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进化(话剧小品)
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作者 李帆 《四川戏剧》 北大核心 2001年第3期45-45,共1页
关键词 《进化》 李帆 文学作品 戏剧文学 话剧小品 中国 当代作品
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《进化》——夭折的外星生物史
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作者 张丽 《中学科技》 2007年第1期10-11,共2页
《进化》是一部充满奇思妙想的科幻轻喜剧,讲述了当一块陨石坠落到美国的荒漠中后所引发的令人恐怖的连锁事件。原来这块陨石记载着外星的生命印记,它在地球上开始了生命的进化——没几周,这些外星生命就从单细胞的有机体发展到了鸟... 《进化》是一部充满奇思妙想的科幻轻喜剧,讲述了当一块陨石坠落到美国的荒漠中后所引发的令人恐怖的连锁事件。原来这块陨石记载着外星的生命印记,它在地球上开始了生命的进化——没几周,这些外星生命就从单细胞的有机体发展到了鸟类和灵长类生物,把坠落地的城市搞得一团糟。它们的进化如此飞速,或许不久就能取代人类,支配整个世界了!不过别担心,这可是一出喜剧,我们来看看编剧是如何实现喜剧结局的吧。 展开更多
关键词 外星生命 生物史 进化 灵长类 有机体 单细胞 坠落 陨石 《进化》
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引人入胜的智力探险史──读《进化思想史》
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作者 陈蓉霞 《中国图书评论》 CSSCI 北大核心 2000年第3期32-33,共2页
关键词 《进化思想史》 图书评介 英国 哲学思想
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进化论的革命 宇宙学的创新——评陶同新著《进化中的宇宙》
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作者 徐和笙 《北方论丛》 2003年第3期131-132,共2页
 科学是一个过程,任何理论都不会是亘古真理,随着时间的发展都将被新的理论所突破,达尔文的生物进化论也不例外。陶同的新著《进化中的宇宙》首次提出了"宇宙是在进化"这一科学观点,即是对进化论的突破。
关键词 达尔文 进化 《进化的宇宙》 宇宙进化
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《进化岛》:女性主义下的后人类寓言
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作者 黄超 《艺术科技》 2020年第21期53-54,共3页
《进化岛》是由法国女导演露西尔·哈兹哈利罗维克(Lucile Hadzihalilovic)于2015年拍摄的一部恐怖剧情电影,赋予了浓郁的女性主义和后人类主义色彩。本文以《进化岛》为文本,分别运用女性主义理论与后人类主义理论对其进行简短的分... 《进化岛》是由法国女导演露西尔·哈兹哈利罗维克(Lucile Hadzihalilovic)于2015年拍摄的一部恐怖剧情电影,赋予了浓郁的女性主义和后人类主义色彩。本文以《进化岛》为文本,分别运用女性主义理论与后人类主义理论对其进行简短的分析,并进行两种理论下的解读对比。 展开更多
关键词 女性主义 后人类主义 《进化岛》
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《地下城与勇士》华丽进化喜迎虎年
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作者 minson 《家用电脑与游戏》 2010年第2期92-93,共2页
临近农历新年,随着太岁的换位轮值,《地下城与勇士》也以一个崭新的姿态面向广大的玩家。由界面操作的友好提升、更低级难度的地城削弱和更高级别深渊地城“恶魔”的出现、圣职者及神枪手的改版、更多的全新炫酷的技能、更多全新地图... 临近农历新年,随着太岁的换位轮值,《地下城与勇士》也以一个崭新的姿态面向广大的玩家。由界面操作的友好提升、更低级难度的地城削弱和更高级别深渊地城“恶魔”的出现、圣职者及神枪手的改版、更多的全新炫酷的技能、更多全新地图的挑战,尽在地下城与勇士第五章《进化之光》。 展开更多
关键词 《地下城与勇士》 网络游戏 电脑游戏 《进化之光》
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基于改进YOLOv8的轻量化小麦病害检测方法 被引量:14
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作者 马超伟 张浩 +3 位作者 马新明 王键霖 张永爽 张小艾 《农业工程学报》 EI CAS CSCD 北大核心 2024年第5期187-195,共9页
为提高小麦病害检测精度,实现将模型方便快速部署到移动端,该研究提出了一种基于改进YOLOv8的轻量化小麦病害检测方法。首先,使用PP-LCNet模型替换YOLOv8网络结构的骨干网络,并在骨干网络层引入深度可分离卷积(depthwise separable conv... 为提高小麦病害检测精度,实现将模型方便快速部署到移动端,该研究提出了一种基于改进YOLOv8的轻量化小麦病害检测方法。首先,使用PP-LCNet模型替换YOLOv8网络结构的骨干网络,并在骨干网络层引入深度可分离卷积(depthwise separable convolution, DepthSepConv)结构,减少模型参数量,提升模型检测性能;其次,在颈部网络部分添加全局注意力机制(global attention mechanism, GAM)模块,强化特征中语义信息和位置信息,提高模型特征融合能力;然后,引入轻量级通用上采样内容感知重组(content-aware reassembly of features,CARAFE)模块,提高模型对重要特征的提取能力;最后,使用Wise-IoU(weighted interpolation of sequential evidence for intersection over union)边界损失函数代替原损失函数,提升网络边界框回归性能和对小目标病害的检测效果。试验结果表明,对于大田环境下所采集的小麦病害数据集,改进后模型的参数量及模型大小相比原YOLOv8n基线模型分别降低了12.5%和11.3%,同时精确度(precision)及平均精度均值(mean average precision,m AP)相较于原模型分别提高了4.5和1.9个百分点,优于其他对比目标检测算法,可为小麦病害检测无人机等移动端检测装备的部署和应用提供参考。 展开更多
关键词 图像识别 深度学习 目标检测 轻量化 小麦病害 YOLOv8 PP-LCNet
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以科技创新促进节能减排的战略研究 被引量:1
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作者 史益博 《当代化工研究》 CAS 2024年第1期194-196,共3页
科技创新技术在促进节能减排方面起着重要的作用。通过提高能源利用效率和减少排放,可以实现可持续发展。当前,人工智能、大数据分析和机器学习等技术在能源管理和工业生产方面的应用正处于快速发展阶段。同时,开发新材料也是重要的科... 科技创新技术在促进节能减排方面起着重要的作用。通过提高能源利用效率和减少排放,可以实现可持续发展。当前,人工智能、大数据分析和机器学习等技术在能源管理和工业生产方面的应用正处于快速发展阶段。同时,开发新材料也是重要的科技创新方向之一。通过持续加大对科技创新的投入,我们可以进一步推动科技创新的发展,为节能减排做出更大的贡献。 展开更多
关键词 科技创新 节能减排 创新技术
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Genetic Variation of Mitochondrial D-loop Region and Evolution Analysis in Some Chinese Cattle Breeds 被引量:13
