期刊文献+
共找到1,269篇文章
< 1 2 64 >
每页显示 20 50 100
Principal Component Analysis and Cluster Analysis of Fagopyrum tataricum Varieties(Lines) 被引量:2
1
作者 赵建栋 李秀莲 +2 位作者 史兴海 陈稳良 高伟 《Agricultural Science & Technology》 CAS 2016年第12期2707-2712,共6页
In order to reveal the genetic differences and agronomic traits of Fagopy-rum tataricum_ varieties (lines) intuitively, explore good resources and avoid the blindness of parent selection during the breeding process,... In order to reveal the genetic differences and agronomic traits of Fagopy-rum tataricum_ varieties (lines) intuitively, explore good resources and avoid the blindness of parent selection during the breeding process, six primary agronomic traits of 45 F. tataricum_ varieties (lines) that came from the eleven buckwheat breeding departments across the country were analyzed with principal component analysis and cluster analysis. The results of principal component analysis showed that the six agronomic traits could be simplified into three principal components, and the cumulative contribution rate reached 83%. The results of cluster analysis showed that the 45 F. tataricum varieties (lines) were classified into four groups:high stalk, medium yield and smal grain type, medium stalk, high yield and large grain type, medium stalk, low yield and smal grain type and high stalk, medium yield and medium grain type. Among them, performance of comprehensive trait of the second type was better than that of the other types. Thus, the F. tataricum_va-rieties (lines) that were classified into the second type could be considered as good varieties (lines) or breeding materials. The genetic differences among F. tataricum_varieties (lines) had no necessary correlations with origin and geographical distance. ln addition to complementary traits and geographical distance, genetic distances (dif-ferent populations) should be taken into consideration during parent selection in cross breeding. 展开更多
关键词 Fagopyrum tataricum Agronomic traits Cluster analysis
下载PDF
Characterization of QTL for unique agronomic traits of new-plant-type rice varieties using introgression lines of IR64 被引量:3
2
作者 Analiza G.Tagle Daisuke Fujita +5 位作者 Leodegario A.Ebron Mary Jeanie Telebanco-Yanoria Kazuhiro Sasaki Tsutomu Ishimaru Yoshimichi Fukuta Nobuya Kobayashi 《The Crop Journal》 SCIE CAS CSCD 2016年第1期12-20,共9页
To enhance the yield potential of an elite indica rice cultivar,an introgression(BC_3-derived) line of IR64,YTH288,was developed using a new-plant-type cultivar,IR66215-44-2-3,as a donor parent.YTH288 has agronomicall... To enhance the yield potential of an elite indica rice cultivar,an introgression(BC_3-derived) line of IR64,YTH288,was developed using a new-plant-type cultivar,IR66215-44-2-3,as a donor parent.YTH288 has agronomically valuable characteristics such as large panicles,few unproductive tillers,and large leaves inherited from NPT.To identify the genetic basis of these traits,we used 167 F_2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits:days to heading(DTH),culm length(CL),flag leaf length(FLL),flag leaf width(FLW),and filled spikelet number per panicle(FSN).Six putative QTL were detected:four on chromosome4(for CL,FLL,FLW,and FSN) and two on chromosome 2(for DTH and FLL).All QTL with the IR66215-44-2-3 allele,except that for FLL on chromosome 2,had positive effects on each trait.To confirm the effects of these putative QTL,we developed NILs with the IR64 genetic background by marker-assisted selection.We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4.Additionally,four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropic To enhance the yield potential of an elite indica rice cultivar, an introgression(BC3-derived) line of IR64, YTH288, was developed using a new-plant-type cultivar,IR66215-44-2-3, as a donor parent. YTH288 has agronomically valuable characteristics such as large panicles, few unproductive tillers, and large leaves inherited from NPT.To identify the genetic basis of these traits, we used 167 F2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits: days to heading(DTH), culm length(CL), flag leaf length(FLL), flag leaf width(FLW), and filled spikelet number per panicle(FSN). Six putative QTL were detected: four on chromosome4(for CL, FLL, FLW, and FSN) and two on chromosome 2(for DTH and FLL). All QTL with the IR66215-44-2-3 allele, except that for FLL on chromosome 2, had positive effects on each trait. To confirm the effects of these putative QTL, we developed NILs with the IR64 genetic background by marker-assisted selection. We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4. Additionally, four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropiceffects for unique agronomic traits. These NILs can be used as research materials for studying each trait and as breeding materials for yield improvement of indica rice cultivars. 展开更多
