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31.
Summary

To evaluate germplasm variability and to identify DNA profiles useful for tracing the genetic identity of olive oil, we used six Simple Sequence Repeats (SSRs) in 47 cultivated olive varieties from Central and Southern Italy. A total of 80 polymorphic SSR markers were scored and both the observed heterozygosity and the polymorphic index content were, on average, high. Genetic similarities were investigated by agglomerative hierarchical clustering and principal component analysis. The results implied that most of the olive accessions from the Campania region were genetically different from those of other Italian regions. This finding was further supported by partitioning the genetic variability using analysis of molecular variance. Furthermore, we analysed the DNA isolated from the fruit and mono-varietal oils of three cultivars. Comparative analysis of the SSR profiles revealed that these were conserved in the agro-food chain, although our data also suggested that some issues, such as the sensitivity and performance of the assay in complex mixtures, may pose limitations. Our findings extend current knowledge of Italian olive germplasm and highlight the richness and specificity of the genetic resource of olives in some regions of Southern Italy. They also provide molecular information that can be exploited for the protection of genetic material and mono-varietal oils.  相似文献   
32.
European sea bass, Dicentrarchus labrax, is one of the main species cultured in Europe. In this study, non-invasive techniques such as visible-near infrared spectroscopy and dynamometric analysis were used to discriminate concrete tank–cultured sea bass from sea cage–cultured sea bass. A total of 198 samples were collected at six time points from 3 Italian fish farms. A partial least squares analysis was conducted on individual animals at 48 and 96 h post-mortem to determine whether textural and spectral parameters can discriminate between concrete tank– and sea cage–reared sea bass. The results of this analysis demonstrated that spectral measurements better discriminate individual animals at 48 h post-mortem (87% in the independent test) with respect to 96 h post-mortem (66.7% in the independent test). Differences in texture were observed between the two groups of fish, but the texture changed in the time. The texture in sea cage–cultured fish showed higher values of measured force (N) with respect to fish reared in concrete tanks at 48 h post-mortem. Instead, opposite results were observed at 96 h post-mortem. Fillet colour were influenced by both farm and rearing condition.  相似文献   
33.
The Ultisols in the Raña de Cañamero area in Southwest Spain showed aluminum (Al) phytotoxicity, and the clearance of natural vegetation and decades of intensive conventional agriculture caused the deplation of soil organic matter (SOM). Therefore, we studied the long-term effects of no tillage and liming using sugar beet foam (SF) and red gypsum (RG), alone or in combination, on the restoration of Ultisols affected by acidification, Al phytotoxicity, and SOM depletion. We measured the main soil chemical properties, soil microbial biomass, soil enzyme activities involved in carbon, nitrogen, phosphorus, and sulfur mineralization, and the emission of volatile organic compounds (VOCs). The results indicated that liming effectively neutralized the soil acidity in the long term and, in combination with no tillage, significantly increased soil microbial biomass and enzyme activities. Twenty-three VOCs were detected using the proton transfer reaction-time of flight (PTR-ToF) technique, and both liming and tillage changed the VOC emission patterns. The greatest difference in VOC emission pattern was observed between no-tilled un-amended soils and tilled lime-amended soils, suggesting the activation of different metabolic pathways within the microbial communities of soils under different management. Differences in VOC emission patterns could be attributed to the decomposition of carbohydrates, which were also sustained by the higher enzyme activities in the lime-amended soils.  相似文献   
34.
Morphological changes in Senegalese sole adults (Solea senegalensis Kaup, 1858) reared at two stocking density conditions (low stocking density, 60% of bottom occupation and high stocking density, 180% of bottom occupation) were investigated using geometric morphometrics. Canonical variate analysis on weight matrix scores, including the uniform component (W′), at the end of the experiment revealed differences in body shape between experimental groups. The low density group presented a similar change pattern as that of the high density group but was less intense. Differences were discussed in terms of the effect of a high stocking density on the shape of soles which were very close to commercialization. Results did not indicate a significant size-related shape, likely due to fish age. Our results provide the first promising look at environment-related shape changes in reared sole.  相似文献   
35.
