to comprehensively evaluate the drought tolerance of maize during flowering stage. The results showed that the scores of drought tolerance of the maize varieties ranged from 1. 929 3 to 5. 659 5. Among them,the scores of Zhengda 619,Guidan 162 and Guidan 0810 were greater than 5. 0,followed by Dika 008,Xianyu 30 T60,Xianzhengda 901,Qingnong 68,South America No. 1 and Wanchuan 1306 of which the scores were in the range of 4. 0-5. 0. The drought tolerance indexes were in the range of 0. 410 4-1. 096 3. Among the test maize varieties,the drought tolerance indexes of Guidan 0810,Pacific 99 and Zhengda 619 were greater than 1. 0,and those of Xianyu 30 T60,Dika 008 and South America No. 1 were in the range of 0. 9-1. 0. The correlation between the two kinds of evaluation results was 0. 588 7 and was extremely significant. The five-level scoring method and the drought tolerance index can be used simultaneously for the evaluation of drought tolerance of maize during flowering stage. The two aspects of evaluation results showed that Guidan 0810,Zhengda 619,Xianyu 30 T60,Dika 008 and South America No. 1 were drought-tolerant varieties,among which Guidan 0810 and Zhengda 619 were extremely highly drought-tolerant varieties. 展开更多
关键词 MAIZE DROUGHT TOLERANCE identification DROUGHT TOLERANCE index DROUGHT stress FLOWERING STAGE
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Control of Common Chickweed in Winter Wheat with Postemergence Herbicides 预览
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作者 Nader Soltani Christy Shropshire Peter H. Sikkema 《美国植物学期刊(英文)》 2019年第11期2012-2019,共8页
A total of six experiments were conducted over a two-year period (2018, 2019) at the University of Guelph Ridgetown Campus to assess the efficacy of various herbicides applied postemergence (POST) for the control of c... A total of six experiments were conducted over a two-year period (2018, 2019) at the University of Guelph Ridgetown Campus to assess the efficacy of various herbicides applied postemergence (POST) for the control of common chickweed in winter wheat. Fluroxypyr/bromoxynil/MCPA, pyrasulfotole/bromoxynil,pyrasulfotole/bromoxynil/fluroxypyr,pyrasulfotole/bromoxynil/thiencarbazone, pyrasulfotole/bromoxynil/thiencarbazone + MCPA ester, tolpyralate and fluroxypyr/halauxifen + MCPA EHE, applied POST, controlled common chickweed only 5% - 42% at 2 weeks after treatment (WAT) and 1% - 23% at 4 WAT and resulted in common chickweed density and biomass that was similar to non-treated weedy control. Fluroxypyr/halauxifen + pyroxsulam + MCPA EHE, applied POST, provided 57% - 82% control of common chickweed and reduced density 93% and biomass 98% compared to the non-treated control. Thifensulfuron/tribenuron, thifensulfuron/tribenuron + MCPA ester, thifensulfuron/tribenuron + fluroxypyr + MCPA ester, tribenuron + thiencarbazone, and tribenuron + thiencarbazone + MCPA ester, applied POST, controlled common chickweed 98% - 100% and reduced common chickweed density 96% - 98% and common chickweed biomass 99%. Based on these results, herbicide treatments which contained tribenuron including thifensulfuron/tribenuron, thifensulfuron/tribenuron + MCPA ester, thifensulfuron/tribenuron + fluroxypyr + MCPA ester, tribenuron + thiencarbazone, and tribenuron + thiencarbazone + MCPA ester were the most efficacious for the control of common chickweed in wheat. In addition, fluroxypyr/halauxifen + pyroxsulam + MCPA EHE, applied POST, can provide adequate control of common chickweed in winter wheat. 展开更多
关键词 WINTER Wheat WEED CONTROL NO-TILLAGE Biomass Density Injury TOLERANCE Yield
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耐草甘膦杂草的研究现状 预览
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作者 贾芳 崔海兰 +1 位作者 李香菊 于惠林 《杂草学报》 2019年第1期1-9,共9页
