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排序方式: 共有887条查询结果,搜索用时 15 毫秒
801.
Delgado C Lee-Fowler TM DeClue AE Reinero CR 《Journal of Feline Medicine and Surgery》2010,12(12):991-994
Immunoglobulin E (IgE) plays an important role in defense against parasitic infections as well as allergy. Knowledge of serum total IgE concentrations may have value in diagnosis and prognostication of various disorders; however, to date, no studies have reported feline serum total IgE concentrations. We hypothesize that serum total IgE concentrations will be greater in spontaneously parasitized and asthmatic cats compared to healthy pet cats. Healthy (n=10), parasitized (10) and asthmatic cats (eight) had measurement of serum total IgE by ELISA. Data were analyzed using a t-test with P<0.05 considered significant. Serum total IgE was higher in parasitized (mean±SEM, 328.4±123.8μg/ml; P<0.028) and asthmatic cats (85.5±19.5μg/ml; P<0.047) compared to healthy cats (45.9±19.6μg/ml). However, serum total IgE had poor discriminatory capability between diseased and healthy cats. In conclusion, this assay can detect small quantities of feline serum total IgE, which may be beneficial in future studies of parasitism or allergic disease. 相似文献
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Kiah Smith Geoffrey Lawrence Amy MacMahon Jane Muller Michelle Brady 《Agriculture and Human Values》2016,33(1):45-60
This paper provides new insights into the food security performance of long and short food chains, through an analysis of the resilience of such chains during the severe weather events that occurred in the Australian State of Queensland in early 2011. Widespread flooding cut roads and highways, isolated towns, and resulted in the deaths of people and animals. Farmlands were inundated and there were food shortages in many towns. We found clear evidence that the supermarket-based (long) food chain delivery system experienced significant difficulties in supplying food to flood-affected towns. In contrast, more localized (short) food supply chains—which relied upon supply from growers in peri-urban areas and community-based food initiatives—remained largely intact, and provided food at a time when the supermarkets were limited in their ability to respond to consumer demand. However, on closer examination of food distribution during flooding in the regional city of Rockhampton and in the State capital, Brisbane, the demarcation of success between “long” and “short” food chains became blurred. Both types of food supply chains shared some key resilience characteristics in responding to crisis but diverged in other important ways. We argue that conceptualizing food chains in terms of key elements of resilience—scale, diversity, flexibility and cohesion—may be more fruitful than the short-long dichotomy alone. This approach is particularly useful when prioritizing food security as the basis for evaluating food system sustainability in a context of predicted increases in extreme weather events and future climate change. 相似文献
804.
Troy A. Hottle Marisol Luna Agüero Melissa M. Bilec Amy E. Landis 《Compost science & utilization》2016,24(3):159-173
This research evaluates the addition of alkaline amendments to enhance the degradation of polylactic acid polymers (PLA) in compost conditions. The use of compostable biopolymers is increasing in part because they are advertised as compostable. However, PLA degrades slowly compared to the organic wastes in compost and even when processed in commercial composting facilities may not fully break down. This results in the accumulation of biopolymers in compost facilities and increased difficulty in identifying and removing contamination from traditional plastics. Alkaline amendments were used to accelerate the degradation of two PLA products in compost conditions. Six flasks containing food scraps, compost inoculant, and an alkaline amendment were set up as bioreactors with half containing clear PLA and the others including opaque PLA. The six bioreactors were incubated for 22 days. The mass loss and final visual inspection, including microscopy, showed increased degradation within the bioreactors containing the alkaline treatments. These results show that the addition of alkaline amendment to composting systems may enable more effective processing of biopolymers, expanding the range and quantity of wastes that can be processes. The enhanced degradation of biopolymers in compost may enable greater diversion rates for institutions and cities by enabling the acceptance of biopolymers and any mixed organics stream which includes biopolymers wastes. 相似文献
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Kathryn Corio Amy Wolf Michael Draney Gary Fewless 《Forest Ecology and Management》2009,258(7):1059-1066
The invasion of exotic earthworms in previously earthworm-free northern deciduous forests has been linked to the disappearance of forest floor litter, declines in plant species richness, and the development of monotypic stands of Carex pensylvanica. However, the impact of exotic earthworms on the regeneration of trees and understory plants is largely unknown. We examined the relationships between earthworm density, plant species richness, leaf litter accumulation, number of tree (Acer) seedlings, and cover of C. pensylvanica at 14 sites in mesic hardwood forests of the Chequamegon-Nicolet National Forest in northern Wisconsin. Earthworm biomass, especially of the genera Lumbricus, Aporrectodea, and Octolasion was negatively associated with leaf litter mass and number of Acer seedlings. Nine plant species, including two spring ephemerals (Dicentra cucullaria and Osmorhiza claytonii), a sedge (Carex deweyana), and an invasive mint (Galeopsis tetrahit) were negatively correlated with exotic earthworm densities. Dryopteris intermedia and Allium tricoccum, on the other hand, were associated with high earthworm densities. The activities of exotic earthworms appear to have significant impacts on Acer regeneration and the persistence of many herbaceous plants. Our findings suggest that the effects of exotic earthworms on litter mass are strongly related to the observed effects on species composition. Sensitive species can be used as indicators of high and low earthworm densities and might be useful for identifying forests of high conservation value where future invasions of exotic earthworms should be prevented. 相似文献
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Boutros M Kiger AA Armknecht S Kerr K Hild M Koch B Haas SA Paro R Perrimon N;Heidelberg Fly Array Consortium 《Science (New York, N.Y.)》2004,303(5659):832-835
A crucial aim upon completion of whole genome sequences is the functional analysis of all predicted genes. We have applied a high-throughput RNA-interference (RNAi) screen of 19,470 double-stranded (ds) RNAs in cultured cells to characterize the function of nearly all (91%) predicted Drosophila genes in cell growth and viability. We found 438 dsRNAs that identified essential genes, among which 80% lacked mutant alleles. A quantitative assay of cell number was applied to identify genes of known and uncharacterized functions. In particular, we demonstrate a role for the homolog of a mammalian acute myeloid leukemia gene (AML1) in cell survival. Such a systematic screen for cell phenotypes, such as cell viability, can thus be effective in characterizing functionally related genes on a genome-wide scale. 相似文献
810.
Amy M. Grooters DVM David S. Biller DVM Heidi Ward DVM Takayoshi Miyabayashi BVS MS C. Guillermo Couto DVM 《Veterinary radiology & ultrasound》1994,35(6):468-472
Abdominal ultrasonography was performed in seven cats with intestinal lymphoma and four cats with gastric lymphoma. Ultrasonographic abnormalities included the presence of a hypoechoic mass associated with the gastrointestinal tract, focal or diffuse thickening of the gastric wall, symmetric thickening of the bowel wall, loss of the normal layered appearance of the gastrointestinal wall, and abdominal lymphadenopathy. The thickness of the stomach wall ranged from 8 to 22 mm in cats with gastric lymphoma, and the thickness of the bowel wall ranged from 5 to 20 mm in cats with intestinal lymphoma. Fine needle aspiration of a gastrointestinal lesion was performed without complication in six cats, and was diagnostic for lymphoma in five out of six. Results of this study indicate that ultrasonography is an effective noninvasive means of identifying lesions consistent with alimentary lymphoma in cats. 相似文献