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171.
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
172.
173.
María Delclaux Covadonga Talavera Manuel López Jose Miguel Sánchez María Isabel García 《Journal of zoo and wildlife medicine》2002,33(3):283-285
A 17-mo-old captive-born female red panda (Ailurus fulgens fulgens) presented with a sudden onset of lameness in its left hind leg was diagnosed radiographically as having possible severe, bilateral Legg-Calve-Perthes disease with fracture of the great trochanter of the left femur. Surgical repair of the fracture was performed using pins and a tension band wire through a lateral approach to the hip. This is the first case reported at Madrid Zoo-Aquarium, where 63 individuals have been bred over 15 yr. 相似文献
174.
M P Jiménez de Bagüés C M Marín J M Blasco I Moriyón C Gamazo 《Veterinary microbiology》1992,30(2-3):233-241
An indirect enzyme-linked immunosorbent assay (ELISA) with unpurified Brucella melitensis smooth lipopolysaccharide (S-LPS) as antigen was evaluated for the serological diagnosis of B. melitensis infection in sheep in comparison with the Rose Bengal (RB), complement fixation (CF), radial immunodiffusion (RID), microplate agglutination (MA) and rivanol agglutination (RIV) tests. Tests RB and CF detected as positive each of the 77 sera from B. melitensis-infected animals tested, the RID (74), MA (76) and the RIV (72) were less sensitive. However, all tests compared were negative when 77 sera from Brucella-free rams were tested. While subcutaneous Rev 1 vaccination induced high response levels in any of the tests, low level responses were obtained upon conjunctival vaccination, particularly in ELISA and RID tests. 相似文献
175.
Effect of chlorimuron-ethyl on Bradyrhizobium japonicum and its symbiosis with soybean 总被引:1,自引:0,他引:1
Possible side-effects of the acetolactate synthase (ALS)-inhibiting herbicide chlorimuron-ethyl on Bradyrhizobium japonicum (Kirchner & Jordan) in pure culture and on inoculated soybean plants growing under controlled conditions were investigated. Growth of B japonicum strain E109 was not affected by this herbicide even when exposed to concentrations 150 times higher than recommended field doses. However, nodulation of soybean plants treated 5 days after emergence with chlorimuron-ethyl at standard application rates was impaired: a 38% decrease in the number of nodules per plant was observed four weeks after treatment. Despite nodule number decrease, no changes in shoot nitrogen content could be detected. Total fresh biomass was diminished by 25% in herbicide-treated plants. Leghemoglobin content in nodules did not vary; nevertheless total nodule protein was diminished by 40% in the herbicide-treated group. ALS activity in different soybean tissues and their relative sensitivity to chlorimuron-ethyl were also investigated. Roots and bacteroids had the greatest specific ALS activities. On a fresh weight basis, the bacteroid fraction displayed the highest ALS activity and was also the most tolerant to in vitro chlorimuron addition: 72% of its activity was retained after including 10 microM chlorimuron-ethyl in the reaction mixture. These results indicate that standard application rates of chlorimuron-ethyl will have limited incidence on B japonicum survival, and effects on nodulation may have little long-term consequences on soybean nitrogen fixation potential. The differences found among soybean tissues not only in intrinsic ALS activity but also in their relative sensitivity to this herbicide suggests that, in leguminous plants living in symbiosis with rhizobia, nodules may contribute to an enhanced tolerance to ALS inhibitors. 相似文献
176.
177.
Fayos M Couto CG Iazbik MC Wellman ML 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):397-400
BACKGROUND: Retired racing Greyhounds are becoming common as pets. Because of their unique physiology, results of routine laboratory tests are frequently outside the reference interval for dogs. Compared with other breeds, Greyhounds have low serum protein concentrations, but the concentrations of different serum protein fractions have not been reported. OBJECTIVES: Our objectives were to evaluate the results of serum protein electrophoresis (SPE) in healthy, retired racing Greyhounds and compare them with a control group of age- and gender-matched non-Greyhound dogs. METHODS: Agarose gel electrophoresis was done using a standard method; the gels were stained with amido black and scanned with a Cliniscan 2 densitometer (Helena Laboratories, Beaumont, TX, USA). Protein fractions were identified by visual inspection of the electrophoretogram. A Student's t-test assuming equal variances was used to compare the concentration of the different fractions between groups. RESULTS: The concentrations of total protein, total globulins, and alpha-1-, alpha-2-, beta-1-, and beta-2-globulins were significantly lower and the albumin to globulin (A:G) ratio was significantly higher in Greyhounds than in non-Greyhound dogs (P < .05). There was no significant difference in albumin or gamma-globulin concentrations. CONCLUSIONS: Low serum protein concentrations in Greyhounds are the result of low concentrations of a- and b-globulins. These results should be kept in mind when evaluating both healthy and sick Greyhounds. Additional studies are needed to identify the individual proteins associated with low alpha- and beta-globulin concentrations in Greyhounds. 相似文献
178.
