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41.
The increasing demand for traditional and natural foods has renewed the interest in hulled wheat species. Among these, Triticum dicoccum Schübler has survived in Italy only in a few hilly and mountainous areas of central and southern Italy. As a rule, emmer is cultivated in marginal areas with organic farming procedures that use very low N inputs, since this wild species is characterised by low yield, long and weak culms that easily lodge under windy conditions. Unfortunately, there is a lack of information on crop productivity and N effect for this crop. Research was carried out to study the effect of cultivation year (2004 and 2005), plant origin (Garfagnana, Leonessa and Molise) and N dressing (N0, N30, N60 and N90 kg ha−1) on crop yield and grain quality of emmer grown in south-central Italy. Fertilizer was split at seeding, tillering and stem elongation. Tested parameters were highly influenced either by crop origin or N application (biomass, hulled and threshed grain yield, spikes m−2, spikelets per spike, kernel weight, plant height, lodging, kernel ash and proteins). Several parameters augmented as fertilization rate increased (hulled and unhulled grain yield, biomass accumulation, spikes m−2, kernels m−2, protein content); 1000-kernel weight showed an opposite trend and in some cases no differences were noticed among fertilized treatments (plant height and spikelets per spike). Molise was the most productive population, closely followed by Garfagnana. The present research rejected some common belief that emmer has to be grown without N dressing, and crop undergoes lodging in marginal mountainous areas. Besides, grain yield of N90 and N60 treated emmer was only 6 and 18% lower compared to the five most important durum wheat varieties cultivated in the same area, suggesting emmer as a possible alternative crop to durum wheat in marginal areas of Mediterranean-type agro-ecosystems. 相似文献
42.
Antonia Concetta Elia Valentina Ciccotelli Nicole Pacini Ambrosius Josef Martin Dörr Marilena Gili Mauro Natali Laura Gasco Marino Prearo Maria Cesarina Abete 《Fish physiology and biochemistry》2014,40(4):1055-1068
Oxytetracycline (OTC) is employed in fish farms to contest or prevent bacterial infections. We simulated an OTC treatment at therapeutic level (75 mg kg?1) and at higher doses (150, 300 mg kg?1) for 10 days. A withdrawal period of 10 days was considered for treated carp, carrying out the same chemical and biochemical analyses (total glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase and malondialdehyde). The aim was to obtain data related to the carryover in muscle and on variations in the antioxidant indicators in liver and kidney. The OTC residual levels in muscle showed a dose–response relationship. After 10 days of treatment at the recommended dose (75 mg kg?1), the mean value in muscle was 295 μg kg?1. After 10 withdrawal days, residues in all treated groups were not entirely eliminated by fish. Residues of recommended 75 mg kg?1 OTC dose were lower than the maximum permitted by EEC regulation: 100 μg kg?1. Disturbance in the antioxidant systems in liver and kidney was recorded in (150, 300 mg kg?1) carp, as well as during the withdrawal period. A lowered superoxide dismutase activity and higher levels of catalase, glutathione peroxidase, glutathione reductase and glutathione were evaluated in liver, while in kidney only higher malondialdehyde and glutathione S-transferase concentrations were recorded for 300 mg kg?1 dose. The therapeutic OTC dose exerted lower effects, and only in liver, enhancement of GPx and GR activities was recorded. After the withdrawal period, altered antioxidant responses in tissues were restored for all three OTC doses. 相似文献
43.
Marino Garcia-Montijano J. Julio de Lucas María Dolores de San Andrés 《Research in veterinary science》2011,90(2):288-290
The pharmacokinetics properties of marbofloxacin were studied in adult Eurassian Griffon vulture after single-dose intravenous (IV) administration of 2 mg/kg. Drug concentration in plasma was determined by high-performance liquid chromatography and the data obtained were subjected to compartmental and non-compartmental kinetic analysis. Marbofloxacin presented a volume of distribution at steady-state (Vdss) of 1.51 ± 0.22 L and total plasma clearance (Cl) of 0.109 ± 0.023 L/h kg. The permanence of this drug was long in vultures (T1/2λ = 12.51 ± 2.52 h; MRT∞ = 13.54 ± 2.29 h). The optimal dose of marbofloxacin estimated is 2.73 mg/kg per day for the treatment of infections in vultures with MIC90 = 0.2 μg/mL. 相似文献
44.
In this study, an experimental challenge was carried out by feeding Nero Siciliano pigs with acorn to evoke melanin-like pigmentation and support the hypothesis that it is caused by ingested material. Twelve pigs were studied, 6 fed with acorns and 6 fed commercial feed. At slaughter, all the animals fed on acorns showed black discolouration of almost all lymph nodes. The lymph nodes were normal in size and shape. Histochemical tests performed on tissues allowed us to identify and differentiate the pigment. Immunohistochemical staining for macrophage markers showed macrophages containing a variable amount of melanin-like granules. Our data, and the well-known steps of melanin formation, confirm that swine enzymes could act on phenolic substances found in acorns. 相似文献
45.
