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21.
Tiamulin and a number of macrolides were evaluated as to their ability in forming metabolic-intermediate (MI) complexes with cytochrome P450 in liver microsomes from rabbits bred for meat production. Complex formation, which occurred only in preparations where the expression of P450 3A was increased as the result of rifampicin pre-treatment and with different kinetics, was in the order tiamulin > erythromycin > TAO approximately roxithromycin approximately tylosin and did not take place with tilmicosin and spiramycin. Most of the tested compounds underwent an oxidative N-dealkylation and a good relationship could be found between the rate of N-dealkylase activity in induced preparations and the aptitude in generating MI complexes. Although the results from in vitro studies should be interpreted with caution, it is suggested that the potential for in vivo drug interactions also exists in the rabbit for tiamulin and for four out of the six tested macrolides.  相似文献   
22.
Jaguars and pumas are threatened species in Brazil’s Atlantic Forest, especially at the borders of protected areas. This article assessed the influence of emotions, attitudes, existence value, and agency credibility on acceptability of big cats among rural residents living adjacent to two protected areas in this forest. Data from self-administrated questionnaires (= 326) indicated those with positive attitudes toward big cats (β = .28, < .001), those who valued the existence of big cats (β = .14, < .05), those who would feel sorrow if big cats disappeared (β = .21, < .001), and those who considered the managing agency as credible (β = .16, = .002) were more accepting of big cats. The model provided theoretical and practical insights into large carnivore conservation. For example, given the significance of agency credibility, a positive relationship between park authorities and residents is crucial for big cat conservation.  相似文献   
23.
European Journal of Plant Pathology - Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (FOL) is one of the main diseases affecting tomato plants. Three races (races 1, 2 and 3) of the...  相似文献   
24.
The aim of the present study was to determine whether arbuscular mycorrhizal (AM) inoculation with a biofertilizer containing clays as granular carriers, leek root pieces and Glomus intraradices spores could improve alkalinity tolerance of two cucumber genotypes, and to study the changes induced by AM at agronomical and physiological level. A greenhouse experiment was carried out to determine yield, growth, fruit quality, net photosynthesis (ACO2), electrolyte leakage, and mineral composition of two cucumber (Cucumis sativus L.) genotypes (hybrid “Ekron” or open-pollinated variety “Marketmore”) with inoculated and noninoculated arbuscular mycorrhizal biofertilizer. Plants were supplied with nutrient solutions at two pH values (6.0 or 8.1). The high pH nutrient solution had the same basic composition with an additional 10 mM NaHCO3 and 0.5 g l−1 CaCO3. The percentage root colonization was higher in “Marketmore” (21.8%) than “Ekron” (12.7%). Total and marketable yield and total biomass were significantly higher by 189%, 213%, and 77%, respectively, with Ekron in comparison to those recorded with Marketmore. The highest crop performance with Ekron in comparison to Marketmore was due to the improved nutritional status (higher N, P, K, Ca, Mg, Fe, Mn, and B), higher leaf area, and net photosynthesis. Increasing the concentration of NaHCO3 from 0 to 10 mM in the nutrient solution significantly decreased yield, plant growth, ACO2, N, P, Fe, Cu, Zn, Mn, and B concentration in leaf tissue, whereas the electrolyte leakage increased. The inoculated plants under alkaline conditions had higher total, marketable yield, and total biomass than noninoculated plant. Mycorrhizal cucumber plants grown under alkaline conditions had a higher macronutrient concentration in leaf tissue compared to noninoculated plants. The highest yield and biomass production in inoculated plants seems to be related to the capacity of maintaining higher net ACO2 and to a better nutritional status (high P, K, Mg, Fe, Zn, and Mn and low Na accumulation) in response to bicarbonate stress with respect to −AM plants.  相似文献   
25.
26.
Absorption of dietary anthocyanins is limited; however, fecal anthocyanin excretion has been rarely studied. We developed a method for extraction and analysis of fecal anthocyanins. Aqueous methanol (60%) maximized extraction efficiency (approximately 88%). Severe anthocyanin degradation (monitored by high-performance liquid chromatography) was observed in feces stored at -18 degrees C; therefore, storage time should be minimized and lower temperatures used. Fecal and cecal content samples were collected from 32 rats receiving either chokeberry, bilberry, grape-enriched (3.85 g monomeric anthocyanin per kg diet), or control diet for 14 weeks. Fecal anthocyanin concentrations were significantly different among groups (0.7/1.8/2.0 g/kg wet feces, chokeberry/bilberry/grape). Anthocyanin profiles of cecal contents and feces were similar. Losses in the intestinal contents were high for anthocyanin glucosides, moderate for galactosides, and negligible for arabinosides or xylosides. Acylation or diglucosylation enhanced anthocyanin stability. High anthocyanin concentration in the fecal content may favor anthocyanin absorption into the colon epithelial cells, resulting in potential health benefits.  相似文献   
27.
