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排序方式: 共有120条查询结果,搜索用时 15 毫秒
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Galvez J de Souza Gracioso J Camuesco D Galvez J Vilegas W Monteiro Souza Brito AR Zarzuelo A 《Fitoterapia》2006,77(7-8):515-520
Turnera ulmifolia is a plant popularly known in Brazil and South America as chanana. Some species of Turnera are widely used in folk medicine for different types of inflammatory diseases. In this study, the preventive intestinal antiinflammatory activity of a lyophilized infusion obtained from the aerial parts of T. ulmifolia was tested in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis. The results obtained revealed that pretreatment to colitic rats with the extract, at 250 and 500 mg/kg, significantly attenuated the colonic damage induced by TNBS. This beneficial effect was associated with an improvement in the colonic oxidative status, since the infusion prevented the glutathione depletion that occurred as a consequence of the colonic inflammation. On the other hand, this antioxidant activity was confirmed in in vitro studies. In conclusion, the preventive effect exerted by the lyophilized infusion of T. ulmifolia in the TNBS model of rat colitis is probably related to its antioxidant properties, due to its flavonoids content. 相似文献
3.
Anadón A Martínez MA Martínez M Ríos A Caballero V Ares I Martínez-Larrañaga MR 《Journal of agricultural and food chemistry》2008,56(22):11049-11056
Chickens were used to investigate plasma disposition of florfenicol after single intravenous (i.v.) and oral dose (20 mg kg-1 body weight) and to study residue depletion of florfenicol and its major metabolite florfenicol-amine after multiple oral doses (40 mg kg-1 body weight, daily for 3 days). Plasma and tissue samples were analyzed using a high-performance liquid chromatography (HPLC) method. After i.v. and oral administration, plasma concentration-time curves were best described by a two-compartment open model. The mean [ +/- standard deviation (SD)] elimination half-life (t1/2beta) of florfenicol in plasma was 7.90 +/- 0.48 and 8.34 +/- 0.64 h after i.v. and oral administration, respectively. The maximum plasma concentration was 10.23 +/- 1.67 microg mL-1, and the interval from oral administration until maximal concentration was 0.63 +/- 0.07 h. Oral bioavailability was found to be 87 +/- 16%. Florfenicol was converted to florfenicol-amine. After multiple oral dose (40 mg kg-1 body weight, daily for 3 days), in kidney and liver, concentrations of florfenicol (119.34 +/- 31.81 and 817.34 +/- 91.65 microg kg-1, respectively) and florfenicol-amine (60.67 +/- 13.05 and 48.50 +/- 13.07 microg kg-1, respectively) persisted for 7 days. The prolonged presence of residues of florfenicol and florfenicol-amine in edible tissues can play an important role in human food safety, because the compounds could give rise to a possible health risk. A withdrawal time of 6 days was necessary to ensure that the residues of florfenicol were less than the maximal residue limits or tolerance established by the European Union. 相似文献
4.
Cabras P Farris GA Pinna MV Pusino A 《Journal of agricultural and food chemistry》2004,52(26):8053-8056
The fungicide fenhexamid [N-(2,3-dichloro-4-hydroxyphenyl)-1-methylcyclohexanecarboxamide] degraded rapidly by UV or sunlight irradiation, yielding 7-chloro-6-hydroxy-2-(1-methylcyclohexyl)-1,3-benzoxazole (CHB) as a main photoproduct. CHB was isolated, and its effect on alcoholic fermentation of Saccharomyces cerevisiae was studied. The results indicate that the presence of CHB does not affect the extent of alcohol production. After 12 days, the amount of CHB in the fermentation medium decreased by ca. 65%. Only 25% of the missing CHB was recovered unchanged from yeasts, most likely because it was adsorbed on the yeast wall cell. The remaining part degraded during the fermentation process. Glucan and chitin, two potential adsorbents, which constitute yeast cell walls, exhibited affinity for CHB. 相似文献
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José M. Molleda Isabel Cervantes Alba Galán Rodrigo Tardón† José M. Gallardo‡ Eva M. Martín-Suárez 《Veterinary ophthalmology》2008,11(S1):2-7
Purpose: To describe the protocol and appearance of fluorescein angiography (FA) in normal horses.
Animals: A total of 25 healthy horses aged between 5 and 15 years.
Materials and Methods: The horses were sedated with 15 µg/kg detomidine and 50 µg/kg butorphanol and dilated with topical tropicamide 1%. All angiograms were recorded after intravenous bolus injection of 10 mg/kg of fluorescein sodium solution.
Results: Two successive angiographic phases could be discerned: the choriopapillary phase, starting at 46.95 ± 9.48 s, and the retinal vascular phase, starting at 47.79 ± 10.38 s. The retinal vascular phase was divided in three parts: filling phase , maximum fluorescence point , and fading phase . During the filling phase, the dye progressed into the retinal vessels, obtaining maximum fluorescence at 59.79 ± 10.39 s, termed the maximum fluorescence point. The fading phase started immediately following the maximum fluorescence point. During this phase, vascular fluorescence decreased to complete reduction at 74.76 ± 9.81 s. Also, areas of delayed choroidal filling, the presence of short retinal vessels in the ventral region of the optic disc, and a particular filling of the optic disc were also observed.