Santos M López-Sanromán J García-Iturralde P Fuente M Tendillo FJ 《Veterinary anaesthesia and analgesia》2005,32(6):355-359
OBJECTIVE: To determine the cardiopulmonary effects of desflurane (DES) in horses. ANIMALS: Six healthy adult horses, three males and three females, aged 9 +/- 4 (mean +/- SD) years and weighing 370 +/- 36 kg. MATERIALS AND METHODS: Anaesthesia was induced with an O2 (10 L minute(-1)) and DES mixture (vaporizer setting 18%). After oro-tracheal intubation, horses were positioned in right lateral recumbency. Anaesthesia was maintained with DES in O2 (20 mL kg(-1) minute(-1)) delivered through a large animal circle breathing system. The minimum alveolar concentration of DES (MAC(DES)) that prevented purposeful movement in response to 60 seconds of electrical stimulation of the oral mucous membranes was determined for each horse. The delivered concentration of DES was then increased to achieve end-tidal concentrations corresponding to 1.5 x MAC(DES), 1.75 x MAC(DES), and 2.0 x MAC(DES). Heart rate (HR), mean arterial blood pressure (MAP), respiratory rate (fr), tidal volume (VT), minute volume (VM) and core temperature were determined, and blood samples for arterial blood gas analysis taken at each DES concentration. All data were analysed by two-way anova for repeated measures and Fisher's test for multiple comparisons. A probability level of p < 0.05 was applied. RESULTS: Desflurane concentrations of 2.0 x MAC(DES) increased HR whereas lower concentrations did not. Mean arterial pressure was not affected by 1.0 x MAC(DES) 1.5 x MAC(DES) or 1.75 x MAC(DES), whereas it decreased at 2.0 x MAC(DES). All concentrations of DES examined significantly depressed fr, VT and VM. CONCLUSIONS AND CLINICAL RELEVANCE: Desflurane concentrations between 1.0 and 1.75 x MAC(DES) reduces fr and VM but does not affect HR or MAP in horses. 相似文献
179.
León LG Ostronoff LK Fermín ML Fragío C Kremmer E Kolb HJ Tejero C 《Veterinary immunology and immunopathology》2005,107(1-2):41-50
The major goal of this work was to describe the in vitro generation of mature functional neutrophils derived from a canine enriched haematopoietic progenitor cell population. We have utilised lineage depletion by immunomagnetic selection to isolate a canine haematopoietic progenitor cell population. The physical, immunological, metabolical and morphological methodologies employed in this study have permitted us to isolate and define a cell population enriched in Rh-123low and CD34+ cells. Irradiated pre-established long-term bone marrow cultures (LTBMC) were utilised to determine the self-renewal ability of lineage negative (Lin-) cells, as well as their capacity to differentiate into mature functional neutrophils. The authors demonstrate for the first time that canine neutrophils derived from Lin- cells are able to produce oxyradicals, express a specific neutrophil surface antigen, and contain gelatinase granules. These characteristics enable them to migrate through basement membranes to act as a first line defence mechanism. The fact that these cells are able to differentiate into functional mature cells, and give rise to long-term culture-initiating cells (LTC-IC) after 35 days of culture, allows the authors to assure that the isolated canine enriched haematopoietic cell population exhibit functional characteristics, associated with primitive haematopoietic cells. 相似文献
180.
Cárceles CM Font A Escudero E Espuny A Marín P Fernández-Varón E 《Journal of veterinary pharmacology and therapeutics》2005,28(5):475-479
The pharmacokinetics (PK) of azithromycin after i.v. and i.m. injection at a single dosage of 20 mg/kg bodyweight was studied in sheep. Blood samples were collected from the jugular vein until 120 h after dosing for both routes. Plasma concentrations of azithromycin were determined by bioassay. The plasma concentration-time data of azithromycin best fitted a three-compartment model after i.v. administration and a two-compartment model with first-order absorption after i.m. administration. The elimination half-life (t(1/2lambdaz)) was 47.70 +/- 7.49 h after i.v. administration and 61.29 +/- 13.86 h after i.m. administration. Clearance value after i.v. dosing was 0.52 +/- 0.08 L/kg.h. After i.m. administration a peak azithromycin concentration (C(max)) of 1.26 +/- 0.19 mg/L was achieved at 1.24 +/- 0.31 h (t(max)). Area under the curve (AUC) were 38.85 +/- 5.83 mg.h/L and 36.03 +/- 1.52 mg.h/L after i.v. and i.m. administration respectively. Bioavailability obtained after i.m. administration was 94.08 +/- 11.56%. The high tolerability of this i.m. preparation and the favourable PK behaviour such as the long half-life and high bioavailability make azithromycin likely to be effective in sheep. 相似文献