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In this study the characterization of white wines produced from the monovarietal 'Greco bianco' grape variety is presented for the first time. A total of 40 commercial wines, from two different southern Italian regions, Calabria and Campania, from the same grape variety and two different vintages, were investigated. The analyses were performed by means of chromatographic methods, conventional analyses, and nuclear magnetic resonance (NMR) spectroscopy. No differentiation was observed according to the year of production but a significant discrimination was achieved using principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). In particular, PLS-DA allowed the selection of compounds (total acidity; citric, malic, succinic, and lactic acids; total polyphenol index; glucose and proline/arginine ratio) useful for differentiating the studied wines on the basis of geographical origin.  相似文献   
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Cellulose and lignin degradation dynamics was monitored during the leaf litter decomposition of three typical species of the Mediterranean area, Cistus incanus L., Myrtus communis L. and Quercus ilex L., using the litter bag method. Total N and its distribution among lignin, cellulose and acid-detergent-soluble fractions were measured and related to the overall decay process. The litter organic substance of Cistus and Myrtus decomposed more rapidly than that of Quercus. The decay constants were 0.47 year−1, 0.75 year−1 and 0.30 year−1 for Cistus, Myrtus and Quercus, respectively. Lignin and cellulose contents were different as were their relative amounts (34 and 18%, 15 and 37%, 37 and 39% of the overall litter organic matter before exposure, for Cistus, Myrtus and Quercus, respectively). Lignin began to decrease after 6 and 8 months of exposure in Cistus and Myrtus, respectively, while it did not change significantly during the entire study period in Quercus. The holocellulose, in contrast, began to decompose in Cistus after 1 year, while in Quercus and Myrtus immediately. Nitrogen was strongly immobilized in all the litters in the early period of decay. Its release began after the first year in Cistus and Myrtus and after 2 years of decomposition in Quercus. These litters still contained about 60, 20 and 90% of the initial nitrogen at the end of the experiment (3 years). Prior to litter exposure nitrogen associated with the lignin fraction was 65, 54 and 37% in Cistus, Myrtus and Quercus, while that associated with the cellulose fraction was 30, 24 and 28%. Although most of the nitrogen was not lost from litters, its distribution among the litter components changed significantly during decomposition. In Cistus and Myrtus the nitrogen associated with lignin began to decrease just 4 months after exposure. In Quercus this process was slowed and after 3 years of decomposition 8% of the nitrogen remained associated with lignin or lignin-like substances. The nitrogen associated with cellulose or cellulose-like substances, in contrast, began to decrease from the beginning of cellulose decomposition in all three species. At the end of the study period most of the nitrogen was not associated to the lignocellulose fraction but to the acid-detergent-soluble substance (87, 88 and 84% of the remaining litter nitrogen).  相似文献   
25.
Phaseolin (PHAS) and phytohemagglutinin (PHA) represent the main seed protein fractions in common bean. Currently, several ecotypes of common bean cultivated in marginal areas exist, above all in Southern Italy regions. Such germplasm could be lost due to the genetic uniformity of new cultivars. Moreover, the first step to obtain community recognition and denomination requires the full characterization of the available germplasm. In the present study, PHAS and PHA extracted in saline solutions from nine ecotypes of common bean ‘di Controne’ (Campania region) were analysed by anionic and cation exchange-high performance liquid chromatography (AE- and CE-HPLC), SDS-PAGE and IEF. The results obtained by AE-HPLC have allowed us either to standardize a high resolution, cost-effective and time-saving biochemical methodology or to compare the studied ecotypes with some cultivars of common bean most widely grown in Italy. The elution profiles of the nine ecotypes, already analyzed at the morpho-physiological and molecular levels, allowed us to differentiate the ecotypes either from a qualitative point of view (presence/absence of one or more peaks) or a quantitative one. For instance, the ecotypes of common bean ‘di Controne’ could be clearly differentiated from some commercial cultivars of dwarf and/or climbing bean. In contrast, the analysis of the electrophoresis patterns supplied less information. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
26.
Water-, salt-, alcohol- and alkali-soluble seed storage proteins, extracted from 21 cipolla bianca di Pompei landraces (Allium cepa L.), were analyzed by anionic exchange-high performance liquid chromatography (AE-HPLC). Chromatographic elution profiles (time range 0–40 min) at 280 nm of water-soluble seed proteins evidenced the presence of 21 peaks, which allowed all the landraces studied to be distinguished from each other. The differences detected were both qualitative (presence/absence of one or more peaks) and quantitative; the water-soluble proteins were useful in differentiating landraces and cultivars while the other seed protein fractions only showed a weak polymorphism. The cluster analysis, based on HPLC data, showed that the landraces clustered with a genetic similarity degree ranging between 69% and 94%. The possibility of discriminating among closely related onion landraces during the course of breeding programmes could allow the identification of biochemical markers linked to useful agronomical traits. As observed by chromatographic analysis, the globulin composition of onion water-soluble seed protein appears to be independent of environmental growth conditions. The biochemical characterization of the available typical onion germplasm may contribute to obtain a community recognition and denomination, such as Denomination of Protected Origin (D.O.P.), Indication of Protected Origin (I.G.P.) or Specificity Attestation (A.S.). The biochemical method here developed resulted of high resolution, cost-effective and time-saving for characterization and genetic purity assessment of the landraces studied.  相似文献   
27.

