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41.
Background – The presence of important house dust and storage mite species in the microenvironment of atopic dogs has not been thoroughly investigated. Objectives – To compare the presence and population of five dust mite species (Dermatophagoides farinae, Dermatophagoides pteronyssinus, Acarus siro, Tyrophagus putrescentiae and Lepidoglyphus destructor) among households with mite‐sensitive atopic dogs (Group A), households with clinically healthy dogs (Group B) and households without pets (Group C, n = 25) in Greece. Animals – Twenty mite‐sensitive atopic dogs and 20 clinically healthy dogs. Methods – Dust samples were collected with a vacuum cleaner from owners’ mattresses (all groups) and from dogs’ sleeping areas (Groups A and B) or living room couch (Group C), once every season of the year. Following dust flotation, mites were counted and identified. Results – Dermatophagoides farinae was the most prevalent (60, 40 and 64% in Groups A, B and C, respectively), followed by D. pteronyssinus (45, 35 and 48%, respectively), whereas the three storage mites were found in fewer households. No major differences could be found between Groups A and B or between households with (Groups A and B) and without dogs (Group C) regarding the presence or numbers of the five dust mite species. Conclusions and clinical importance – The presence and population of five common house dust and storage mite species does not differ among Greek households with mite‐sensitive atopic dogs, households with healthy dogs and households without pets.  相似文献   
42.
The chitin-rich residues obtained from several industries have numerous applications in diverse fields such as biotechnology, pharmacology, medicine and agriculture. In this study, three different chitin-rich residues were evaluated with regard to enhancement of the chitinolytic activity of the mycoparasitic fungus Trichoderma harzianum, used for biological control of Fusarium oxysporum in greenhouse nurseries. Chitosan (CHIT), shrimp shell powder (SSP) and mushroom wastes (MW) activated the expression of the T. harzianum genes encoding the NAGase and chitinase activities (exc1, exc2, chit42, chit33 and chit37), the highest in vitro activities of T. harzianum being seen with MW. Under greenhouse nursery conditions, the treatments involving amendment with these residues and with T. harzianum increased the NAGase activity (between 5- and 20-times higher than peat) and the chitinase activity (between 3- and 6-times higher than peat) of the growing media and maintained the shoot dry weight of plants infected with F. oxysporum. Moreover, the incorporation of these residues into the growing media enhanced the growth (first leaf length, stem length and shoot dry weight) of muskmelon seedlings. The use of these residues with T. harzianum as amendments of growing media enhanced the growth of muskmelon seedlings and decreased the weight loss due to the pathogen, giving an added-value to these residues and enhancing their management.  相似文献   
43.
The Isavirus is an orthomyxovirus with a genome composed of eight segments of negative single-strand RNA (−ssRNA). It has been proposed that the eight genomic segments of the Isavirus are organized as a ribonucleoprotein (RNP) complex called a minigenome, which contains all the viral RNA segments, a viral heterotrimeric polymerase and multiple copies of the viral nucleoprotein (NP). Here, we develop an Isavirus minigenome system and show the importance of the formation of active RNPs and the role of viral NP R189, R194, R302 and K325 residues in the NP RNA-binding domain in the context of RNPs. The results indicate it is possible to generate a minigenome in salmon cells, a composite ISAV RNPs with EGFP-based chimeric vRNA with heterotrimeric polymerase (PB1, PB2, PA) and NP protein using CMV-based auxiliary plasmids. It was also shown that NP R189, R194, R302 and K325 residues are important to generate viral mRNA from the constituted RNPs and a detectable reporter protein. This work is the first salmon cell-based minigenome assay for the Isavirus, which was evaluated by a bioinformatic and functional study of the NP protein in viral RNPs, which showed that correct NP-vRNA interaction is key to the functioning of RNPs.  相似文献   
44.
The influence of essential fatty acids and cholesterol on the growth and survival of the Argentine shrimp Artemesia longinaris, was tested using experimental pelleted diets based on a standard diet. A series of diets were designed and prepared by adding cholesterol, pure oleic acid, raw linseed oil and fish oil (rich in fatty acids of the ω 3 series).After 30 days, no significant differences in growth were registered among the animals fed different rations, although significant differences in survival were found. The best survival was obtained with the diet supplemented with fish oil (87.3%). Survival of prawns fed the other diets was significantly lower (53.3–56.7%). Animals fed low fat diet, showed the lowest survival (30%).The results indicated the importance of cholesterol in the diet, and stressed the dietary necessity of highly unsaturated fetty acids of the linolenic acid series for the optimal survival of A. longinaris.  相似文献   
45.
The influence of control parameters (aeration, moisture, and C/N ratio) during composting of a municipal solid waste (MSW)-legume-trimming residue (LTR) mixture was studied at a pilot plant scale. Factors measured included the composition of the main volatile organic carbons (VOCs) emitted including limonene, β-pinene, 2-butanone, undecane, phenol, toluene, and dimethyl disulfide. Polynomial models were found to reproduce the experimental results with errors at less than 10%. The relative influence of the independent variables on temperature and selected VOCs followed the order: aeration > moisture > C/N. A high aeration rate results in higher (strong negative effect) values on selected VOCs emissions (41-71% on emitted VOCs variation). Moisture had a positive and negative effect depending on the selected VOCs. A high C/N ratio caused lower production of VOCs except for undecane and 2-butanone. Providing an aerobic environment (0.05 Lair kg(-1) min(-1)), high C/N ratios (>50), and medium moisture (55%) minimize emitted VOCs during MSW composting, ultimately resulting in less odors in the surrounding environment.  相似文献   
46.