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作者 贾善刚 陈宏 +4 位作者 张桂香 王志刚 雷初朝 姚茹 韩旭 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第6期510-518,共9页
The complete mitochondrial D-loop region from 123 individuals in 12 Chinese cattle breeds and two individuals in Germany Yellow cattle breed was sequenced and analyzed. The results were shown as follows: 93 variation... The complete mitochondrial D-loop region from 123 individuals in 12 Chinese cattle breeds and two individuals in Germany Yellow cattle breed was sequenced and analyzed. The results were shown as follows: 93 variations and 57 haplotypes were detected, and the average number of nucleotide difference was 22.708, nucleotide diversity (π) was 0.0251 ± 0.00479, and haplotype diversity (Hd) was 0.888 ± 0.026, indicating very high genetic diversity in Chinese cattle breeds. In the Neighbor-Joining tree, 13 cattle breeds were divided into two main clades, Bos taurus and Bos indicus; new Clade Ill had only one sequence from Apeijiaza cattle breed in Tibet, which was similar to that of yak at a higher level than other cattle breeds, proving the introgression of genes from the yak. The proportions of Bos taurus and Bos indicus were 64.3 % and 35.7 % respectively in Xigaze Humped cattle breed, and 50.0% and 50.0% respectively in Apeijiaza cattle breed, which revealed that Tibet cattle included Bos indicus haplotypes. The importance of Yunnan cattle in the origin of Chinese cattle was also confirmed based on their abundant haplotypes. Then, a very special haplotype il discovered in 27 Chinese cattle breeds, including 11 breeds in this study and 16 breeds in the GenBank, played the role of a nucleus in Chinese zebu and was further discussed. At the same time, the construction of Chinese zebu core group based on haplotype il validated the distinct origin of Bos indicus in Tibet, which was different from that of the other cattle breeds with zebu haplotypes in China. 展开更多
关键词 ORIGIN evolution CATTLE mitochondrial D-loop genetic diversity
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Sequence Variation and Molecular Evolution of Hormone-Sensitive Lipase Genes in Species of Bovidae 被引量:8
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作者 马志杰 钟金城 +3 位作者 陈智华 刘丽 常怀普 罗晓林 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期26-34,共9页
The partial sequences of exon Ⅰ of hormone-sensitive lipase (HSL) genes in yak (Bos grunniens), cattle (Bos taurus), zebu (Bos indicus), and buffalo (Bubalus bubalis) were analyzed. Comparisons of these seq... The partial sequences of exon Ⅰ of hormone-sensitive lipase (HSL) genes in yak (Bos grunniens), cattle (Bos taurus), zebu (Bos indicus), and buffalo (Bubalus bubalis) were analyzed. Comparisons of these sequences and the deduced amino acid sequences with the homologous HSL gene and protein sequences in other mammalian species including pig (Sus scrofa), human (Homo sapiens), mouse (Mus musculus), and rat (Rattus sp.) retrieved from the GenBank were carried out and finally a phylogenetic tree was constructed using the partial DNA sequences of the HSL genes in all species. The results showed that the homologies of the partial exon Ⅰ sequences of the HSL genes between yak and cattle, zebu, buffalo, pig, human, mouse, and rat were as high as 99.8%, 99.6%, 97.4%, 90.6%, 88.4%, 83.5%, and 82.3%, respectively. This was accompanied by highly homologous amino acid sequences of the HSLs: 100%, 100%, 98.2%, 94.0%, 92.2%, 89.8%, and 89.8% identity, respectively. There are more transitions, less transversions, and no insertion or deletion in variable nucleotides of the HSL genes between the yak and other species. The majority of the variable mutations was synonymous and was found most frequently at the third codon, followed by the first and second codons, a finding that was in accordance with