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排序方式: 共有490条查询结果,搜索用时 203 毫秒
91.
Letizia M. Davi Massimo Baldi Luciano Penazzi Michelina Liboni 《Pest management science》1992,35(1):63-67
The purpose of this work was to compare the method and analytical results obtained by liquid/liquid extraction with those of solid-phase extraction, in particular with the use of an Empore disc, in the investigation of pesticide residues in drinking water. 相似文献
92.
93.
Geovane R. Oliveira Willian K. Oliveira Carla Andrade Antonio Diego B. Melo Fernando B. Luciano Renata E. F. Macedo Leandro B. Costa 《Journal of animal physiology and animal nutrition》2019,103(3):756-765
This study evaluated the antimicrobial effect of essential oils (EO) and organic acids (OA) against Salmonella Enteritidis in chicken feed and during an in vitro model that mimics the chicken digestive process. The minimal inhibitory concentration (MIC) of allyl isothiocyanate (AITC), carvacrol (CV), propionic acid (PROP) and caproic acid (CAP) were individually determined. Then, based on the MICs of each compound, combinations of EOs and/or OAs were tested to evaluate their synergic antimicrobial effect. The synergic effect of AITC and CAP was the most efficient against the bacterial strain tested. Commercial feed was inoculated with a 5‐strain cocktail of S. Enteritidis and treated with different doses of AITC + CAP to evaluate their effect on the growth/survival of the pathogen. In addition, the simulated digestion model was used to access the antimicrobial effect of AITC + CAP added to the feed towards S. Enteritidis and Lactobacillus plantarum. Synergistic effect was found between AITC (0.065 mM) and CAP (17.5 mM) against S. Enteritidis in chicken feed, where S. Enteritidis was reduced to undetectable levels (<1.00 log CFU/g). AITC (1.95 mM) + CAP (45 mM) also decreased (p < 0.05) the population of S. Enteritidis in the simulated digestion, while the growth of L. plantarum was not affected. Therefore, the addition of AITC + CAP in feed might be a potential natural antimicrobial able to prevent economic losses caused for Salmonella in chicken. 相似文献
94.
Laura Guadalupe Grtter Luciano Cattaneo Patricia Estela Marini Michael E. Kjelland Luis B. Ferr 《Reproduction in domestic animals》2019,54(4):655-665
Sperm cryopreservation facilitates the storage and transport of germplasm for its use in artificial insemination (AI) and other advanced reproductive technologies. The cryopreservation process can damage sperm and compromise functionality. Several cryobiological studies have found that the physical and biological factors that affect sperm survival at low temperatures during the cryopreservation process often involve the integrity of sperm membrane. In this review, the behaviour of the sperm membrane against cooling, cold shock, ice crystal formation, oxidative stress, osmotic changes, reorganization of the lipid bilayer and addition of cryoprotective agents (CPA) is discussed. In addition, the phenomenon of reactive oxygen species (ROS) and its relationship with the cryopreservation process is also described. Semen cryopreservation techniques have progressed slowly in past years, and the current performance, measured as post‐thawed survival, is not very different compared to past decades. Recent advances in understanding the structure of the cell membrane, its function and metabolism have driven to new conservation systems, including lyophilization and vitrification. However, none of these technologies is commercially available, although its future appears very promising. 相似文献
95.
Katiuska Satu Esterina Fazio Adriana Ferlazzo Pietro Medica 《Reproduction in domestic animals》2019,54(10):1411-1418
The hypothesis that a local serotonergic network might also exist in the follicle of mares remains poorly documented, with exception for humans and laboratory species. For this reason, the aim of the present study was to clarify this possibility, investigating intrafollicular serotonin concentrations of the cycling mare at ovulation time. Sixty ovaries collected from 30 clinically healthy mares of slaughterhouse meat production with clinically normal reproductive tracts after slaughtering were evaluated. Blood samples were taken prior to sacrifice. Follicles were classified in three categories in relation to size, as small (20–30 mm), medium (31–40 mm) and large (>41 mm), and the follicular fluid samples were extracted from each follicle. Intrafollicular and systemic serotonin (5‐HT), oestradiol‐17β (E2) and progesterone (P4) were determined by means of enzyme‐linked immunosorbent assay and RIA, respectively. Intrafollicular 5‐HT, E2 and P4 concentrations were higher than systemic ones (p < .05). 5‐HT concentrations increased in larger compared to medium follicles, without differences compared to small size follicles (p < .05). 5‐HT and E2 (r = .79) and 5‐HT and P4 (r = .79; p < .05) were positively correlated. 5‐HT and P4 concentrations in follicular fluid increased progressively with the increase in follicular size (p < .05). Follicle diameter and E2 (r = .85) and P4 (r = .68) were correlated (p < .05). Since serotonin interacts with steroids, its role on steroidogenesis during growth of the dominant follicle may be suggested. 相似文献
96.
