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51.
Donal O'Toole Elizabeth S Williams Leslie W Woods Kenneth Mills Amy Boerger-Fields Donald L Montgomery Paula Jaeger William H Edwards Dwayne Christensen William Marlatt 《Journal of veterinary diagnostic investigation》2008,20(4):508-513
Abortion and death caused by Francisella tularensis were well recognized in range flocks of domestic sheep in Idaho, Montana, and Wyoming in the first 6 decades of the 20th century. The current report describes 4 episodes of tularemia in 3 range flocks in Wyoming and South Dakota in 1997 and 2007 (1 flock was affected twice). Flock owners reported that ticks were unusually numerous and commonly present on sheep during outbreaks. Tularemia presented as late-term abortions (3 episodes) or listlessness and death in lambs and, to a lesser extent, ewes (1 episode). Lesions were multifocal pinpoint necrotic foci in tissues, particularly spleen, liver, and lung. An immunohistochemical procedure demonstrated F. tularensis, particularly in necrotic foci. The diagnosis was corroborated by bacterial isolation and, in individual cases, by serology, fluorescent antibody assay, and/or polymerase chain reaction detection of F. tularensis. Diagnosticians in endemic areas should include tularemia as a differential diagnosis when investigating late-term abortions or outbreaks of fatal illness in young lambs, particularly in years of high tick activity and when characteristic necrotic foci occur in spleen, liver, and lung. 相似文献
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53.
Development of a class-selective enzyme-linked immunosorbent assay for mercapturic acids in human urine 总被引:2,自引:0,他引:2
Lohse C Jaeger LL Staimer N Sanborn JR Jones AD Langó J Gee SJ Hammock BD 《Journal of agricultural and food chemistry》2000,48(12):5913-5923
Epidemiological and toxicological studies often require the analysis of large numbers of samples for biological markers of exposure. The goal of this work was to develop a class-selective ELISA to detect groups of structurally closely related mercapturic acids with small nonpolar S-substituents. An assay was developed with strong recognition for mercapturates including S-benzylmercapturic acid (IC50 = 0.018 micromol/L), S-n-hexylmercapturic acid (IC50 = 0.021 micromol/L), S-phenylmercapturic acid (IC50 = 0.024 micromol/L), and S-cyclohexylmethylmercapturic acid (IC50 = 0.042 micromol/L). The same assay also showed weaker recognition for S-(1-hydroxynaphthal-2-yl)mercapturic acid and S-allylmercapturic acid (IC50 = 1.1 and 1.7 micromol/L, respectively). Subtle modifications to the hapten linker structure of the coating antigen proved to have a strong impact on the selectivity and the specificity of the assay. A slightly modified assay showed high recognition for S-benzylmercapturic acid (IC50 = 0.018 micromol/L) and weaker recognition for seven other mercapturic acids (IC50 = 0.021-10 micromol/L). Strong positive assay responses were detected in 12 urine samples obtained from persons with no known occupational exposure to exogenous electrophilic xenobiotics. Solid phase extraction and cross-reactivity indicated that the presumptive immunoreactive materials were similar in size and polarity to S-benzylmercapturic acid. The assay was more selective to mercapturic acids than the spectrophotometric thioether assay. 相似文献
54.
Dietrich Werner Regine Berggold Dieter Jaeger Arno Krotzky Hans Papen Sigrid Schenk Heidemarie Thierfelder 《植物养料与土壤学杂志》1989,152(2):231-236
A genotype effect on associative (rhizosphere) N2-fixation was observed with two cultivars of Sorghum bicolor (nutans) with a maximum rate of 8 μmol C2H4 · h?1 · plant?1 in one genotype compared to 0.9 μmol in the other. Characteristics of the high fixing genotype were a reduced transpiration rate, a lower number of stomata and increased root exudate production per gram root dry weight with higher concentration of dicarboxylic acids. The bacterial rhizosphere composition revealed a three times higher number of N2-fixing bacteria, a tenfold reduction of actinomycetes and a threefold reduction of Arthrobacter associated with the high fixing cultivar compared to the low fixing genotype. From these and other plant rhizospheres two new nitrogen fixing bacteria, Pseudomonas stutzeri and Erwinia herbicola, were characterized. With the N2-fixing bacteria Azospirillum brasilense and Klebsiella pneumoniae an enhancement of specific nitrogenase activity by aromatic compounds, for example phenolics, the herbicide alachlor and the insecticide carbofuran was demonstrated. An oscillating nitrogenase activity in Azospirillum brasilense under microaerobic conditions was found, resulting from an encystation and deencystation under those conditions. Experiments with wheat roots demonstrated that reduced oxygen tensions, essential for a maximum rhizosphere N2-fixation, reduced root growth significantly and altered the N-metabolism of the roots. 相似文献
55.