Allophanic soil, natural and activated by acidification or calcination was used to adsorb organic recalcitrant compounds (lignin and chlorophenols) from biologically pre-treated kraft mill effluent. A synthetic non crystalline aluminosilicate like allophane coated with iron oxide (Al-Si-Fe) was used as control for comparison purposes. It was observed that the adsorption capacity of the allophanic soil increased at higher solid/solution ratio, and at lower pH values. The highest total phenolic compounds removal was obtained between pH 4.0 and 4.5 for natural and activated soil using a solid/solution ratio of 1:5, and for synthetic aluminosilicate using 300 mg in 30 mL of effluent solution. Soil activated by calcination procedure presented the highest total phenolic compounds adsorption capacity (71–85%) for untreated and aerobic or anaerobic pre-treated effluent. The specific chlorophenols analysis indicated that pentachlorophenol (PCP) was almost completely adsorbed onto the allophanic soil (> 99%), and that over 79% of the 2,3,4,6-tetrachlorophenol (TeCP) was adsorbed, independent of the biological pre-treatment type and the soil activation procedure. On the other hand, 2,4-dichlorophenol (DCP) coming from both aerobic and anaerobic treated effluent was poorly removed (24–30%) when natural soil was used for adsorption; whereas in calcinated and acidified soil DCP removal was more than 71%.  相似文献   
47.
Classical nova explosions are very energetic and frequent phenomena caused by explosive hydrogen burning on top of an accreting white dwarf. Observations of the recent nova V2487 Oph 1998 by the X-ray Multi-Mirror satellite (XMM-Newton) provide evidence that accretion (probably on a magnetic white dwarf) was reestablished as early as 2.7 years after the explosion. In addition, positional correlation with a source previously discovered by the R?ntgen Satellite (ROSAT) in 1990 suggests that the site of a nova explosion had been seen in x-rays before the outburst.  相似文献   
48.
49.
Navia  R.  Levet  L.  Mora  M. L.  Vidal  G.  Diez  M. C. 《Water, air, and soil pollution》2003,148(1-4):323-333
Bleached Kraft mill effluent was treated in an activated sludgereactor followed by an allophanic soil adsorption system (ASAS). Under aerobic conditions, removal efficiencies of biological oxygen demand (BOD5) and chemical oxygen demand (COD) varied between 57.7–96.5% and 30.3–57.0%, respectively, depending on the hydraulic retention time (HRT). On the other hand, tannin-lignin and phenolic compounds removal efficiencies attained values between 13.2–51.2 and 3.6–33.5%,respectively. An allophanic soil adsorption system was designed for color and phenolic compounds removal. Three different types of soils were used: Natural allophanic soil as the control compared, with calcinated and acidified allophanic soil. The initial removal efficiencies for phenolic compounds varied between 72 an 87% for activated soils, while color initial removal efficiencies were between 95 and 99%. Moreover, COD and tannin-lignin initial removal efficiencies reached maximum values of 74 and 87%, respectively, for calcinated soil. Design parameters show that there is an enhancement factor in adsorption capacities for both activated soils. In fact, phenolic compounds breakpoint adsorption capacity increased 5.3 times for calcinated soil and 17.6 times for acidified soil, while saturation capacity increased between 2.2 and 3.2 times. In addition, color breakpoint adsorption capacity increased 2.8 times for calcinated soil and 10.4 times for acidified soil, while saturation capacity increased between 3.2 and 5.5 times.  相似文献   
50.
The contribution of root morphology to enhanced uptake of heavy metals by hyperaccumulating plants is not well understood. The objective of this study was to describe root‐morphological characteristics of the natural nickel (Ni) hyperaccumulator Thlaspi goesingense Hálácsy. Plant samples were collected from a serpentine site near Redlschlag (East Austria), characterized by large soil Ni concentrations. Roots were evaluated for mass, length, surface area, diameter, and related ratios using an image‐analysis approach. Results showed that on the indigenous site, T. goesingense Hálácsy developed a fine‐branched root system, confined within a shallow soil depth. Coarse roots (>1 mm) accounted for about 60% of the total root mass (fresh and dry), while their contribution to the surface area and especially to the length of the system was small. Conversely, fine roots (<1 mm) represented 99% of the total root length and 88% of the surface area. The largest proportion of root length and area was found in the smallest diameter class of 0.0 to 0.5 mm. Shoot‐biomass production per unit root was high, in spite of the adverse soil conditions. Roots accounted for 8% of the total plant mass and about 4% of the total Ni accumulation. We conclude that the root system of natively grown T. goesingense Hálácsy exhibits a potential for enhanced Ni extraction from soil, since it mainly consists of very fine roots with extended absorptive area.  相似文献   
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