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471.
GIS‐based ecological risk assessment for contaminated sites by fish farm effluents using a multicriteria weight of evidence approach 下载免费PDF全文
Claudio Silva Eleuterio Yáñez María Laura Martín‐Díaz Tomás Angel DelValls 《Aquaculture Research》2016,47(2):524-539
In this study, an integrative weight of evidence (WOE) tetrad methodology was developed and used to assess environmental quality and ecological risk at contaminated sites by fish farm effluents using spatial modelling tools [geographical information systems (GIS) and fuzzy logic and multicriteria analysis (MCA)], taking into account the results of four lines of evidence (LOE): the physico‐chemical characteristics of water and sediment, acute toxicity bioassays, biomarkers and the in situ alteration of benthic communities. The methodology was tested in the Rio San Pedro salt marsh creek in southwestern Spain. The proposed approach allowed for a quantitative spatial characterization of ecological risk and a better discrimination based on various types of physical, chemical and biological data. The methodology illustrates how GIS spatial models may be used in conjunction with other tools such as fuzzy logic and MCA to assist in decision‐making processes based on multiple environmental quality criteria and lines of evidence, with the transparency, objectivity and synoptic ability required to address environmental management problems in general and the management of contaminated marine areas affected by fish farms in particular. 相似文献
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Erika Cottone Valentina Pomatto Fulvio Cerri Ezio Campantico Ken Mackie Massimiliano Delpero Alda Guastalla Claudio Dati Patrizia Bovolin Maria Fosca Franzoni 《Fish physiology and biochemistry》2013,39(5):1287-1296
Cannabinoids, the bioactive constituents of Cannabis sativa, and endocannabinoids, among which the most important are anandamide and 2-arachidonoylglycerol, control various biological processes by binding to specific G protein-coupled receptors, namely CB1 and CB2 cannabinoid receptors. While a vast amount of information on the mammalian endocannabinoid system does exist, few data have been reported on bony fish. In the goldfish, Carassius auratus, the CB1 receptor has been cloned and its distribution has been analyzed in the retina, brain and gonads, while CB2 had not yet been isolated. In the present paper, we cloned the goldfish CB2 receptor and show that it presents a quite high degree of amino acid identity with zebrafish Danio rerio CB2A and CB2B receptors, while the percentage of identity is lower with the puffer fish Fugu rubripes CB2, as also confirmed by the phylogenetic analysis. The sequence identity becomes much lower when comparing the goldfish and the mammalian CB2 sequences; as for other species, goldfish CB2 and CB1 amino acid sequences share moderate levels of identity. Western-blotting analysis shows the CB2 receptor as two major bands of about 53 and 40 kDa and other faint bands with apparent molecular masses around 70, 57 and 55 kDa. Since the distribution of a receptor could give information on its physiological role, we evaluated and compared CB1 and CB2 mRNA expression in different goldfish organs by means of qReal-Time PCR. Our results show that both CB1 and CB2 receptors are widely expressed in the goldfish, displaying some tissue specificities, thus opening the way for further functional studies on bony fish and other nonmammalian vertebrates. 相似文献
477.
Domenico Rongai Claudio Cerato Luca Lazzeri Sandro Palmieri Giampiero Patalano 《Journal of pest science》2008,81(4):179-185
During laboratory tests, mineral oil in water emulsion (2%), containing Brassicaceae seed meals (2 g l−1), induced total mortality (100%) among adult female California red scales on detached orange fruits, whereas only 47.5% of
insect mortality was observed with the same mineral oil when used alone. These results were partially confirmed by two preliminary
field trials. With the aim of improving biodegradability and the environmental impact of the insecticidal formulation, mineral
oil was replaced by a vegetable oil without observing any significant variation of the product’s efficacy. In addition, a
clear “dose-effect” of meal in mineral and vegetable oil was also demonstrated. The formulation, essentially based on oil,
meals and some minor additives, shows the following advantages: (1) high insecticidal activity against an insect pest difficult
to control such as Aonidiella aurantii (Maskell); (2) simultaneous control of several pathogens seems to be possible; (3) non-appearance of resistance phenomena
in plant pathogens; and finally, (5) absence of phytotoxicity. 相似文献
478.
