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猪细小病毒研究近况 被引量:5
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作者 尤永进 徐泉兴 周智爱 《上海农业学报》 CSCD 1995年第3期90-96,共7页
猪细小病毒(PorcineParvovirus,PPV)是一自主型细小病毒(Autonomousparvovirus),它是引起畸胎的主要因素之一。通常,头胎怀孕母猪感染了PPV之后,可引起繁殖障碍,主要症状为流产、... 猪细小病毒(PorcineParvovirus,PPV)是一自主型细小病毒(Autonomousparvovirus),它是引起畸胎的主要因素之一。通常,头胎怀孕母猪感染了PPV之后,可引起繁殖障碍,主要症状为流产、不孕、产死胎、木乃伊胎等,给养猪业带来巨大经济损失。近30年来的研究工作揭示了PPV的各种特性,特别是80年代以来,分子生物学和基因工程技术的运用,使我们能够从分子水平和基因水平去了解PPV,探索诊治途径。本文对PPV近10年来在分子生物学方面的研究状况作一综述性介绍,内容主要涉及PPV的基因构造、多肽结构、感染机制及基因工程疫苗研究等方面,并对这些研究进展与趋势加以讨论。 展开更多
关键词 猪细小病毒 PPV 基因构造 多肽结构 感染
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我国已培育出较完整的太空蔬菜品系
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《中国科技财富》 2003年第11期96-96,共1页
关键词 中国 太空蔬菜 返回式航天器 空间诱变育种 太空育种 基因构造
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BUD2,encoding an S-adenosylmethionine decarboxylase,is required for Arabidopsis growth and development 被引量:15
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作者 Chunmin Ge Xia Cui +5 位作者 Yonghong Wang Yuxin Hu Zhiming Fu Dongfen Zhang Zhukuan Cheng Jiayang Li 《Cell Research》 SCIE CAS CSCD 2006年第5期446-456,共11页
Polyamines are implicated in regulating various developmental processes in plants, but their exact roles and how they govern these processes still remain elusive. We report here an Arabidopsis bushy and dwarf mutant, ... Polyamines are implicated in regulating various developmental processes in plants, but their exact roles and how they govern these processes still remain elusive. We report here an Arabidopsis bushy and dwarf mutant, bud2, which results from the complete deletion of one member of the small gene family that encodes S-adenosylmethionine decarboxylases (SAMDCs) necessary for the formation of the indispensable intermediate in the polyamine biosynthetic pathway. The bud2 plant has enlarged vascular systems in inflorescences, roots, and petioles, and an altered homeostasis ofpolyamines. The double mutant of bud2 and samdcl, a knockdown mutant of another SAMDC member, is embryo lethal, demonstrating that SAMDCs are essential for plant embryogenesis. Our results suggest that polyamines are required for the normal growth and development of higher plants. 展开更多
关键词 BUD2 polyamines EMBRYOGENESIS plant architecture ARABIDOPSIS
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Work Organization Model Applied on Smallholder Dairy Farms in Brazil
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作者 Claudilaine Caldas de Oliveira Antonio Renato Pereira Moro Leandra Ulbricht 《Journal of Agricultural Science and Technology(A)》 2017年第8期567-576,共10页
This research identified difficulties faced by dairy farmers in family farming, describing this diagnosis through ergonomic demand items (EDIs). The objective was to elaborate an organization model of work related t... This research identified difficulties faced by dairy farmers in family farming, describing this diagnosis through ergonomic demand items (EDIs). The objective was to elaborate an organization model of work related to dairy farming (WRDF). As a methodology, a descriptive exploratory study was carried out in 14 family dairy farms that were visited and had their activities monitored. As main results, 11 EDIs were identified. The ones grouped in the infrastructure factor showed the highest resolution priority. The WRDF model was composed of three categories: management, public policies management and infrastructure, which were further subdivided into technical and social aspects. From this perspective, it is believed that the implementation of the model can bring organizational improvement, once adjustments are made in the procedures and working conditions. This study sheds light on the conditions that need to be resolved with higher priority so that the farmers will remain in the dairy business. 展开更多
关键词 Milk production Brazil dairy farming ERGONOMICS work environment.
