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31.
Specific antibodies to plasmid-encoded protein pgp3 are known to be encountered in human Chlamydia (C.) trachomatis infections. In order to verify whether antibodies to this protein could be developed in animals infected with plasmid-carrying chlamydial strains, 454 animal sera were examined using a home-made pgp3 protein ELISA and Western blots (WB) of recombinant pgp3 protein from Chlamydophila (Cp.) psittaci. Likewise, 50 human sera were tested by ELISA and WB of recombinant pgp3 from C. trachomatis. The reactivity against pgp3 protein was compared to the reactivity against chlamydial elementary bodies (EBs) detected by microimmunofluorescence (MIF) test. The presence of pgp3-specific antibodies was demonstrated in most ducks and pigeons with Cp. psittaci infection detected by MIF, as well as in the majority of symptomatic cats and pigs infected with Cp. felis and C. suis, respectively, which reacted at high titres to Cp. felis and C. suis EBs by MIF. Moreover, most of the sera collected from patients with C. trachomatis culture-confirmed infection and seropositive to C. trachomatis by MIF, presented antibodies specific to C. trachomatis pgp3 recombinant protein. Therefore, pgp3 protein could be a useful marker of chlamydial infections in animals, as well as in humans.  相似文献   
32.
The efficiency of Trametes versicolor laccase in the transformation of phenols (caffeic acid, catechol, hydroxytyrosol, methylcatechol, protocatechuic acid, syringic acid, m-tyrosol, 3-hydroxybenzoic acid, 3-hydroxyphenylacetic acid, 2,6-dihydroxybenzoic acid, 4-hydroxybenzaldehyde) usually present in waste water, such as that derived from an olive oil factory, was investigated. According to their response to 24 h laccase action the 11 phenolic compounds were classified in three groups: reactive (88-100% transformation), intermediate reactive (transformation lower than 50%), and recalcitrant (not transformed at all). The enzyme was able to transform the 11 substrates even when they were present in a mixture and also toward a phenolic extract from a Moroccan olive oil mill waste water (OMW) sample. The disappearance of protocatechuic, 3-hydroxyphenylacetic, and 2,6-dihydroxybenzoic acids, and 4-hydroxybenzaldehyde was enhanced whereas that of caffeic acid and m-tyrosol was depressed when the phenols were present in the mixture. A reduction of enzyme activity occurred in single and/or complex phenolic mixtures after enzymatic oxidation. No correspondence between phenol transformation and disappearance of enzymatic activity was, however, observed. The overall results suggest that laccases are effective in the transformation of simple and complex phenolic mixtures.  相似文献   
33.
Since 1988, geomorphologic research based on field surveys and photo-geological analysis, has been conducted in southern Tuscany (Italy), in areas characterised by very rapid morphological evolution. In the area outcrop Pliocene marine claystones uplifted during the Quaternary up to 750 m above sea level, now undergoing intense erosion processes, leading to considerable badlands formation. Morphodynamic analysis, conduced by direct and indirect measurements in a sample area, were taken in order to quantify the erosion rate in badland areas. The “Torrente Piantrafolla” sample area was chosen as representative of the study area; it was most recently monitored during the period Nov. 2000–Feb. 2004. At this time, morphographic and morphometric analyses carried out in selected measurement stations located on slopes, identified gravity as the main morphogenetic process responsible for slope shaping. The calanchi badland areas are characterised by constant and rapid shrinking of their edges resulting from landslides which occur in autumn and winter as a consequence of intense rainstorms. Selected measurement stations indicate an erosion rate value range from 5 to 7.5 cm/y. The comparison between 1976 and 1994 digital elevation models (DEM), obtained from photogrammetric restitution, indicated a mean erosion rate of about 5 cm/y in a nineteen year period. This value, considerably higher than the values measured in other Italian basins, indicate a very rapid evolution of the slopes, due mainly to small earth flows inside calanchi badlands.  相似文献   
34.
