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11.
Joanna Lodzinska Hannah Leigh Magdalena Parys Tiziana Liuti 《Veterinary radiology & ultrasound》2019,60(6):745-752
Peripheral vein phlebitis (inflammation) is a relatively frequent complication in dogs, however, published information on the ultrasonographic characteristics is currently lacking. This prospective, observational study describes the ultrasound (US) characteristics of normal canine cephalic veins, and veins with clinical phlebitis. Correlations among US findings and between US findings versus time that the intravenous catheter was in place were investigated. Safety of the US procedure was evaluated. Fifty patients were prospectively recruited for the study and 18 met the final inclusion criteria. Each patient underwent daily US examinations and was assessed for multiple criteria (vascular wall appearance, compressibility, spontaneity of flow, color fill, and presence/absence of filling defects, flow contour, direction, non‐pulsatility). Characteristics of normal canine cephalic veins were as follows: smooth and thin wall, complete compressibility, no flow disturbances, no filling defects, smooth flow contours, and unidirectional, non‐pulsatile flow with no turbulence. Characteristics of cephalic veins with clinical phlebitis were as follows: wall thickening (83%), decreased compressibility (55%), filling defects consistent with intraluminal thrombus (55%), vessel wall hyperechogenicity (44%), and abnormal color Doppler flow (39%). Significant correlations were found between Doppler filling defects and compressibility, Doppler filling defects and presumed thrombosis, and compressibility and presumed thrombosis (P = .001, P = .001, P = .000, respectively). No correlation was found between the US findings and time the intravenous catheter was in place. Findings indicated that duplex and compressibility US are feasible and safe methods for characterizing and monitoring cephalic veins in dogs with clinical phlebitis. 相似文献
12.
13.
Hannah J. Munro Lesley Berghuis Andrew S. Lang Laura Rogers Hugh Whitney 《Canadian journal of veterinary research》2014,78(2):140-144
Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are retroviruses found within domestic and wild cat populations. These viruses cause severe illnesses that eventually lead to death. Housing cats communally for long periods of time makes shelters at high risk for virus transmission among cats. We tested 548 cats from 5 different sites across the island of Newfoundland for FIV and FeLV. The overall seroprevalence was 2.2% and 6.2% for FIV and FeLV, respectively. Two sites had significantly higher seroprevalence of FeLV infection than the other 3 sites. Analysis of sequences from the FeLV env gene (envelope gene) from 6 positive cats showed that 4 fell within the FeLV subtype-A, while 2 sequences were most closely related to FeLV subtype-B and endogenous feline leukemia virus (en FeLV). Varying seroprevalence and the variation in sequences at different sites demonstrate that some shelters are at greater risk of FeLV infections and recombination can occur at sites of high seroprevalence. 相似文献
14.
Structured lipids (SLs) are triacylglycerols that have been modified to change the fatty acid composition and/or positional distribution in the glycerol backbone by chemically and/or enzymatically catalyzed reactions and/or genetic engineering. Ten percent oil-in-water emulsions were formulated with a canola oil/caprylic acid SL and stabilized with 0.5% whey protein isolate (WPI) or sucrose fatty acid ester (SFE). The effects of alpha-tocopherol, beta-carotene, genistein, and daidzein (added at 0.02 wt % of oil) on lipid oxidation were evaluated over a 15-day period in emulsion samples. Significantly (p < 0.05) less total oxidation (calculated from peroxide value and anisidine value measurements) occurred in the WPI emulsions compared to their SFE counterparts. In this study, alpha-tocopherol, beta-carotene, and both soy isoflavones exhibited prooxidant activities in SFE emulsions. Because of their ability to exhibit prooxidant activity under certain conditions, manufacturers must experiment with these compounds before adding them to SL-based products as functional ingredients. 相似文献
15.
Hannah Scott Marcella Fernandes de Souza Erik Meers Naomi Laura Jane Rintoul-Hynes 《植物养料与土壤学杂志》2023,186(4):387-396
Background
Roadside grass cuttings are currently considered a waste product due to their association with road sweepings as contaminated waste, therefore, their potential as a biofertilizer is understudied.Aim
This study aimed to determine whether grass liquid fraction (GLF) collected from a roadside verge in Maldegem, Belgium, and pressed using a screw press was suitable as a biofertilizer.Methods
The characterization of the heavy metal content of the GLF was conducted using an ICP-OES. From May to September 2019, a pot experiment was set up using a randomized block design to compare tomato plant growth, yield, and nutrition for GLF-treated plants to two commercial fertilizers and tap water as a control.Results
The heavy metal content of the GLF was below the maximum permissible concentrations (MPCs) for organic fertilizers as set out by the European Comission fertilizer regulation 1069/2009 and 1107/2009 (European Comission, 2019). However, despite having a fairly well-balanced nutrient content (0.1% N, 0.04% P2O5, and 0.2% K2O), GLF had a negative effect on the growth, root weight, and yield of the tomato plants, killing six out of ten plants. GLF also promoted mold growth in the soil of some plants. Since the GLF was uncontaminated, heavy metal toxicity did not cause the negative effect.Conclusions
Previous research showed that liquid fractions from some plants negatively affect the growth of others due to allelopathic chemicals; this, together with the stimulation of fungal growth, could have caused the negative effects observed. Future experiments will investigate the herbicidal property of GLF and possible treatments to potentially recover the nutrients contained within the GLF for application as a biofertilizer. 相似文献16.