The reliability and efficiency of pressurized fluid extraction (PFE) technique for the extraction of total lipid content from cod and the effect of sample treatment on the extraction efficiency have been evaluated. The results were compared with two liquid-liquid extraction methods, traditional and modified methods according to Jensen. Optimum conditions were found to be with 2-propanol/n-hexane (65:35, v/v) as a first and n-hexane/diethyl ether (90:10, v/v) as a second solvent, 115 degrees C, and 10 min of static time. PFE extracts were cleaned up using the same procedure as in the methods according to Jensen. When total lipid yields obtained from homogenized cod muscle using PFE were compared yields obtained with original and modified Jensen methods, PFE gave significantly higher yields, approximately 10% higher (t test, P < 0.05). Infrared and NMR spectroscopy suggested that the additional material that inflates the gravimetric results is rather homogeneous and is primarily consists of phospholipid with headgroups of inositidic and/or glycosidic nature. The comparative study demonstrated that PFE is an alternative suitable technique to extract total lipid content from homogenized cod (lean fish) and herring (fat fish) muscle showing a precision comparable to that obtained with the traditional and modified Jensen methods. Despite the necessary cleanup step, PFE showed important advantages in the solvent consumption was cut by approximately 50% and automated extraction was possible.  相似文献   
28.
Tomato and transgenic oilseed rape plants expressing the Cf-9 resistance gene develop a hypersensitive response (HR) after injection of the corresponding Avr9 gene product. It was investigated whether induction of a HR conferred resistance to different fungal pathogens in tomato and oilseed rape. Induction of an AVR9 mediated HR at the pathogen infection site delayed the development of the biotrophs Oidium lycopersicum in tomato and Erysiphe polygoni in oilseed rape, but enhanced the development of the necrotrophs Botrytis cinerea and Alternaria solani in tomato and Sclerotinia sclerotiorum in oilseed rape. Interestingly, delayed fungal disease development was observed in plant tissues surrounding the HR lesion regardless of whether a necrotrophic or biotrophic pathogen was used. In tomato, AVR9 injection induced systemic expression of PR1, PR2 and PR3 defence genes but did not induce systemic resistance to O. lycopersicum, B. cinerea or A. solani. In oilseed rape, AVR9 injection temporarily induced systemic resistance to Leptosphaeria maculans and E. polygoni, but did not induce detectable systemic expression of PR1, PR2 or Cxc750. These results give new insights into the potential uses of an induced HR to engineer disease resistance.  相似文献   
29.
  1. Detailed knowledge about the distribution of species in need of protection is required for the management of Marine Protected Areas, a major tool to reduce marine biodiversity loss. Such knowledge is deficient for most marine invertebrates.
  2. Axinella polypoides is a marine sponge included on the list of protected species by the Barcelona Convention (1976) and the Bern Convention (1987). This large and erect species has an important ecological role in habitat forming and benthic–pelagic coupling.
  3. Bathymetrical, geographical and ecological data over the last 60 years were collated from publications and reports, together with new surveys to assess the distribution and protection status in Liguria of A. polypoides. It identified a more widespread distribution than previously thought, which points at a general need for dedicated investigations on the occurrence of species that require protection.
  4. Bathymetrical distribution was trimodal, with peaks corresponding to different geomorphological settings: coastal cliff bases (around 38 m depth), inner shelf shoals (52 m) and rocks amidst coarse sediment on the outer shelf (79 m). Density was significantly greater at the shallowest depths. The species was mostly found in the coralligenous biocoenosis, in association with other characteristic species or forming a monospecific facies.
  5. On (sub)vertical cliffs, A. polypoides often exhibited an unusual cane shape, rather than the typical bushy morphology, thus causing confusion with the congeneric A. cannabina, a more southern species. Records of the latter in the Ligurian Sea therefore need confirmation.
  6. Only a minority (22.6%) of A. polypoides records were in Marine Protected Areas, the remainder being located in areas with no current environmental protection plans in place. While the occurrence of this species in MPAs remained stable over the decades, the only quantitative historical data available indicated that populations in non-protected areas were declining owing to anthropogenic impacts (fishing and anchoring).
  相似文献   
30.
The methanol and ethyl acetate extracts of the aerial parts of Cirsium tenoreanum, have been evaluated for their phytochemical constituents and antibacterial and cytotoxic properties. Three flavonoids, apigenin, quercetin-3-O-galactoside and kaempferol-3-O-ramnoside, were isolated. The ethyl acetate extract showed a good antiproliferative activity.  相似文献   
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