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21.
In vitro maturation of vitrified immature germinal vesicle (GV) oocytes is a promising fertility preservation option. We analyzed the ultrastructure of human GV oocytes after Cryotop vitrification (GVv) and compared it with fresh GV (GVc), fresh mature metaphase II (MIIc) and Cryotop-vitrified mature (MIIv) oocytes. By phase contrast microscopy and light microscopy, the oolemmal and cytoplasmic organization of fresh and vitrified oocytes did not show significant changes. GVv oocytes showed significant ultrastructural alterations of the microvilli in 40% of the samples; small vacuoles and occasional large/isolated vacuoles were abnormally present in the ooplasm periphery of 50% of samples. The ultrastructure of nuclei and mitochondria-vesicle (MV) complexes, as well as the distribution and characteristics of cortical granules (CGs), were comparable with those of GVc oocytes. MIIv oocytes showed an abnormal ultrastructure of microvilli in 30% of the samples and isolated large vacuoles in 70% of the samples. MV complexes were normal, but mitochondria-smooth endoplasmic reticulum aggregates appeared to be of reduced size. CGs were normally located under the oolemma but presented abnormalities in distribution and matrix electron density. In conclusion, Cryotop vitrification preserved main oocyte characteristics in the GV and MII stages, even if peculiar ultrastructural alterations appeared in both stages. This study also showed that the GV stage appears more suitable for vitrification than the MII stage, as indicated by the good ultrastructural preservation of important structures that are present only in immature oocytes, like the nucleus and migrating CGs.  相似文献   
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Chemically stable di- and triacetyl derivatives of the natural o-diphenol antioxidant hydroxytyrosol were synthesized, and their chemical and biological antioxidant activities were assessed in comparison with that of the native synthetic compound. The chemical antioxidant activity of the selected compounds was evaluated by measuring the ferric reducing antioxidant power (FRAP). The data clearly indicate that, as expected, the hydroxytyrosol analogues, modified in the o-diphenolic ring, are devoid of any chemical antioxidant activity. On the contrary, both acetyl derivatives, at micromolar concentrations, equally protect against tert-butylhydroperoxide-induced oxidative damages in Caco-2 cells and human erythrocytes. This paper for the first time reports that chemically stable hydroxytyrosol acetyl derivatives, although devoid of chemical antioxidant activity, are as effective as the parent compound in protecting human cells from oxidative stress-induced cytotoxicity, after metabolization by esterases at the intestinal level, suggesting their possible utilization in either nutritional (functional food), cosmetic, or pharmaceutical preparations.  相似文献   
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Immature bitter orange fruit and its extracts have been introduced into the market as an alternative to Ephedra in weight loss products. However, the safety of the immature bitter orange fruit and its extracts is a debated argument due to the presence of synephrine, a constituent known as a sympathomimetic agent. In this paper, we describe the development of a new, rapid, and simple liquid chromatography-electrospray ionization-tandem mass spectrometry method devoted to the quantitative determination of synephrine in bitter orange samples, containing a high quantity of synephrine, and sweet orange samples, known to contain a low level of synephrine but at the same time being one of the main synephrine sources in a normal human diet. Two bitter orange dry extracts containing 5 and 6% sSynephrine and 10 sweet orange samples have been analyzed. Between the sweet orange samples, six were fresh oranges and four were fresh-squeezed juices; in these samples, the synephrine levels ranged from 0.00128 to 0.00349%.  相似文献   
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Veterinary Research Communications - Industrial chemical solutions are widely used as a method to disinfection of aquaculture water and environments. The aim of the present study was to evaluate...  相似文献   
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This paper reports the protective effect of the phenolic fraction extracted from extra virgin olive oils (OOPEs) against the cytotoxic effects of reactive oxygen species in human erythrocytes and Caco-2 cells, employed as model systems. Pretreatment of cells with various OOPEs, indeed, provides a remarkable protection against oxidative damages: this effect was strictly dependent on the o-diphenolic content of the extracts. Moreover, the protective effects observable in cellular systems were compared with in vitro antioxidant properties, measured by using the FRAP (ferric reducing/antioxidant power) assay; the reducing ability of OOPEs strictly parallels their o-phenolic content. The linear relationship demonstrated between biological effects and antioxidant capacity measured by the FRAP assay allows us to propose the use of this rapid colorimetric method in assessing and certifying the antioxidant power of extra virgin olive oil.  相似文献   
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Risks associated with mycotoxin contamination of cereals, that are included in the ten major staple foods and greatly contribute to the dietary energy intake, are of worldwide relevance. In small grain cereals, mycotoxins are produced by fungi such as Aspergillus, Penicillium, Alternaria and Fusarium that colonize the plant in the field and can grow during the post-harvest period, producing several classes of mycotoxins. The identification of mycotoxigenic fungal species and strains is essential for developing effective strategies for control. For this purpose, genetic traceability has proved to be a valuable tool that can be applied along the whole production chain, starting in the field for early diagnosis of FHB (Fusarium Head Blight) disease to the final processing steps, such as malting or pasta making. In this paper, DNA-based analytical tools that are currently available for the identification and quantification of mycotoxigenic fungal species and strains are reviewed, with particular emphasis on Fusarium, and their possible applications in mycotoxin control in small grain cereal chains are discussed.  相似文献   
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Italian pasta must be prepared using exclusively durum wheat. According to current Italian rules, only a maximum of 3% Triticum aestivum is allowed to account for cross-contamination that may occur during the agricultural process. Efficient methods for the detection of accidental or intentional contamination of common wheat to durum wheat products are therefore required. This article describes a novel approach for the detection and quantification of soft wheat adulteration in whole grain durum flours and dried pasta. The assay relies on the presence of intron-specific DNA length polymorphisms in the plant β-tubulin gene family, which can be highlighted through the PCR-based TBP (Tubulin-Based Polymorphism) method. In wheat, the TBP method produces species-specific amplification products, which can be either directly used as new DNA molecular markers capable of discriminating between T. aestivum and Triticum durum or analyzed at the sequence level for the design of species-specific probes. The latter approach allowed the development of new sequence-specific targets that can be exploited in RT-PCR assays for a rapid and accurate quantification of soft wheat adulteration in durum wheat pasta.  相似文献   
30.
In the absence of breeding strategy, natural spawning constitutes the breeding ground for fish farmers to empirically manage their commercial broodstock. In this context, we used six microsatellite markers to characterize the genetic pattern of six commercial seabream broodfish tanks having a common history spanning four generations. The progeny of one tank single‐day mass‐spawning event, reared in two different environments, was used to estimate the genetic parameters for body weight. Limited genetic differentiation was observed among broodfish groups. A panel of nine loci allowed us to unambiguously assign 95.4% of the offspring (1692) and identify 37 parents (65% of the total broodfish). The limited effective population size (Ne = 15.3) was due to the elevated variance of parental contributions and to broodfish failing to contribute to the progeny. The fluctuation of the allele frequency highlighted the risks of genetic drift and reduction in the heterozygosity in the next generations. Heritability for body weight was moderate at commercial size (0.40 ± 0.10) and the high genetic correlation at later stages laid the groundwork for precocious selection criteria for growth. The discussion opens on the opportunity to use mass spawning for selective breeding.  相似文献   
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