Macrì F Marino F Rapisarda G Lanteri G Mazzullo G 《Anatomia, histologia, embryologia》2011,40(2):104-106
A case of unilateral hindlimb adactyly is described in a 3-month-old female Pointer dog. Clinical and radiographic findings are described. Adactyly or transverse hemimelia is a rare condition in most animal species. In dogs, this condition has been reported only three times as a deformity of the forelimb. To the authors' knowledge, the congenital pelvic limb deformity described here is the first case documented in a dog. 相似文献
46.
Transnasal administration of a combination of dexmedetomidine,midazolam and butorphanol produces deep sedation in New Zealand White rabbits 下载免费PDF全文
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Interaction of four monoterpenes contained in essential oils with model membranes: implications for their antibacterial activity 总被引:1,自引:0,他引:1
Cristani M D'Arrigo M Mandalari G Castelli F Sarpietro MG Micieli D Venuti V Bisignano G Saija A Trombetta D 《Journal of agricultural and food chemistry》2007,55(15):6300-6308
The present article reports the antimicrobial efficacy of four monoterpenes (thymol, carvacrol, p-cymene, and gamma-terpinene) against the Gram-positive bacterium Staphylococcus aureus and the Gram-negative bacterium Escherichia coli. For a better understanding of their mechanism of action, the damage caused by these four monoterpenes on biomembranes was evaluated by monitoring the release, following exposure to the compounds under study, of the water-soluble fluorescent marker carboxyfluorescein (CF) from large unilamellar vesicles (LUVs) with different lipidic composition (phosphatidylcholine, PC, phosphatidylcholine/phosphatidylserine, PC/PS, 9:1; phosphatidylcholine/stearylamine, PC/SA, 9:1). Furthermore, the interaction of these terpenes with dimyristoylphosphatidylcholine multilamellar vesicles as model membranes was monitored by means of differential scanning calorimetry (DSC) technique. Finally, the results were related also with the relative lipophilicity and water solubility of the compounds examined. We observed that thymol is considerably more toxic against S. aureus than the other three terpenes, while carvacrol and p-cymene are the most inhibitory against E. coli. Thymol and carvacrol, but not gamma-terpinene and p-cymene, caused a concentration-dependent CF leakage from all kinds of LUVs employed; in particular, thymol was more effective on PC and PC/SA LUVS than on PC/PS vesicles, while carvacrol challenge evoked a CF leakage from PC/PS LUVs similar to that induced from PC/SA LUVs, and lower than that measured with PC vesicles. Concerning DSC experiments, these four terpenes caused a decrease in Tm and (especially carvacrol and p-cymene) DeltaH values, very likely acting as substitutional impurities. Taken together, our findings lead us to speculate that the antimicrobial effect of thymol, carvacrol, p-cymene, and gamma-terpinene may result, partially at least, from a gross perturbation of the lipidic fraction of the plasmic membrane of the microorganism. In addition to being related to the physicochemical characteristics of the compounds (such as lipophilicity and water solubility), this effect seems to be dependent on the lipidic composition and net surface charge of the microbic membranes. Furthermore, the compounds might cross the cell membranes, thus penetrating into the interior of the cell and interacting with intracellular sites critical for antibacterial activity. 相似文献
50.
Sarpietro MG Spatafora C Tringali C Micieli D Castelli F 《Journal of agricultural and food chemistry》2007,55(9):3720-3728
The interaction of resveratrol (trans-3,5,4'-trihydroxystilbene) and two of its derivatives (3,5,4'-tri-O-methylresveratrol and 3,5,4'-tri-O-triacetylresveratrol) with biomembrane models, represented by dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles (MLV), has been studied by differential scanning calorimetry (DSC). The analysis of MLV prepared in the presence of increasing molar fraction of such compounds has been carried out to reveal their maximum interaction with biomembrane models. The results from these studies have been compared with kinetic experiments results, in order to detect the entity and rate of compound absorption by the biomembrane models. The findings indicate that the compounds affected the thermotropic properties of DMPC MLV by suppressing the pretransition peak and broadening the DMPC main phase transition calorimetric peak and shifting it to lower temperatures. The order of effectiveness found was resveratrol > trimethylresveratrol > triacetylresveratrol. The kinetic experiments reveal that in an aqueous medium the absorption of resveratrol by the biomembranes models is allowed, whereas the absorption of its derivatives is hindered; in contrast when a lipophilic medium is employed, all three compounds are easily absorbed. 相似文献