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51.
Caboni P Sarais G Angioni A Garcia AJ Lai F Dedola F Cabras P 《Journal of agricultural and food chemistry》2006,54(26):10026-10032
Azadirachtoids were determined by liquid chromatography/mass spectrometry (LC/MS) in five methanolic seed extracts of the neem tree and in a commercial formulation. On average, seed extracts contain azadirachtin A (10.9%), azadirachtin B (3.5%), nimbin (10.4%), and large quantities of salannin (19.0%). The composition of the commercial formulations may present different azadirachtoids contents depending on the natural extracts used in the preparation. Because these compounds may also show insecticide activity, the efficacy on field of these formulations may be very different. Photodegradation of pure azadirachtoids was also studied. Azadirachtins and related compounds are very sensitive to sunlight, degrading rapidly, with half-lives of the order of 11.3 h for azadirachtin A and 5.5 h for azadirachtin B and few minutes for the other limonoids compounds studied. The residues of azadirachtins and the main constituents, e.g., salannin, nimbin, deacetylnimbin, and deacetylsalannin, of the neem seed extract were determined on strawberries after field treatment using two different formulations. This residue study on strawberry was carried out to assess not only the azadirachtin content but also the main azadirachtoids contents. Three days after field application at five times the dose recommended by the manufacturer, residues of azadirachtin A and B were 0.03 and 0.01 mg/kg, respectively, while residues of salannin (LOQ 0.01 mg/kg) and nimbin (LOQ 0.5 mg/kg) were not detectable. 相似文献
52.
Caboni P Sarais G Angioni A Garau VL Cabras P 《Journal of agricultural and food chemistry》2005,53(22):8644-8649
A simple multiresidue method for screening analysis of 12 botanical insecticides used by organic farmers has been developed. The method involves a rapid and small-scale extraction procedure with acetonitrile. For all fruit and vegetable samples, there was no need for clean up. Rotenone, azadirachtin, ryanodines, and pyrethrins can be separated by high-performance liquid chromatography, quantified, and confirmed with a diode array detector (DAD) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) in the select ion-monitoring mode (SIM). The majority of pesticide recoveries for various fruits and vegetables were >70% in the concentration range from 0.01 to 5 mg/kg. The limit of quantitation for most of the pesticides was 0.01 mg/kg, with the majority of relative standard deviations (RSD) mostly below 10%. 相似文献
53.
Angioni A Dedola F Minelli EV Barra A Cabras P Caboni P 《Journal of agricultural and food chemistry》2005,53(10):4059-4063
The behavior of pyrethrins and piperonyl butoxide (PB) on peaches has been studied after field treatment. Three experiments were carried out at 1, 5, and 10x the concentration recommended by the manufacturer. In all experiments, the initial deposition was below the maximum residue level (MRL), and the half-life time calculated in the 10x experiment for total pyrethrins within 2.3 days was in agreement with the preharvest interval (PHI) recommended. In a model system, the photodegradation rates of the pyrethrins in three commercial products were compared with pyrethrum pale (PP), with and without the presence of peach waxes. The pyrethrins in formulations containing PB showed higher half-life times but were not influenced by the presence of waxes, whereas in the case of PP that does not contain any PB, photodegradation was significantly affected by the presence of waxes. 相似文献
54.
Bucelli P Costantini EA Barbetti R Franchini E 《Journal of agricultural and food chemistry》2011,59(15):8304-8313
This research considered the varieties 'Frantoio' and 'Moraiolo' growing in rainfed olive trees (Olea europaea) and took place in Tuscany, central Italy. Soil moisture was monitored during the very meteorologically contrasting years 2002 and 2003 in two nearby olive groves. The plots had the same morphological and climatic conditions, but different soil types. Monocultivar oil samples were analyzed to determine fatty acids, minor polar compounds, and tocopherols content and were submitted to organoleptic analysis by a panel of trained tasters. The results highlighted that soil water regimen affects some nutraceutical components and the sensory evaluation of olive oil. Cultivar also affected yield components, polyphenols, and tocopherols content, but less than soil water availability. The plants on the soil inducing a relatively more intense and longer water deficit during summer (a Skeleti Calcaric Regosol) had an early ripening and gave the best results in terms of phenolic compounds and, consequently, antioxidant properties of the olive oil. The sensorial properties of the oil obtained from both cultivars on the Regosol were superior in both years of the trial. 相似文献
55.
Samples from feline normal, dysplastic, and neoplastic mammary tissues were used to investigate the usefulness of MIB-1 labeling index (MIB-1 I) as a prognostic indicator. Forty-eight queens bearing invasive carcinomas were included in a 2-year follow-up study. Mammary lesions were classified according to the World Health Organization system, and invasive carcinomas were further graded on the basis of the degree of tubule formation, the degree of nuclear and cellular pleomorphism, and mitotic count. Additional sections were immunostained using MIB-1 antibody, and MIB-1 I was expressed as a percentage of positive nuclei. In normal mammary gland tissues, the mean MIB-1 I was <1%. A low proliferation rate was found in all mammary adenosis and in situ carcinomas, and the highest rates were observed in feline mammary hypertrophy and invasive carcinomas. Twenty-one (43.7%) of the queens bearing invasive carcinomas were still alive at the end of the trial, and 27 (56.2%) had died. The MIB-1 I was not significantly correlated with clinical outcome, age, histologic type, or grading of the tumors, but a borderline correlation was observed with invasion of lymphatic vessels. Univariate analysis showed that high MIB-1 I was also not associated with decreased overall survival, whereas the grading system of the tumors had high predictive value (P = 0.0040) for postsurgery survival. The lack of correlation between MIB-1 I and postsurgery survival suggests that this marker alone is not sufficient to determine a correct prognosis in feline mammary carcinomas, even if it is a useful proliferation marker. 相似文献
56.