关键词 Agronomic traits Quantitative trait loci Near-isogenic lines New-plant-type RICE variety PLEIOTROPIC effect
下载PDF
Nutritional and Technological Characteristics of New Cowpea (<i>Vigna unguiculata</i>) Lines and Varieties Grown in Eastern Kenya 被引量:2
3
作者 Peter K. Biama Abdul K. Faraj +2 位作者 Christopher M. Mutungi Isaac N. Osuga Rose W. Kuruma 《Food and Nutrition Sciences》 2020年第5期416-430,共15页
Protein sources in the diet of people living in semi-arid land of Kenya are lacking and if available it is costly to them. In terms of safe food and a healthy food supply, cowpeas (Vigna unguiculata.) are a significan... Protein sources in the diet of people living in semi-arid land of Kenya are lacking and if available it is costly to them. In terms of safe food and a healthy food supply, cowpeas (Vigna unguiculata.) are a significant source of protein, carbohydrates, and minerals especially for poor populations in the Kenya, it is said to be poor man’s meat. The aim of this study was to determine nutritional composition of newly bred ten cowpea lines and five varieties commonly grown in Eastern Kenya of Kitui, Machakos and Makueni counties to understand their potential utilization in curbing rising food and nutrition insecurity in arid and semi-arid lands ASALs and in any other food applications in Kenya. The experiment was arranged in Completely Randomized Design (CRD) whereby proximate composition and minerals were determined using standard AOAC and AACC methods and technological characteristics checked using modified methods used by other researchers. Collected data were subjected to Analysis of Variance (ANOVA) using SAS (2006) version 9.1, mean separation was done using Tukey’s Honestly Significant Difference (HSD) method at 5% level of significance. Cowpeas composition ranged from 12.28% - 13.35% for moisture content, 49.37% - 55.74% for total carbohydrates, 2.99% - 3.34% for crude ash, 0.13% - 0.81% for crude lipids, 23.37% - 29.70% for crude protein and 1.40% - 4.34% for crude fibers. Cowpea samples recorded highest percentage of essential amino acids (60.71%) and non-essential amino acids (39.29%). Minerals ranged from 1.97 - 2.69 mg/100g for calcium, 3.23 - 3.90 mg/100g for magnesium, 205.53 - 223.30 mg/100g for sodium, 0.80 - 1.23 mg/100g for zinc, 1071.15 - 1152.62 mg/100g for potassium and 0.62 - 1.06 mg/100g for phosphorus. For technological properties, lines absorbed water equivalent to their weights and they were comparable to varieties grown in the region. From the results it showed that cowpea line IT97K-1042-3, TEXAN PINKIYE, TX123, IT85F-867-5, IT82D-889-1 and IT82D-889 have desirable attributes such as high crude protein contents, good water absorption capacities and volumetric expansion. They compared well with existing K80 variety. These cowpea lines could possibly be bred and combined into a single cowpea line and further improved by breeders to have other good properties such as higher levels of water absorption during soaking hence reduced cooking times. Therefore, this work has shown that cowpea lines developed can be used as food security crop, industrial food applications and enriching foods of low protein like in complementary foods for healthy food supply in Eastern Kenya. 展开更多
关键词 COWPEA lines varieties EASTERN Kenya NUTRITIONAL Technological Characteristics
下载PDF
Distribution and Selective Effects of Vrn-A1,Vrn-B1,and Vrn-D1 Genes in Derivative Varieties from Four Cornerstone Breeding Parents of Wheat in China 被引量:1
4
作者 ZHANG Yang LIU Wan-chen +5 位作者 LI Jun WEI Hui-ting HU Xiao-rong LI Yue-jian LU Bao-rong YANG Wu-yun 《Agricultural Sciences in China》 CAS CSCD 2010年第10期1389-1399,共11页
Vernalization, the process of a long exposure to low temperature to induce flowering in plants, is essential for plants to adapt to cold winters. The presence of vernalization genes Vrn-A1, -B1, and -D1 in four corner... Vernalization, the process of a long exposure to low temperature to induce flowering in plants, is essential for plants to adapt to cold winters. The presence of vernalization genes Vrn-A1, -B1, and -D1 in four cornerstone breeding parents of wheat in China (Funo, Mentana, Yanda 1817, and Bima 4) and 322 derivative varieties (mostly winter wheat) from these parents were determined using PCR based molecular method. The frequencies of the VRN-1 genes in these derivative varieties were in order of Vrn-Dl(67.1%)〉 Vrn-Bl(19.6%)〉 Vrn-Al(5.3%), which are similar as the former conclusion that Vrn-D1 is associated with the latest heading time, Vrn-A1 the earliest, and Vrn-B1 intermediate values. The frequencies of Vrn-Al and Vrn-B1 loci in the derivative varieties from winter wheat zones were higher than that from spring winter zones. Based on the wheat breeding history in China and the fact of non-random distribution of Vrn-A1 and Vrn-B1 in the derivative varieties from the four parents, there could be a strong selective effect on VRN-1 genes in different regions where the derivative varieties were cultivated. 展开更多