the neutralism hypothesis for molecular evolution. In the phylogenetic tree, the cattle and zebu were clustered together first, followed by the yak, buffalo, pig, human, mouse, and rat. This was in agreement with taxonomy suggesting that the partial sequences of exon Ⅰ of the HSL genes were useful in constructing the phylogenetic tree of mammalian species. Among the four species of Bovidae, genetic differentiation in the HSL genes between yak and buffalo is equivalent to that between buffalo and cattle and between buffalo and zebu. Furthermore, the genetic distances in the HSL genes are much smaller between yak, cattle, and zebu than those between each of the three species and the buffalo. Therefore, it is reasonable to consider yak as an independent species of the genus Bos. 展开更多
关键词 BOVIDAE HSL gene PHYLOGENY evolution
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Recent Progress in Elucidating the Structure, Function and Evolution of Disease Resistance Genes in Plants 被引量:28
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作者 刘金灵 刘雄伦 +1 位作者 戴良英 王国梁 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第9期765-776,共12页
Plants employ multifaceted mechanisms to fight with numerous pathogens in nature. Resistance (R) genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding... Plants employ multifaceted mechanisms to fight with numerous pathogens in nature. Resistance (R) genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding pathogen effectors or associated protein(s) to activate plant immune responses at the site of infection. Up to date, over 70 R genes have been isolated from various plant species. Most R proteins contain conserved motifs such as nucleotide-binding site (NBS), leucine-rich repeat (LRR), Toll-interleukin-1 receptor domain (TIR, homologous to cytoplasmic domains of the Drosophila Toll protein and the manamalian intefleukin-1 receptor), coiled-coil (CC) or leucine zipper (LZ) structure and protein kinase domain (PK). Recent results indicate that these domains play significant roles in R protein interactions with effector proteins from pathogens and in activating signal transduction pathways involved in innate immunity. This review highlights an overview of the recent progress in elucidating the structure, function and evolution of the isolated R genes in different plant-pathogen interaction systems. 展开更多
关键词 plant disease resistance gene defense signaling evolution of resistance gene cluster
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Diversity of Bmp15 and Gdf9 Genes in White Goat of Guizhou Province and Evolution of the Encoded Proteins 被引量:6
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作者 冉雪琴 林尖兵 +2 位作者 杜智勇 覃成 王嘉福 《Zoological Research》 CAS CSCD 北大核心 2009年第6期593-602,共10页
Members of the transforming growth factor-beta superfamily, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP 15), have crucial roles in fecundity of sheep. Our previous investigation c... Members of the transforming growth factor-beta superfamily, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP 15), have crucial roles in fecundity of sheep. Our previous investigation confirmed that the fecundity mutations of sheep presented in highly prolific White goat individuals of Guizhou province. To illuminate other polymorphisms in Bmpl5 and Gdfl) genes and the relationship of these mutations with function, we cloned and characterized the coding region of Bmp15 and Gdfl). Molecular models of BMP15 and GDF9 mature peptide of White goat were constructed based on the homology of human BMP7 experimental tertiary structure. Two exons encoded prepropeptide of 394 amino acids in BMPI5 and 453 residues in GDF9, respectively. Apart from the FecXs mutation (S99I) in BMP15 and V791 mutation in GDF9 confirmed in