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941.
上海市于1984年实施农作物新品种审定制度,至2006年共审(认)定新品种464个,包括粮食作物153个、油料作物24个、纤维作物5个、蔬菜134个、瓜果85个、食用菌31个。本文分析了上海市审定品种的物种多样性和主要作物的性状变异,并以水稻为例分析了水稻审定品种的多样性及育种成就,探讨了在水稻产量提高过程中的产量构成因子的作用。介绍了上海市审定品种数据化共享系统及其应用方法。  相似文献   
942.
Benjamin A. Bell 《Grana》2016,55(4):286-301
Thirty-three modern surface samples were collected in the environmentally and climatologically contrasting regions of the Middle and High Atlas Mountains, Morocco. Samples representing forest and steppe montane environments (1935–2760 m above sea level) are clustered around study sites at Lake Tislit (High Atlas, semi-arid oro-Mediterranean bioclime) and Lake Sidi Ali and Michliffen (Middle Atlas, sub-humid montane Mediterranean bioclime). Good discrimination between regional pollen spectra is evident, with Middle Atlas samples reflecting higher arboreal cover (Cedrus and evergreen Quercus) and High Atlas samples with high abundances of non-arboreal taxa, including Artemisia and Fabaceae. These four taxa (Cedrus, evergreen Quercus, Artemisia and Fabaceae) are furthermore shown to be reliable indicators of local source vegetation within a 100 m2 quadrat, taking into account threshold abundances of 7%, 20%, 4% and 10%, respectively. Deciduous Quercus, Olea and Phillyrea show long-distance pollen dispersal across both regions, contributing to non-trivial arboreal pollen (AP) values of up to 35% (typically 20–30%) in the High Atlas spectra. In the Middle Atlas, AP values of 40 to 50% occur in open sampling locations and > 60% under forest canopy cover. These insights should be taken into account when interpreting ancient pollen spectra from regional lakes and bogs for palaeoenvironmental reconstruction.  相似文献   
943.
The Mediterranean Basin is one of the most significantly altered World Biodiversity Hotspots with extensive habitat loss and fast genetic population erosion, for which urgent biodiversity reconnaissance and preservation actions are required. In particular, Sicily has about 600 taxa classified as threatened or near-threatened. The correct recognition and identification of such biodiversity is required for supporting further activities. The objective of this work is to assess the ability of the DNA barcoding approach to identify different taxonomic groups from a collection of the most threatened plant taxa, throughout natural Sicilian populations. The evaluation of the DNA barcoding core markers, rbcL and matK, was carried out on 30 taxa belonging to 13 families. DNA barcode fragments were recovered from all taxa (100%). The rbcL gene was recovered from 97% of the taxa and matK gene from 73%. In this test, 19 taxa overall (63%) were totally resolved at the specific or subspecific level, by at least one of the core markers. Fourteen of the 17 most threatened taxa (EN, CR) included in this work were totally discriminated. The matK and rbcL locus, respectively, resolved 64% and 48% of the taxa successfully sequenced. The matK gene expressed the highest genetic distance (K2P value), from 0.4% to 8.6%, against a range of 0.1–2% of rbcL gene. However, the rbcL gene appeared a good compromise between PCR, sequencing success and species-level resolution. Cryptic groups suggest the implementation of additional barcoding markers or different primer combinations, particularly for matK, in order to increase the performances. However, this preliminary result confirms the potential of the barcoding approach for quick identification of unknown and heterogeneous plant groups to generate a dedicated reference data-set of the threatened Sicilian flora for a wide range of applications.  相似文献   
944.
This paper summarizes present knowledge of the synanthropic nitrophilous communities dominated by tall herbs on the basis of the present Artemisietea vulgaris database. Floristic variability was examined also in detrended correspondence analysis. Each cluster was inspected for its ecological and floristic consistency. The final interpretable solution comprises five clusters. Species to clusters fidelity was calculated using ? coefficient. The ecological interpretation of the five groups was based on the average Pignatti indicator values. Groups were compared by using Tukey's honest significant difference test in conjunction with ANOVA. Finally, based on the statistical analysis, we established five alliances: Onopordionacanthii, Matricario-Chenopodion, Dauco-Melilotion, Arctionlappae, and Convolvuloarvensis-Elytrigionrepenti.  相似文献   
945.
African species of Oxyscelio (Hymenoptera: Platygastridae s.l.) are revised. A total of 14 species are recognized, 13 of which are described as new: Oxyscelio absentiae Burks, sp. n., Oxyscelio galeri Burks, sp. n., Oxyscelio gyri Burks, sp. n., Oxyscelio idoli Burks, sp. n., Oxyscelio intensionis Burks, sp. n., Oxyscelio io Burks, sp. n., Oxyscelio kylix Burks, sp. n., Oxyscelio lunae Burks, sp. n., Oxyscelio nemesis Burks, sp. n., Oxyscelio pulveris Burks, sp. n., Oxyscelio quassus Burks, sp. n., Oxyscelio teli Burks, sp. n. and Oxyscelio xenii Burks, sp. n. The genus Freniger Szabó, syn. n. is recognized as part of an endemic African species group of Oxyscelio with incomplete hind wing venation, and Oxyscelio bicolor (Szabó), comb. n. is therefore recognized as the only previously described species of Oxyscelio from Africa. The Oxyscelio crateris and Oxyscelio cuculli species groups, previously known from southeast Asia, are represented in Africa by seven and one species respectively.  相似文献   
946.
