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61.
PRACTICAL RELEVANCE: Cats commonly present with pelvic trauma following road traffic accidents (RTAs). A logical step-wise approach to diagnostics and subsequent management can significantly improve the prognosis in the majority of cases. This article provides a practical guide to assist decision-making and optimise management of these cats. CLINICAL CHALLENGES: Affected cats may have sustained trauma to several body systems and, hence, their management can be complex, requiring good clinical, diagnostic and surgical skills (often both soft tissue and orthopaedic!). PATIENT GROUP: Any cat allowed access to the outdoors is potentially at risk of being involved in an RTA and sustaining pelvic trauma. Young male cats are most commonly affected. EVIDENCE BASE: Many original articles and textbook chapters have been published on aspects of pelvic trauma. However, to the authors' knowledge, this is the first comprehensive overview of the assessment and management of the feline pelvic trauma case. The review begins by discussing initial triage and neurological examination, and then focuses, in turn, on assessment and management of the 'tail pull' injury, the diagnosis and management of urinary tract rupture, and the approach to managing specific pelvic fractures.  相似文献   
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Background

Efficient high throughput screening systems of useful mutants are prerequisite for study of plant functional genomics and lots of application fields. Advance in such screening tools, thanks to the development of analytic instruments. Direct analysis in real-time (DART)-mass spectrometry (MS) by ionization of complex materials at atmospheric pressure is a rapid, simple, high-resolution analytical technique. Here we describe a rapid, simple method for the genetic discrimination of intact Arabidopsis thaliana mutant seeds using metabolic profiling by DART-MS.

Results

To determine whether this DART-MS combined by multivariate analysis can perform genetic discrimination based on global metabolic profiling, intact Arabidopsis thaliana mutant seeds were subjected to DART-MS without any sample preparation. Partial least squares-discriminant analysis (PLS-DA) of DART-MS spectral data from intact seeds classified 14 different lines of seeds into two distinct groups: Columbia (Col-0) and Landsberg erecta (Ler) ecotype backgrounds. A hierarchical dendrogram based on partial least squares-discriminant analysis (PLS-DA) subdivided the Col-0 ecotype into two groups: mutant lines harboring defects in the phenylpropanoid biosynthetic pathway and mutants without these defects. These results indicated that metabolic profiling with DART-MS could discriminate intact Arabidopsis seeds at least ecotype level and metabolic pathway level within same ecotype.

Conclusion

The described DART-MS combined by multivariate analysis allows for rapid screening and metabolic characterization of lots of Arabidopsis mutant seeds without complex metabolic preparation steps. Moreover, potential novel metabolic markers can be detected and used to clarify the genetic relationship between Arabidopsis cultivars. Furthermore this technique can be applied to predict the novel gene function of metabolic mutants regardless of morphological phenotypes.  相似文献   
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BACKGROUND: The tomato leafminer (Tuta absoluta Povolny) has rapidly colonised the whole Mediterranean and South‐Atlantic coasts of Spain, and it has become a key problem in both outdoor and greenhouse crops. New control methods compatible with biological control are required, and mating disruption appears to be a perfect method in current agriculture, as it is an environmentally friendly and residue‐free technique. IPM packages tested have included the use of pheromones to detect populations, but there has not been much previous research on mating disruption of T. absoluta. In this work, pheromone doses varying from 10 to 40 g ha?1, emitted at a constant rate over 4 months, were tested in greenhouses with different levels of containment in order to evaluate the efficacy of mating disruption on T. absoluta. RESULTS: Trials on containment level revealed that the flight of T. absoluta was satisfactorily disrupted with an initial pheromone dose of 30 g ha?1, and levels of damage did not significantly differ from those in reference plots with insecticide treatments. Later efficacy trials confirmed previous experiences, and release studies showed that control of damage and flight disruption were taking place when releasing at least 85 mg pheromone per ha per day. CONCLUSION: Effective control using pheromone application against T. absoluta can be achieved, in greenhouses with high containment levels, for 4 months, with initial doses of 30 g ha?1. Further research must be conducted in order to evaluate the prospect of outdoor application of mating disruption systems. Copyright © 2011 Society of Chemical Industry  相似文献   
66.
Heavy metal phytoextraction is a soil remediation technique, which makes use of plants in removing contamination from soil. The plants must thus be tolerant to heavy metals, adaptable to soil and climate characteristics, and able to take up large amounts of heavy metals. Most of the high biomass productive plants such as, maize, oat and sunflower are plants, which do not grow in cold climates or need intensive care. In this study three “weed” plants, Borago officinalis; Sinapis alba L. and Phacelia boratus were investigated for their ability to tolerate and accumulate high amounts of Cd and Pb. Pot experiments were performed with soil containing Cd and Pb at concentrations of up to 180 mg kg?1 and 2,400 mg kg?1 respectively. All three plants showed high levels of tolerance. Borago officinalis; and Sinapis alba L. accumulated 109 mg kg?1 and 123 mg kg?1 Cd, respectively at the highest Cd spiked soil concentration. Phacelia boratus reached a Cd concentration of 42 mg kg?1 at a Cd soil concentration of 100 mg kg?1. In the case of Pb, B. officinalis and S. alba L. displayed Pb concentrations of 25 mg kg?1 and 29 mg kg?1, respectively at the highest Pb spiked soil concentration. Although the Pb uptake in P. boratus reached up to 57 mg kg?1 at a Pb spiked soil concentration of 1,200 mg kg?1, it is not suitable for phytoextraction because of its too low biomass.  相似文献   
67.
Female Safari cats are offspring of domestic and Geoffroy parents, and are balanced heterozygotes with equal numbers of Blood cells containing domestic and Geoffroy-type glucose 6-phosphate dehydrogenase (G6PD),an X-chromosome derived enzyme. In previous studies, however, we observed increasing percentages of Blood cells with Geoffroy G6PD in cats aged 4–12 years. Similarly, ratios of parental X-chromosome phenotypes greater than three to one are common in women over age 60, while women under 40 typically exhibit one to one ratios. Using a two-compartment hidden-Markov model of the distribution of phenotype in samples taken during the second stage of hematopoiesis (Blood cell production), we estimate, through simulation and mathematical calculation, the Geoffroy selective advantages necessary to reproduce the data obtained from female Safari cats. It is shown that small differences in the kinetics of hematopoietic stem cells (HSC), less than might be detected by in vitro assays, can explain the “clonal dominance” observed with aging in cats, and by extension, human females. Conceptually, hematopoiesis in females can be viewed as a competitive exclusion process in which two populations of HSC (defined by parental X-chromosome phenotype) compete for environmental resources. As in many ecological examples, dominance may occur only after long periods of time.  相似文献   
68.
A fast-response and interference-free amperometric biosensor based on choline oxidase immobilized onto an electropolymerized polypyrrole film for flow injection determination of choline in milk, milk powder, and soy lecithin hydrolysates is described. The sensor displayed an Imax value of 1.9 +/- 0.2 microA and an apparent Michaelis-Menten constant, k'M, equal to 1.75 +/- 0.07 mM. Detection limits of 0.12 microM could be obtained. Because even a slight deterioration of the anti-interference membrane can adversely affect measurement accuracy, a real time monitoring of the biosensor selectivity has been achieved by a dual Pt electrode flow-through cell where the enzyme modified electrode is coupled to an enzyme-free electrode in a parallel configuration. Finally, bracketing technique (alternate injections of sample and standards) allows a two-point calibration to be performed in real-time, correcting for any drift in sensor response.  相似文献   
69.
Purpose