White goat previously, other seven and three polymorphism sites were detected from BMP15 and GDF9 mature peptides, respectively. S32G, N66H, S99I/P99I and G107R in BMP15 could be important for the binding of dimer to receptors. Changes of P78Q and V79I in GDF9 might affect the binding of dimer to receptor type t. Comparing the length of BMP 15 and GDF9 prepropeptide in vertebrates, an increase in length of BMP 15 presented along with the protein evolution from fish to mammal and the divergence of the N-terminus residues in matured BMP15 peptide might contribute to the sensitive control on the fertility of animal species with low ovulation rate. These findings gave a valuable explanation for the correlation of mutations in Bmpl5 and Gdfl) genes with the control on fecundity of White goat and supported the notion that they were the pivotal factors in female fertility of White goat in Guizhou province. 展开更多
关键词 BMP15 GDF9 Gene EVOLUTION White goat
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Damage and fracture behavior and spatio-temporal evolution of acoustic emission of sandstone before and after laser radiation
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作者 GAO Ming-zhong LIU Jun-jun +6 位作者 LIChun-xiang YANG Ben-gao LI Fei ZHOU Xue-min YANG Lei YANG Zun-dong XIE Jing 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3264-3280,共17页
Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to su... Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to such radiation.The uniaxial compressive strength of sandstone notably decreases by 22.1%–54.7%following exposure to a 750 W laser for 30 s,indicating a substantial weakening effect.Furthermore,the elastic modulus and Poisson ratio of sandstone exhibit an average decrease of 33.7%and 25.9%,respectively.Simultaneously,laser radiation reduces the brittleness of sandstone,increases the dissipated energy proportion,and shifts the failure mode from tensile to tension-shear composite failure.Following laser radiation,both the number and energy of acoustic emission events in the sandstone register a substantial increase,with a more dispersed distribution of these events.In summary,laser radiation induces notable damage to the mechanical properties of sandstone,leading to a substantial decrease in elastic energy storage capacity.Laser rock breaking technology is expected to be applied in hard rock breaking engineering to significantly reduce the difficulty of rock breaking and improve rock breaking efficiency. 展开更多
关键词 laser rock breaking efficient drilling acoustic emission mechanical damage strength reduction
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Diversity of Sucking Lice on Small Mammals in the Surrounding Areas of Erhai Lake in Yunnan,China 被引量:3
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作者 董文鸽 郭宪国 +2 位作者 门兴元 钱体军 吴滇 《Entomotaxonomia》 CSCD 北大核心 2009年第1期68-80,共13页
An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were c... An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were captured and identified into 7 families, 15 genera and 21 species in 4 orders (Rodentia, Insectivora, Scandentia and Carnivora), while t4 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura, The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain. The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity, abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking lice and their corresponding hosts. A certain species of hosts usually have their fixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mammal host in different oriented areas of Erhai Lake are homologous. The results strongly suggest a close relationship of co-evolution between sucking lice and their hosts. 展开更多
关键词 ANOPLURA small mammal species diversity community ecology co-evolution.
