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61.
A survey is given of 23 species of synathropic and synbovine Diptera collected in the years 1968, 1969 and 1972 in the Mongolian People's Republic by J. Minár. Besides the faunistical comments, the species of hygienic-epidemiological or public health importance are discussed. 相似文献
62.
G. Fraser W. W. Gregor C. P. Mackenzie J. S. A. Spreull A. R. Withers 《The Journal of small animal practice》1969,10(12):725-754
Abstract— —The authors describe briefly the anatomy and histology of the normal ear and the histopathological changes associated with otitis. The bacteria and fungi associated with infections of the ear are discussed. The incidence and results of treatment of otitis externa in out-patient and hospitalised cases are reported and the techniques and results of surgical procedures for conditions of the ear are detailed. 相似文献
63.
Andrew Whalen Gregor Gorjanc John M. Hickey 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(2):102-112
In this paper, we evaluate using genotype‐by‐sequencing (GBS) data to perform parentage assignment in lieu of traditional array data. The use of GBS data raises two issues: First, for low‐coverage (e.g., <2×) GBS data, it may not be possible to call the genotype at many loci, a critical first step for detecting opposing homozygous markers. Second, the amount of sequencing coverage may vary across individuals, making it challenging to directly compare the likelihood scores between putative parents. To address these issues, we extend the probabilistic framework of Huisman (Molecular Ecology Resources, 2017, 17, 1009) and evaluate putative parents by comparing their (potentially noisy) genotypes to a series of proposal distributions. These distributions describe the expected genotype probabilities for the relatives of an individual. We assign putative parents as a parent if they are classified as a parent (as opposed to e.g., an unrelated individual), and if the assignment score passes a threshold. We evaluated this method on simulated data and found that (a) high‐coverage (>2×) GBS data performs similarly to array data and requires only a small number of markers to correctly assign parents and (b) low‐coverage GBS data (as low as 0.1×) can also be used, provided that it is obtained across a large number of markers. When analysing the low‐coverage GBS data, we also found a high number of false positives if the true parent is not contained within the list of candidate parents, but that this false positive rate can be greatly reduced by hand tuning the assignment threshold. We provide this parentage assignment method as a standalone program called AlphaAssign. 相似文献
64.
Michael Willmann Emir Hadzijusufovic Olivier Hermine Mauro Dacasto Laura Marconato Karin Bauer Barbara Peter Susanne Gamperl Gregor Eisenwort Erika Jensen‐Jarolim Mathias Müller Michel Arock David M. Vail Peter Valent 《Veterinary and comparative oncology》2019,17(1):1-10
In humans, advanced mast cell (MC) neoplasms are rare malignancies with a poor prognosis. Only a few preclinical models are available, and current treatment options are limited. In dogs, MC neoplasms are the most frequent malignant skin tumours. Unlike low‐grade MC neoplasms, high‐grade MC disorders usually have a poor prognosis with short survival. In both species, neoplastic MCs display activating KIT mutations, which are considered to contribute to disease evolution. Therefore, tyrosine kinase inhibitors against KIT have been developed. Unfortunately, clinical responses are unpredictable and often transient, which remains a clinical challenge in both species. Therefore, current efforts focus on the development of new improved treatment strategies. The field of comparative oncology may assist in these efforts and accelerate human and canine research regarding diagnosis, prognostication, and novel therapies. In this article, we review the current status of comparative oncology approaches and perspectives in the field of MC neoplasms. 相似文献
65.
Gregor Plestenjak Klemen Eler Dominik Vodnik Mitja Ferlan Matja? ?ater Tja?a Kandu? Primo? Simon?i? Nives Ogrinc 《Journal of Soils and Sediments》2012,12(9):1327-1338
Purpose
The objective of this study is to estimate the contribution of various sources that influence soil CO2 concentrations in calcareous grassland.Materials and methods
The research was performed at the Podgorski Kras plain (45?°33?? N, 13?°55?? E, 400?C430?m.a.s.l.) in the sub-Mediterranean region of Slovenia (SW Slovenia), where many meadows and pastures have been abandoned. In parallel to the measurement of soil respiration R s, soil gas was sampled for stable isotope analysis. Samples were taken biweekly at two sites, Grassland and Invaded, from July 2008 until November 2010. In addition, daily variations in concentration and stable isotope composition of soil CO2 were determined in May 2009. The partitioning of soil CO2 concentrations was performed using stable isotope mass balance calculation.Results and discussion
The concentration and isotope composition of soil CO2 exhibited similar seasonal variations at both sites. Lower ??13CCO2 values, ranging from ?28.2 to ?15.2 ??, which occurred during warm periods and higher values, up to ?12.1 ??, were typical of cold winter periods, from December to March. Organic sources were estimated to constitute between 78 and 99?% of total soil CO2 during warmer periods from May until October. This contribution was lower during the winter, ranging from 46 to 77?%. In winter, the atmospheric component to soil CO2 dominated, constituting up to 60?%. On average, the inorganic contribution was estimated to comprise 12?% of the soil CO2 at all sampling locations. The contribution of this source to soil CO2 concentration, at up to 41?%, was highest in Grassland during the growing season. The inorganic source of soil CO2 was also an important component during daily variations. The highest contribution was observed during the day, in parallel to the highest respiration rates.Conclusions
The inorganic pool is shown to be an important part of soil CO2 in calcareous areas and should be considered as equal to organic CO2 as a source in soil CO2 partitioning. 相似文献66.
