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71.
Veterinary Research Communications - Research data on milk composition in cetaceans are scattered and fragmentary. This paper analyses the gross and mineral composition, the fatty acids profile and...  相似文献   
72.
The extracts of four rare plants found on the islands of Sicily, Vulcano and Marettimo, Southern Italy, were screened for their inhibitory effect on the production of leukotriene B4 by 5-lipoxygenase in intact cells. The methanol extracts of pods of Cytisus aeolicus and aerial parts of Thymus richardii were the most active extracts, inhibiting almost completely the leukotriene B4 production at 200 and 50 microg/ml, respectively.  相似文献   
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Satellite estimate of grass biomass in a mountainous range in central Italy   总被引:1,自引:0,他引:1  
One of the main problems in managing ranges used for extensive pastoralism is the difficulty of obtaining reliable estimates of grass biomass over very large areas. Estimates of grass biomass are useful as an indicator of both available forage and risk of soil erosion. Nevertheless, large scale field measurements are expensive and time-consuming. The use of satellite images may provide a complementary means of estimating grass biomass over very large areas at a reasonable cost. The aim of this study was to test the use of Landsat satellite data for estimating grass biomass in a mountainous range in central Italy used primarily for sheep breeding. During each of four ground campaigns carried out over two years, grass was cut and its biomass measured in 60-90 test plots. Four Landsat images taken simultaneously to the ground campaigns were processed to obtain several vegetation indexes calculated for each ground test plot. The vegetation indexes showed significant correlations with measured grass biomass. The Normalized Difference Vegetation Index (NDVI) provided the most accurate estimate of grass biomass. When data for each of the four ground campaigns were analyzed separately, correlations for early summer campaigns were higher than correlations for late summer campaigns, indicating that when the ratio of dry/green biomass increases, satellite estimate becomes less accurate. Overall, our results show that satellite data can provide a useful source of biomass information for the management of large ranges. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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Three-year-old seedlings of Pinus pinea L. were inoculated near the stem base with one of two Heterobasidion annosum (Fr.) Bref. sensu stricto (s.s.) strains belonging to two populations: the North American P-group (NAm-P) and the European P-group (Eur-P). The NAm-P strain caused smaller H. annosum stem lesions than the Eur-P strain. Three weeks after the stem inoculations with H. annosum, apical shoots were inoculated with Diplodia pinea (Desmaz.) J. Kick. Basal stem infection with H. annosum resulted in D. pinea causing longer necrotic lesions in the shoots, indicating systemic induced susceptibility (SIS) to this shoot blight pathogen. Furthermore, stem induction with the NAm-P strain resulted in higher susceptibility to D. pinea than stem induction with the Eur-P strain. Total terpene accumulation was suppressed by about 50% in the shoots under attack by D. pinea when seedlings were induced with H. annosum. Total terpene concentration in shoots inoculated with D. pinea was negatively correlated with lesion size, both overall and by stem treatment. Stem base inoculation with H. annosum induced whole-plant changes in ter-pe-noid profiles, but these were not associated with the SIS phenotype. We discuss our findings on modulation of systemic response of P. pinea to fungal attack in the context of tripartite ecological interactions.  相似文献   
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Toledo  R. M.  Perring  M. P.  Verheyen  K.  Martini  A. M. Z.  Ferreira  M. P.  Santos  R. F. 《Landscape Ecology》2020,35(6):1403-1416
Landscape Ecology - Neighbouring forests constitute biological sources that enable the succession from species-poor systems, such as tree-plantings, to highly diverse forests. However, old forest...  相似文献   
78.
The effects of ovine lentivirus infection on the fat, protein and lactose concentrations on the somatic cell counts in ewes' milk, on milk production and on the birth weight and growth of lambs were studied in a flock of Sardinian sheep from central Italy. Data on 61 lactations of ewes positive to both the agar-gel immunodiffusion test and an enzyme-linked immunosorbent assay were compared with those on 46 lactations of seronegative ewes. Confounders such as parity, age, lactation length, litter size, and the sex of the lambs were considered. None of these traits seemed to be negatively influenced by the infection  相似文献   
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