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Effects of Evolution Rate of Cyt b and 12S rRNA Genes on Constructing Phylogenetic Trees 被引量:2
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作者 王利利 彭建军 +4 位作者 于冬梅 胡诗佳 高赛飞 傅美兰 刘曦庆 《Agricultural Science & Technology》 CAS 2011年第1期58-61,共4页
[Objective]The aim was to prove that the mitochondrial genes of Cyt b and 12S rRNA with different evolutional rates have effects on the topological structures of phylogenetic trees.[Method]The complete sequences of Cy... [Objective]The aim was to prove that the mitochondrial genes of Cyt b and 12S rRNA with different evolutional rates have effects on the topological structures of phylogenetic trees.[Method]The complete sequences of Cyt b and 12S rRNA from 15 species in 12 families of snakes were downloaded and extracted from GenBank,while their molecular phylogenetic trees were constructed by Maximum Likelihood(ML) method with GTR +I +G substitute model based on PAUP4.0 software.[Result]With the same software,methods and species,the difference in topological structures of phylogenetic trees was mainly due to different evolutional rates of Cyt b and 12S rRNA genes.[Conclusion]In studies on phylogenetic trees,aimed to different research species and purposes,phylogenetic trees should be constructed by choosing the correct and appropriate genes. 展开更多
关键词 Molecular phylogeny SNAKE Cyt b 12S rRNA Evolution rate
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EVOLUTIONARY GAME OF DYNAMIC KNOWLEDGE EXCHANGING IN KNOWLEDGE INTERACTION 被引量:3
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作者 马静 方志耕 袁玲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期304-310,共7页
Characteristics of knowledge exchanging behavior among individual agents in a knowledge dynamic interaction system are studied by using the game theory. An analytic model of evolutionary game of continuous dynamic kno... Characteristics of knowledge exchanging behavior among individual agents in a knowledge dynamic interaction system are studied by using the game theory. An analytic model of evolutionary game of continuous dynamic knowledge interaction behavior is founded based on the structure of the evolutionary game chain. Possible evolution trends of the model are discussed. Finally, evolutionary stable strategies (ESSs) of knowledge transactions among individual agents in the knowledge network are identified by simulation data. Stable charicteristics of ESS in a continuous knowledge exchanging team help employee to communicate and grasp the dynamic regulation of shared knowledge. 展开更多
关键词 knowledge management knowledge interaction evolutionary game evolutionary stable strategy
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Molecular Composition and Evolution of the Chalcone Synthase (CHS) Gene Family in Five Species of Camellia (Theaceae) 被引量:5
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作者 杨俊波 田欣 +1 位作者 李德铢 郭振华 《Acta Botanica Sinica》 CSCD 2003年第6期659-666,共8页
The molecular composition and evolution of the chalcone synthase (CHS) gene family from five species in Camellia (Theaceae) are explored in this study. Sixteen CHS exon 2 from four Camellia species were amplified from... The molecular composition and evolution of the chalcone synthase (CHS) gene family from five species in Camellia (Theaceae) are explored in this study. Sixteen CHS exon 2 from four Camellia species were amplified from total DNA by PCR method. Three sequences of the fifth species in Camellia and two sequences of Glycine max as the designated outgroups were obtained from GenBank. Our results indicated that CHS gene family in Camellia was differentiated to three subfamilies (A, B, C) during the evolutionary history with six groups (A1, A2, A3, BI, B2, C). Among them, only group A2 was possessed by all five species in this study. However, the other five groups were detected only in some species of the plants studied. All members of CHS gene family in this study had high sequence similarity, more than 90% among the members in the same subfamily and more than 78% among different subfamilies at nucleotide level., According to the estimated components of amino acids, the function of CHS genes in Camellia had been diverged. The nucleotide substitutions of the different groups were not identical. Based on phylogenetic analyse inferred from sequences of CHS genes and their deduced amino acid sequences, we concluded that the CHS genes with new function in this genus were evolved either by mutations on several important sites or by accumulation of the mutations after the gene duplication. A further analysis showed that the diversification of CHS genes in Camellia still occurred recently, and the evolutionary models were different to some extant among different species. So we assumed that the different evolutionary models resulted from the impacts of variable environmental elements after the events of speciation. 展开更多
关键词 CAMELLIA chalcone synthase (CHS) gene family molecular evolution
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Fast algorithm for constructing neighbor-joining phylogenetic trees 被引量:3