Conclusions: The normal angiographic sequence was described in horses. FA may be a useful method for studying the integrity of the blood–retinal barriers in horses. 相似文献
Animals: A total of 25 healthy horses aged between 5 and 15 years.
Materials and Methods: The horses were sedated with 15 µg/kg detomidine and 50 µg/kg butorphanol and dilated with topical tropicamide 1%. All angiograms were recorded after intravenous bolus injection of 10 mg/kg of fluorescein sodium solution.
Results: Two successive angiographic phases could be discerned: the choriopapillary phase, starting at 46.95 ± 9.48 s, and the retinal vascular phase, starting at 47.79 ± 10.38 s. The retinal vascular phase was divided in three parts: filling phase , maximum fluorescence point , and fading phase . During the filling phase, the dye progressed into the retinal vessels, obtaining maximum fluorescence at 59.79 ± 10.39 s, termed the maximum fluorescence point. The fading phase started immediately following the maximum fluorescence point. During this phase, vascular fluorescence decreased to complete reduction at 74.76 ± 9.81 s. Also, areas of delayed choroidal filling, the presence of short retinal vessels in the ventral region of the optic disc, and a particular filling of the optic disc were also observed.
Conclusions: The normal angiographic sequence was described in horses. FA may be a useful method for studying the integrity of the blood–retinal barriers in horses. 相似文献
7.
S Martín Rillo C de Alba Romero A Romero Rodriguez R Cidoncha & AJ Ziecik 《Reproduction in domestic animals》2001,36(6):297-300
As in other species, the reproductive tract in pigs increases in size with age and body weight, and the development of the reproductive tract depends on a balance between development of the pituitary–ovarian axis and the influence of metabolic hormones. Two experiments were conducted in prepubertal Duroc gilts, 150–180 days of age, to determine whether litter size is related to vaginal–cervix catheter penetration length during insemination. In experiment 1, oestrus was induced in 452 gilts with a combined dose of 400 IU Pregnant Mare Serum Gonadotrophine (PMSG) + 200 IU human chorionic gonadotropin (hCG). The gilts were classified into three catheter penetration length groups: Ih, ≤ 21 cm; IIh, > 21 and < 28 cm; IIIh, > 28 cm. The litter size was lowest in group Ih (7.35 ± 0.15) compared with groups IIh (7.81 ± 0.12; p < 0.05) and IIIh (10.0 ± 0.36; p < 0.001). In experiment 2, first oestrus was induced in 162 gilts by boar exposure. The gilts were classified into three catheter penetration length groups at insemination during their second oestrus: In, ≤ 24 cm; IIn, > 24 and < 26 cm; IIIn, > 26 cm. As in experiment 1, the litter size was lowest in the group with the shortest catheter penetration length (8.32 ± 0.19). The litter size was not different among gilts of groups IIn and IIIn (8.84 ± 0.35 and 9.56 ± 0.46, respectively), but litter size was lower (p < 0.05) in group In than in group IIn. Based on the combined data from both experiments, the correlation between the catheter penetration length and total number of piglets born was expressed as: y=5.346 ± 0.104x; r=0.361 (p < 0.05). Fertility rate was not different among the groups of gilts induced into oestrus by hormone treatment or inseminated in the second oestrus; however, the total fertility rate of boar‐exposed gilts was higher (p < 0.0001) than PMSG/hCG treated animals. Thus, it is possible to conclude that litter size at first farrowing is associated with vaginal–cervix catheter penetration length during insemination of the gilt. 相似文献
8.
Experiments, carried out to verify the parasitic action of Helicotylenchus digonicus on Pinus strobus and P. excelsa and their hybrid, indicate a positive host-parasite relationship. In general the consequences of nematode feeding is a reduction of seedling development similar to that induced by the absence of mycorrhizae. 相似文献
9.
Allepuz A Casal J Napp S Saez M Alba A Vilar M Domingo M González MA Duran-Ferrer M Vicente J Alvarez J Muñoz M Saez JL 《Preventive veterinary medicine》2011,100(1):441-52
In this study we explored the spatial variation of Bovine tuberculosis (BTB) risk of being positive, new positive or persistently positive, as well as the risk of eliminating BTB in positive herds throughout Spain from 2006 to 2009 by means of hierarchical Bayesian models. The results of the models showed that the risk of infection (positive or new positive herds), persistence and elimination was lower in counties located in north and north-eastern of Spain, and in the Balearic and Canary islands than in the rest of the country. In some counties the risk of positivity was high during the four years of study, whereas there were others where the risk of positivity was high only in some of the years. With regard to the risk of persistence of BTB positive herds, counties located in the central, western and south-western part of the country had a higher risk in the three studied periods. This study has identified some specific areas of increased BTB risk in Spain, information that is useful for disease management. 相似文献
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