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81.
G K Smith D N Biery T P Gregor 《Journal of the American Veterinary Medical Association》1990,196(1):59-70
From mechanical principles and postmortem observations of coxofemoral joints of dogs, a hydrostatic mechanism influencing hip joint stability was discovered. This discovery led to the development of a stress-radiographic positioning method to quantitate hip joint laxity in dogs. The method incorporated 2 views with the dog in supine position and hips at neutral flexion/extension angle: a compression view, with the femoral heads fully seated in the acetabula; and a distraction view, with the femoral heads at maximal lateral displacement. An index measurement method was formulated to quantitate the relative degree of joint laxity appearing in either the compression or distraction view. Clinical evaluation of 6 dogs was done to compare the compression/distraction method with the standard hip-extended radiographic method. Also, the stress-radiographic method was performed on 16-week-old Borzoi and German Shepherd Dogs to compare the characteristics of inherent hip joint laxity in these breeds. In all dogs tested, hip joint laxity was masked by the standard hip-extended view as indicated by a 2.5-fold improvement in sensitivity to hip joint laxity of the new method (P less than 0.00001). Moreover, the mean hip joint laxity of 16-week-old German Shepherd Dogs exceeded the mean hip joint laxity of Borzois by 79% (P less than 0.00001). Reports in the literature document the incontrovertible association of hip joint laxity to the development of hip dysplasia in dogs. We believe the ability to accurately quantitate hip joint laxity will provide key diagnostic and prognostic criteria for the selection of pet dogs, and more importantly, breeding stock. 相似文献
82.
83.
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
84.
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
85.
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
86.
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
87.
Pinus radiata was planted in a grazed pasture at Tikitere, New Zealand in 1973; final tree stocking rates were 0, 50, 100, 200 and 400 stems
ha–1; trees were harvested in 1999. We sampled the loamy sand for chemistry, earthworms, enchytraeids and nematodes during crop
growth. There were no visible changes in the soil profile between years 2 and 25 of the P. radiata rotation, but marked changes in soil chemistry with pH declining at all depths. Topsoil pH declined but plant-available P
and the soil C : N ratio increased. That similar trends occurred in pasture may have reflected reduced inputs. Lumbricid earthworms
declined with increasing time and tree stocking rate; significant populations were found only in pasture at 25 years; no related
changes in soil bulk density were detected. Enchytraeids were abundant but declined in the plots with 200 and 400 stems ha–1. The composition of the nematode fauna at a soil depth of 0–10 cm varied, and there were changes in the “control” pasture.
Pratylenchus sp. and Pungentus sp. were characteristic of pasture;Diphtherophora sp. appeared at higher tree stocking rates. In addition to changes related to the change in landuse there were temporal changes
that affected faunal composition across tree stocking rates: Heterodera sp. and Paratylenchus sp. were rare after year 6;Prismatolaimus sp. was most abundant in years 2, 13 and 25;Axonchium sp. occurred in year 6 and Alaimus sp. mainly in year 25. Overall, the changes in soil chemistry reflected the change from pasture to forest. Parallel changes
in soil microfauna and macrofauna also reflected the change in landuse, from fertilised pasture to coniferous forest, and
are considered reversible.
Received: 5 July 1999 相似文献
88.
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89.
90.
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