草甘膦是目前世界上用量最大、应用范围最广的农药,因为在转基因抗草甘膦作物田中过度依赖其除草,耐草甘膦杂草将演替成优势种群。耐受性杂草不但增加了杂草防除难度和成本,而且还会导致在农田生态系统中因过量使用草甘膦而出现一系列... 草甘膦是目前世界上用量最大、应用范围最广的农药,因为在转基因抗草甘膦作物田中过度依赖其除草,耐草甘膦杂草将演替成优势种群。耐受性杂草不但增加了杂草防除难度和成本,而且还会导致在农田生态系统中因过量使用草甘膦而出现一系列生态风险问题。本文通过对草甘膦特性、耐草甘膦杂草现状和耐受机制等进行较系统的总结和分析,以期为我国未来抗除草剂作物商业化种植后制定杂草治理策略奠定基础,也为草甘膦在转基因作物田高效安全地使用提供理论依据。 展开更多
关键词 草甘膦 耐受性 杂草 耐受机制 研究现状 展望
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Effects of Moisture Deficit on the Yield of Cowpea Genotypes in the Guinea Savannah of Northern Ghana 预览
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作者 Damba Yahaya Nicholas Denwar Matthew W. Blair 《农业科学(英文)》 2019年第4期577-595,共19页
Cowpea is multipurpose, leguminous, high protein crop in the tropics that provides food for humans and fodder for animals. The crop adds nitrogen and other nutrients to the soil through symbiotic relationship with rhi... Cowpea is multipurpose, leguminous, high protein crop in the tropics that provides food for humans and fodder for animals. The crop adds nitrogen and other nutrients to the soil through symbiotic relationship with rhizobia and direct decomposition of cowpea by-products. Despite its multiple benefits for humankind, the yield of cowpea is far below its potential and its production in the crop’s birthplace of Africa is especially affected by abiotic factors. Soil moisture deficit is one of the main abiotic factors that affect the yield of cowpea in the semi-arid tropics, including the Sahelian and Guinea Savannah regions in West Africa. Even though cowpea is a drought tolerant legume, different genotypes respond differently to drought, resulting in up to 100% or more yield increases in the case of resistant genotypes or 50% or more yield loss in case of susceptible types. Mitigating the effect of soil moisture deficit on cowpea production requires selection of genotypes that can withstand drought. With this in mind, the goal of this study was to identify drought tolerant cowpea germplasm for the Savannah region of Northern Ghana using cultivated genotypes from the United States Department of Agriculture (USDA) tested with and without irrigation at the Bontanga irrigation facility during the dry season in 2018. Fifty genotypes were used, which included 45 imported from USDA and five (5) local genotypes from the Savannah Agriculture Research Institute (SARI). The experiment had 2 × 50 factorial treatments (irrigation × genotypes) and consisted of randomized complete block design with three (3) replications per treatment. Two (2) watering regimes were introduced namely, drought stressed (no irrigation) and non-stressed/control (irrigated). Morpho-physiological, phenological and yield data were taken on the cowpeas evaluated with drought tolerance assessed based on grain yield data and derived indices. All parameters measured showed significant differences (p ≤ 0.05) except for the number of branches per plant. Ge 展开更多
关键词 Tolerance COWPEA Stress Selection DROUGHT
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Positive Thinking Training Increases Tolerance Levels of Ambiguity and Distress in Men with Hemophilia 预览
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作者 Masoumeh Beiranvand Majid Keramati Moghadam +3 位作者 Reza Sabounchi Ghasem Asadpour Nahid Jahani Azam Ghafuori 《运动科学:英文版》 2019年第3期88-95,共8页
Background: Low levels of ambiguity tolerance and distress tolerance observed in people with hemophilia lead to decreasing their function and quality of life. How positive thinking training program affects tolerance o... Background: Low levels of ambiguity tolerance and distress tolerance observed in people with hemophilia lead to decreasing their function and quality of life. How positive thinking training program affects tolerance of ambiguity and distress is not completely understood. Accordingly, the purpose of this study was to explain the role of positive thinking training in men with hemophilia of Lorestan province and examine its effectiveness on ambiguity tolerance and