Proton high‐resolution magic angle spinning nuclear magnetic resonance (1H HR‐MAS NMR) has been applied for the analysis of two cultivars of durum wheat produced in different Italian geographical areas. Furthermore, on the same samples, isotopic ratios were measured by mass spectrometry (IRMS). The application of chemometrics to these results permitted the discrimination of semolina by cultivar and geographical origin. A similar approach has been applied to the results obtained from chemical analyses. The comparison showed that NMR spectroscopy can provide a faster method for the detection of differences among the durum wheat semolina according to geographical and varietal origin. Furthermore, IRMS data are suitable to provide information about the geographical origin of samples. This present investigation is part of an extensive research project to find a scientific method capable of classifying wheat foods for the assignment of a “denomination of origin” trademark.  相似文献   
35.
Nine Chlamydia suis isolates, obtained from pigs with conjunctivitis, were molecularly characterized by ompA sequencing and their in vitro susceptibility to six cathelicidin peptides (SMAP-29, BAC-7, BMAP-27, BMAP-27, BMAP-28, PG-1, LL-37) determined in cell culture. SMAP-29 was the most active peptide, reducing the intracellular inclusion number by > or =50% at a concentration of 10 microg/ml (3 microM) in six of the nine isolates tested. Three molecularly identical isolates were insensitive at a concentration as high as 80 microg/ml (25 microM). Of the remaining cathelicidin peptides tested, BAC-7 and BMAP-27 were active against six C. suis isolates at a concentration of 80 microg/ml (25 and 26 microM, respectively). Cathelicidins LL-37 and PG-1 did not show any anti-chlamydial activity at 80 microg/ml.  相似文献   
36.
Pectin methylesterase was purified from kiwi (Actinidia chinensis) and kaki fruit (Diospyros kaki). The pH values of the fruit homogenates were 3.5 and 6.2, respectively. The kiwi enzyme is localized in the cell wall and has a neutral-alkaline pI, whereas the kaki enzyme is localized in the soluble fraction and has a neutral-acidic pI. The molecular weights of the kiwi and kaki enzymes were 50 and 37 kDa, respectively. The two enzymes showed a similar salt and pH dependence of activity, and a different pH dependence of the inhibition by the kiwi proteinaceous inhibitor.  相似文献   
37.
The effects of storage at 4 degrees C on the quantity and quality of chemical components in the caviar from farmed Acipenser transmontanus have been analyzed by SEM, chemical methods, and NMR and MRI techniques. Particular attention has been focused on the lipid components, the distribution and mobility of which were strongly affected by the storage time. MRI and relaxation data indicated that lipids are endowed with two different mobility regimes, one slow (short T1) and one fast (long T1), both lengthening with the storage time. Chemical analysis assessed a total fat content that remained practically unchanged and a constant fatty acid composition during the total storage time. The combination of the two methods allowed one (a) to suppose that a mechanism of lipid hydrolysis (faster in unsalted than in salted eggs) is still occurring during storage of caviar at 4 degrees C for up to approximately 4 months and (b) to exclude that an intensive oxidative process is active in the same storage period.  相似文献   
38.
The evolution of modern eukaryotic phytoplankton   总被引:1,自引:0,他引:1  
The community structure and ecological function of contemporary marine ecosystems are critically dependent on eukaryotic phytoplankton. Although numerically inferior to cyanobacteria, these organisms are responsible for the majority of the flux of organic matter to higher trophic levels and the ocean interior. Photosynthetic eukaryotes evolved more than 1.5 billion years ago in the Proterozoic oceans. However, it was not until the Mesozoic Era (251 to 65 million years ago) that the three principal phytoplankton clades that would come to dominate the modern seas rose to ecological prominence. In contrast to their pioneering predecessors, the dinoflagellates, coccolithophores, and diatoms all contain plastids derived from an ancestral red alga by secondary symbiosis. Here we examine the geological, geochemical, and biological processes that contributed to the rise of these three, distantly related, phytoplankton groups.  相似文献   
39.
High-performance ion chromatography exclusion, inductively coupled plasma emission spectroscopy, and nuclear magnetic resonance (NMR) measurements were carried out in combination with chemometrics on 33 wine samples coming from three Slovenian wine-growing regions and from Apulia (southern Italy). The chemometric classification of wines according to their geographical origin was obtained with a nearly 100% degree of achievement. The discriminating potential of the (1)H NMR and of the other analytical determinations has been estimated separately. The best prediction of wines has been obtained with NMR data.  相似文献   
40.
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