关键词 vernalization cornerstone breeding parents of wheat derivative varieties
下载PDF
Correlation of Inhibitor Proteinase in Varieties and Lines of Cotton(Gossypium hirsutum L.) to Different Geographic Population of Verticillium dathliae Klebahn
5
作者 KIM Robert AMANTURDIEV Alisher MEJLUMYAN Larisa BABAYEV Yashen KIM Michael 《棉花学报》 CSCD 北大核心 2008年第S1期108-,共1页
Breeding for wilt resistance and its theoretical basis are primarily responsible for increases in cotton yield and fiber quality. Breeding for immunity is the most efficient method in our struggle with infectious dise... Breeding for wilt resistance and its theoretical basis are primarily responsible for increases in cotton yield and fiber quality. Breeding for immunity is the most efficient method in our struggle with infectious diseases. 展开更多
关键词 ISOLATE VERTICILLIUM VIRULENCE varieties and lines degree of affection phenotype proteinase inhibitor
下载PDF
Research on the Adaptability of New Flue-cured Tobacco Varieties(Lines) in Ankang Tobacco Growing Area
6
作者 奚柏龙 党军政 +3 位作者 朱峰 赵鹏 耿伟 李淑娥 《Agricultural Science & Technology》 CAS 2014年第4期589-595,658,共8页
In order to screen new flue-cured tobacco varieties (lines) with mountain characteristics of Ankang tobacco growing area, the adaptable selection experiments of 6 newly introduced flue-cured tobacco varieties (line... In order to screen new flue-cured tobacco varieties (lines) with mountain characteristics of Ankang tobacco growing area, the adaptable selection experiments of 6 newly introduced flue-cured tobacco varieties (lines) were carried out at the 2 set test sites in Ankang producing areas with K326, 'Yunyan 87' and 'Qinyan 96' as controls. The results showed that YN105 had more leaves per plant and coordi- nate chemical composition, and the yield per unit area was 2 221.05 kg/hm2 with the single output of 33 960.00 yuan/hm^2. Its rate of high and medium class leaves was 80.17%, presenting good performances in testing varieties (lines). The flowering of YN99 was late but showed coordinate chemical composition, and the yield per unit area was 2 128.50 kg/hm^2 with the single output of 33 454.05 yuan/hm^2. Its rate of high and medium class leaves was 83.17%, which also had good perfor- mances in testing varieties (lines). It was recommended that YN105 and YN99 be moderate planted in Ankang tobacco growing area, but further experiment is needed to confirm. 展开更多
关键词 Ankang Mountain tobacco varieties lines ADAPTABILITY
下载PDF
NEW VARIETIES AND LINES
7
作者 LIU Xinhua Zhejiang Jinhua Agr Re Inst 《Chinese Rice Research Newsletter》 1995年第2期12-12,共1页
Ⅱ-you 92: a new hybrid rice for late seasonⅡ-you 92 is an indica hybrid rice that was developed by Jinhua Agri Res Inst, Zhejiang Province.Ⅱ-you 92 has a suitable growth duration of 122-125 d as double-cropping lat... Ⅱ-you 92: a new hybrid rice for late seasonⅡ-you 92 is an indica hybrid rice that was developed by Jinhua Agri Res Inst, Zhejiang Province.Ⅱ-you 92 has a suitable growth duration of 122-125 d as double-cropping late season rice, 3-4 dshorter than that of Shanyou 64 and 6-7 d shorter than Shanyou 10. It has a compact plant type, high tiller-ing ability and plant height of 85-90 cn. A number of 3.4-3.6 million effective panicles per ha can be 展开更多
关键词 THAN NEW varieties AND lines HIGH
下载PDF
NEW VARIETIES AND LINES
8
《Chinese Rice Research Newsletter》 1995年第1期12-12,共1页
Qixiuzhan 3:a new high-yielding, good-quality indica rice varietyBy crossing Qishanzhan with Xinxiu 299, a new variety Qixiuzhan 3 was developed by the Rice Res Inst ofGuangdong Acad of Agri Sci.Being planted in the e... Qixiuzhan 3:a new high-yielding, good-quality indica rice varietyBy crossing Qishanzhan with Xinxiu 299, a new variety Qixiuzhan 3 was developed by the Rice Res Inst ofGuangdong Acad of Agri Sci.Being planted in the early season, this variety belongs to mid-late-maturity rice, with the same ma- 展开更多
关键词 HIGH NEW varieties AND lines
下载PDF
Cultivar Mixture Cooperation(CMC)of rice varieties(lines) with different blast resistant gene
9
作者 Reported by Fu Xiulin et al,Jilin Acad of Agri Sci, Gongzhuling 136102, China 《Chinese Rice Research Newsletter》 1998年第1期12-12,共1页
We studied Cultivar Mixture Cooperation(CMC)of rice varieties(lines)by screening mixture ofrice varieties which possess different genes,1983-1996.