Plitidepsin is a cyclic depsipeptide of marine origin in clinical development in cancer patients. Previously, some depsipeptides have been linked to increased cardiac toxicity. Clinical databases were searched for cardiac adverse events (CAEs) that occurred in clinical trials with the single-agent plitidepsin. Demographic, clinical and pharmacological variables were explored by univariate and multivariate logistic regression analysis. Forty-six of 578 treated patients (8.0%) had at least one CAE (11 patients (1.9%) with plitidepsin-related CAEs), none with fatal outcome as a direct consequence. The more frequent CAEs were rhythm abnormalities (n = 31; 5.4%), mostly atrial fibrillation/flutter (n = 15; 2.6%). Of note, life-threatening ventricular arrhythmias did not occur. Myocardial injury events (n = 17; 3.0%) included possible ischemic-related and non-ischemic events. Other events (miscellaneous, n = 6; 1.0%) were not related to plitidepsin. Significant associations were found with prostate or pancreas cancer primary diagnosis (p = 0.0017), known baseline cardiac risk factors (p = 0.0072), myalgia present at baseline (p = 0.0140), hemoglobin levels lower than 10 g/dL (p = 0.0208) and grade ≥2 hypokalemia (p = 0.0095). Treatment-related variables (plitidepsin dose, number of cycles, schedule and/or total cumulative dose) were not associated. Electrocardiograms performed before and after plitidepsin administration (n = 136) detected no relevant effect on QTc interval. None of the pharmacokinetic parameters analyzed had a significant impact on the probability of developing a CAE. In conclusion, the most frequent CAE type was atrial fibrillation/atrial flutter, although its frequency was not different to that reported in the age-matched healthy population, while other CAEs types were rare. No dose-cumulative pattern was observed, and no treatment-related variables were associated with CAEs. Relevant risk factors identified were related to the patient's condition and/or to disease-related characteristics rather than to drug exposure. Therefore, the current analysis supports a safe cardiac risk profile for single-agent plitidepsin in cancer patients.  相似文献   
36.
37.
Psychologists and economists have long appreciated the contribution of reward history and expectation to decision-making. Yet we know little about how specific histories of choice and reward lead to an internal representation of the "value" of possible actions. We approached this problem through an integrated application of behavioral, computational, and physiological techniques. Monkeys were placed in a dynamic foraging environment in which they had to track the changing values of alternative choices through time. In this context, the monkeys' foraging behavior provided a window into their subjective valuation. We found that a simple model based on reward history can duplicate this behavior and that neurons in the parietal cortex represent the relative value of competing actions predicted by this model.  相似文献   
38.
The aim of this study was to evaluate the effects of experimental amendments on yields of Trifolium subterraneum L., Pisum arvense L., and Lolium multiflorum Lam., and on soil characteristics. A two-year research was carried out comparing anaerobic digestate (AD) and olive-pomace compost (OPC) with mineral fertilizer (Min), commercial organic-mineral fertilizer (Org-min), and unfertilized control (Cont). Anaerobic digestate and OPC were firstly analyzed for their chemical characteristics. The most important parameters were recorded and soil properties were investigated. Anaerobic digestate showed the highest dry weight for ryegrass, the best yield in pea, and good level of dry matter in clover. Good responses were achieved by OPC. Anaerobic digestate increased total soil organic carbon by 14.4, 8.1 and 7.6% than Min, Org-min and Cont, respectively. Olive-pomace compost increased the same parameter by 16.3, 10.0, and 9.5%. The findings indicated the possibility to substitute mineral fertilizers with organic ones without decreasing yields and support soil fertility.  相似文献   
39.
The detection of genetically modified organisms (GMOs) in food and feed is an important issue for all the subjects involved in raw material control, food industry, and distribution. Because the number of GMOs authorized in the EU increased during the past few years, there is a need for methods that allow a rapid screening of products. In this paper, we propose a method for the simultaneous detection of four transgenic maize (MON810, Bt11, Bt 176, and GA21) and one transgenic soybean (Roundup Ready), which allows routine control analyses to be sped up. DNA was extracted either from maize and soybean seeds and leaves or reference materials, and the recombinant DNA target sequences were detected with 7 primer pairs, accurately designed to be highly specific for each investigated transgene. Cross and negative controls were performed to ensure the specificity of each primer pair. The method was validated on an interlaboratory ring test and good analytical parameters were obtained (LOD = 0.25%, Repeatability, (r) = 1; Reproducibility, (R) = 0.9). The method was then applied to a model biscuit made of transgenic materials baked for the purpose and to real samples such as feed and foodstuffs. On account of the high recognition specificity and the good detection limits, this multiplex PCR represents a fast and reliable screening method directly applicable in all the laboratories involved in raw material and food control.  相似文献   
40.
Lipid transfer proteins (LTPs) are a family of low molecular mass (7-9 kDa) polypeptides, the members of which share 35-95% sequence homology. These proteins are widely distributed throughout the plant kingdom and are receiving attention for their biochemical characteristics and biological activity. LTPs are indeed studied in different research fields varying from allergy to food technology, and numerous molecules belonging to this class are progressively being identified and investigated. Proteins from pomegranate juice were fractioned by cation exchange chromatography and analyzed by SDS-PAGE. Two proteins were identified as putative LTPs on the basis of their molecular weights and their electrophoretic behaviors under reducing and nonreducing conditions. Finally, proteins were purified and characterized by mass spectrometry. This analysis confirmed that the two polypeptides are LTPs on the basis of an amino acid sequence common to LTPs from other plant sources and cysteine content. The two proteins, named LTP1a and LTP1b, showed similar molecular masses but different immunological profiles when immunodetected with rabbit antibodies specific for Pru p 3 and human IgE from a patient suffering from pomegranate allergy. The demonstration of the existence of two immunologically unrelated LTPs in pomegranate confirms the variability and the complexity of the plant LTP family. This should be taken into account when the role of these proteins as elicitors of allergies to fruits is investigated and could help to explain the contradictory literature data on pomegranate allergy.  相似文献   
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