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991.
Aurelija Samuiloviene Antanas Kontautas Riho Gross 《Fish physiology and biochemistry》2009,35(4):649-659
The genetic diversity and differentiation of sea trout were studied in three river basins in Lithuania: Akmena-Dane, Bartuva,
and Nemunas. A total of 282 individuals were genotyped at eight microsatellite loci. A similar level of genetic diversity
was found in all of the populations studied: mean allelic richness ranged from 3.64 to 5.03, and average expected heterozygosity
ranged from 0.588 to 0.721. Significant genetic divergence was observed among the different river basins as well as between
populations within the drainages. All pairwise F
ST values were highly significant, ranging from 0.027 to 0.197. The analysis of molecular variance showed rather weak hierarchical
population structuring within the Nemunas basin, which may be explained by extensive gene flow among different river basins
or, alternatively, reflect the influence of artificial breeding. Information on genetic diversity and differentiation of the
Lithuanian sea trout populations will be useful for future management decisions. 相似文献
992.
Thomas H. Galley Frederico M. Batista Richard Braithwaite Jon King Andy R. Beaumont 《Aquaculture International》2010,18(3):315-325
The blue mussel Mytilus
edulis is a commercially important species whose fishery and culture generally relies on natural spat collection. Hatchery-production
could provide an alternative source of seed, enabling reliable expansion of the industry. Mussel spawning and larval rearing
trials were carried out to optimise elements of hatchery production. Culturing fertilised eggs at low density (20–200 eggs cm−2) rather than high density (400–720 eggs cm−2) significantly improved the quality of first veliger larvae and differences in this improvement were evident between the
eggs from different females (maternal effects). Veliger larval growth at 17 or 21°C was significantly faster than growth at
14°C. Feeding veliger larvae an identical total ration either daily or at 2–3 day intervals did not significantly affect their
growth. Different microalgal diets (1: Isochrysis sp. (clone T-ISO), 2: Chaetoceros
calcitrans forma pumilus, 3: C. muelleri, 4: mixed Isochrysis sp. (clone T-ISO) and C. calcitrans f. pumilus, and 5: mixed Isochrysis sp. (clone T-ISO) and C. muelleri) were tested on veliger larval growth and mixed diets outperformed single-species diets. 相似文献
993.
Issei Nishiki Mikiko Furukawa Sho Matui Toshiaki Itami Toshihiro Nakai Terutoyo Yoshida 《Fisheries Science》2011,77(3):367-373
In Japan, Lactococcus garvieae infection has been the main fish disease in aquaculture. Although commercial oral and injectable vaccines have been used
to prevent L. garvieae infection in Japan, L. garvieae has been isolated not only from unvaccinated fish but also from vaccinated fish in which immunity induced by vaccination
had diminished. In order to obtain epidemiological information on this fish pathogen, we conducted biased sinusoidal field
gel electrophoresis (BSFGE) pattern analysis and phage typing of L. garvieae isolates (n = 427) from fish in Japan. These isolates were obtained from 13 different fish species between 1980 and 2007. In the BSFGE
analysis, L. garvieae isolates were classified into 17 groups (S1–S17) based on the SmaI digestion patterns and into four groups (A1–A4) based on the ApaI digestion patterns. Phage typing revealed five different phage susceptibility profiles (A–E) in L. garvieae isolates. Since 2005, comparisons of the results of phage typing and BSFGE have indicated the presence of a novel genotype
(S16/A4) with phage type E. All the strains belonging to this type showed lincomycin sensitivity. 相似文献
994.