In fruit trees, understanding genetic determinisms of architectural traits is considered as a promising manner to control
vegetative development and yield regularity. In this context, our study aimed to classify 2-year-old apple hybrids on the
basis of their architectural traits. From a fine phenotyping, trees were described as tree graphs, including topological and
geometric information. To evaluate the similarity between trees, comparison methods based on edit operations (substitution,
insertion and deletion) were carried out. Distance between two tree graphs was computed by minimising the sum of the costs
of the edit operations applied to transform one tree into another. Two algorithms for the comparison of unordered and partially
ordered tree graphs were applied to a sub-sample of the population, taking into account several geometric attributes. For
each comparison, a dissimilarity matrix was computed, and subsequently trees were clustered. A local interpretation of the
matched entities was proposed through schematic representations of the trees, and similarities between trees were analysed
within and between clusters. The tree graphs, both unordered or partially ordered and whether the attributes were considered
or not, were grouped, by clustering, according to the number of entities per tree. The robustness of the unordered comparison
was demonstrated by its application to the whole population, since it provided results similar to those obtained on the sub-sample.
Further developments towards a higher relative weight of geometric versus topological information are discussed in the perspective
to define an architectural ideotype in apple. 相似文献
479.
Anfossi L Calderara M Baggiani C Giovannoli C Arletti E Giraudi G 《Journal of agricultural and food chemistry》2008,56(6):1852-1857
The official methods for the quantification of aflatoxin M1 in dairy products (cheese and yogurt) include extraction into dichloromethane or chloroform, evaporation of the solvent, partitioning of the reconstituted residue with hexane, and subsequent analysis. To secure a rapid and inexpensive screen for aflatoxin M1 contamination, a sensitive competitive ELISA, using a rabbit polyclonal antibody, was developed for measuring aflatoxin M1 in milk and used in a comparative study for measuring the extraction efficiency of aflatoxin M1 in aqueous or organic solvent buffers using yogurt samples. An aqueous sodium citrate solution was found to be suitable for extracting aflatoxin M1, thus eliminating the need for organic solvents. The citrate extraction proved to be efficient (recovery ranged from 70 to 124%) in fortified samples of very different kinds of dairy products, including yogurt and six types of cheese. Fourteen yogurt and cheese samples were extracted with citrate solution and analyzed by ELISA. A good correlation was observed (y=0.95x-0.59, r2=0.98) when the data were compared with those obtained through the official method, across a wide range of aflatoxin M1 contaminations (10-200 ng/kg). 相似文献
480.
Tanja Mimmo Luciano Cavani Riccardo Reggiani Claudio Marzadori Carlo Gessa 《Biology and Fertility of Soils》2008,44(3):521-526
This study investigated the interactions of CrIII and CrVI present as free metal ions or as organic CrIII (Cr-L) with a Ca-polygalacturonate
(Ca-PG) network. Ca-PG networks were treated with solutions of chromium (CrIII and CrVI) at different concentrations at three
different pH values. The Cr-L complex were obtained by water extraction of hydrolysed leather. The CrVI had almost no interaction
with the Ca-PG networks, whereas CrIII as a free metallic ion was strongly retained by the network. The calculated Langmuir
adsorption isotherms showed a twofold increase in maximum CrIII adsorption but a decrease in the affinity of the metal with
the Ca-PG networks. This would indicate that the different chromium species, i.e. CrIII and its hydrolytic species, interact
in a different way with the polygalacturonate chains. In addition, thermal analysis showed that CrIII sorption modified the
structure of the network. These modifications were reduced, and thermal stability increased if Ca-PG adsorbed Cr-L or L. Furthermore,
the treatment of Ca-PG with hydrolysed leather water extract-reduced CrIII sorption by 94%. The hydrolysed leather fraction
immobilized onto the Ca-PG networks probably consisted of peptides and could therefore represent an important source of organic
N. 相似文献