关键词 CMC)of rice varieties with different blast resistant gene Cultivar Mixture Cooperation lines gene
下载PDF
Evaluation and screening for resistance of some varieties(lines)to major diseases and insect pests of rice
10
作者 SHEN Ying HU Guowen CNRRL Hangzhou 310006,China 《Chinese Rice Research Newsletter》 1991年第2期3-3,共1页
During 1984-1988,2,231 varieties(lines)from International Rice Testing Program(IRTP)were evaluated and screened for resistance to riceblast(Bl),bacterial blight(BB),sheath blight
关键词 Evaluation and screening for resistance of some varieties lines)to major diseases and insect pests of rice
全文增补中
Lodging Resistance of Aromatic CMS Line Zhongzhe A and Its Derived Lines 被引量:1
11
作者 Peng Zhang Kunjun Ouyang +4 位作者 Zhengzheng Zhong Yu Gao Zhihua Tong Shuirong Sun Hanhua Tong 《American Journal of Plant Sciences》 2019年第3期351-368,共18页
Nineteen rice combinations derived from Zhongzhe A and its derived lines, as well as Y Liangyou 1 as the control, were used to study lodging resistance by detecting plant height and some of the traits of culm and pani... Nineteen rice combinations derived from Zhongzhe A and its derived lines, as well as Y Liangyou 1 as the control, were used to study lodging resistance by detecting plant height and some of the traits of culm and panicle that are related to lodging. The results indicated that the lodging resistance of 16 combinations was significantly stronger than that of Y Liangyou 1. Moreover, the lodging resistances of all combinations derived from Zhongzhe 2A, Zhongzhe 3A, Huazhe A and Zhong 1A were significantly higher than that of Y Liangyou 1. Additionally, the traits related to lodging were not identical within different CMS rice lines, and the relationship between plant height and lodging resistance was only significantly (P < 0.01) detected in Zhongzhe 2A. Some traits of the second internode were closely related to lodging in all combinations, which can be used as an effective index in lodging resistance breeding in rice. 展开更多
关键词 CYTOPLASMIC MALE STERILE Line Derived lines LODGING Resistance Rice
下载PDF
DIRECTIONAL DERIVATIVE OF VECTOR FIELD AND REGULAR CURVES ON TIME SCALES
12
作者 Emin zyilmaz 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第10期1349-1360,共12页
