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21.
The present work evaluated the chemical composition of the essential oils (EO) obtained from Lippia origanoides and their DNA protective effect against bleomycin-induced genotoxicity. L. origanoides EO chemical composition was determined by gas chromatography–mass spectrometry (GC–MS). The major compounds of the L. origanoides EOs were thymol (34–58%) and carvacrol (26%). The antigenotoxic effects of the EOs, major compounds and standard compound (epigallocatechin gallate) were assayed in co-incubation procedures using the SOS chromotest in Escherichia coli. Both EOs and their major compounds protected bacterial cells against bleomycin-induced genotoxicity indicating that these two compounds were principally responsible for the antigenotoxicity detected in the oils. Thymol and carvacrol antigenotoxicity was lower than those observed with epigallocatechin gallate. The results were discussed in relation to the chemopreventive potential of L. origanoides EOs and their major components, carvacrol and thymol. 相似文献
22.
Milián-Suazo F Banda-Ruíz V Ramírez-Casillas C Arriaga-Díaz C 《Preventive veterinary medicine》2002,55(4):e129-264
The spacer oligonucleotide typing (spoligotyping) method was used to differentiate 62 Mycobacterium bovis isolates obtained from tissues with macroscopic lesions typical of tuberculosis in dairy cattle from different regions of Mexico. Our purpose was to see if a strain from one region was genetically different from those of other regions (with the long-term aim of doing molecular trace back of isolates obtained in the laboratory). Results from the genetic analysis indicate that M. bovis isolates cannot be grouped by geographic location due to a wide range of genetic types involved in dairy cattle infections. Isolates even from the same herd showed different spoligotypes but some isolates from different region had similar genetic patterns. Genetic typing without epidemiologic information does not seem to be a plausible method to trace back animals to source of origin to detect and eliminate sources of infection. 相似文献
23.
Salceda Fernández-Barredo Carolina Galiana Angel García Santiago Vega María Teresa Gómez María Teresa Pérez-Gracia 《Journal of veterinary diagnostic investigation》2006,18(5):462-465
The aim of this study was to determine at which production stages hepatitis E virus (HEV) is shed by the highest number of pigs and to estimate the relative risk associated with each stage. For this purpose, 146 fecal samples of pigs from 21 farms were studied. In addition, 1 sample from the manure ditch and another sample of drinking water, collected directly from the trough located in the pen, were taken from 16 farms. HEV RNA was detected in fecal samples from 34 pigs (23.29%). The production stages in which most pigs excreted HEV were weaners (41.7%) and pigs in the first month of feeding (60%). The results of the statistical analysis showed that the principal significant risk stage in HEV shedding was the first month of feeding (odds ratio [OR] 19.5, 95% CI 3.59-106.07, P = 0.001) followed by the weaners stage (OR 9.3, 95% CI .78-48.42, P = 0.008). In 8 out of 16 farms tested (50%) HEV RNA was detected in raw manure and in the water trough of only 1. Detection of HEV in manure ditches raises the concern of how to deal with manure of swine origin, because it is used as soil fertilizer. 相似文献
24.
Carolina Naranjo Dolors Fondevila Marta Leiva Xavier Roura Teresa Pea 《Veterinary ophthalmology》2010,13(3):139-143
Objective Canine leishmaniosis is a disease characterized by the wide distribution of the parasite throughout the tissues of the host. The purpose of this study was to describe the presence of Leishmania spp. and associated inflammation in ocular‐associated muscles of dogs with patent leishmaniosis. Procedures Smooth muscles (iris dilator muscle, iris sphincter muscle, ciliary muscle, Müller muscle, smooth muscle of the periorbita and smooth muscle of the nictitating membrane) and striated muscles (orbicularis oculi muscle, obliquus dorsalis muscle and dorsal rectus muscle) were evaluated. Routine staining with hematoxylin and eosin and immunohistochemistry to detect Leishmania spp. were performed on tissue sections. Results Granulomatous inflammation was seen surrounding muscular fibers and was composed mainly of macrophages with scattered lymphocytes and plasma cells. This infiltrate could be seen in 52/473 (10.99%) samples of smooth muscle and 36/142 (25.35%) samples of striated muscle. Parasites were detected in 43/473 (9.09%) samples of smooth muscle and in 28/142 (19.71%) samples of striated muscle. Conclusions To the authors’ knowledge, this is the first report assessing the presence of Leishmania spp. and associated infiltrate in intraocular, extraocular and adnexal smooth and striated muscles. The inflammation present in those muscles could contribute to clinical signs already described, such as blepharitis, uveitis, and orbital cellulitis. 相似文献
25.