Conservation of forest biodiversity and ecosystem properties in a pastoral landscape of the Ecuadorian Andes 总被引:1,自引:0,他引:1
High Andean cloud forests are home to a diversity of unique wildlife and are important providers of ecosystem services to people in the Andean regions. The extent of these cloud forests has been widely reduced through conversion to pasture for livestock, which threatens the forests’ ability to support biodiversity and provide ecosystem services. This paper explores whether impacts on woody plant biodiversity and four ecosystem properties (woody plant species richness, juvenile timber tree abundance, soil organic matter content and soil moisture) from converting forest to pasture can be mitigated if some woody forest vegetation is maintained within pastures. Woody vegetation in pastures was found to conserve those woody plant species that are more tolerant to exposure and grazing, but conservation of the high montane cloud forest community required areas of forest from which livestock were restricted. The sampled sites clustered according to woody plant species cover; these clusters represented a gradient from pasture with patches of shrubs to mature forest. Clusters differed in both woody plant species richness and number of juvenile timber trees whereas soil organic matter and soil moisture were observed to be similar among all clusters. This suggests that the different habitats may have some equivalent ecosystem properties. We conclude that the presence of woody vegetation in pastures may reduce some of the impacts of converting forest to pasture, but should not be considered a substitute for protecting large areas of forest, which are essential for maintaining woody plant species diversity in high Andean cloud forest. 相似文献
17.
Plant species richness and diversity in urban and peri-urban gardens of Niamey,Niger 总被引:1,自引:0,他引:1
Hannah Bernholt Katja Kehlenbeck Jens Gebauer Andreas Buerkert 《Agroforestry Systems》2009,77(3):159-179
Urban and peri-urban agriculture (UPA) significantly contributes to food and nutritional security of urban dwellers in many
African countries. Economic and demographic pressures often lead to transformation of subsistence-oriented traditional homegardens
into commercial production units. Such transformation is claimed to result in decreasing plant diversity, particularly of
local species. A study was therefore undertaken in 51 gardens of Niamey, Niger, to assess the factors determining plant diversity
and the suitability of UPA for in situ conservation of plant genetic resources. In each garden, the number and abundance of
all human-used plant species were determined, and species density, Shannon index and Shannon evenness were calculated. In
the 51 surveyed gardens, a total of 116 plant species were cultivated, most of them for the production of fruits or vegetables.
Annual vegetables dominated, particularly exotic species grown for sale. In the cold season, an average of 14 species were
cultivated per garden, the Shannon index was 0.96 and evenness was 0.39. Commercial gardens had a species richness similar
to that of subsistence gardens, but a lower evenness (P < 0.005), caused by the dominance of a few vegetable species. Gardens of immigrants had a lower Shannon index than those
of members of the local Djerma ethnic group. Stepwise multiple regression analysis showed significant influence of various
variables on plant species richness and diversity parameters: garden size (richness and Shannon index), ethnicity of the gardener
(richness and evenness), gender of the gardener and cash-oriented production (evenness), household size (richness) and garden
possession status (Shannon index). Cluster analysis revealed the existence of five garden types. The highest species richness
and diversity, particularly of perennial and local species, was found in large, peri-urban, commercial gardens managed by
relatively wealthy, elderly gardeners with large families and a regular non-agricultural income. 相似文献
18.
Nils Dittbrenner Hannah Schmitt Yvan Capowiez Rita Triebskorn 《Journal of Soils and Sediments》2011,11(6):1000-1010
Purpose
The use of only one or a few species—representing an entire taxon—in ecotoxicological standard tests poses risk of underestimating the impact of toxicants on the environment. In earthworm ecotoxicity tests, the species Eisenia fetida or Eisenia andrei are commonly used, and there is evidence that these species respond relatively insensitive towards environmental pollution. With the present study, we wanted to evaluate the risk of underestimating effects of the insecticide imidacloprid in soil organisms by comparing E. fetida with two other earthworm species (Aporrectodea caliginosa and Lumbricus terrestris) regarding their sensitivities towards soil contaminated with this widely used insecticide. 相似文献19.
Kathryn M. Santos Paul R. Fisher Thomas H. Yeager Eric H. Simonne Hannah S. Carter William R. Argo 《Journal of plant nutrition》2013,36(10):1424-1436
Fertilization strategies during stock plant and cutting production are linked in terms of cutting nutrient levels and quality. Objectives were to evaluate (1) the effect of stock plant nutrition on tissue nutrient concentration and growth during vegetative propagation and (2) response to fertilizer during propagation for cuttings with 4 different initial tissue nutrient concentrations. ‘Supertunia Royal Velvet’ petunia stock plants were grown under constant fertigation of 0, 50, 100 or 200 mg nitrogen (N).L?1 for 21 days. The 200 mg N.L?1 solution contained 150 nitrate (NO3-N), 50 ammonium (NH4-N), 24 phosphorus (P), 166 potassium (K), 40 calcium (Ca), 20 magnesium (Mg), 0.7 sulfur (S), 1.0 iron (Fe), 0.5 manganese (Mn), 0.5 zinc (Zn), 0.24 copper (Cu), 0.24 boron (B), and 0.1 molybdenum (Mo). Providing a complete fertilizer during propagation of petunia, beginning immediately after sticking of cuttings, reduces the risk of nutrient deficiency. Particularly in situations where fertilizer is not applied early during propagation, stock plants should be managed to ensure unrooted cuttings have adequate nutrient reserves. 相似文献
20.