The general idea in this paper is to study curves of the parametric equations where the parameter varies in a so-called time scale, which may be an arbitrary closed subset of the set of all real numbers. We introduce ... The general idea in this paper is to study curves of the parametric equations where the parameter varies in a so-called time scale, which may be an arbitrary closed subset of the set of all real numbers. We introduce the directional derivative according to the vector fields. 展开更多
关键词 time scale nabla derivative regular curve tangent line vector field
下载PDF
Learning to Support Derivation of Adaptable Products in Software Product Lines
13
作者 Anissa Benlarabi Amal Khtira Bouchra El Asri 《Journal of Computer and Communications》 2020年第4期114-126,共13页
Software product line engineering is a large scale development paradigm based on mass production. It consists in building a common platform from which a set of products can be derived. Under the constraints of continu... Software product line engineering is a large scale development paradigm based on mass production. It consists in building a common platform from which a set of products can be derived. Under the constraints of continuous evolution and costs optimization, the derivation process must be able to answer customers’ requirements and provide adequate products in a short time without defects. However, this purpose cannot be achieved if the customer must wait for the change is implemented in the common platform. In this paper, we describe our work which proposes a framework to manage derivation of adaptable products. An adaptable product is obtained by deriving the most similar product from the common platform and changing it to support the new requirements. The aim of the framework is to give quick response to the customers need while the new requirements are being implemented in the common platform. The framework includes tools for processing natural language requirements, computing the similarity between products on the basis of their requirements, and the product adaptation effort measuring. 展开更多
关键词 Software PRODUCT lines REQUIREMENT SIMILARITY PRODUCT DERIVATION Natural Language Processing SEMANTIC Models
下载PDF
基于主成分和聚类分析7个深绿线椒品种的商品品质和产量评价
14
作者 黄冬福 杨娅 +5 位作者 范高领 付文婷 涂祥敏 吴迪 詹永发 何建文 《贵州农业科学》 CAS 2024年第2期15-21,共7页