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作者 陈宁涛 王能超 施保昌 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期176-179,共4页
To improve the performance of Saitou and Nei's algorithm (SN) and Studier and Keppler's improved algorithm (SK) for constructing neighbor-joining phylogenetic trees and reduce the time complexity of the computat... To improve the performance of Saitou and Nei's algorithm (SN) and Studier and Keppler's improved algorithm (SK) for constructing neighbor-joining phylogenetic trees and reduce the time complexity of the computation, a fast algorithm is proposed. The proposed algorithm includes three techniques. First, a linear array A[N] is introduced to store the sum of every row of the distance matrix (the same as SK), which can eliminate many repeated computations. Secondly, the value of A [i] is computed only once at the beginning of the algorithm, and is updated by three elements in the iteration. Thirdly, a very compact formula for the sum of all the branch lengths of operational taxonomic units (OTUs) i and j is designed, and the correctness of the formula is proved. The experimental results show that the proposed algorithm is from tens to hundreds times faster than SN and roughly two times faster than SK when N increases, constructing a tree with 2 000 OTUs in 3 min on a current desktop computer. To earn the time with the cost of the space and reduce the computations in the innermost loop are the basic solutions for algorithms with many loops. 展开更多
关键词 phylogenetic tree neighbor-joining method fast algorithm progressive multiple alignment
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Genomic Sequencing and Molecular Characteristics of A Very Virulent Strain of Infectious Bursal Disease Virus Isolated in China 被引量:4
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作者 祁小乐 高立 +9 位作者 秦立廷 邓小芸 吴关 张礼洲 余飞 任宪刚 高玉龙 高宏雷 王永强 王笑梅 《Agricultural Science & Technology》 CAS 2011年第12期1946-1949,共4页
[Objective] The paper was to determine the genomic sequence of a very virulent strain of infectious bursal disease virus(IBDV),and study its molecular characteristics.[Method] A very virulent strain(vvIBDV)(HLJ-0... [Objective] The paper was to determine the genomic sequence of a very virulent strain of infectious bursal disease virus(IBDV),and study its molecular characteristics.[Method] A very virulent strain(vvIBDV)(HLJ-0504) of infectious bursal disease virus(IBDV) with special characters was isolated in China and its genome was sequenced.[Result] Sequence analysis showed that segment A of HLJ-0504 was derived from vvIBDV,while segment B was from a distinct ancestor.The morbidity and mortality of HLJ-0504 was 100% and 86.7%to SPF chickens,respectively.[Conclusion] vvIBDV with distinct segment B were still circulating and the evolution of IBDV was diversified in China.Besides,it is hard to imagine that the virulence of IBDV is determined solely by segment A or B. 展开更多
关键词 Infectious bursal disease virus(IBDV) GENOME EVOLUTION VIRULENCE
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Relationship between Rice Cultural Diversity and Ecological Environment in Yunnan Province of China 被引量:3
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作者 曾亚文 杜娟 +3 位作者 普晓英 罗曦 杨树明 杨涛 《Agricultural Science & Technology》 CAS 2012年第10期2247-2256,共10页
[Objective] This paper aims to confirm that Yunnan is one origin center of rice and human in the world.[Method] The complicated and unique ecological environment in Yunnan makes Yunnan Province the largest center of g... [Objective] This paper aims to confirm that Yunnan is one origin center of rice and human in the world.[Method] The complicated and unique ecological environment in Yunnan makes Yunnan Province the largest center of genetic diversity and cultural diversity of rice and human being as well as the cradle of human childhood.[Result] The genetic diversity and cultural diversity of rice and human being is closely related to the ecosystem diversity.Rice civilization in Yunnan can be divided into four types,including the diversity center region of rice civilization in southwestern Yunnan,diffusion region of rice civilization of Hani-Zhuang in southern Yunnan,rice civilization region of water-drought rotation in central Yunnan and poverty region of rice civilization in northern Yunnan.Southwestern Yunnan is not only the center of genetic ecological diversity and rice cultural diversity,but also the center of origin and diversity of crop genetic diversity.It is not only a transitional region among East Asia continent,South Asian sub-continent and Indo-China Peninsula,but also a core integration area of Chinese culture,Indian culture and Mid-south Peninsula culture which all merge with the local culture.[Conclusion] Yunnan is one common sphere where the origin of human evolution is closely related to the origin of rice evolution. 展开更多
关键词 Rice culture Ecological environment Origin evolution Human being YUNNAN
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