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Although the use of stable transformants is indispensable to elucidate mechanisms underlying molecular plant–pathogen interactions, this approach remains difficult to apply to crops. Alternatively, biolistic transformation has often been used as a transient expression method in various plants. In this study, we developed a method for in situ biolistic transformation without separating leaves from barley seedlings by using a hand-held particle bombardment system because unwounded leaves are preferable for analyzing interactions between barley and Blumeria graminis f. sp. hordei which requires healthy living cells. As a result, we found that the infection rate in intact leaves was higher than in separated leaves and that the transformation efficiencies in leaves were higher when plants were grown in vermiculite rather than in culture soil. Furthermore, we determined the appropriate inoculation time after bombardment to analyze the incompatible interaction and successfully monitored the gradual occurrence of cell death over time. Our system was suitable for relatively long-term follow-up analysis of the fate of each single cell during plant–pathogen interactions.  相似文献   
33.
In this study, we evaluated the feasibility for the use of digested slurry from livestock manure (hereafter, slurry) in paddy fields through field experiments conducted in Southern Vietnam. The pouring method for slurry was used, and a vacuum truck was used for transportation and pouring of the slurry. A prototype slurry tanker was manufactured for transportation and application of slurry, because vacuum trucks are rarely available in rural areas of Vietnam. For evaluation of feasibility, costs and labor for application of slurry and rice production were examined and compared with conventional cultivation methods using chemical fertilizers. As the results, rice production with the use of slurry was 485 g m?2, which is within the range of on-site conventional cultivation, so slurry may be a good substitute for chemical fertilizers in rice production. Costs for slurry fertilization with a prototype slurry tanker and a vacuum truck were estimated at 0.13 USD m?2 and 0.10 USD m?2, respectively. These costs were higher than for conventional cultivation of 0.06 USD m?2 under the present conditions with T-N concentrations of approximately 400 mg L?1 in the slurry. However, we clarified that the cost for slurry fertilization can be lower than conventional cultivation when the concentrations of nitrogen in slurry increase from 400 to 2000 mg L?1. These results show that an increase in nitrogen concentrations in slurry make slurry fertilization feasible if the amounts of water for washing livestock sheds that enter into the biogas digesters are reduced.  相似文献   
34.
As diamond-producing catalysts, 12 transition metals such as iron, cobalt, and nickel were first reported by General Electric researchers more than 30 years ago. Since then, no additional elemental catalyst has been reported. An investigation of the catalytic action of group V elements is of great interest from the viewpoint of producing an n-type semiconducting diamond crystal. In the present study, diamond was synthesized from graphite in the presence of elemental phosphorus at high pressure and temperature (7.7 gigapascals and 1800 degrees C). Furthermore, single-crystal diamond was grown on a diamond seed crystal.  相似文献   
35.
The purpose of this study was to investigate the minimum effective dose of recombinant canine interferon-γ (rCaIFN-γ) for the treatment of dogs with atopic dermatitis (AD). Thirty-four dogs with AD from 17 animal hospitals in Japan were administered half or one-fifth of the approved rCaIFN-γ dose of 10 000 units/kg, three times a week for 4 weeks, followed by once weekly for an additional 4 weeks. Pruritus, excoriation, erythema and alopecia were evaluated and scored by the investigators on weeks 2, 4, 6, 8 and 12. The efficacy rate (number of excellent cases + number of good cases/total number of cases) at week 8 in the 2000 units/kg group was 36.4% for pruritus, 36.4% for excoriation, 45.5% for erythema and 36.4% for alopecia. In contrast, in the 5000 units/kg group, the efficacy rate was 64.3% for pruritus, 57.1% for excoriation, 78.6% for erythema and 78.6% for alopecia. The efficacy rate of the 5000 units/kg group was high for all signs evaluated and comparable to that of the 10 000 units/kg group reported in a previous study. The results of this study showed that 2000 units/kg of rCaIFN-γ is less effective than 5000 units/kg to treat dogs with AD, and the efficacy of the 5000 units/kg dose is comparable to that of 10 000 units/kg at week 8.  相似文献   
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The purpose of this study was to evaluate the histopathologic changes seen in feline plasmacytic pododermatitis in an attempt to correlate clinical response with any specific histopathologic feature, and to evaluate these specimens for possible infectious organisms. Fourteen skin biopsies from cats with plasmacytic pododermatitis and a clinical follow-up of 12–36 months were included in the study. Sections were stained with H&E as well as with a polyclonal anti- Mycobacterium bovis [Bacille Calmette–Guerin (BCG)] antibody cross-reactive to a broad spectrum of fungi and bacteria. Sections stained with the anti-BCG antibody were graded as positive or negative. Inflammatory cell types and density, overall pattern, and the presence or involvement of adnexal structures were assessed in sections stained with H&E. All sections were negative for organisms within the actual footpad tissue with the anti-BCG antibody stains. Two samples revealed a few foci of cocci on the outer surface of the ulcers.
Funding: Self-funded.  相似文献   
38.
When fungal germlings, after forming haustoria of Blumeria graminis f. sp. hordei (B. graminis), were removed from the surfaces of barley coleoptiles by cellulose acetate, followed by challenge inoculation with the non-pathogen Erysiphe pisi, they infected the nonhost barley coleoptile cells. This phenomenon was not observed on the coleoptile surface when the fungal germlings of B. graminis were removed before the formation of haustoria. Also, when the surface was inoculated with the pathogen of barley B. graminis as a challenger, after removing the fungal germlings of inducer post haustorial formation, the penetration efficiency of the fungi increased significantly compared with that of the control. Furthermore, when we extracted the crude-susceptibility inducing factor (suppressor) from coleoptiles before and after the formation of haustoria of B. graminis, suppressor activity against infection with E. pisi was observed only in the extract of barley coleoptiles that included haustoria of B. graminis about 18 h or later after inoculation. