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631.
In order to evaluate low temperature tolerance of five variable somaclones as well as the cv. Peter Pears of gladiolus (Gladiolus grandiflorus Hort.) from which they were originated, catalase (CAT) activity and hydrogen peroxide (H2O2) level were measured. Before carrying out the analyses, vitroplants of these clones were exposed, during 21 days, to 8 °C temperature. In response to the stress generated by this low temperature, catalase (CAT) activity revealed on native gel and quantified by spectrophotometry, showed variable levels, being all of them higher compared to cultivar control. For these clones, strong CAT activities were always accompanied by low H2O2 levels. Thus, at low temperatures the antioxidants system of adapted clones is more active compared to control. 相似文献
632.
Cárceles Rodríguez B. Zuazo V. H. Durán Rodríguez M. Soriano Ruiz B. Gálvez García-Tejero I. F. 《Eurasian Soil Science》2021,54(5):792-806
Eurasian Soil Science - The rainfed mountain plantations in semiarid areas of the Mediterranean region with conventional practices register soil erosion values much higher than soil formation... 相似文献
633.
Marta Amat Susana Le Brech Tomàs Camps Carlos Torrente Valentina M. Mariotti José L. Ruiz Xavier Manteca 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(1):19-25
Aggression is one of the most common behavioral problems in dogs and may have important negative effects on public health, human–animal bond, and animal welfare. There is ample evidence showing a negative correlation between serum serotonin concentration and aggressive behavior in a variety of species, including the domestic dogs. This negative correlation is particularly pronounced in dogs that show impulsive aggression. Data obtained in some previous studies suggest that the English cocker spaniel (ECS) is more likely to show impulsive aggression than other breeds. Therefore, the aim of this study was to analyze possible differences in serum serotonin levels between aggressive ECS and aggressive dogs of other breeds. Nineteen ECSs presented for aggression at the Animal Behavior Service (School of Veterinary Science, Barcelona, Spain) were evaluated and compared with 20 aggressive dogs of other breeds attended at the same center. Serum serotonin levels were measured using an enzyme-linked immunosorbent assay method. Statistical analysis was done using the SPSS 15.0 for Windows. Aggressive ECSs had significantly (P < 0.001) lower levels of serum serotonin than aggressive dogs of other breeds (318.6 ± 67.1 and 852.77 ± 100.58 ng/mL, respectively). Variances were not significantly different between ECSs and other breeds (standard deviation = 449.84 ng/mL vs. 292.47 ng/mL, P > 0.05). This finding may explain why ECSs are more likely to show impulsive aggression than other breeds, and suggests that the ECS could be a good model to study the neurophysiologic mechanisms underlying impulsive aggression. 相似文献
634.
Martínez-Carrasco C Berriatua E Garijo M Martínez J Alonso FD de Ybáñez RR 《Zoonoses and public health》2007,54(5):195-203
The prevalence and risk factors of non-systemic canine ecto- and endoparasitism and anthelminthic use in Murcia located at the centre of the Spanish Mediterranean coastal arch, was investigated by coprology and necropsy in up to 275 pet, city shelter and stray dogs in 2001-2004. Faecal parasite stages were detected in 25% of dogs. Species frequency was 6-10% for Toxocara canis, Ancylostomatidae spp., Toxascaris leonina and Isospora canis, and 0.4-1% for Trichuris vulpis, Giardia lamblia, and Dipylidium caninum. Logistic regression indicated that the risk of intestinal parasitism was highest for dogs 相似文献
635.
Ruiz LM Orduz S López ED Guzmán F Patarroyo ME Armengol G 《Veterinary parasitology》2007,144(1-2):138-145
Plasmid pBMC2 encoding antigen Bm86 from a Colombian strain of cattle tick Boophilus microplus, was used for DNA-mediated immunization of BALB/c mice, employing doses of 10 and 50microg, delivered by intradermic and intramuscular routes. Anti-Bm86 antibody levels were significantly higher compared to control mice treated with PBS. In the evaluation of immunoglobulin isotypes, significant levels of IgG2a and IgG2b were observed in mice immunized with 50microg of pBMC2. Measurement of interleukine (IL) levels (IL-4, IL-5, IL-12(p40)) and interferon-gamma (IFN-gamma) in the sera of mice immunized with pBMC2 indicated high levels of IL-4 and IL-5, although there were also significant levels of IFN-gamma. Mice immunized with pBMC2 showed antigen-specific stimulation of splenocytes according to the incorporation of bromodeoxyuridine and IFN-gamma secretion. In all trials, mice injected intramuscularly with 50microg of pBMC2 presented the highest immune response. Moreover, cattle immunized with this DNA vaccine showed antibody production significantly different to the negative control. In conclusion, these results suggest the potential of DNA immunization with pBMC2 to induce humoral and cellular immune responses against B. microplus. 相似文献
636.