【目的】探明深绿线椒品种的商品品质和产量差异,为贵州辣椒产业品种结构调整和优势区域布局提供科学依据。【方法】以7个深绿线椒品种(长辣七号、湘辣17号、卓椒七号、卓椒八号、香辣八号、红冠303、泰丰五号)为研究对象,采用SPSS 26.... 【目的】探明深绿线椒品种的商品品质和产量差异,为贵州辣椒产业品种结构调整和优势区域布局提供科学依据。【方法】以7个深绿线椒品种(长辣七号、湘辣17号、卓椒七号、卓椒八号、香辣八号、红冠303、泰丰五号)为研究对象,采用SPSS 26.0进行变异系数分析和主成分分析,Origin 2022进行相关性和聚类分析,对其商品品质与产量进行综合评价。【结果】7个深绿线椒品种的商品品质及产量性状变异系数为6.91%~28.17%,其中,以果形指数变异系数最小,单果鲜重的变异系数最大;单果鲜重与果纵径、鲜椒产量与干物质含量分别呈极显著相关性,果纵径与果横径、单果鲜重与果横径、干椒产量与单株挂果数、单株挂果数与果纵径、单株挂果数与单果鲜重、单果鲜重与干物质含量分别呈显著相关性。基于深绿线椒品种的9个性状,通过主成分分析建立综合表现评价模型,得出品种卓椒七号的综合表现最佳,其产量最高,达2410 kg/667m^(2)。聚类分析将7个线椒品种分为适合鲜加工(长辣七号、红冠303、香辣八号和湘辣17号)、既适合鲜加工又适合干加工(泰丰五号和卓椒八号)及适合绿熟期采收上市(卓椒七号)3类。【结论】7个深绿线椒品种的多样性丰富,单果鲜重、果横径、果纵径、单株挂果数是构成鲜椒产量的主要因素,单株挂果数是构成干椒产量的主要因素;卓椒七号鲜椒产量最高,适合在绿熟期采收上市;卓椒八号果形和果肉厚适中,鲜椒和干椒产量中上,是理想的加工型辣椒品种。 展开更多
关键词 辣椒 深绿线椒品种 商品品质 品种评价 品质 产量
下载PDF
头颈部恶性肿瘤研究模型的演化 被引量:1
15
作者 王安训 周万航 曹琮沅 《口腔疾病防治》 2024年第9期653-663,共11页
恶性肿瘤发生发展的机制探索以及抗癌药物治疗疗效的评估均有赖于各种体内与体外研究模型的建立。近几十年间,随着生物医学技术的快速发展,恶性肿瘤的体内外研究模型也发生了巨大的变化。基因检测技术从单基因到多基因的进展促进了生物... 恶性肿瘤发生发展的机制探索以及抗癌药物治疗疗效的评估均有赖于各种体内与体外研究模型的建立。近几十年间,随着生物医学技术的快速发展,恶性肿瘤的体内外研究模型也发生了巨大的变化。基因检测技术从单基因到多基因的进展促进了生物信息学飞速发展和恶性肿瘤概念的转变;体外细胞研究模型从单层的二维培养、原代培养向立体的三维构型发展,从而更好地重现肿瘤组织的细胞间交互作用与功能;体内动物研究模型由传统的致癌物诱导、细胞或组织形成移植瘤逐渐演变为基因编辑的动物模型或人源性肿瘤异种移植模型,从而可以针对性地研究相关基因在肿瘤发生发展中的作用;传统的临床研究也从简单的临床回顾性研究更多地向前瞻性研究转变,Ⅰ期/Ⅱ期/Ⅲ期临床研究,研究者发起的临床研究以及真实世界临床研究,这些研究为临床研究增添了活力。目前恶性肿瘤研究模型存在的主要不足包括模型的单一性、对肿瘤微环境的模拟不足、动物肿瘤模型与人类肿瘤差异性,以及缺乏对个性化医疗的考量。未来仍需要进一步研发和优化研究模型,并更有效地将不同模型整合起来,形成一个优化的整体实验模型系统。本文将系统回顾恶性肿瘤研究模型的演化并对相关模型进行阐述,为科研工作者进行恶性肿瘤的研究提供合理的研究模型。 展开更多
关键词 恶性肿瘤 研究模型 3D培养技术 肿瘤类器官培养 动物模型 人源肿瘤细胞系异种移植瘤 人源性肿瘤异种移植模型 基因检测 生物信息学 数字肿瘤学 智能肿瘤学
下载PDF
贵州不同芒果品种(系)果实香气成分研究
16
作者 刘清国 刘荣 +4 位作者 黄海 张正学 林迓 党志国 雷跃 《贵州农业科学》 CAS 2024年第11期92-101,共10页
【目的】测定贵州不同芒果品种(系)的香气成分及其相对含量,明确其香气特性,为选育优质芒果新品种提供参考。【方法】以金煌芒、台农1号芒和台芽芒等32个芒果品种(系)为试验材料,采用顶空固相微萃取-气质联用技术测定分析不同品种(系)... 【目的】测定贵州不同芒果品种(系)的香气成分及其相对含量,明确其香气特性,为选育优质芒果新品种提供参考。【方法】以金煌芒、台农1号芒和台芽芒等32个芒果品种(系)为试验材料,采用顶空固相微萃取-气质联用技术测定分析不同品种(系)的香气成分类别及其相对含量,明确其香气特性。【结果】金煌芒、台农1号芒和台芽芒等32个芒果品种(系)共检测出9类103种香气成分,依次为倍半萜烯类(25种)>单萜烯类(21种)>酯类(14种)>醇类(11种)>醛类=其他物质(10种)>酮类(8种)>酸类(3种)>芳香烃类(1种);以月桂烯、3-蒈烯、γ-松油烯、(E,E)-4,6-二甲基-2,4,6-辛三烯和反式石竹烯为芒果香气的基本组成成分。台芽芒的香气种类最多,为54种;椰香芒最少,仅28种。果实的醇类和酯类物质较少,且相对含量均小于10.00%。32个芒果品种(系)聚为2类,类群1包括生吃芒、桂七芒、爱文芒、鹰嘴芒和桂热10号芒;类群2分为2个分支,第一分支包括台牙芒、贵妃芒、QS-002、金兴芒、玉文芒、东镇红芒、热品2号芒、热农1号芒、红芒6号、黔山芒1号和凯特芒,其余16个芒果品种(系)归为第二分支。【结论】贵州不同芒果品种(系)果实的香气成分丰富,共检测出9类103种香气成分,其相对含量存在明显差异,以月桂烯、3-蒈烯、γ-松油烯、(E,E)-4,6-二甲基-2,4,6-辛三烯和反式石竹烯为芒果香气的基本组成成分。 展开更多
关键词 芒果 品种(系) 香气特性 顶空固相微萃取法 气相色谱-质谱分析 贵州
下载PDF
Non-Linear Phase Tomography Based on Fréchet Derivative
17
作者 Valentina Davidoiu Bruno Sixou +1 位作者 Max Langer Franoise Peyrin 《Advances in Computed Tomography》 2014年第4期39-50,共12页