distress tolerance. Method: The statistical population of this study included 129 patients with hemophilia who were a member of Hemophilia Association of Lorestan province. Thirty (30) patients who were randomly selected were randomly assigned to the experimental group (N = 15) and the control group (N = 15). The design of present study was an experimental design with the pre- and post-test that the experimental group received a positive thinking training. Eight techniques that were adapted from Seligman’s techniques were used to teach positive thinking. These techniques were held in 8-two hours sessions (two sessions per week). The instrument of this study included Simons and Gaher’s distress tolerance scale and McLean and David’s ambiguity tolerance questionnaire. The collected data were analyzed by the analysis of covariance. Results: The results of this study showed that there was a significant difference between scores of post-test and follow-up of two variables in two groups. Conclusion: The amount of ambiguity tolerance and distress tolerance increased in the experimental group in comparison with control group. 展开更多
关键词 POSITIVE thinking AMBIGUITY TOLERANCE DISTRESS TOLERANCE hemophilia.
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Predictive Factors of Intracranial Response of Immune Checkpoint Inhibitors in Patients with Brain Metastasis from Non-Small Cell Lung Cancer 预览
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作者 Julien Bermudez Celine Mascaux +5 位作者 Youssef Trigui Julie Biemar Mohamed Boucekine Laurent Greillier Fabrice Barlesi Pascale Tomasini 《癌症治疗(英文)》 2019年第8期692-707,共16页
Background: Immune checkpoint inhibitors (ICI)s were recently approved for the treatment of advanced non-small cell lung cancer (NSCLC). Whereas brain metastases (BM) are frequent in NSCLC patients, data are missing r... Background: Immune checkpoint inhibitors (ICI)s were recently approved for the treatment of advanced non-small cell lung cancer (NSCLC). Whereas brain metastases (BM) are frequent in NSCLC patients, data are missing regarding ICIs intracranial efficacy and tolerance in patients with BM from NSCLC. Methods: This retrospective study was performed in the Multidisciplinary Oncology and Therapeutic Innovation department, Marseille, France between April 2013 and February 2016. Data from patients with NSCLC with at least one BM, and treated with ICIs (anti-PD1, anti-PDL1 or anti-CTL4) were analyzed. Clinical, biological data and outcomes were retrieved from electronic patients’ records. We assessed ICIs intracranial efficacy and tolerance. Results: Data from 55 patients were analyzed. Objective Response Rate (ORR) and Disease Control Rate (DCR) were respectively of 1.8 and 36.4%. Median overall survival was 17.2 months and median progression free survival was 2.9 months. Intracranial ORR (icORR) and intracranial DCR (icDCR) were respectively 16.4% and 45.5%. Both were independent of smoking status, intracranial treatment, performance status, pathology, molecular profile and the presence or number of BM at diagnosis. However, there was a trend towards an association between icORR and ECOG PS (p = 0.05), tobacco status (p = 0.057) and intracranial treatment. Adverse events were seen in 38.2% patients without identified predictive factor. Neurological symptoms appeared in 5.5% patients during immunotherapy and improved in 3.63% patients. Conclusions: ICIs can be used safely on patients with BM from NSCLC. However, intracranial response is heterogeneous in such patients and we showed ECOG PS, tobacco smoking and intracranial treatment to be associated with an improved icORR. This is the first study looking for predictive factors of intracranial response of ICIs in patients with BM from NSCLC. 展开更多
关键词 Lung Cancer Brain METASTASIS IMMUNOTHERAPY Efficacy Tolerance
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