Major health conditions in sheep contribute to substantial economic losses throughout the sheepmeat supply chain in Australia. A systematic review was undertaken to explore the measurable impact of six conditions: arthritis, sheep measles, pleurisy, pneumonia, grass seeds and rib fractures, on the production of lamb and mutton across the meat value chain. Peer‐reviewed scientific literature from three databases and non‐peer‐reviewed articles and reports from Australian government and non‐government websites were searched between 11 and 17 November 2019. Original articles, including studies conducted in Australia and New Zealand, that had measurable impacts on conditions of interest were included. The search yielded 16 articles and reports and were classified as producer impact and/or processor impact studies. Mortalities were quantified for pneumonia and arthritis, with pneumonia having the highest impact for producers. Grass seed infestation resulted in the highest impact on carcase and liveweight losses compared to arthritis and pneumonia. Arthritis had the highest trim weight losses for both lamb and mutton and the highest rate of carcase condemnation. Grass seed was the only condition where other impacts on the processor (chain speed and staff relocation to the boning room) were quantified. Although quantifiable production and processing losses were available for some conditions, this review has highlighted that limited quantifiable data based on scientifically sound research were not available for other conditions. The evidence for some conditions found in this review can be used to target future research activities and to further assist producers in making informed management decisions on prevention and control. 相似文献
56.
A 7-years-old Clydesdale mare was presented with severe abdominal distension and acute colic. Dilated large intestine was palpated per rectum and a ventral midline exploratory laparotomy was performed. A 180 degrees volvulus of the pelvic flexure was present, associated with an inelastic band of tissue connecting the mesocolon to the umbilicus. The band was ligated and transected, and the volvulus reduced. Postoperative complications included hyponatraemia, metabolic acidosis and laminitis. The possible aetiology of the mesocolic-umbilical band is discussed. 相似文献
57.
Primates living today are believed to share a common ancestor that originated in either Africa or Asia. Fossil examples of such anthropoid ancestors have been found in both continents, so pushing back the origins to a single location has been controversial. In their Perspective, Jaeger and Marivaux discuss results reported in the same issue by Seiffert et al. that may put part of the controversy to rest. Seiffert et al. describe the earliest and most complete African anthropoid fossils from the Fayum desert region of Egypt. Cranial and dental fossils of two different small species were found, and their character, especially the features of the fossil teeth, suggests an ancient evolutionary history in Africa. At the same time, the phylogenetic analysis of Seiffert et al. is consistent with the view that African anthropoids immigrated from Asia at a very early date, probably before the late Paleocene (60 million years ago), possibly followed by later waves of immigration. 相似文献
58.
Britto Pedro Caldas Jaeger Dirk Hoffmann Stephan Robert Renato Cesar Gonalves Vibrans Alexander Christian Fantini Alfredo Celso 《European Journal of Forest Research》2022,141(4):665-681
European Journal of Forest Research - Subject to overexploitation in the past centuries, the Atlantic Forest is subject to very rigorous protection rules. However, the law is a controversial issue... 相似文献
59.
Skeletal ontogeny in extant archosaurians (crocodilians and birds) indicates that the morphology of the perinatal pelvic girdle is an indicator of overall developmental maturity [that is, altriciality (nestbound) versus precociality (mobile and relatively independent)]. Comparison of the skeletal anatomy of perinatal extant archosaurians and perinatal dinosaurs suggests that known dinosaur hatchlings were precocial. These data are consistent with the overall similarity in nesting behavior of dinosaurs and modern crocodilians. 相似文献
60.