The application of sludge from wastewater in agriculture has increased in recent years, and it is therefore important to assess the effect that such treatment has on both the soil and the plant. The aim of the study described here was to ascertain whether there is a variation in the properties of the soil and to determine if this addition has an impact on the plant.

Materials and methods

The area of investigation was close to the municipality of Villarrubia de los Ojos (Ciudad Real). In this work, six samples were taken from the surface horizon in the studied plot at a depth of 35 cm. A further three samples were taken: (i) a surface horizon of a soil close to the area under investigation but without treatment (control sample), (ii) a sample of sludge from the wastewater treatment plant and (iii) a sample of the mixture used by farmers as fertilizer. Laboratory tests were conducted in accordance with the SCS-USDA (1972) guidelines. Trace element samples were analysed by X-ray fluorescence spectrophotometry (Philips PW 2404).

Results and discussion

The parcel of land studied is dominated by a sandy texture (88.3 % sand), and a decrease in pH was observed in areas in which the mixture (manure + sludge) was added (pH?=?8.0) compared to areas in which fertilizer was not applied (pH?=?8.5). It was observed that the addition of the compound led to an increase in the electrical conductivity of the soil. The trace elements can be organized into two groups based on the results obtained in this study. One group contains the trace elements that were only present in the rows that were treated with the fertilizer. The other group of trace elements was mobilized throughout the whole plot.

Conclusions

The application of sewage sludge on agricultural soils can be very useful as an organic amendment because it produces an increase in soil organic matter. However, sewage sludge must be applied with caution due to the changes in soil chemical properties (for example, pH and E.C.). The use of this type of waste for prolonged periods of time can cause problems of contamination in the soil.

  相似文献   
70.
The composition of melanoidins formed in the reactions of either glucose or maltose with glycine (70 degrees C, pH 5.5, [glucose] = [maltose] = [glycine] = 0.25 M) (MW > 3500) was investigated by microanalysis and the use of (14)C-labeled sugars and amino acid. The most reliable parameter obtained from microanalysis data is the C/N value, as it was calculated with no model assumption. The C/N value (7.6 +/- 0.2 for glucose and 10.5 +/- 0.2 for maltose) does not change with molecular weight (MW > 3500) as the polymers grow in size. A comparison between the radiochemically determined composition and that obtained from microanalysis suggests that the amino ketone, which is one of the products of Strecker degradation reaction, forms part of the of the melanoidin structure, together with the sugar-derived moiety and the Strecker aldehyde. Evidence is presented that glucose is formed at intermediate stages of the maltose-glycine reaction. The melanoidins are the result of the polymerization of glucose and intact, or substantially intact, maltose residues with glycine.  相似文献   
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