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531.
This paper examines the discourses and practices of pedigree livestock breeding, focusing on beef cattle and sheep in the
UK, concentrating on an under-examined aspect of this—the deselection and rejection of some animals from future breeding populations.
In the context of exploring how animals are valued and represented in different ways in relation to particular agricultural
knowledge-practices, it focuses on deselecting particular animals from breeding populations, drawing attention to shifts in
such knowledge-practices related to the emergence of “genetic” techniques in livestock breeding which are arguably displacing
“traditional” visual and experiential knowledge’s of livestock animals. The paper situates this discussion in the analytical
framework provided by Foucault’s conception of “biopower,” exploring how interventions in livestock populations aimed at the
fostering of domestic animal life are necessarily also associated with the imperative that certain animals must die and not
contribute to the future reproduction of their breed. The “geneticization” of livestock breeding produces new articulations
of this process associated with different understandings of animal life and the possibilities of different modes of intervention
in livestock populations. Genetic techniques increasingly quantify and rationalize processes of selection and deselection,
and affect how animals are perceived and valued both as groups and as individuals. The paper concludes by emphasizing that
the valuation of livestock animals is contested, and that the entanglement of “traditional” and “genetic” modes of valuation
means that there are multiple layers of valuation and (de)selection involved in breeding knowledge-practices. 相似文献
532.
Helen A. Violi Alejandro F. Barrientos-Priego Sara F. Wright Esteban Escamilla-Prado Joseph B. Morton John A. Menge Carol J. Lovatt 《Forest Ecology and Management》2008
Mexican montane rainforests and adjacent disturbed areas were studied for disturbance-related spatio-temporal changes to the arbuscular mycorrhizal fungal (AMF) community and soil glomalin concentration. The AMF community functions to both improve plant growth and soil conditions and is thus an important component to the restoration of this forest type to disturbed areas. The study areas included mature rainforests that were converted to pine forests, milpas, pastures and shrub/herbaceous plant communities via burning and logging. Seasonal patterns in AMF spore species richness and sporulation significantly differed across disturbance types at two of the three sites surveyed. Contrasting patterns of sporulation among AMF families across different disturbance types helped to explain how species richness and composition were maintained despite dramatic changes to the host plant community. Meaning, in most cases, disturbance induced changes in when different AMF taxa sporulated but not what taxa sporulated. Only conversion from mature pine–oak–Liquidambar–Persea forests to pine-dominated stands severely reduced AMF spore richness and total sporulation. Surprisingly, in pine-dominant stands no concomitant negative impacts on soil glomalin (MAb32B11 immunoreactive soil protein) concentrations were detected. However, soils of mature forests containing no pines had the highest concentration of glomalin. Conversion to pasture and milpa (diverse cornfield) had a strong negative impact on the concentration of soil glomalin concentrations. In sharp contrast, the same disturbance types improved AMF sporulation and AMF spore richness. It appears that disturbance type, and not AMF community measures used herein, best predicts changes in soil glomalin concentration. 相似文献
533.
Im HW Suh BS Lee SU Kozukue N Ohnisi-Kameyama M Levin CE Friedman M 《Journal of agricultural and food chemistry》2008,56(9):3341-3349
Potato plants synthesize phenolic compounds as protection against bruising and injury from bacteria, fungi, viruses, and insects. Because antioxidative phenolic compounds are also reported to participate in enzymatic browning reactions and to exhibit health-promoting effects in humans, a need exists for accurate methods to measure their content in fresh and processed potatoes. To contribute to our knowledge about the levels of phenolic compounds in potatoes, we validated and used high-performance liquid chromatography and liquid chromatography/mass spectrometry to measure levels of chlorogenic acid, a chlorogenic isomer, and caffeic acid in flowers, leaves, stems, and tubers of the potato plant and in home-processed potatoes. The total phenolic acid content of flowers (626 mg/100 g fresh wt) was 21 and 59 times greater than that of leaves and stems, respectively. For all samples, chlorogenic acid and its isomer contributed 96-98% to the total. Total phenolic acid levels (in g/100 g fresh wt) of peels of five potato varieties grown in Korea ranged from 6.5 to 42.1 and of the flesh (pulp) from 0.5 to 16.5, with peel/pulp ratios ranging from 2.6 to 21.1. The total phenolic acid content for 25 American potatoes ranged from 1.0 to 172. The highest amounts were present in red and purple potatoes. Home processing of pulp with various forms of heat induced reductions in the phenolic content. The described methodology should facilitate future studies on the role of potato phenolic compounds in the plant and the diet. 相似文献
534.
