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131.
Valentina Vitale Micaela Sgorbini Angela Briganti Michele Corazza Gloria Breghi Francesco Staffieri 《Journal of Equine Veterinary Science》2013
The purpose of this study was to evaluate changes in echocardiographic parameters during increasing infusion rates of dobutamine in isoflurane-anesthetized horses and to compare our results with those of previous studies. Six Standardbred female healthy horses were included in this study. All animals were anesthetized and infused with dobutamine at different rates. mean arterial pressure (MAP), heart rate (HR), and some echocardiographic measurements were recorded. Statistical analysis was applied. Under basal conditions (time 0 [T0]), HR ranged between 32 and 42 beats per minute (bpm), and MAP was between 39 and 63 mm Hg. MAP increased significantly from T0 compared with values at T2, T2, and T3 in a dose-dependent manner, while HR increased significantly only at T3 if compared to the other measuring times. Left ventricular internal diameter during diastole (LVDs) decreased significantly in a dose-dependent manner, with increasing of the infusion rate of dobutamine. Interventricular septal dimension during diastole (IVSs) increased significantly, and end-systole left ventricular volumes (LVVols) decreased significantly at T2 and T3 compared to T1. Ejection fraction (%) increased significantly between T0 and T1, T2, and T3. Cardiac output increased significantly only at the higher dosage (T3 vs. others) of dobutamine, but cardiac power output was enhanced significantly at T2 versus that at T0 and T1 and at T3 versus all the previous measurements. Arrhythmias were diagnosed in 5 of 6 (83.3%). In this study, the increase of MAP was found to be dose-dependent, according with literature. The HR and MAP values registered at T0 were comparable to previous results obtained both in anesthetized and conscious horses, while at T1, T2, and T3, HR and MAP values were similar only too those reported in anesthetized horses. IVSs increased and LVDs decreased significantly with the increment of dobutamine infusion rate. These findings suggest that dobutamine, even at low infusion rates, induces an enhancement in cardiac systolic function. The dose-dependent increase of IVSs and decrease of LVDs measurements are in line with those reported for dobutamine administered in conscious horses but with lower values. The LVVols dose-dependent reduction obtained in this study is in line with that in other reports, but both LVold and LVVols values after dobutamine infusion at different dosages are lower if compared to previous studies. The low LVol values and the wide standard deviation have influenced consequently the derived indices values (stroke volume [SV], EF, cardiac output [CO]). In the present study, SV did not significantly increase during dobutamine infusion. These results disagree with those reported by others. The increment of CO might be due mainly to the enhanced HR rather than to the weak changes of SV. Cardiac power output increased significantly from the 5 mcg/kg/min dosage in a dose-dependent manner, as reported by others. 相似文献
132.
Gloria Chan Abdolvahab Farzan Josepha DeLay Beverly McEwen John F. Prescott Robert M. Friendship 《Canadian journal of veterinary research》2013,77(4):254-260
Laboratory surveillance data from the Animal Health Laboratory, University of Guelph, on the etiological diagnoses of neonatal diarrhea in piglets were analyzed to determine the relative importance and trends of different enteric pathogens in Ontario. A total of 237 cases, including live and dead 1- to 7-day-old piglets, were submitted for diagnosis of gastrointestinal illness between 2001 and 2010. The combined frequencies for cases of gastrointestinal illness involving Escherichia coli, Clostridium perfringens type A, rotavirus, and Clostridium difficile, either as single pathogens or a complex of pathogens, accounted for 56% of the total cases. In a total of 33% of cases of gastrointestinal illness, an etiological agent was not identified. The frequency of cases diagnosed with enterotoxigenic E. coli was decreased from 2007. Cases submitted in 2010 were more likely to be diagnosed with C. perfringens type A compared to cases submitted in 2002 to 2007 (P < 0.05). There was a significant trend for cases submitted in the winter to be diagnosed with C. perfringens type A, enterotoxigenic E. coli, rotavirus, and Cystoisospora suis (formerly Isospora suis) (P < 0.05). Enterotoxigenic E. coli was less likely diagnosed if C. difficile, C. perfringens, or rotavirus were detected (P < 0.05). Younger piglets were more likely to be diagnosed with C. perfringens type A (P < 0.05) and C. difficile (P < 0.05) than older piglets. This study shows that E. coli, C. perfringens type A, rotavirus, and C. difficile are enteric pathogens of concern for Ontario swine farrowing operations and further research is required to understand the reasons for the cases that are not diagnosed. 相似文献
133.
