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171.
172.
Ediane Batista da Silva Bruna Daniella de Souza Silva Jerônimo Rafael Ruiz Leon André Kipnis Isabel K.F. de Miranda Santos Ana Paula Junqueira-Kipnis 《Veterinary journal (London, England : 1997)》2011,187(2):276-278
This study evaluated the Mycobacterium tuberculosis protein antigen MPT-51, the trimeric antigen 85 (Ag85) complex, and Bacillus Calmette-Guérin (BCG) in an indirect ELISA to diagnose bovine tuberculosis (TB) from serum samples. Serum was collected from 208 intra-dermal tuberculin test (ITT)-positive and 54 ITT-negative animals from a region where bovine TB is endemic. Using the Ag85 and BCG antigens, the indirect ELISA was able to discriminate ITT-positive from ITT-negative animals. This level of discrimination was not achieved when using the MPT-51 antigen. The highest sensitivity (Se) and specificity (Sp) of the test was found when BCG was used (Se, 82%; Sp, 91%). Further work in different epidemiological settings and with larger numbers of animals will be required to validate these findings. 相似文献
173.
Objective To compare intraocular pressure (IOP) measurements made on healthy adult rabbits without the effect of tranquilizers using the new applanation tonometer, Tono‐Pen Avia®, and the rebound tonometer Tonovet®. Methods Intraocular pressure was measured throughout the day (6:00, 9:00, 12:00, 15:00, and 18:00 h) in 38 adult New Zealand White rabbits (76 eyes). The animals were 20 males and 18 females, with a mean weight of 3.5 kg and an average age of 6 months. A complete ocular exam (including Schirmer tear test, fluorescein staining, slit‐lamp biomicroscopy, and direct ophthalmoscopy) was performed on all animals at the beginning of the trial. Rebound tonometry was performed, and after 10 min, anesthetic drops were instilled and applanation tonometry was carried out. IOP values obtained using the two techniques were analyzed statistically. Results The mean IOP was 9.51 ± 2.62 mmHg with Tonovet®, and 15.44 ± 2.16 mmHg with the Tono‐Pen Avia®. Significant differences between measurements with the two tonometers were observed (P < 0.001). The linear regression equation describing the relationship between the two tonometers was y = 0.4923x + 10.754 (y = Tonovet® and x = Tono‐Pen Avia®). High IOPs were recorded in the early measurements (6:00), but the average IOPs from both devices were statistically similar throughout the day (P = 0.086). The correlation coefficient was r2 = 0.357. No significant difference in IOP regarding gender was observed. Conclusion The Tono‐Pen Avia® recorded higher levels of IOP compared with the Tonovet®. Early in the day, the IOP of rabbits was higher than later in the day, regardless of the tonometer used. 相似文献
174.
Blanco PG Tórtora M Rodríguez R Arias DO Gobello C 《Veterinary journal (London, England : 1997)》2011,190(1):154-159
The aim of this study was to describe changes in cardiac morphology, systolic function and some peripheral hemodynamic parameters during normal pregnancy in dogs. Twenty healthy bitches, 10 pregnant (PG) and 10 non-pregnant controls (CG), were evaluated every 10 days using echocardiography from day 0 of the estrus cycle to parturition or to day 65 for the PG and CG groups, respectively. Systolic blood pressure (SBP) and uterine artery resistance index (RI) were also assessed. Throughout the study, the shortening fraction and cardiac output increased up to 30% vs. 5% (P<0.01) and 45% vs. 2% (P<0.01) in the PG and CG groups, respectively. In contrast, SBP and RI diminished up to 20% vs. 1% (P<0.01) and 29% vs. 0% (P<0.01) in the PG and CG groups, respectively. In conclusion, a decrease in afterload, an increase in cardiac output and cardiac hypertrophy appear to be the result of the hemodynamic modifications occurring during pregnancy in dogs. 相似文献
175.
Rosanna S. Valitutto Silvia M. Sella Emmanoel V. Silva-Filho Roberto Guimarães Pereira Norbert Miekeley 《Water, air, and soil pollution》2007,178(1-4):89-102
Aquatic macrophytes are well known accumulators for heavy metals, the reason why they are used as bioindicators for water quality and in phytoremediaton strategies. This study reports on the elemental concentrations in four free-floating aquatic macrophytes (S. auriculata; P. stratiotes; E. crassipes and E. azurea) growing in two water reservoirs (Santana e Vigário, Rio de Janeiro State, Brazil) of an electric power plant that receive input from the polluted Paraíba do Sul River. Filtered water samples and water suspended solids from these environments were also analysed. Inductively coupled plasma mass spectrometry was used as the principal method, allowing the determination of up to 41 elements, including the rare-earth elements (REEs) and other trace metals not assayed before in these macrophytes. The results show that all elements studied are accumulated by the macrophytes with concentration ratios (CR = [plant]: [water]) varying from about 1,000 to 200,000, based on the dry weight of the plant species. With a few exceptions, highest accumulations were observed in E. crassipes in which CRs increase in the sequence: Cu < Mo < Cr < Pb < Tl < Fe < La < Zn < Ce< Mn. Surprisingly high CRs (e.g. Ce: 74,000) and corresponding mass concentrations were observed for the rare-earth elements (e.g. ∑REE: 112 mg kg?1), also measured in the water suspended particle fraction. The results show that this fraction acts as an effective sink for trace metals in the aquatic system studied and seems to play also an important role in the transfer of metals from water to the plant species. 相似文献
176.