Poly(vinyl alcohol) (PVA)/Ag-zeolite nanofiber webs were prepared with different concentrations of Ag-zeolite nanoparticles
by the electrospinning technique. Scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), transmission
electron microscopy (TEM), Fourier transform-infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), differential
scanning calorimetry (DSC), Instron, and antibacterial activities analysis were utilized to characterize the morphology and
properties of the PVA/Ag-zeolite nanofiber webs. The study results showed that the polymer concentration, applied voltages
and tip-to-collector distances were the main factors influencing the morphology of the electrospun nanofiber webs. The introduction
of Ag-zeolite nanoparticles improved the mechanical properties and thermal stability of the PVA nanofiber webs. TEM data demonstrated
that the Ag-zeolite nanoparticles were well distributed within the nanofiber. FTIR revealed a possible interaction between
the PVA matrix and the Ag-zeolite nanoparticles. These fibers showed an antibacterial efficacy of 99.8 % and over against
Staphylococcus aureus and Klebsiella pneumoniae at Ag-zeolite concentrations of 1 % and over, because of the presence of the
silver nanoparticles in the zeolite. 相似文献
995.
We prepared solid polymer electrolytes (SPEs) composed of poly(ethylene glycol) monomethyl ether acrylate (1A9OMe) and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIm][OTF]) and 1-ethyl-3-methylimidazolium bis(trifluoromethane sulfonyl) imide ([EMIm][TFSI]) as the ionic liquid. The SPEs formed by appropriately adding ionic liquids in the 1A9OMe prior to thermal cure. The ratio of 1A9OMe and ionic liquid was 1:9, 3:7, and 5:5, respectively. The characterization of solid polymer electrolytes were investigated using Fourier transform infrared spectroscopy in the attenuated total reflectance mode (FTIR-ATR), Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and glavanostatic charge-discharge test. The highest ionic conductivity of SPEs was found to be 4.90×10?4 S/cm in a 1A9OMe/[EMIm][OTF] of 3:7. As IL contents were increased, the specific capacitance of supercapacitor was increased. The specific capacitance of supercapacitor for ionic liquid with large ion size was lower than that for ionic liquid with smaller ion size. 相似文献
996.
A new series of magenta dyes having different length of alkyl substituents was synthesized to dye unmodified polypropylene (PP) and ultra-high molecular weight polyethylene (UHMWPE) fiber. It could be concluded that the affinity of the dyes onto unmodified PP and UHMWPE fibers was increased with the increase of the length of alkyl substituents. The optimum length of alkyl group was determined as the longest dodecyl-substituted dye in this study. Their absorption spectra appeared almost the same at visible range, which meant that the length of alkyl substituents did not affect the color appearance of the dyes. The color fastness properties of the dyeings to washing, rubbing and light were good enough for commercialization. 相似文献
997.
Mohamed Aït Hamza Nadine Ali Johannes Tavoillot Odile Fossati-Gaschignard Hassan Boubaker Abdelhamid El Mousadik Thierry Mateille 《BMC ecology》2017,17(1):41
Background
Root-knot nematodes (RKN) are major pest of olive tree (Olea europaea ssp. europaea), especially in nurseries and high-density orchards. Soil samples were collected from main olive growing areas of Morocco, to characterize Meloidogyne species and to discuss the contribution of biotic and abiotic factors in their spatial distribution.Results
RKN were found in 159 soil samples out of 305 from nurseries (52.1% occurrence) and in 11 out of 49 soil samples from orchards (23.2% occurrence). Biochemical and molecular characterisation (PAGE esterase and SCAR) revealed the dominance of M. javanica both in nurseries and orchards with minor presence of M. incognita only in nurseries, and M. arenaria in only one nursery. RKN were distributed on aggregated basis. Frequent presence of M. javanica in orchards might have come from nurseries. In contrast, the detection of M. incognita in nurseries alone suggests that this species could not reproduce in orchards because of either the competition with other plant-parasitic nematodes or unfit local habitats. The impact of environmental variables (climate, habitat origin and physicochemical characteristics of the substrates) on the distribution of Meloidogyne species is also discussed.Conclusion
Olive nurseries in Morocco are not able to guarantee the safety of rooted plants. As a result, olive production systems are exposed to strong RKN invasion risks. Consequently, the use of healthy substrates in nurseries may prevent plant-parasitic nematode induction in orchards.998.