研究蛋白质和配体相互作用的结构和亲和力,不仅有助于了解蛋白质的功能,而且对药物研发以及药物作用机制的研究,也具有十 分重要的意义。目前,人们通过人工检索和半自动检索的方式,从文献和蛋白质数据库(Protein Data Bank,PDB)中获得了许多蛋白质- 配体亲和力信息和生物相关配体信息,并构建了许多蛋白质-配体相互作用的信息数据库。对3 个蛋白质-配体亲和力数据库和6 个蛋白质 晶体结构-配体生物相关性数据库进行介绍,并对其主要应用进行简述,希望能为实现高效准确地筛选和设计药物提供一定的帮助。  相似文献   
947.
蛋白质残基替换是基因突变的产物之一,它可能改变蛋白质三维结构,对其生物学功能产生重大影响,因此研究蛋白质残基替换与结构改变的关系具有重要意义.随着实验解析蛋白质结构的数量迅猛增长,越来越多的野生型-突变体被应用于结构生物学的比较研究中.本研究从蛋白质三维结构数据库(PDB)出发,收集和计算了大量结构特征数据,构建了一个目前已知最大的野生型-突变体(单残基差异)的结构对数据库DRSP,展示出氨基酸类型和主链偏好性对结构保守性的相关性.DRSP的开放使用可为高精度的蛋白质结构分析预测提供有用信息,它的数据库网址是http://www.labshare.cn/drsp/index.php.  相似文献   
948.
Atg8-family proteins are the best-studied proteins of the core autophagic machinery. They are essential for the elongation and closure of the phagophore into a proper autophagosome. Moreover, Atg8-family proteins are associated with the phagophore from the initiation of the autophagic process to, or just prior to, the fusion between autophagosomes with lysosomes. In addition to their implication in autophagosome biogenesis, they are crucial for selective autophagy through their ability to interact with selective autophagy receptor proteins necessary for the specific targeting of substrates for autophagic degradation. In the past few years it has been revealed that Atg8-interacting proteins include not only receptors but also components of the core autophagic machinery, proteins associated with vesicles and their transport, and specific proteins that are selectively degraded by autophagy. Atg8-interacting proteins contain a short linear LC3-interacting region/LC3 recognition sequence/Atg8-interacting motif (LIR/LRS/AIM) motif which is responsible for their interaction with Atg8-family proteins. These proteins are referred to as LIR-containing proteins (LIRCPs). So far, many experimental efforts have been carried out to identify new LIRCPs, leading to the characterization of some of them in the past 10 years. Given the need for the identification of LIRCPs in various organisms, we developed the iLIR database (https://ilir.warwick.ac.uk) as a freely available web resource, listing all the putative canonical LIRCPs identified in silico in the proteomes of 8 model organisms using the iLIR server, combined with a Gene Ontology (GO) term analysis. Additionally, a curated text-mining analysis of the literature permitted us to identify novel putative LICRPs in mammals that have not previously been associated with autophagy.  相似文献   
949.
The process of accurately gauging lifetime improvements in organic photovoltaics (OPVs) or other similar emerging technologies, such as perovskites solar cells is still a major challenge. The presented work is part of a larger effort of developing a worldwide database of lifetimes that can help establishing reference baselines of stability performance for OPVs and other emerging PV technologies, which can then be utilized for pass‐fail testing standards and predicting tools. The study constitutes scanning of literature articles related to stability data of OPVs, reported until mid‐2015 and collecting the reported data into a database. A generic lifetime marker is utilized for rating the stability of various reported devices. The collected data is combined with an earlier developed and reported database, which was based on articles reported until mid‐2013. The extended database is utilized for establishing the baselines of lifetime for OPVs tested under different conditions. The work also provides the recent progress in stability of unencapsulated OPVs with different architectures, as well as presents the updated diagram of the reported record lifetimes of OPVs. The presented work is another step forward towards the development of pass‐fail testing standards and lifetime prediction tools for emerging PV technologies.  相似文献   
950.
目的:通过分析GEO数据库结直肠癌相关芯片集,寻找差异基因,并在TCGA数据库和GEO数据库进行验证,为结直肠癌的早期诊断寻找标志物。方法:分析GEO数据库结直肠癌相关芯片集GSE21510、GSE25071、GSE32323。分别分析差异基因,采用文恩图软件查找共同差异基因。进一步在TCGA数据库查找差异基因在结直肠癌中的表达及生存曲线。最后通过GEO数据库GSE24514验证差异基因的表达。结果:GSE21510,包含104例样本,共筛选出251个差异基因,其中上调基因146个,下调基因105个。GSE25071,包含50例样本,共筛选出669个差异基因,其中上调基因312个,下调基因357个。GSE32323,包含10例样本,共筛选出353个差异基因,其中上调基因115个,下调基因238个。在样本中上调基因为促癌基因,下调基因为抑癌基因。经文恩图分析,3个基因集交集共有15个基因,其中上调基因3个,下调基因12个。在TCGA数据库中查找差异基因的表达量和生存曲线,生存曲线选择结肠癌数据集,选取279个样本进行分析。根据差异基因的表达和生存曲线,最终确定促癌基因INHBA和抑癌基因CLCA4、CA4为结直肠癌的标志物。最后在GSE24514芯片集验证差异基因的表达。结论:通过GEO和TCGA数据库筛选及验证,发现在结直肠癌组织中INHBA基因明显上调,CLCA4、CA4基因明显下调。最终确定促癌基因INHBA和抑癌基因CLCA4、CA4可作为结直肠癌早期诊断的标志物。  相似文献   
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