Purpose

The increasing need for disposal of lake-dredged material (LDM) as a consequence of intensified natural and/or anthropogenically mediated erosion processes has lead the scientific community to find new strategies for its reuse. The aim of this study is to investigate the effect of LDM use on the biochemical and functional performance of a degraded soil affected by erosion and entisolization processes.

Materials and methods

As a paradigmatic case study, a hydrographic basin located in Sardinia (Italy) was investigated. Severe soil degradation processes affect this area and have resulted in intensive sheet and rill water erosion. In contrast, an increase in sedimentation has been recorded on the bottom of an artificial lake. A degraded soil, collected in this area, were treated by co-utilization of LDM, other mineral matrices (a zeolitized tuff), organic amendment (a commercial manure), and mineral fertilizer (urea, triple superphosphate, and potassium sulfate) for the growth of a pasture grass under controlled (pot) conditions. The evolution of nine different model proto-horizons (MPH) was monitored through a series of biochemical parameters and techniques (total/extracellular enzymatic activity, isoelectric focusing, and gas chromatography) to assess the potential of LDM in soil biochemical recovery.

Results and discussion

On the whole, treatments containing LDM resulted in good recovery of degraded soils, as shown by a general enhancement in biochemical functionality. Application of LDM increased the more stable fraction of organic matter and its active biochemical fraction, showing the highest stable humic carbon content and humic activity. Such outcomes seem to represent a long-term beneficial effect on soil functionality.

Conclusions

This study demonstrates that LDM could be a useful pedotechnomaterial (PTM) for improving the biochemical functionality of extremely degraded soils. Additionally, the use of LDM as a PTM has the ecological advantage of recycling what is often considered as a “waste material.” From a socioeconomic point of view, the reuse of LDM in pedotechnique could represent a new low-cost alternative to the complex and expensive management and disposal of this material.
  相似文献   
28.
A 7-year-old mixed breed spayed bitch (body weight: 10.6 kg) was presented with a history of intermittent episodes of seizures and untreated limb fracture. Appetite loss, nervousness, lateral recumbency, fasciculations, ataxia and poor nutritional condition were found. Venous blood gas analysis highlighted normal acid-base balance and severe low ionized calcium (0.58 mEq/L [range 1.13–1.32 mEq/L]). Marked total hypocalcaemia (6.4 mg/dL [range 8–10] or 1.6 mM [range: 2–2.5]) associated with hyperphosphoraemia (9.3 mg/dl [range 3.5–6.5 mg/dl]) displayed inverted ratio between minerals. ECG showed sinus arrhythmias. Circulating levels of Mg and Cu were within physiological range (1.97 mg/dl and 128 μg/dl respectively) and effects from interactions were excluded. Oral administration of calcitriol at 40 ng/kg/day led to clinical improvement within 48 hours, but circulating iCa levels were still below the lower limit of the reference range. Baseline levels of circulating parathormone (PTH) were 3 pg/ml, along with normal values of circulating vitamin D. Primary hypoparathyroidism was diagnosed as a chronic underlying condition triggered by pelvic fracture.  相似文献   
29.
The chemical investigation of an Indonesian specimen of Theonella swinhoei afforded four aurantosides, one of which, aurantoside J (5), is a new compound. The structure of this metabolite, exhibiting the unprecedented N-α-glycosidic linkage between the pentose and the tetramate units, has been determined through detailed spectroscopic analysis. The four obtained aurantosides have been tested against five fungal strains (four Candida and one Fusarium) responsible of invasive infections in immuno-compromised patients. The non-cytotoxic aurantoside I (4) was the single compound to show an excellent potency against all the tested strains, thus providing valuable insights about the antifungal potential of this class of compounds and the structure-activity relationships.  相似文献   
30.
The anti-proliferative effects of diatoms, described for the first time in copepods, have also been demonstrated in benthic invertebrates such as polychaetes, sea urchins and tunicates. In these organisms PUAs (polyunsaturated aldehydes) induce the disruption of gametogenesis, gamete functionality, fertilization, embryonic mitosis, and larval fitness and competence. These inhibitory effects are due to the PUAs, produced by diatoms in response to physical damage as occurs during copepod grazing. The cell targets of these compounds remain largely unknown. Here we identify some of the genes targeted by the diatom PUA 2-trans-4-trans-decadienal (DD) using the tunicate Ciona intestinalis. The tools, techniques and genomic resources available for Ciona, as well as the suitability of Ciona embryos for medium-to high-throughput strategies, are key to their employment as model organisms in different fields, including the investigation of toxic agents that could interfere with developmental processes. We demonstrate that DD can induce developmental aberrations in Ciona larvae in a dose-dependent manner. Moreover, through a preliminary analysis, DD is shown to affect the expression level of genes involved in stress response and developmental processes.  相似文献   
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