Phase imaging coupled to micro-tomography acquisition has emerged as a powerful tool to investigate specimens in a non-destructive manner. While the intensity data can be acquired and recorded, the phase information o... Phase imaging coupled to micro-tomography acquisition has emerged as a powerful tool to investigate specimens in a non-destructive manner. While the intensity data can be acquired and recorded, the phase information of the signal has to be “retrieved” from the data modulus only. Phase retrieval is an ill-posed non-linear problem and regularization techniques including a priori knowledge are necessary to obtain stable solutions. Several linear phase recovery methods have been proposed and it is expected that some limitations resulting from the linearization of the direct problem will be overcome by taking into account the non-linearity of the phase problem. To achieve this goal, we propose and evaluate a non-linear algorithm for in-line phase micro-tomography based on an iterative Landweber method with an analytic calculation of the Fréchet derivative of the phase-intensity relationship and of its adjoint. The algorithm was applied in the projection space using as initialization the linear mixed solution. The efficacy of the regularization scheme was evaluated on simulated objects with a slowly and a strongly varying phase. Experimental data were also acquired at ESRF using a propagation-based X-ray imaging technique for the given pixel size 0.68 μm. Two regularization scheme were considered: first the initialization was obtained without any prior on the ratio of the real and imaginary parts of the complex refractive index and secondly a constant a priori value was assumed on ?. The tomographic central slices of the refractive index decrement were compared and numerical evaluation was performed. The non-linear method globally decreases the reconstruction errors compared to the linear algorithm and is achieving better reconstruction results if no prior is introduced in the initialization solution. For in-line phase micro-tomography, this non-linear approach is a new and interesting method in biomedical studies where the exact value of the a priori ratio is not known. 展开更多
关键词 PHASE Retrieval In-Line PHASE TOMOGRAPHY Inverse Problems NON-LINEAR Problem NON-LINEAR Optimization Fréchet derivative Coherent IMAGING FRESNEL Diffraction PHASE Contrast X-Ray IMAGING
下载PDF
神经胶质细胞系衍生神经营养因子和雄激素受体在手术诱导隐睾小鼠睾丸管周细胞中的表达
18
作者 吴飞 潮敏 +2 位作者 张殷 张晔 蒋加斌 《中山大学学报(医学科学版)》 CAS CSCD 北大核心 2024年第1期85-92,共8页
