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81.
根据生态经济型防护林体系及其建设模式的内涵,研制开发出了以专家为核心,包括数据及数据库、图形及图形库、模型及模型库等模块的智能决策支持系统,以便为给定区域提供有关生态经济型防护林体系建设方面的决策服务。  相似文献   
82.

Background  

The nontoxigenic V. cholerae El Tor strains ferment sorbitol faster than the toxigenic strains, hence fast-fermenting and slow-fermenting strains are defined by sorbitol fermentation test. This test has been used for more than 40 years in cholera surveillance and strain analysis in China. Understanding of the mechanisms of sorbitol metabolism of the toxigenic and nontoxigenic strains may help to explore the genome and metabolism divergence in these strains. Here we used comparative proteomic analysis to find the proteins which may be involved in such metabolic difference.  相似文献   
83.
Gao T  Wu Y  Zhang Y  Liu L  Ning Y  Wang D  Tong H  Chen S  Chu C  Xie Q 《Plant molecular biology》2011,76(1-2):145-156
Recent genomic and genetic analyses based on Arabidopsis suggest that ubiquitination plays crucial roles in the plant response to abiotic stress and the phytohormone abscisic acid (ABA). However, few such studies have been reported in rice as a monocotyledonous model plant. Taking advantage of strategies in biochemistry, molecular cell biology and genetics, the RING-finger containing E3 ligase OsSDIR1 (Oryza sativa SALT-AND DROUGHT-INDUCED RING FINGER 1) was found to be a candidate drought tolerance gene for engineering of crop plants. The expression of OsSDIR1 was detected in all tissues of rice and up-regulated by drought and NaCl, but not by ABA. In vitro ubiquitination assays demonstrated that OsSDIR1 is a functional E3 ubiquitin ligase and that the RING finger region is required for its activity. OsSDIR1 could complement the drought sensitive phenotype of the sdir1 mutant and overexpressing transgenic Arabidopsis were more sensitive to ABA, indicating that the OsSDIR1 gene is a functional ortholog of SDIR1. Upon drought treatment, the OsSDIR1-transgenic rice showed strong drought tolerance compared to control plants. Analysis of the stomata aperture revealed that there were more closed stomatal pores in transgenic plants than those of control plants. This result was also confirmed by the water loss assay and leaf related water content (RWC) measurements during drought treatment. Thus, we demonstrated that monocot- and dicot- SDIR1s are conserved yet have diverse functions.  相似文献   
84.

Background

An influenza H3N2 epidemic occurred throughout Southern China in 2012.

Methods

We analyzed the hemagglutinin (HA) and neuraminidase (NA) genes of influenza H3N2 strains isolated between 2011–2012 from Guangdong. Mutation sites, evolutionary selection, antigenic sites, and N-glycosylation within these strains were analyzed.

Results

The 2011–2012 Guangdong strains contained the HA-A214S, HA-V239I, HA-N328S, NA-L81P, and NA-D93G mutations, similar to those seen in the A/ Perth/16/2009 influenza strain. The HA-NSS061–063 and NNS160–162 glycosylation sites were prevalent among the 2011–2012 Guangdong strains but the NA-NRS402–404 site was deleted. Antigenically, there was a four-fold difference between A/Perth/16/2009 -like strains and the 2011–2012 Guangdong strains.

Conclusion

Antigenic drift of the H3N2 subtype contributed to the occurrence of the Southern China influenza epidemic of 2012.
  相似文献   
85.
Huang  Zhi  Lian  Yajun  Chen  Yuan  Li  Shuang  Zhang  Haifeng  Xie  Nanchang  Zheng  Yake  Wu  Shouyi  Wang  Yuhan  Cheng  Wenchao  Zhang  Qiaoman  Wang  Chengze  Shi  Yinping  Xie  Na 《Neurochemical research》2019,44(5):1262-1268
Neurochemical Research - Botulinum neurotoxins (BoNTs) block the release of a series of neurotransmitters, which are pivotal for neuron action. Intrahippocampal administration of BoNTs inhibits...  相似文献   
86.
Through mRNA extract, RT and a series of PCR, phage antibody libraries were constructed from rP27kip 1-immunized and non-immunized mice. After only one round of selection with rP27kip 1, clones from each library were chosen randomly and digested byTag I and Hinf I. 11 of 64 clones from the immunized animal had consistent restriction pattern, while none of the 64 clones from the non-immunized animal had, except that one had the same fragments pattern as that of the 11 clones. The 12 fragments were expressed inE. coli BL21(DE3)/pET-28b(+) system. ELISA showed that some of the fragments could bind to rP27kip 1 specifically. AU these results implied that specific antibody can be obtained by genetic engineering without hybridoma or many rounds of growth and panning selection.  相似文献   
87.
渗透胁迫是指由于环境因素的变化使植物不能得到充足水分的一种状况。常见的渗透胁迫因素有干旱、盐害及冻害等。渗透胁迫会严重影响植物的生长发育及产量。植物在长期的进化过程中形成了一些保护机制能减轻渗透胁迫造成的伤害。比如有些植物在形态上演化生成盐腺,能排出体内的过量盐分以逃避盐害。但在渗透胁迫下几乎所有的植物都能合成一些无毒性的小分子有机物作为渗透调节剂来维持细胞内渗透势的相对稳定。在分子水平上...  相似文献   
88.
The ITS-Is of 24 accessions belong to 10 species of subgenusGlycine, and 2 species of subgenusSoja of genusGlycine were amplified, cloned and sequenced. According to the homology of the sequences, the phylogeny of the 24 accessions were reconstructed. The reconstructed dendrogram showed that there were some divergent genomic types found in the previously classified species, such asG. tomentella, G. canescens andG. tabacina, and they might be some cryptic species by morphologic analysis. Project supported by the Chinese Academy of Sciences  相似文献   
89.
DNA分子标记、基因组作图及其在植物遗传育种上的应用   总被引:45,自引:0,他引:45  
本文总结了现代分子生物学所发展的各类分子标记及其在遗传图谱构建中的作用,还综述了遗传图谱与物理图谱的构建、数量与质量性状定位及分子标记在作物育种中的应用。  相似文献   
90.
This study was designed to reveal the genome‐wide distribution of presence/absence variation (PAV) and to establish a database of polymorphic PAV markers in soybean. The 33 soybean whole‐genome sequences were compared to each other with that of Williams 82 as a reference genome. A total of 33,127 PAVs were detected and 28,912 PAV markers with their primer sequences were designed as the database NJAUSoyPAV_1.0. The PAVs scattered on whole genome while only 518 (1.8%) overlapped with simple sequence repeats (SSRs) in BARCSOYSSR_1.0 database. In a random sample of 800 PAVs, 713 (89.13%) showed polymorphism among the 12 differential genotypes. Using 126 PAVs and 108 SSRs to test a Chinese soybean germplasm collection composed of 828 Glycine soja Sieb. et Zucc. and Glycine max (L.) Merr. accessions, the per locus allele number and its variation appeared less in PAVs than in SSRs. The distinctness among alleles/bands of PCR (polymerase chain reaction) products showed better in PAVs than in SSRs, potential in accurate marker‐assisted allele selection. The association mapping results showed SSR + PAV was more powerful than any single marker systems. The NJAUSoyPAV_1.0 database has enriched the source of PCR markers, and may fit the materials with a range of per locus allele numbers, if jointly used with SSR markers.  相似文献   
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