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71.
David A. Rubinos Rafael Villasuso Soledad Muniategui María Teresa Barral Francisco Díaz-Fierros 《Water, air, and soil pollution》2007,178(1-4):385-399
The purpose of the present study is to simulate concentrations of ozone and its precursors (NO and NO2) in an area under the influence of the Candiota coal-fired power station by applying numerical models. The photochemical simulations were conducted during two distinct periods: in summer (from 24 to 26 January 2003) and in winter (from 10 to 12 August, 2004). With the RAMS atmospheric model (Regional Atmospheric Modelling System) we obtained meteorological fields to initialize the CIT photochemical model. The emission data were based on the AP-42 and only compounds emitted during coal burning were considered. The simulated results revealed high ozone levels in warmer periods, being related to high temperatures and water vapor concentrations. The simulated concentrations are located far from the emitting source, favoring reaction and mixing time between precursors to form ozone. Simulated winds of small intensity favored ozone transport, mixing and accumulation in areas far from the emitting source. 相似文献
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Lethal trait A 46 in cattle. Immunological investigations 总被引:1,自引:0,他引:1
74.
K N Gelatt D A Samuelson J E Bauer N D Das E D Wolf K P Barrie T L Andresen 《American journal of veterinary research》1983,44(6):1130-1132
Congenital cataracts and microphthalmia in the Miniature Schnauzer were inherited as an autosomal recessive trait. Eighteen matings of affected X affected Miniature Schnauzers resulted in 87 offspring with congenital cataracts and microphthalmia (49 males/38 females). Two matings of congenital cataractous and microphthalmic Miniature Schnauzers (2 females) X a normal Miniature Schnauzer (1 male) yielded 11 clinically normal Miniature Schnauzers (7 males/4 females). Eighteen matings of congenital cataractous and microphthalmic Miniature Schnauzers (6 males) X carrier Miniature Schnauzers (9 females) produced 81 offspring; 39 exhibited congenital cataracts and microphthalmia (20 males/19 females) and 42 had clinically normal eyes (17 males/25 females). 相似文献
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76.
Richard D Garman Michael F Lyons Kelton P Hepper George W Teresa 《Comparative immunology, microbiology and infectious diseases》1979,2(4):531-543
A Boivin lipopolysaccharide-protein complex (LPS-P), Westphal LPS (W-LPS), Boivin LPS (B-LPS), and a lipid A-associated protein (LAP) were extracted from Fusobacterium necrophorum bov 5 strain and chemically analyzed for protein, total nitrogen, hydrolyzed hexosamine, and nucleic acid content. Dose and time effects on the in vitro cytotoxicity of these preparations for mouse peritoneal macrophages were determined. Macrophage monolayers were exposed to 2.0 ml of 10, 100, 250, 500, or 1000 μg/ml solutions of the individual preparations for 1, 2, 4, or 6 hr at 37°C, and relative toxicities were determined; B-LPS> LPS-P> LAP, W-LPS. The effects of heat, NaOH, and trypsin and pronase on the native antigens were determined. Heat treatment had no effect on the cytotoxicity of B-LPS, but increased the toxicity of LPS-P and LAP for macrophages. Alkaline treatment decreased the cytotoxicity of B-LPS and increased the toxicity of LPS-P and LAP for macrophages. Enzyme treatment had no effect on LPS-P toxicity. The relationship of lipid A and protein content to toxicity for macrophages is discussed. Lipid A appears to be important in the cytotoxicity of B-LPS, and the protein components of LPS-P and LAP may contribute to their toxic activity. The ability of these bacterial cellular antigens to destroy phagocytic cells may facilitate the establishment of necrotic abscesses in susceptible hosts. 相似文献
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79.
An 8-year-old, spayed female Domestic Short-haired cat was referred for further evaluation of chronic lymphocytic-plasmacytic stomatitis and bilateral ocular disease. The cat had been treated with systemic glucocorticoids for several months. Initial ophthalmic examination revealed bilateral deep stromal corneal ulcers, exudative panuveitis and secondary glaucoma. Mature mild neutrophilia and monocytosis were detected on complete blood cell count. Abnormalities in the serum profile were hyperglycemia, mild azotemia, hyperglobulinemia and moderate polyclonal gammapathy. Urinalysis revealed glucosuria without ketonuria. Diabetes mellitus was diagnosed and treatment with long-acting insulin was started. An enzyme-linked immunosorbent assay was highly positive for leishmaniasis, and treatment with allopurinol was started. Although specific topical treatment was applied, melting ulcers progressed to corneal perforation and both eyes were enucleated. Ocular histology showed large numbers of intracellular organisms compatible with amastigotes of the genus Leishmania located in the uveal tract, cornea, sclera and retina. Results of inmunohistochemistry staining on ocular samples were positive for Leishmania. Bone marrow cytology demonstrated numerous macrophages with intracytoplasmatic Leishmania. Polymerase chain reaction results on bone marrow for Leishmania were positive. Three weeks later, hypoglycemic episodes permitted withdrawal of the insulin therapy. To the authors' knowledge this is the first case of ocular and visceral leishmaniasis diagnosed in vivo and under systemic treatment in a cat. 相似文献
80.
Three air contaminants that may have serious health consequences to humans and poultry are ammonia, dust, and aerosolized bacteria. This study measured ammonia concentrations, dust concentrations, and the presence or absence of aerosolized Salmonella spp. and Escherichia coli inside and outside five commercial layer facilities. The average outside ammonia concentration measurements decreased as the distance from the facility increased from 10 to 40 ft. The measurements at 10 ft from the facilities were consistently higher than the average concentrations inside the facilities. The ammonia measurement trends inside of the facilities were affected by the temperature-dependent ventilation systems. Average dust concentrations inside the five facilities were consistently below 2 mg/m3. Three facilities also experienced average outside dust concentrations at all measured distances below 2 mg/m3. Two facilities had relatively high average dust measurements at 10 ft from ventilation fans (32.12 mg/m3 and 75.18 mg/m3). Escherichia coli and Salmonella were isolated from the air inside all five facilities and outside the facilities up to 40 ft from the ventilation fans. In condusion, dust concentrations may pose the largest risk to human and animal health at 10 ft away from the poultry facilities; risks associated with ammonia inhalation are greatest inside facilities during the coolest months of the year; and aerosolized bacteria are found inside and outside poultry facilities, but further work is needed to quantify the bacteria to further assess the health risk related to this issue. 相似文献