Rodríguez-Alcalá LM García-Martínez MC Cachón F Marmesat S Alonso L Marquez-Ruiz G Fontecha J 《Journal of agricultural and food chemistry》2007,55(16):6533-6538
Changes in the lipid composition of two standard infant formulas induced by 4 years of storage were determined. Lipids were thoroughly analyzed using different gas-liquid and liquid-liquid chromatographic techniques. Oleic acid and linoleic acid, which accounted for almost the total monounsaturated and polyunsaturated fatty acids, respectively, showed slight but significant decreases (P < 0.05) during the 4 years of storage (from 41.52 to 39.83% for oleic acid and from 17.35 to 15.99% for linoleic acid). Total trans fatty acid isomers showed low initial level (0.22% of total fatty acids), and such level remained unchanged during the storage period. Nonvolatile oxidation compounds including oxidized, dimeric, and polymeric triglycerides did not significantly increase during the storage period, although a significant loss of tocopherols was found in the surface oil fraction (10-15%). In general, the results obtained indicate that, although small losses of oleic and linolenic acid as well as tocopherols were found, the 4 year storage period did not lead to relevant changes in the lipid fraction of infant formulas. 相似文献
134.
The in vitro activity of some isolated hydroxyanthracenones belonging to the genus Karwinskia against four bacteria, six filamentous fungi and four yeast are reported. These hydroxyanthracenones were found to possess antimicrobial activity, particularly against Streptococcus pyogenes, Candida albicans, C. boidinii, C. glabrata and Cryptococcus neoformans; minimal inhibitory concentrations range between 16 and 2 microg/ml. 相似文献
135.
Lolli M Bertelli D Plessi M Sabatini AG Restani C 《Journal of agricultural and food chemistry》2008,56(4):1298-1304
The importance of honey has been recently increased because of its nutrient and therapeutic effects, but the adulteration of honey in terms of botanical origin has increased, too. The floral origin of honeys is usually determined using melisso-palynological analysis and organoleptic characteristics, but the application of these techniques requires some expertise. A number of papers have confirmed the possibility of characterizing honey samples by selected chemical parameters. In this study high-resolution nuclear magnetic resonance (HR-NMR) and multivariate statistical analysis methods were used to identify and classify honeys of five different floral sources. The 71 honey samples (robinia, chestnut, citrus, eucalyptus, polyfloral) were analyzed by HR-NMR using both 1H NMR and heteronuclear multiple bond correlation spectroscopy (HMBC). Spectral data were analyzed by application of unsupervised and supervised pattern recognition and multivariate statistical techniques such as principal component analysis (PCA) and general discriminant analysis (GDA). The use of 1H-(13)C HMBC coupled with appropriate statistical analysis seems to be an efficient technique for the classification of honeys. 相似文献
136.
Wagner D Rousseau D Sidhom G Pouliot M Audet P Vieth R 《Journal of agricultural and food chemistry》2008,56(17):7964-7969
Considering the widespread insufficiency of vitamin D, the fortification of additional foods with vitamin D is warranted. The objective of this research was to assess the feasibility of vitamin D3 fortification in natural hard cheeses. We examined the recovery, distribution, long-term retention, and heat stability of the vitamin in industrially made fortified Cheddar and low-fat cheeses. The results indicated that the vitamin D3 did not degrade during processing, over 1 year of ripening (3-8 degrees C), or after thermal treatment at 232 degrees C for 5 min. Vitamin D3 recovery in the fortified Cheddar and low-fat cheeses were, respectively, 91 and 55% of the vitamin D3 added to the milk used to make each cheese. The remaining vitamin D3 was entrained in the whey. The vitamin D3 was uniformly distributed throughout the blocks of cheese. The fortification process did not alter the yield, chemical composition, or flavor of the Cheddar cheese. We conclude that industrially manufactured Cheddar and low-fat cheeses are suitable for vitamin D3 fortification. 相似文献
137.
Fragipan is a widely distributed subsoil horizon that induces severe limitations to plant growth and land use, mainly because of its high bulk density. In this work, we evaluated the pore‐size distribution through the analysis of the cumulative curve of intruded mercury volume in some soils with fragipan horizons. This approach provides information also about the arrangement of particles, thus we compared the results obtained for fragipan and nonfragipan horizons to relate porosity and particle arrangement with the specific physical properties of fragipans. The total volume of intruded mercury did not allow to discriminate between fragipan and nonfragipan horizons. However, from the variation of the pore volume as a function of the radius, two modal classes of pores were found, coarse and fine, respectively. The fine‐pore class arose from the arrangement of clay particles, and its volume was correlated to clay contents (r = 0.787) and to clay packing density (r = –0.621). The clay fractions in fragipans were less densely packed than in the other B horizons, even if they had similar clay contents. The coarser‐pore modal class is known to arise from the interactions between clay, silt, and sand particles, and its volume was different among horizons. Fragipan had a low volume of this modal pore class. In addition, a packing density for the coarser phase of 0.74, corresponding to a rhombohedral packing, was found only in fragipans. Thus, the low permeability and high bulk density of fragipans are linked to specific arrangements of the particles: an open packing of the clay phase is associated to an extremely dense packing of silt and sand. This combination is not present in any other soil horizon. 相似文献
138.
Brar GA Yassour M Friedman N Regev A Ingolia NT Weissman JS 《Science (New York, N.Y.)》2012,335(6068):552-557
139.
140.
Zarlenga DS Dawson H Kringel H Solano-Aguilar G Urban JF 《Veterinary immunology and immunopathology》2004,101(3-4):223-234