Electrospun web may possibly be widely applied to protective garments or specialty textiles due to its high level of protection
as well as comfort. Of particular interest in this study is to develop waterproof-breathable fabric by applying electrospun
web of polyurethane directly onto the substrate fabric. The optimal electrospinning condition was examined with regards to
the concentration, applied voltage and tip-to-collector distance. Solvent-electospinning of polyurethane was performed at
the optimum condition, using N,N-dimethylacetamide as solvent. The thickness of 0.02 mm of electrospun web was applied onto
the polyester/nylon blended fabric. For comparison, the polyester/nylon fabrics were coated with 0.02 mm thickness of polyurethane
resin membranes adopting four different conditions. The electrospun PU web/fabric was compared to resin coated fabrics in
terms of water-proof and breathable properties. The electrospun web applied fabric showed higher air permeability, vapor transmission,
and thermal insulation properties than resin coated fabrics, which can be translated as greater comfort sensation of electrospun
applied fabrics. However, water resistance value of electrospun web applied fabric did not reach that of resin coated fabrics. 相似文献
999.
Pandino G Lombardo S Mauromicale G 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):291-297
The globe artichoke is a widely consumed vegetable in the Mediterranean Basin, with Italy being the leading producer. In southern
Italy, its cultivation contributes to local economic stability and social development. The producers are increasingly choosing
to replace autochthonous varieties, such as ‘Violetto di Sicilia’, with cultivars bred or selected outside of the region,
putting pressure on the maintenance of traditional varieties. Here, we have undertaken a detailed morphological and chemical
analysis of a group of clones selected from a population of ‘Violetto di Sicilia’. All the traits measured displayed genetic
variation, particularly the total content of phenolics and minerals. The capitula of the ‘Violetto di Sicilia’ clones contained,
on average, 6.3 g kg−1 of fresh weight total phenolics, compared with 4.5 g kg−1 in the two commercial varieties. The clones also had more inulin than commercial varieties (254 vs. 225 g kg−1 of dry matter), as well as a good mineral content. The set of clones is of interest in the context of the proposed improvement
of the crop through breeding and selection of genotypes with high nutritional quality and a specific end-use (industrial processing
or fresh consumption). 相似文献
1000.
Hilda Karuppiah Nithya Kirubakaran Janarthanan Sundaram 《Genetic Resources and Crop Evolution》2018,65(1):79-90
Pulses, the most important source of high-quality dietary proteins are prone to serious damage due to insect pests, of which 20–25% damage was inflicted by stored product bruchid pest, Callosobruchus maculatus (F.). An alternative approach to control these insect pests apart from fumigation is the use of primary metabolites involved in plant defense mechanism. In the present study, one of such molecule, an insect anti-metabolic protein, arcelin was screened from nine different wild and cultivated varieties of pulses. Insect feeding bioassay with C. maculatus revealed that seven of these seed varieties were not infested by the bruchid insect pest. Additionally, the presence of arcelin polypeptide subunits (27–42 kDa) was demonstrated in the seeds of Phaseolus limensis L. and Phaseolus lunatus L. whereas, an insignificant amount was observed in Lablab purpureus L. Besides, seed kernel extract of P. lunatus registered a highest HA activity against native human-A erythrocytes and this activity was increased to several fold when the erythrocytes were treated with proteolytic enzymes revealing the characteristic feature of arcelin. Similarly, HA activity was observed when rat and mouse erythrocyte was treated with pronase, whereas, no titer value was observed upon treatment with its native erythrocytes. Of the 24 carbohydrates tested, only acetylated amino sugar, N-acetyl-d-galactosamine inhibited the agglutinating activity of crude seed extract against human-A RBC. Among the three glycoproteins tested, none were found potential to competitively inhibit the agglutination activity against human-A erythrocytes. Overall, this study reveals the presence of arcelin, an anti-metabolic insecticidal protein in seeds of P. lunatus. 相似文献