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The sequence of the 3'-terminal 1210 nucleotides of RNA 1 and the complete sequence of 3389 nucleotides of RNA 2 of tobacco rattle virus (TRV) strain TCM has been deduced. The sequence of the 3'-terminal 1099 nucleotides of RNAs 1 and 2 was found to be identical. Thus the genome of this TRV strain is partially diploid, encoding a 16K protein in both RNA 1 and RNA 2. The sequence that is unique to RNA 2 contains two open reading frames: the coat protein cistron and a cistron for a 29.1K protein, which shows no homology with the RNA 1 encoded 28.8K protein. cDNA probes corresponding to these two open reading frames cross-hybridized to pea early-browning virus RNA 2, but not to RNA 2 of five other tobraviruses tested.  相似文献   
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Abstract

The Westland petrel (Procellaria westlandica) is an endemic New Zealand species and one of the very few burrowing seabird species still breeding on mainland New Zealand. It nests only on a series of coastal ridgelines near to Punakaiki on the West Coast of the South Island. Between 2002 and 2005, surveys were undertaken at 28 of the 29 known colonies. The area occupied by the colonies was 73 ha; most colonies had fewer than 50 burrows, but six colonies had 201–500 burrows and four colonies had more than 1000 burrows. We find that the current breeding range of Westland petrel and the location of individual colonies are similar to those reported in both the 1950s and 1970s. Based on total burrow counts at 28 colonies and burrow occupancy rates determined by annual monitoring, the annual breeding population is estimated to be between 2954 and 5137 breeding pairs.  相似文献   
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Background

Patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) commonly require hospitalization and admission to intensive care unit (ICU). It is useful to identify patients at the time of admission who are likely to have poor outcome. This study was carried out to define the predictors of mortality in patients with acute exacerbation of COPD and to device a scoring system using the baseline physiological variables for prognosticating these patients.

Methods

Eighty-two patients with acute respiratory failure secondary to COPD admitted to medical ICU over a one-year period were included. Clinical and demographic profile at the time of admission to ICU including APACHE II score and Glasgow coma scale were recorded at the time of admission to ICU. In addition, acid base disorders, renal functions, liver functions and serum albumin, were recorded at the time of presentation. Primary outcome measure was hospital mortality.

Results

Invasive ventilation was required in 69 patients (84.1%). Fifty-two patients survived to hospital discharge (63.4%). APACHE II score at the time of admission to ICU {odds ratio (95 % CI): 1.32 (1.138–1.532); p < 0.001} and serum albumin (done within 24 hours of admission) {odds ratio (95 % CI): 0.114 (0.03-0.432); p = 0.001}. An equation, constructed using the adjusted odds ratio for the two parameters, had an area under the ROC curve of 91.3%. For the choice of cut-off, sensitivity, specificity, positive and negative predictive value for predicting outcome was 90%, 86.5%, 79.4% and 93.7%.

Conclusion

APACHE II score at admission and SA levels with in 24 hrs after admission are independent predictors of mortality for patients with COPD admitted to ICU. The equation derived from these two parameters is useful for predicting outcome of these patients.  相似文献   
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Protein–protein interactions are intrinsic to virtually every cellular process. Recent breakthroughs in techniques to study protein-interaction and the availability of fully sequenced plant genomes have attracted many plant scientists to undertake the first steps in the field of protein interactions. High-throughput screening systems allow the discovery of protein functions. Even without performing laborious functional assays, in planta functional homologues and redundant proteins can be accurately predicted based on protein-interaction maps. Therefore, protein–protein-interaction screenings are an essential supplement to the current functional-genomics toolbox.  相似文献   
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We have developed a novel strategy for the introduction of durable insect resistance in crops. This strategy was based on intervention in the natural relationship between plants and insects. For many insects, including pests such as thrips (Frankliniella occidentalis), the flower is an important factor in their life cycle, serving either as a food source or as a place for mating. The insects are attracted to the flower by scent, which is mainly produced by the petals, and by the bright colour of these floral organs. We therefore anticipated that removal or changing the identity of the petals would significantly reduce the attractiveness of the flower to thrips. To test this hypothesis, we used cucumber as a model species because most modern varieties are parthenocarpic, in which the fruit develops without fertilization. The cucumber mutant green petals, in which the petals are homeotically transformed into green sepals, was particularly useful for this study. The susceptibility of the cucumber plants to damage by thrips was determined by recording thrip numbers and by measuring leaf damage. Large differences were observed when greenhouse compartments with either wild-type or green petal mutant plants were compared. The rate of population growth of the insects on the mutant plants was significantly reduced and the leaves were almost undamaged. These results demonstrate that alterations in the structure of flowers may interfere with the life cycle of insects, providing the means for a novel and natural strategy for obtaining insect resistance.  相似文献   
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