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1.
Conservation management of the Tasmanian flora is now focusing on non-vascular plants. Major problems include the low level of information on the composition of the flora and the low number of competent specialists available to deal with the plants. Collation of information from literature and from collections in herbaria is required to establish exactly which data are available and their reliability. An environmental domain analysis covering all ecosystems would indicate which environments were under-represented or absent from current reserves and where needs for conservation lie. Within practical time-frames, this process is probably the best method of capturing unknown components of the flora whilst also catering for widespread species and those closely associated with particular environments. It also incorporates regional variability. Minor habitats, which are often floristically rich, and very rare species are best dealt with on an individual basis. Basic research into taxonomy and ecology is paramount. Reservation and conservation management must be based on well-established and maintained databases which are in turn based on a coherent taxonomy and sound biogoographical information. It is only by pursuing an active research programme that the necessary accurate information can be obtained and the success of the management procedures can be gauged. 相似文献
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Information regarding all consultations was collected in seven general practices for one year. From these data we report on the use of laboratory tests and its association with patient characteristics--including social class, age, sex, and diagnosis--and with which doctor was consulted. Most of the requests were for technically simple tests of low cost. There was a noticeable variation in the use of tests with regard to all patient characteristics. Diagnosis, identity of doctor, age of patient, and social class were each shown by multivariate techniques to be independently related to use of tests. Whereas fewer tests were used per consultation for social classes III-V compared with other social classes, more were used per patient per year for these same groups, reflecting in part the higher consultation rates of social classes III-V. Variation in diagnoses fully accounted for the greater test ordering for women. Nearly two thirds of all tests were ordered for 10% of all patients who consulted and 7% of all registered patients. The results of our analysis suggest that this concentration is determined primarily by those patient characteristics most indicative of medical need and by which doctor is providing care. 相似文献
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Ronald Jarman 《BMJ (Clinical research ed.)》1934,1(3826):796-799
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Maia A. Rabaa Chonticha Klungthong In-Kyu Yoon Edward C. Holmes Piyawan Chinnawirotpisan Butsaya Thaisomboonsuk Anon Srikiatkhachorn Alan L. Rothman Darunee Tannitisupawong Jared Aldstadt Ananda Nisalak Mammen P. Mammen Robert V. Gibbons Timothy P. Endy Thanyalak Fansiri Thomas W. Scott Richard G. Jarman 《PLoS neglected tropical diseases》2013,7(1)
Revealing the patterns and determinants of the spread of dengue virus (DENV) at local scales is central to understanding the epidemiology and evolution of this major human pathogen. We performed a phylogenetic analysis of the envelope (E) genes of DENV-1, -2, -3, and -4 isolates (involving 97, 23, 5, and 74 newly collected sequences, respectively) sampled from school-based cohort and village-based cluster studies in Kamphaeng Phet, Thailand, between 2004 and 2007. With these data, we sought to describe the spatial and temporal patterns of DENV spread within a rural population where a future vaccine efficacy trial is planned. Our analysis revealed considerable genetic diversity within the study population, with multiple lineages within each serotype circulating for various lengths of time during the study period. These results suggest that DENV is frequently introduced into both semi-urban and rural areas in Kamphaeng Phet from other populations. In contrast, the persistence of viral lineages across sampling years was observed less frequently. Analysis of phylogenetic clustering indicated that DENV transmission was highly spatially and temporally focal, and that it occurred in homes rather than at school. Overall, the strength of temporal clustering suggests that seasonal bottlenecks in local DENV populations facilitate the invasion and establishment of viruses from outside of the study area, in turn reducing the extent of lineage persistence. 相似文献
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Polyana C Tizioto Jeremy F Taylor Jared E Decker Caio F Gromboni Mauricio A Mudadu Robert D Schnabel Luiz L Coutinho Gerson B Mour?o Priscila SN Oliveira Marcela M Souza James M Reecy Renata T Nassu Flavia A Bressani Patricia Tholon Tad S Sonstegard Mauricio M Alencar Rymer R Tullio Ana RA Nogueira Luciana CA Regitano 《遗传、选种与进化》2015,47(1)
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Taweewun Hunsawong Panya Sunintaboon Saradee Warit Butsaya Thaisomboonsuk Richard G. Jarman In-Kyu Yoon Sukathida Ubol Stefan Fernandez 《PLoS neglected tropical diseases》2015,9(9)
Dengue viruses (DENVs) are among the most rapidly and efficiently spreading arboviruses. WHO recently estimated that about half of the world’s population is now at risk for DENV infection. There is no specific treatment or vaccine available to treat or prevent DENV infections. Here, we report the development of a novel dengue nanovaccine (DNV) composed of UV-inactivated DENV-2 (UVI-DENV) and Mycobacterium bovis Bacillus Calmette-Guerin cell wall components (BCG-CWCs) loaded into chitosan nanoparticles (CS-NPs). CS-NPs were prepared by an emulsion polymerization method prior to loading of the BCG-CWCs and UVI-DENV components. Using a scanning electron microscope and a zetasizer, DNV was determined to be of spherical shape with a diameter of 372.0 ± 11.2 nm in average and cationic surface properties. The loading efficacies of BCG-CWCs and UVI-DENV into the CS-NPs and BCG-CS-NPs were up to 97.2 and 98.4%, respectively. THP-1 cellular uptake of UVI-DENV present in the DNV was higher than soluble UVI-DENV alone. DNV stimulation of immature dendritic cells (iDCs) resulted in a significantly higher expression of DCs maturation markers (CD80, CD86 and HLA-DR) and induction of various cytokine and chemokine productions than in UVI-DENV-treated iDCs, suggesting a potential use of BCG- CS-NPs as adjuvant and delivery system for dengue vaccines. 相似文献
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The aim of this study was to determine the first effect of lead on microbial activity in soil. The study was carried out in the soil samples from four different radish (Raphanus sativus L. var. radicula, Brassicaceae) fields along the highway in a district (Kadirli, Osmaniye) of the Eastern Mediterranean Region, Turkey. After the calculation of Pb contents, the Pb amounts of the soil samples were brought up to 50 and 100 mg Pb kg?1 by treatment with Pb(NO 3 ) 2 , and the samples for the carbon and the nitrogen mineralization were incubated under controlled conditions (28°C, constant moist). The carbon mineralization was determined by a CO 2 respiration method for 30 days. The nitrogen mineralization was observed in vitro for 6 weeks. The untreated group was statistically different from the 50 and 100 mg Pb kg?1 treatments in the aspect of the C(CO 2 ) outlet during mineralization (P ≤ 0.05), but difference between the 50 and 100 mg Pb kg?1 treatments was not significant. NH 4 -N and NO 3 -N contents of each soil were shown differences between across treatments. Based on these results, it is possible to conclude that the addition of 50 and 100 mg Pb kg?1 provided a toxic effect threshold for the microbial activity into 30 days. 相似文献