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21.
To achieve the integration of biological data available on the World Wide Web and maintained in diverse sources such as GDB, Genbank or Acedb, we have developed a software called Jade. Jade allows programmers to create analytic tools and graphical user interfaces for one or more existing bioinformatics data sources. These tools can then be interchanged, compared and reused without making modifications in the data sources themselves. The system is implemented in the Java programming language and will run equally well on Macintosh, Windows or Unix workstations. Jade is free and can be used immediately by all interested parties.  相似文献   
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The great challenges for researchers working in the field of vaccinology are optimizing DNA vaccines for use in humans or large animals and creating effective single-dose vaccines using appropriated controlled delivery systems. Plasmid DNA encoding the heat-shock protein 65 (hsp65) (DNAhsp65) has been shown to induce protective and therapeutic immune responses in a murine model of tuberculosis (TB). Despite the success of naked DNAhsp65-based vaccine to protect mice against TB, it requires multiple doses of high amounts of DNA for effective immunization. In order to optimize this DNA vaccine and simplify the vaccination schedule, we coencapsulated DNAhsp65 and the adjuvant trehalose dimycolate (TDM) into biodegradable poly (DL-lactide-co-glycolide) (PLGA) microspheres for a single dose administration. Moreover, a single-shot prime-boost vaccine formulation based on a mixture of two different PLGA microspheres, presenting faster and slower release of, respectively, DNAhsp65 and the recombinant hsp65 protein was also developed. These formulations were tested in mice as well as in guinea pigs by comparison with the efficacy and toxicity induced by the naked DNA preparation or BCG. The single-shot prime-boost formulation clearly presented good efficacy and diminished lung pathology in both mice and guinea pigs.  相似文献   
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The Lower Cambrian Chengjiang fauna is reviewed and shown to be closely comparable with the younger Burgess Shale fauna. but with various differences in detail. A diverse group of more or less annulated lobopod animals including 'armoured lobopods' are regarded as representatives of the phylum Onychophora. 'Trilobitomorphs' include several new types. Probable protaspides of the trilobitomorph Naraoia are described. No molluses or deuterostomes have been identified. The preservational orientations of the various taxa are reviewed and compared with orientations of the Burgess Shale taxa. Orientation in the sediment is found to be closely correlated to the original shape of individuals. Several new genera and species are described: the segmented. worm-shaped Yunnanozoon lividum gen. et sp.n., the 'armoured lobopods' Onychodictyon ferox gen. et sp.n. and Cardiodictyon catenulum gen. et sp.n. and the arthropods Saperion glumaceum gen. et sp.n., Sinoburius Iunaris gen. et sp.n., and Xandarella spectaculum gen. et sp.n.  相似文献   
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Floral development of three Maesa Forssk. species, M. argenteaWall., M. japonica(Thunb.) Moritzi ex Zoll. and M. perlarius(Lour.)Merr., was studied with a scanning electron microscope. Thedistinctive floral features of the genus, such as presence oftwo persistent bracteoles, perigynous flowers and many-seededfruits, have been used to discuss the systematic position ofthe genus within Primulales. In addition, the development ofcommon stamen-petal primordia, the number, arrangement and positionof ovules and the shape of the anthers provide evidence in favourof placing Maesa in a separate family, Maesaceae, as suggestedby Anderberg and Ståhl (Canadian Journal of Botany, 73:1699–1730, 1995). Copyright 2000 Annals of Botany Company Primulales, Maesa argentea Wall., Maesa japonica(Thunb.) Moritzi ex Zoll., Maesa perlarius(Lour.) Merr., floral ontogeny, SEM  相似文献   
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The former Primulales used to be subdivided into the woody Theophrastaceae and Myrsinaceae, from the tropics and subtropics, and the herbaceous Primulaceae, which are mainly found in the temperate regions of the northern hemisphere. Recent analyses based on morphological as well as molecular data revealed a close relationship between the genus Samolus L. of Primulaceae and the monophyletic family Theophrastaceae. We studied the floral development of six species from four different genera of Theophrastaceae and compared it to floral ontogenetical data of Samolus valerandi L. to find support for a close relationship. Samolus and the members of Theophrastaceae share the presence of staminodes and a similar development of the placenta and the ovules. Apart from the different habit and distribution, however, we also observed some major differences between both lineages, such as the absence of common primordia in Theophrastaceae, the development of a gynoecial cap in Samolus, and the difference in development, shape, and structure of the staminodes. Therefore, we propose to keep Samolus separated from the genera of the Theophrastaceae, and we suggest that it be raised to family level.  相似文献   
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The distribution of aluminium (Al) accumulation in the Ericales is surveyed, based on semi-quantitative tests of 114 species and literature data. Al accumulation mainly characterises the families Diapensiaceae, Pentaphylacaceae, Symplocaceae, Ternstroemiaceae, and Theaceae. Al accumulation is consistently present or absent in most families examined, but the character appears to be more variable in a few taxa (e.g., Lecythidaceae, Myrsinaceae). Although the interfamilial relationships within the Ericales require further research, the ability to accumulate high levels of Al appears to show considerable taxonomic significance. While the majority of Al accumulating Ericales includes woody, tropical plants, the feature is remarkably present in several herbaceous Diapensiaceae, which have a distribution in cold to temperate areas. The association of different mycorrhizae types with plant roots is suggested to play a role in the exclusion of high Al levels from the shoot.  相似文献   
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 The influence of an arbuscular mycorrhizal (AM) fungus on phosphorus (P) and iron (Fe) uptake of peanut (Arachis hypogea L.) and sorghum (Sorghum bicolor L.) plants was studied in a pot experiment under controlled environmental conditions. The plants were grown for 10 weeks in pots containing sterilised calcareous soil with two levels of Fe supply. The soil was inoculated with rhizosphere microorganisms only or with rhizosphere microorganisms together with an AM fungus (Glomus mosseae [Nicol. & Gerd.] Gerdemann & Trappe). An additional small soil compartment accessible to hyphae but not roots was added to each pot after 6 weeks of plant growth. Radiolabelled P and Fe were supplied to the hyphae compartment 2 weeks after addition of this compartment. After a further 2 weeks, plants were harvested and shoots were analysed for radiolabelled elements. In both plant species, P uptake from the labelled soil increased significantly more in shoots of mycorrhizal plants than non-mycorrhizal plants, thus confirming the well-known activity of the fungus in P uptake. Mycorrhizal inoculation had no significant influence on the concentration of labelled Fe in shoots of peanut plants. In contrast, 59Fe increased in shoots of mycorrhizal sorghum plants. The uptake of Fe from labelled soil by sorghum was particularly high under conditions producing a low Fe nutritional status of the plants. These results are preliminary evidence that hyphae of an arbuscular mycorrhizal fungus can mobilise and/or take up Fe from soil and translocate it to the plant. Accepted: 6 March 1998  相似文献   
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