Canine parvovirus (CPV) has been reported throughout the world since the late 1970s. Published information was reviewed to draw insights into the epidemiology, pathogenesis, diagnosis, treatment and outcomes of CPV disease in Australia and the role of scientific research on CPV occurrence, with key research discoveries and knowledge gaps identified. Australian researchers contributed substantially to early findings, including the first reported cases of parvoviral myocarditis, investigations into disease aetiopathogenesis, host and environmental risk factors and links between CPV and feline panleukopenia. Two of the world's first CPV serological surveys were conducted in Australia and a 1980 national veterinary survey of Australian and New Zealand dogs revealed 6824 suspected CPV cases and 1058 deaths. In 2010, an Australian national disease surveillance system was launched; 4940 CPV cases were reported between 2009 and 2014, although underreporting was likely. A 2017 study estimated national incidence to be 4.12 cases per 1000 dogs, and an annual case load of 20,110 based on 4219 CPV case reports in a survey of all Australian veterinary clinics, with a 23.5% response rate. CPV disease risk factors identified included socioeconomic disadvantage, geographical location (rural/remote), season (summer) and rainfall (recent rain and longer dry periods both increasing risk). Age <16 weeks was identified as a risk factor for vaccination failure. Important knowledge gaps exist regarding national canine and feline demographic and CPV case data, vaccination coverage and population immunity, CPV transmission between owned dogs and other carnivore populations in Australia and the most effective methods to control epizootics. 相似文献
637.
Lucciana Recchi Silvana Alvariza Alejandro Benech Natalie Ruiz María José Estradé Gonzalo Suarez Nadia Crosignani 《Journal of veterinary pharmacology and therapeutics》2020,43(4):381-384
The purpose of this study was to evaluate the pharmacokinetics of oral amitriptyline in horses. Oral amitriptyline (1 mg/kg) was administered to six horses. Blood samples were collected from jugular and lateral thoracic vein at predetermined times from 0 to 24 hr after administration. Plasma concentrations were determined by high-performance liquid chromatography and analyzed using noncompartmental methods. Pharmacodynamic parameters including heart rate, respiration rate, and intestinal motility were evaluated, and electrocardiographic examinations were performed in all subjects. The mean maximum plasma concentration (Cmax) of amitriptyline was 30.7 ng/ml, time to maximum plasma concentration (Tmax) 1–2 hr, elimination half-life (t1/2) 17.2 hr, area under plasma concentration–time curve (AUC) 487.4 ng ml−1 hr−1, apparent clearance (Cl/F) 2.6 L hr−1 kg−1, and apparent volume of distribution (Vd/F) 60.1 L/kg. Jugular vein sampling overestimated the amount of amitriptyline absorbed and should not be used to study uptake following oral administration. Heart rate and intestinal motility showed significant variation (p < .05). Electrocardiography did not provide conclusive results. Further studies are required to discern if multiple dose treatment would take the drug to steady state as expected, consequently increasing plasma concentrations. 相似文献
638.
Chase SC Ruiz RD Münch G Neugebauer G Schroeder M Trafton LM 《Science (New York, N.Y.)》1974,183(4122):315-317
Thermal maps of Jupiter at 20 and 40 micrometers show structure closely related to the visual appearance of the planet. Peak brightness temperatures of 126 degrees and 145 degrees K have been measured on the South Equatorial Belt, for the 20- and 40-micrometer channels, respectively. Corresponding values for the South Tropical Zone are 120 degrees and 138 degrees K. No asymmetries between the illuminated sunlit and nonilluminated parts of the disk were found. A preliminary discussion of the data, in terms of simple radiative equilibrium models, is presented. The net thermal energy of the planet as a whole is twice the solar energy input. 相似文献
639.
Although ordinary chondrite (OC) meteorites dominate observed falls, the identification of near-Earth and main-belt asteroid sources has remained elusive. Telescopic measurements of 35 near-Earth asteroids ( approximately3 kilometers in diameter) revealed six that have visible wavelength spectra similar to laboratory spectra of OC meteorites. Near-Earth asteroids were found to have spectral properties that span the range between the previously separated domains of OC meteorites and the most common (S class) asteroids, suggesting a link. This range of spectral properties could arise through a diversity of mineralogies and regolith particle sizes, as well as through a time-dependent surface weathering process. 相似文献
640.
The water balance of drip irrigated apricot trees (Prunus armeniaca L. cv. Búlida grafted onto “Realfino” apricot rootstock) was determined during a 30-month-period. Two irrigation regimes based on the reduction coefficients of Class A pan evaporation (1 and 0.5) were used to determine the water consumed. The water balance parameters for these treatments are shown and discussed in detail. Overall, the trees receiving less water showed 35% less evapotranspiration. Crop coefficients calculated on the basis of the water balance over a 30-month-period led to a saving of almost 14% water, since the coefficients were slightly below those used in other apricot orchards in the same area. 相似文献