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
535.
536.
537.
Lemke AA Wu JT Waudby C Pulley J Somkin CP Trinidad SB 《Genomics, society, and policy / ESRC Genomics Network》2010,6(3):35-52
Advances in genomic technologies and the promise of "personalised medicine" have spurred the interest of researchers, healthcare systems, and the general public. However, the success of population-based genetic studies depends on the willingness of large numbers of individuals and diverse communities to grant researchers access to detailed medical and genetic information. Certain features of this kind of research - such as the establishment of biobanks and prospective data collection from participants' electronic medical records - make the potential risks and benefits to participants difficult to specify in advance. Therefore, community input into biobank processes is essential. In this report, we describe community engagement efforts undertaken by six United States biobanks, various outcomes from these engagements, and lessons learned. Our aim is to provide useful insights and potential strategies for the various disciplines that work with communities involved in biobank-based genomic research. 相似文献
538.
Yasuhiro Ishiga Srinivasa Rao Uppalapati Takako Ishiga Carol L. Bender 《Journal of General Plant Pathology》2010,76(3):188-195
Coronatine (COR) functions as a virulence factor in the interaction of Pseudomonas syringae pv. tomato strain DC3000 with tomato and Arabidopsis. COR consists of two moieties, coronafacic acid (CFA) and coronamic acid (CMA).
Both COR and CFA function as structural and functional analogues of jasmonic acid (JA) and related signaling compounds such
as methyl jasmonate (MeJA) and JA-isoleucine (JA-Ile). The precise function of COR and whether MeJA functions as an analogue
of COR in disease development are not known. In this study, we analyzed whether the COR-defective mutant DB29, which is a
CFA− CMA− mutant of DC3000, could be complemented for virulence via the exogenous application of COR, CFA, or MeJA. When tomato seedlings
were inoculated with DB29 and supplemented with exogenous COR, the DB29 population multiplied in tomato seedlings and induced
disease phenotypes similar to wild-type DC3000. Although the addition of exogenous MeJA or CFA enhanced the multiplication
of DB29, wild-type disease phenotypes could not be restored with these compounds. Furthermore, inoculation of DB29 along with
exogenous COR, but not MeJA or CFA, suppressed the expression of defense-related genes and increased the accumulation of reactive
oxygen species, which are associated with severe chlorosis. Taken together, our results suggest that although COR targets
the jasmonate pathway by mimicking JA, the function of COR in disease development is distinctly different from MeJA or CFA. 相似文献
539.
540.
Extreme lymphocytosis with myelomonocytic morphology in a horse with diffuse large B‐cell lymphoma
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Kristina Meichner Jessica R. Durrant Carol B. Grindem Babetta A. Breuhaus Peter F. Moore Jennifer A. Neel Keith E. Linder Luke B. Borst Jonathan E. Fogle Jaime L. Tarigo 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2017,46(1):64-71
An 11‐year‐old, 443‐kg Haflinger mare was presented to the North Carolina State University Veterinary Teaching Hospital with a 2‐week history of lethargy and a 3‐day duration of anorexia, pyrexia, tachycardia, and ventral edema. Severe pitting edema, peripheral lymphadenopathy, and a caudal abdominal mass were noted on physical examination. An extreme leukocytosis (154.3 × 103/μL) and microscopic hematologic findings suggestive of myelomonocytic leukemia were observed. Serum protein electrophoresis revealed a monoclonal gammopathy and urine protein electrophoresis revealed a monoclonal light chain proteinuria. Necropsy and histopathology confirmed widespread neoplastic infiltration in many organs with a heterogenous population of cells; there was no apparent evidence of bone marrow involvement. Immunohistochemistry confirmed presence of a majority of B cells with a limited antigen expression, admixed with a lower number of T cells. Molecular clonality analysis of IgH2, IgH3, and kappa‐deleting element (KDE, B cell) on whole blood and KDE on infiltrated tissues revealed clonal rearrangements, and the KDE intron clones that amplified in blood and in infiltrated tissue were identical. In contrast, the clonality analysis of T‐cell receptor γ revealed no clonality on blood cells and infiltrated tissues. In conjunction with the histopathologic changes, the lesion was interpreted to be composed of neoplastic B cells with a reactive T‐cell population. Polymerase chain reaction testing for equine herpes virus 5 was negative. The final diagnosis was diffuse large B‐cell lymphoma with a marked hematogenous component. 相似文献