Rohn S Buchner N Driemel G Rauser M Kroh LW 《Journal of agricultural and food chemistry》2007,55(4):1568-1573
Flavonoids are an important constituent of the human diet. In recent years, they have gained much attention due to their physiological properties, leading to an enormous increase in research on cancer prevention and reduction of cardiovascular diseases. Unfortunately, there is limited information about the fate of flavonoid glycosides during thermal treatment such as cooking, frying, roasting, etc. Such processing techniques may have an impact on the flavonoid structure, resulting in changes of the bioavailability and activity of the flavonoids. In this study, the stability of selected model and onion quercetin glycosides under roasting conditions (180 degrees C) was determined. The influence of the kind and position of the sugar moiety was investigated. As onions contain large amounts of quercetin glycosides and are often subject to thermal processes in food production, their major glycosides were isolated using counter current chromatography and roasted. The thermal treatment led to a degradation of the quercetin glycosides. The main product is the aglycone quercetin, which remained stable during further roasting. During the roasting process of the quercetin diglucoside isolated from onion, the formation of a monoglycoside as an intermediate product was observed. This underlined that the stability of the glycosides is dependent on the kind and position of the sugar moiety. 相似文献
67.
68.
Site condition, fertility gradients and soil biological activity in a New Zealand frost-flat heathland 总被引:1,自引:0,他引:1
Gradients in stressed areas potentially provide a powerful tool to interpret relations between soil biodiversity and site quality. We measured soil chemistry, soil microbiology and nematodes along three transects representing a fertility gradient and at a disturbed site near a road in a Dracophyllum subulatum-dominated shrubland in which frosts are a major factor in preventing succession to forest; we used D. subulatum size as a site-quality index. Significant correlations between both shrub height and shrub growth rate and volumetric measures of total soil phosphorus and anaerobically mineralisable nitrogen indicate that nitrogen and phosphorus regulate plant growth. Microbial biomass and total nematode abundance significantly increased with greater plant growth, presumably in response to greater litter input. Conversely, neither heterotrophic microbial diversity nor nematode diversity was correlated with shrub performance along the transects. Litter was from a single species and thus likely similar in quality so changes in microbial or nematode diversity might not be expected. In this oligotrophic environment, nutrient levels were not only the important regulators of plant growth but also appeared to have an indirect influence on the size of the microbial and nematode populations. 相似文献
69.
H. D. Gregor 《Water, air, and soil pollution》1992,64(1-2):197-212
Among industrialized nations Germany ranks fourth in CO2 emissions. Most of these originate from the use of fossil fuels. Based on reports of a parliamentary study commission, established in 1987, and other expert groups in Germany this article adresses possible environmental effects of increasing atmospheric CO2, the sink potential of temperate forests and the influence of forest damage on this potential. A strategy for a 25 to 30% or 250 to 300×106 t yr?1 CO2 emissions reduction by 2005 (which Germany has itself committed to) is described in which measures to enhance C sequestration by forests play an important role. Expansion of forest area, a further increase of C storage by appropriate management and the restoration and protection of forest health impaired by air pollution would result in an additional storage of 17 to 20×106 t yr?1 of CO2, equaling 6 to 8% of the reduction target. 相似文献
70.
Shaw S Speare R Lynn DH Yeates G Zhao Z Berger L Jakob-Hoff R 《Journal of zoo and wildlife medicine》2011,42(3):473-479
Archey's frogs (Leiopelma archeyi) are first on the list of evolutionarily distinct and globally endangered (EDGE) amphibians. Captive breeding is an important strategy for protection of the species, but programs are hampered by a lack of information on diseases present in wild and captive populations. Two novel nematodes (Koerneria sp. and Rhabditis sp.) were found separately in four captive Archey's frogs showing clinical signs of hemorrhagic purulent nasal discharge and weight loss. One of these frogs also had a novel protozoal infection (Tetrahymena) in the nasal cavity. Koerneria, Rhabditis, and Tetrahymena have not previously been reported in amphibians in New Zealand. One frog was treated successfully with oral moxidectin at 0.4 mg/kg for the nematode infection and topical metronidazole at 10 mg/kg for the protozoal infection. The clinical signs abated only after both infections were cleared. The second frog died before treatment could be established. The third and fourth frogs were found dead. 相似文献