Suyane Nayara Garcia Socoloski Bruno Gomes de Castro Matheus Dias Cordeiro Adivaldo Henrique da Fonseca Marcio Barizon Cepeda Rafael Romero Nicolino Luciano Bastos Lopes 《Tropical animal health and production》2018,50(4):831-836
Borrelia burgdorferi sensu stricto is the main etiological agent of Lyme disease (LD) in the USA. In Brazil, it is believed that a similar spirochete is the causal agent of the Baggio–Yoshinari syndrome (BYS), a zoonosis also transmitted by ticks, whose clinical manifestations are similar to those of LD. Despite the epidemiological importance, there are no studies reporting the presence and the prevalence of B. burgdorferi among horses in Mato Grosso State. The aim of this study was to detect and measure the frequency of IgG antibodies anti-B. burgdorferi American strain G39/40 in horses in the municipality of Sinop, MT—Brazil, using the indirect enzyme-linked immunosorbent assay (ELISA) for serological diagnosis. Blood samples from 367 horses were collected in 81 farms. An epidemiological questionnaire was applied during the visits to obtain information related to the animals and the farms. From the 367 horses, 214 were positive for B. burgdorferi sensu stricto according to the results of the ELISA test, representing an apparent prevalence of 54.04% [CI?=?0.4548051–0.6237234]. Concomitantly, 89 blood samples were taken for molecular analysis by nested polymerase chain reaction (PCR). According to the PCR test results, none of the samples were reactive, although 53 of these samples were reactive according to ELISA. Seventy five farms (92.59%) had at least one reactive horse for B. burgdorferi. Our results support the hypothesis of the presence of anti-Borrelia spp. antibodies in horses in Mato Grosso, reaching a high animal prevalence. Besides that, leisure/sport purposes proved to be a risk factor, with an odds ratio of 3.16. These findings clearly indicate the need of borreliosis control in Sinop and make a significant contribution to the knowledge of the disease in Mato Grosso. 相似文献
97.
Orfanos P Naska A Trichopoulos D Slimani N Ferrari P van Bakel M Deharveng G Overvad K Tjønneland A Halkjaer J Santucci de Magistris M Tumino R Pala V Sacerdote C Masala G Skeie G Engeset D Lund E Jakszyn P Barricarte A Chirlaque MD Martinez-Garcia C Amiano P Quirós JR Bingham S Welch A Spencer EA Key TJ Rohrmann S Linseisen J Ray J Boeing H Peeters PH Bueno-de-Mesquita HB Ocke M Johansson I Johansson G Berglund G Manjer J Boutron-Ruault MC Touvier M Clavel-Chapelon F Trichopoulou A 《Public health nutrition》2007,10(12):1515-1525
98.
Bamia C Trichopoulos D Ferrari P Overvad K Bjerregaard L Tjønneland A Halkjaer J Clavel-Chapelon F Kesse E Boutron-Ruault MC Boffetta P Nagel G Linseisen J Boeing H Hoffmann K Kasapa C Orfanou A Travezea C Slimani N Norat T Palli D Pala V Panico S Tumino R Sacerdote C Bueno-de-Mesquita HB Waijers PM Peeters PH van der Schouw YT Berenguer A Martinez-Garcia C Navarro C Barricarte A Dorronsoro M Berglund G Wirfält E Johansson I Johansson G Bingham S Khaw KT Spencer EA Key T Riboli E Trichopoulou A 《Public health nutrition》2007,10(6):590-598
99.
Marotti I Bonetti A Biavati B Catizone P Dinelli G 《Journal of agricultural and food chemistry》2007,55(10):3913-3919
Bifidobacteria strains from human origin were screened for the specific activity (beta-glucosidase activity) involved in the metabolism of dietary flavonoids. Five strains with high beta-glucosidase activity were selected for further metabolism analyses (high-performance liquid chromatography separations) of flavonoid glycosides occurring in Phaseolus vulgaris L. (common bean) seeds and seedlings. All selected strains were found to be active in the conversion of kaempferol 3-O-glucoside, daidzin, genistin, and glycitin into their aglyconic forms. No metabolites were detected after the fermentation tests with the diglucosidic compound kaempferol 3-O-xylosylglucoside. In addition, to verify the effective bioavailability of flavonoid aglycones, the degradation rates of daidzein, genistein, glycitein, and kaempferol, following incubation with selected strains, were monitored. The results showed that the five selected strains of bifidobacteria, being active in the biotranformation of flavonoid glycosides occurring in common bean seeds and seedlings, could be considered as probiotic dietary adjuncts to improve the nutritional and health properties of flavonoid-based products, comprising hypothetical common bean food derivatives. 相似文献
100.
Fontanini D Capocchi A Muccilli V Saviozzi F Cunsolo V Saletti R Foti S Galleschi L 《Journal of agricultural and food chemistry》2007,55(25):10452-10460
The proteins belonging to the cereal trypsin/alpha-amylase inhibitor family are abundant water/salt-soluble flour proteins active against alpha-amylases from several seed parasites and pests and inactive against endogenous alpha-amylases. Three alpha-amylase inhibitor families have been described in cereals that vary in size and are differently expressed among Triticeae seeds. The present work investigates the presence of human salivary alpha-amylase inhibitors in emmer (Triticum dicoccon Schrank) flour. The isolation was obtained by a series of chromatography steps, and the purification progress was monitored through the inhibition of human salivary alpha-amylase activity. The purified fraction was subjected to protein sequencing by tandem mass spectrometry (MSMS) of the tryptic digests obtained after the sample separation on 2-DE. MSMS data indicated that the emmer alpha-amylase inhibitory fraction was composed of two newly identified proteins [emmer dimeric inhibitor 1 (EDI-1) and emmer dimeric inhibitor 2 (EDI-2)] sharing very high identity levels with related proteins from Triticum aestivum. 相似文献