Silva Jos Hiago C. Saldanha Alan V. Carvalho Rayana M. R. Machado Carolina F. M. Flausino Bruno F. Antonio Adilson C. Gontijo Lessando M. 《Journal of pest science》2022,95(2):723-734
Journal of Pest Science - Increasing either inter- or intraspecific plant diversity has shown the potential to engender bottom-up and top-down effects upon herbivorous pests. Nonetheless, because... 相似文献
26.
Soliani Carolina Mattera Ma. Gabriela Marchelli Paula Azpilicueta Ma. Marta Dalla-Salda Guillermina 《European Journal of Forest Research》2021,140(5):1147-1161
European Journal of Forest Research - The resistance of different genotypes to abiotic stress may be due to genetic effects and/or to phenotypic plasticity allowing them to acclimate to variable... 相似文献
27.
Claudia S. Benimeli Analía Medina Carolina M. Navarro Roxana B. Medina María J. Amoroso María I. Gómez 《Water, air, and soil pollution》2010,210(1-4):365-370
In the present study, the growth and the Cu2+accumulation by roots, shoots and leaves of Zea mays were examined using copper sulphate in the range of 10?4 to 10?2 M. Plants of Z. mays did not show inhibition of growth in the presence of 10?4 to 10?2 M Cu2+; however, it was observed growth effects on root when different Cu2+ solution concentrations were used. Only the seedlings exposed to 10?2 M exhibited substantial root growth reduction, yielding only 56% of length with respect to the control. Seedlings exposed to 10?4 M Cu2+ exhibited 16% and 42% growth increase in shoots and leaves, respectively, when compared with the controls. The seedlings treated with 10?3 and 10?2 M Cu2+ were inhibited in shoot and leaf growth. The fresh weights in roots, shoots and leaves significantly decreased at 10?2 M Cu2+. The tolerance index, based on root length, was not significantly different for the three different treatments with copper. However, the total accumulation rate was very low at 10?4 and 10?3 M compared to 10?2 Cu treatments. The capacity of copper accumulation by roots, shoots and leaves of Z. mays plants increased concomitant to the copper concentration, arriving to 382 times more in roots, 157 in shoots and only 16 in leaves, all compared to the controls. Cu could be accumulated by roots, shoots and leaves when the initial concentrations were 10?3 and 10?4 M. However, when it was 10?2 M, the metal could not be accumulated by leaf and shoot levels; the roots could increase their copper accumulation capacity three times compared to the control. Z. mays has potential ability to accumulate Cu without being overly sensitive to Cu toxicity. 相似文献
28.
The aim of this study was to evaluate the chemical composition, energy and amino acid profile of dried salmon silage (DSS) for broilers. The DSS was obtained by acid digestion of salmon mortalities and subsequently co‐dried with wheat bran in a 70:30 ratio (70 parts silage and 30 parts wheat bran). Samples of DSS were evaluated for chemical composition, gross energy, nitrogen‐corrected true metabolizable energy (TMEn), mineral content, total and digestible amino acids for broilers, and amino acid score. The chemical composition of DSS was (mean ± SD): moisture (12.3 ± 0.8%), crude protein (44.0 ± 1.1%), ether extract (5.0 ± 2.4%), crude fiber (3.3 ± 0.4%) and ash (9.4 ± 0.6%). The gross energy and TMEn for broilers were 4 069 kcal/kg and 2 613 kcal/kg, respectively. The DSS mineral composition showed a high content of calcium (1.01%) and phosphorus (1.08%). The DSS had high levels of digestible methionine (0.74%), lysine (2.27%), and threonine (1.16%), and did not present limiting amino acids for broilers. Nutritional composition of DSS showed high protein content with an amino acid profile considered to be suitable as a protein source for broiler feeding. 相似文献
29.
30.
Alenza DP Arenas C Lopez ML Melian C 《Journal of the American Animal Hospital Association》2006,42(4):269-276
Trilostane is considered an efficacious and safe medication for canine pituitary-dependent hyperadrenocorticism (PDH). Its recommended frequency of administration is once daily. In this prospective study, the efficacy, toxicity, and long-term outcome of trilostane administered twice daily per os were evaluated in 44 dogs with PDH. Mean initial dose was 3.1 mg/kg q 12 hours, and mean final dose was 3.2 mg/kg q 12 hours. The final total daily dose was lower than previously reported for once-daily administration. The mean survival time for affected dogs was 930 days. 相似文献