【目的】探讨神经胶质细胞系衍生神经营养因子(GDNF)和雄激素受体(AR)在隐睾症小鼠睾丸管周细胞中的表达水平及对隐睾症导致生精功能障碍的理论意义。【方法】30只5周龄雄性ICR小鼠采用随机数字表法随机分配至6组中,随机抽取3组15只小... 【目的】探讨神经胶质细胞系衍生神经营养因子(GDNF)和雄激素受体(AR)在隐睾症小鼠睾丸管周细胞中的表达水平及对隐睾症导致生精功能障碍的理论意义。【方法】30只5周龄雄性ICR小鼠采用随机数字表法随机分配至6组中,随机抽取3组15只小鼠进行手术诱导隐睾,其余3组为作为对照组进行假手术处理。分别于4 d、7 d、14 d后取各组睾丸组织,然后测量睾丸体积、观察睾丸组织病理,提取各组睾丸管周细胞后利用免疫荧光、Re⁃al-Time PCR和蛋白质印记法检测AR和GDNF的mRNA和蛋白的表达。【结果】对照组4 d、7 d、14 d小鼠的睾丸体积分别为(125.58±19.22)mm^(3)、(123.45±20.12)mm^(3)、(140.09±13.62)mm^(3);睾丸各级生精细胞排列整齐、层次清楚,可见较多精子细胞,生精小管周围管周细胞形态规则,呈梭形围绕小管周围,细胞厚度均一;ARmRNA的表达量分别为1.00±0.05、1.06±0.07、1.19±0.13GDNFmRNA的表达量分别为1.00±0.04、1.09±0.05、1.10±0.07;AR蛋白的表达量分别为1.01±0.01、0.79±0.02、1.01±0.04;GDNF蛋白的浓度分别为(18.68±0.43)pg/mL、(14.39±0.36)pg/mL、(16.88±0.37)pg/mL。隐睾组4 d、7 d、14 d小鼠的睾丸体积分别为(115.64±3.91)mm^(3)、(69.51±14.97)mm^(3)、(44.86±5.56)mm^(3);睾丸各级生精细胞排列紊乱、层次不清、结构破坏,曲细精管周围管周细胞萎缩、弯曲断裂;ARmRNA的表达量分别为0.76±0.06、0.53±0.04、0.29±0.02;GDNFmRNA的表达量分别为0.72±0.05、0.42±0.02、0.30±0.03;AR蛋白的表达量分别为0.54±0.02、0.98±0.04、0.31±0.01;GDNF蛋白的浓度分别为(8.50±0.34)pg/mL、(17.44±0.32)pg/mL、(6.83±0.34)pg/mL。上述指标与对照组相比,除了4 d的睾丸体积差异无统计学意义(P>0.05),其他均有统计学差异(P<0.05)。对照组中3个时间点的睾丸体积、AR和GDNF的mRNA、蛋白表达量的差异无统计学意义(P>0.05),隐睾组3个时间点的睾丸体积、AR和GDNF的mRNA、蛋白表达量呈逐渐下降趋势且各组之间的差异均有统计学意义(P<0.05)。【结论】在手术诱导隐睾小鼠中,睾丸管周细胞的AR和GDNF的表达水平随着诱导时间的延长呈现显著下降。AR和GDNF在隐睾症介导睾丸管周细胞功能的损伤中有重要作用。本研究为阐明隐睾症导致生精功能障碍的机制研究提供理论基础。 展开更多
关键词 隐睾症 管周细胞 胶质细胞系衍生神经营养因子 雄激素受体
下载PDF
三线建设工业遗产保护与旅游融合:价值解读、模式与路径
19
作者 刘安乐 明庆忠 代稳 《西南科技大学学报(哲学社会科学版)》 2024年第1期18-25,42,共9页
三线建设工业遗产是记录中国军工史、工业化史和党史的重要载体,是一种独特的红色旅游资源和工业遗产旅游资源。为了促进三线建设工业遗产保护与融合发展,本文采用文献分析、实地调研等方法,界定了三线建设工业遗产的概念,解读了三线建... 三线建设工业遗产是记录中国军工史、工业化史和党史的重要载体,是一种独特的红色旅游资源和工业遗产旅游资源。为了促进三线建设工业遗产保护与融合发展,本文采用文献分析、实地调研等方法,界定了三线建设工业遗产的概念,解读了三线建设工业遗产旅游价值,提出三线建设工业遗产保护与旅游融合发展路径与对策,为三线建设工业遗产与旅游融合发展提供理论指导。 展开更多
关键词 三线建设工业遗产 价值解读 旅游融合发展模式 主体功用性价值 主体衍生功用性价值
下载PDF
骨肉瘤组织中GFRA1、FBN1表达水平及意义
20
作者 张畅 李小双 +2 位作者 廉凯 徐进 李晶 《河北医药》 CAS 2024年第2期223-226,共4页
目的探讨胶质细胞系源性神经营养因子受体1(GFRA1)、原纤维蛋白-1(FBN1)在骨肉瘤组织中表达水平及意义。方法收集2017年9月至2019年9月住院手术的66例骨肉瘤患者治疗精细切除骨肉瘤组织标本及癌旁组织标本,同时收集整理其临床分期、肿... 目的探讨胶质细胞系源性神经营养因子受体1(GFRA1)、原纤维蛋白-1(FBN1)在骨肉瘤组织中表达水平及意义。方法收集2017年9月至2019年9月住院手术的66例骨肉瘤患者治疗精细切除骨肉瘤组织标本及癌旁组织标本,同时收集整理其临床分期、肿瘤直径、肿瘤分化程度等临床资料。采用免疫组织化学法检测GFRA1、FBN1蛋白表达;骨肉瘤组织GFRA1、FBN1表达与患者预后的关系采用Kaplan-Meier法分析;多因素Logistic回归分析骨肉瘤患者预后的影响因素。结果与癌旁组织相比,骨肉瘤组织中GFRA1、FBN1阳性表达率明显较高(P<0.05)。GFRA1、FBN1的表达与骨肉瘤患者的临床分期、分化程度、是否发生肺转移、软组织是否浸润有关(P<0.05),与患者性别、年龄、肿瘤直径、肿瘤位置无关(P>0.05);骨肉瘤组织GFRA1、FBN1阳性表达患者3年生存率低于FBN1阴性表达患者(P<0.05)。GFRA1、FBN1阳性表达、肿瘤转移、软组织浸润是骨肉瘤患者预后的独立危险因素(P<0.05)。结论GFRA1、FBN1的表达与骨肉瘤患者的临床病理特征及预后有关,可以作为骨肉瘤患者预后评估的指标。 展开更多
关键词 骨肉瘤 GFRA1 FBN1 病理特征
下载PDF
上一页 1 2 64 下一页 到第
使用帮助 返回顶部