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31.
Ketogulonicigenium vulgare is characterized by the efficient production of 2KGA from L-sorbose. Ketogulonicigenium vulgare Y25 is known as a 2-keto-L-gulonic acid-producing strain in the vitamin C industry. Here we report the finished, annotated genome sequence of Ketogulonicigenium vulgare Y25.  相似文献   
32.
Yellow catfish has become one of the most important freshwater aquaculture species in China. The mono-sex male yellow catfish has important application value in aquaculture because the male grows generally faster than the sibling females under the same conditions. This study has screened YY super-male and YY physiological female yellow catfish by sex reversal, gynogenesis, and progeny testing, which can help to achieve the large-scale production of YY super-male and XY all-male. From 2008 to 2010, about 123,000 YY super-male were produced, and about 81 million XY all-male fry were produced with 100 % male rate by random sampling. Therefore, these results indicate that YY super-male and YY physiological female yellow catfish can be viable and fertile. We conclude that the mono-sex breeding technique by YY super-male yellow catfish is stable and reliable, which has great potential for application in yellow catfish aquaculture.  相似文献   
33.
The silkworm is a lepidopteran insect that has an open circulatory system with hemolymph consisting of blood and lymph fluid. Hemolymph is not only considered as a depository of nutrients and energy, but it also plays a key role in substance transportation, immunity response, and proteolysis. In this study, we used LC‐MS/MS to analyze the hemolymph proteins of four developmental stages during metamorphosis. A total of 728 proteins were identified from the hemolymph of the second day of wandering stage, first day of pupation, ninth day of pupation, and first day as an adult moth. GO annotations and categories showed that silkworm hemolymph proteins were enriched in carbohydrate metabolism, proteolysis, protein binding, and antibacterial humoral response. The levels of nutrient, immunity‐related, and structural proteins changed significantly during development and metamorphosis. Some, such as cuticle, odorant‐binding, and chemosensory proteins, showed stage‐specific expression in the hemolymph. In addition, the expression of several antimicrobial peptides exhibited their highest level of abundance in the hemolymph of the early pupal stage. These findings provide a comprehensive proteomic insight of the silkworm hemolymph and suggest additional molecular targets for studying insect metamorphosis.  相似文献   
34.
Microbial biosensors: a review   总被引:1,自引:0,他引:1  
Su L  Jia W  Hou C  Lei Y 《Biosensors & bioelectronics》2011,26(5):1788-1799
A microbial biosensor is an analytical device which integrates microorganism(s) with a physical transducer to generate a measurable signal proportional to the concentration of analytes. In recent years, a large number of microbial biosensors have been developed for environmental, food, and biomedical applications. Starting with the discussion of various sensing techniques commonly used in microbial biosensing, this review article concentrates on the summarization of the recent progress in the fabrication and application of microbial biosensors based on amperometry, potentiometry, conductometry, voltammetry, microbial fuel cell, fluorescence, bioluminescence, and colorimetry, respectively. Prospective strategies for the design of future microbial biosensors will also be discussed.  相似文献   
35.
Recombinant adeno-associated virus(rAAV) has proven to be a promising gene delivery vector for human gene therapy. However, its application has been limited by difficulty in obtaining enough quantities of high-titer vector stocks. In this paper, a novel and highly efficient production system for rAAV is described. A recombinant herpes simplex virus type 1(rHSV-1) designated HSV1-rc/△UL2, which expressed adeno-associated virus type2(AAV-2) Rep and Cap proteins, was constructed previously. The data confirmed that its functions were to support rAAV replication and packaging, and the generated rAAV was infectious. Meanwhile, an rAAV proviral cell line designated BHK/SG2, which carried the green fluorescent protein(GFP) gene expression cassette, was established by transfecting BHK-21 cells with rAAV vector plasmid pSNAV-2-GFP. Infecting BHK/SG2 with HSV1-rc/△UL2 at an MOI of 0.1 resulted in the optimal yields of rAAV, reaching 250 transducing unit(TU) or 4.28×104 particles per cell. Therefore, compared with the conventional transfection method, the yield of rAAV using this "one proviral cell line, one helper virus" strategy was increased by two orders of magnitude. Large-scale production of rAAV can be easily achieved using this strategy and might meet the demands for clinical trials of rAAV-mediated gene therapy.  相似文献   
36.
Y.T.Hou 《古生物学报》1955,(4):313-316
IntroductionThe materials which form the subject of the present paper were collectedfrom the following formations and localities:(1)The Middle Devonian Yukiangformation of Yungchun district and(2)The Devonian lenticular limestone ofLingchuan district of Kwangsi.The ostracods of the second locality are preservedas internal moulds and therefore are far from being complete.  相似文献   
37.
我国生物多样性保护与减贫协同发展模式探索   总被引:1,自引:0,他引:1  
生物多样性和贫困是全球关注的热点论题,生物多样性保护与减贫是关乎我国可持续发展、人民生活水平提高和2020年能否全面实现小康社会的重要问题。近年来,生态环境保护特别是生物多样性保护与贫困地区区域整体协调发展越来越受到社会各界的关注。本文对我国生物多样性保护与减贫的积极和消极影响关系进行了梳理和分析,采用态势分析法对我国现行的生物多样性保护与减贫的宏观政策在未来二者协同发展过程中的优势、劣势、机会和威胁进行了深入探讨。并在此基础上对以生物多样性可持续利用为核心的保护与减贫协调发展的途径进行了探索,提出了促进二者协同发展的生态移民、绿色资本带动、生态旅游、绿色考评等模式,以期对我国推进生物多样性保护与减贫协同发展提供借鉴。  相似文献   
38.
我们建立了测定间-α-胰蛋白酶抑制因子遗传表型的聚丙烯酰胺凝胶等电聚焦免疫固定技术,应用这种方法对居住在成都地区的汉族群体进行了群体研究和家系调查,结果表明中国汉族人群间-α-胰蛋白酶抑制因子具有遗传多态性,它有希望成为法医血液遗传学新的遗传标记。  相似文献   
39.
湖南永顺县落叶木莲资源考察研究   总被引:1,自引:0,他引:1  
首次报道湘西武陵山地永顺县发现国家一级保护植物落叶木莲。分布面积2000 hm2,多呈散生分布,稀有小面积群落,成年大树有5000余株,胸径5 cm以下幼树及小苗有20000余株。落叶木莲群落属常绿与落叶阔叶混交林,分布海拔400~900 m的山坡中下部,主要有枫香、野漆树、落叶木莲和甜槠、星毛石栎、落叶木莲等群落类型。此前,落叶木莲仅分布江西幕阜山地宜春市明月山,是木兰科木莲属极度濒危的唯一一个落叶树种,对探讨被子植物的起源和木兰科的系统演化有重要的科学意义。  相似文献   
40.
从中国发病鸡中分离的鸡减蛋综合征病毒(EggDropSyndromVirus,EDSV)弱毒株(AA-2),其基因组全长约为33kb。用限制性内切酶HindⅢ水解EDSV全基因组,构建了以pBluescriptⅡ(KS+)为载体的右末端片段的克隆(约4.2kb),对其进行了序列测定和结构分析。该片段全长4183个碱基对(bp),位于基因组右末端87.3m.u.-100m.u.。结果显示,该片段与哺乳动物腺病毒右末端E4区结构不同,与禽Ⅰ型腺病毒代表株CELO右末端片段亦无同源性。本文为深入了解EDSV基因组结构特点,EDSV与其他腺病毒基因结构与功能的进化关系和EDSV载体的构建奠定了分子生物学基础  相似文献   
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