A catena developed on gabbro in Galicia, N.W. Spain, was studied. The methods utilized, consisting of macro- and microscopic mineralogical and morphological observation, allowed the identification of different features produced by the action of pedological and geomorphological processes. The application of Butler's K cycle concept allows a relative sequence of events to be established in which pedogenetic processes are integrated within the general framework of the evolutionary history of the slope. Five K cycles could be recognized, beginning with a phase of deep weathering and ending with the present phase of incipient soil formation. In between feature a.o. phases of solifluxion, the formation of an argillic horizon and the development of a stoneline. 相似文献
177.
Cerdá B Periago P Espín JC Tomás-Barberán FA 《Journal of agricultural and food chemistry》2005,53(14):5571-5576
Dietary ellagic acid and related polyphenols are metabolized in humans to dibenzopyran-6-one derivatives, and the microbial origin of these metabolites has been suggested. However, this has not been demonstrated so far. Fecal samples donated by six volunteers were incubated under anaerobic conditions, and aliquots were used to evaluate the fecal metabolism of ellagic acid, the ellagitannin punicalagin, and an ellagitannin rich extract from walnuts. The isoflavone daidzein was also incubated with the same fecal samples to follow the production of the microbial metabolites previously reported (dihydrogenistein, O-demethylangolensin, and equol) as a positive control of the system and to evaluate similarities between isoflavone and ellagic acid fecal flora metabolism. After fermentation the metabolite "urolithin A" (3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one) was produced from ellagic acid, punicalagin, and the ellagitannin extract in all the fecal cultures from different volunteers, but with very different production rates and concentrations. This large variability in the concentration of metabolite and kinetics of metabolite production is consistent with the large variability found in the excretion of these metabolites in urine in vivo after human consumption of ellagitannins, and with differences in the composition of the fecal microflora. No correlation between isoflavone and ellagic acid metabolism by fecal microflora was observed. The present study confirms the microbial origin of the recently reported in vivo generated hydroxy-6H-dibenzo[b,d]pyran-6-one derivatives in humans and is a further step in the study of the bioavailability and metabolism of ellagic acid and ellagitannins. 相似文献
178.
179.
Patrícia Valent?o Paula B Andrade Eurico Silva Ana Vicente Henrique Santos M Lourdes Bastos Rosa M Seabra 《Journal of agricultural and food chemistry》2002,50(3):460-463
In the course of a phytochemical study of the bitter tonic plant, small centaury (Centaurium erythraea), six methoxylated xanthones (1,5-hydroxy-3-methoxyxanthone, 1-hydroxy-3,5,6-trimethoxyxanthone, 1-hydroxy-3,5,6,7-tetramethoxyxanthone, 1-hydroxy-3,5,6,7,8-pentamethoxyxanthone, 1-hydroxy-3,7,8-trimethoxyxanthone and 1,8-dihydroxy-3,5,6,7-tetramethoxyxanthone) were isolated and identified by spectroscopic means (nuclear magnetic resonance, mass spectroscopy, and UV). Subsequently, a high-performance liquid chromatography/diode array detection method was developed for the determination of these and other methoxylated xanthones occurring in the chloroform extract of small centaury aerial parts. The methodology developed was applied to twelve samples, and in all of them, nine xanthones were identified and quantified. This methodology can be considered complimentary to the one proposed by the European Pharmacopoeia. 相似文献
180.
Gil A De La Fuente EB Lenardis AE López Pereira M Suárez SA Bandoni A Van Baren C Di Leo Lira P Ghersa CM 《Journal of agricultural and food chemistry》2002,50(10):2870-2877
The objective was to study the essential oil composition of coriander fruits in plants growing in environments differing in soil conditions and weediness level. Factorial field experiments were conducted in two locations from the Rolling Pampas, Argentina, and two coriander landraces (European and Argentinean) were tested under two levels of nitrogen fertilization and weediness. Data were evaluated with uni- and multivariate techniques. The variation in the oil composition was related to the relative proportion of the constituents and not to the presence/absence of a particular component. Weather conditions in 1997 favored linalool and camphor in both landraces. Location, fertilization, and weediness also affected the chemical profile. The European landrace showed a more stable concentration of the major components than the Argentinean landrace. These results, which show the relationships between some environmental conditions and the essential oil composition, are useful in the development of innovative strategies aimed to improve oil composition and to manage crop pests. 相似文献