Canine haemangiopericytoma (CHP) is a vascular neoplasm thought to be derived from pericytes. The histological pattern and immunohistochemical profile were studied in 31 CHPs. Twenty-three subjects were followed for 2 years to evaluate the correlation among tumour location, histotype, immunostaining and outcome of the disease. Of the 31 CHPs examined, 20 exhibited a perivascular whorled pattern, 8 were storiform and 3 were epithelioid. All tumours were positive for vimentin and negative for cytokeratin, factor VIII-related antigen, glial fibrillary acidic protein and S-100 protein. Seventeen CHPs were positive for actin and nine co-expressed desmin. Six CHPs were also positive for CD34 antigen. The panel of immunohistochemical markers used confirmed the vascular lineage of CHP and aided in the exclusion of other mesenchymal tumours. Of the 23 dogs submitted to follow-up, 6 had recurrence or metastases of the primary tumour. The epithelioid pattern or a noncutaneous location were associated with a poorer prognosis. 相似文献
57.
Muscle activity as a key indicator of welfare in farmed European sea bass (Dicentrarchus labrax L. 1758) 下载免费PDF全文
Pierluigi Carbonara Maria Scolamacchia Maria Teresa Spedicato Walter Zupa Robert Scott McKinley Giuseppe Lembo 《Aquaculture Research》2015,46(9):2133-2146
Groups of adult sea bass were reared at either low (10 kg m?3) or high (50 kg m?3) stocking densities respectively for 84 and 116 days. To monitor the red muscle activity, about 20 fish from both densities were surgically implanted with EMG (Electromyograms) radio transmitters, after EMG calibration during exhaustive swimming exercise (Ucrit test). Blood samples and morphometric measurements were also taken. EMG showed that the muscle activity of fish reared at 50 kg m?3 was on average twofold higher than fish kept at lower density. Cortisol was significantly more elevated at higher density and haemoglobin, haematocrit and RBCC (red blood cells count) showed the same trend, while lysozyme decreased. Patterns for glucose and lactate were less clear. The results showed that the contemporary use of functional (EMG) and physiological (haematological and biochemical) profiles could give a more comprehensive view of the fish status validating the diagnosis of fish stress induced by culture practices. 相似文献
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59.
Pierluigi BOMBI 《干旱区科学》2018,10(5):663-672
Climate change is threatening natural ecosystems in the Earth, and arid regions of southern Africa are particularly exposed to further drying. Welwitschia mirabilis Hook.(Welwitschiaceae) is an unusual gymnosperm tree that is recognized as an icon of the Namib Desert, southern Africa. Many aspects of its biology were investigated in the past, with a special emphasis for its physiology and adaptations, but nothing is known about its potential sensitivity to current climate changes. In this study, we adopted an approach based on distribution data for W. mirabilis and ecological niche models for clarifying the species-climate interactions and for predicting the potential impacts of climate change on W. mirabilis populations in three well-separated sub-ranges(northern, southern and central) in northwestern Namibia, southern Africa. We evidenced that the populations occurring in the northern sub-range have peculiar climatic exigencies compared with those in the central and southern sub-ranges and are particularly exposed to the impact of climate change, which will consist of a substantial increase in temperature across the region. These impacts could be represented by demographic changes that should be detected and monitored detailedly to plan efficient measures for managing populations of this important species on the long-term scale. 相似文献
60.
Paolo Sartor Pierluigi Carbonara Sandro Cerasi Giuseppe Lembo Maria Teresa Facchini Alessandro Lucchetti Rosaria Felicita Sabatella Claudia Musumeci Walter Zupa Maria Teresa Spedicato 《Fisheries Management and Ecology》2019,26(6):661-673
Small‐scale driftnets (SSDs) have been historically used in the Mediterranean without major environmental concern. The introduction of large‐scale driftnets caused unwanted catches of protected species. Specific regulations were therefore issued in European waters, culminating in a proposed moratorium on SSDs. This study aimed to characterise the SSD fishery targeting anchovy (menaide), evaluating its environmental sustainability, economic performance and social relevance. In 2013, a survey by interviews, logbooks and observers on board assessed the order of magnitude of this fishery in terms of fishing capacity and activity, volume of landings and revenues. The menaide fleet consisted in 60 vessels <12 m overall length, moored in little harbours in southern Italy. These nets are highly selective: the target species, European anchovy, Engraulis encrasicholus (L.) and sardine, Sardina pilchardus (Walbaum), dominates the catches, while discards are negligible. The anchovies caught are of high quality and large size; the high prices support fish processing by local factories. Moreover, the results of a SWOT analysis demonstrated that replacing SSDs with a semi‐industrial fishery, like purse seining, would increase impacts on the ecosystem, and a loss of socio‐economic opportunities for several coastal villages. These findings support the option of keeping SSDs operating, in the framework of specifically oriented management measures. 相似文献