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异尖科线虫线粒体基因组序列的生物信息学分析 被引量:3
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作者 王旭 贾海燕 +6 位作者 米荣升 黄燕 杨衡 张烨华 张晓丽 韩先干 陈兆国 《中国病原生物学杂志》 CSCD 北大核心 2018年第12期1338-1343,共6页
目的了解异尖科线虫线粒体基因组序列特性及其在分子分类和系统进化研究中的价值。方法从NCBI网站获得5种异尖科线虫的线粒体基因组序列数据,应用ClustalW、MEGA7、ARWEN进行核苷酸与编码氨基酸比对;利用ESPript和PyMOL软件分析COX1蛋... 目的了解异尖科线虫线粒体基因组序列特性及其在分子分类和系统进化研究中的价值。方法从NCBI网站获得5种异尖科线虫的线粒体基因组序列数据,应用ClustalW、MEGA7、ARWEN进行核苷酸与编码氨基酸比对;利用ESPript和PyMOL软件分析COX1蛋白一级结构,比较各蛋白三级结构模型。结果异尖线虫科线粒体DNA为双链闭环分子,长度为1.32~1.40kb。共有36个以相同方向排列的基因,其中编码蛋白质的基因12个,编码tRNA的基因22个(含亮氨酸-tRNA和丝氨酸-tRNA基因各2个,其余18种氨基酸tRNA各1个),编码rRNA的基因2个(分别为16S核糖体RNA(rRNA)和12SrRNA)。在12个蛋白编码基因中,CYTB和Nad2基因进化速率快,而cox1和nad4L基因则保守。线粒体tRNA长度为52~65bp,数目在6~9个之间,其中布兰地线虫(A.berlandi)的tRNA数目较多,为9个,而对盲囊线虫(C.ogmorhini)和简单异尖线虫(A.simplex)均为6个。tRNA二级结构多为经典的三叶草结构,少数为D-loop结构。简单异尖线虫与派氏异尖线虫(A.pegreffii)亲缘关系较近,拟地新线虫(P.decipiens)和简单异尖线虫与派氏异尖线虫的亲缘关系较远,对盲囊线虫与以上各虫种的亲缘关系较远。编码蛋白序列同源性比对显示,对盲囊线虫的COX1与其他4种异尖线虫差异较大,有17个氨基酸与其他4种不相同。氨基酸序列三级结构比对显示,对盲囊线虫的COX1有两处位点的折叠与其他线虫存在差异。结论异尖科线虫线粒体基因组分布均一,排列紧密,种间编码的蛋白质序列差异较小。A.pegreffii和A.simplex与A.berlandi的同源性较高,COX1可以作为异尖科线虫中重要的标志性蛋白。 展开更多
关键词 异尖科线虫 线粒体基因 生物信息学 基因构造 微进化
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Mitogenomic analysis of the genus Panthera 被引量:3
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作者 WEI Lei WU XiaoBing +1 位作者 ZHU LiXin JIANG ZhiGang 《Science China(Life Sciences)》 SCIE CAS 2011年第10期917-930,共14页
The complete sequences of the mitochondrial DNA genomes of Panthera tigris,Panthera pardus,and Panthera uncia were determined using the polymerase chain reaction method.The lengths of the complete mitochondrial DNA se... The complete sequences of the mitochondrial DNA genomes of Panthera tigris,Panthera pardus,and Panthera uncia were determined using the polymerase chain reaction method.The lengths of the complete mitochondrial DNA sequences of the three species were 16990,16964,and 16773 bp,respectively.Each of the three mitochondrial DNA genomes included 13 protein-coding genes,22 tRNA,two rRNA,one O L R,and one control region.The structures of the genomes were highly similar to those of Felis catus,Acinonyx jubatus,and Neofelis nebulosa.The phylogenies of the genus Panthera were inferred from two combined mitochondrial sequence data sets and the complete mitochondrial genome sequences,by MP (maximum parsimony),ML (maximum likelihood),and Bayesian analysis.The results showed that Panthera was composed of Panthera leo,P.uncia,P.pardus,Panthera onca,P.tigris,and N.nebulosa,which was included as the most basal member.The phylogeny within Panthera genus was N.nebulosa (P.tigris (P.onca (P.pardus,(P.leo,P.uncia)))).The divergence times for Panthera genus were estimated based on the ML branch lengths and four well-established calibration points.The results showed that at about 11.3 MYA,the Panthera genus separated from other felid species and then evolved into the several species of the genus.In detail,N.nebulosa was estimated to be founded about 8.66 MYA,P.tigris about 6.55 MYA,P.uncia about 4.63 MYA,and P.pardus about 4.35 MYA.All these estimated times were older than those estimated from the fossil records.The divergence event,evolutionary process,speciation,and distribution pattern of P.uncia,a species endemic to the central Asia with core habitats on the Qinghai-Tibetan Plateau and surrounding highlands,mostly correlated with the geological tectonic events and intensive climate shifts that happened at 8,3.6,2.5,and 1.7 MYA on the plateau during the late Cenozoic period. 展开更多
关键词 Panthera uncia Panthera pardus Panthera tigris MTDNA PHYLOGENY divergence time Qinghai-Tibetan Plateau
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Information schema constructs for instantiation and composition of system manifestation features
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作者 Shahab POURTALEBI Imre HORVATH 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第9期1396-1415,共20页
Complementing our previous publications, this paper presents the information schema constructs (ISCs) that underpin the programming of specific system manifestation feature (SMF) orientated information management ... Complementing our previous publications, this paper presents the information schema constructs (ISCs) that underpin the programming of specific system manifestation feature (SMF) orientated information management and composing system models. First, we briefly present (1) the general process of pre-embodiment design with SMFs, (2) the procedures of creating genotypes and phenotypes of SMFs, (3) the specific procedure of instantiation of phenotypes of SMFs, and (4) the procedure of system model management and processing. Then, the chunks of information needed for instantiation of phenotypes of SMFs are discussed, and the ISCs designed for instantiation presented. Afterwards, the information management aspects of system modeling are addressed. Methodologically, system modeling involves (1) placement of phenotypes of SMF in the modeling space, (2) combining them towards the desired architecture and operation, (3) assigning values to the parameters and checking the satisfac- tion of constraints, and (4) storing the system model in the SMFs-based warehouse database. The final objective of the reported research is to develop an SMFs-based toolbox to support modeling of cyber-physical systems (CPSs). 展开更多
关键词 System manifestation features (SMFs) Information schema constructs Database schemata SMF genotypes SMFphenotypes SMF instances Soft'ware tool box System-level design Cyber-physieal systems
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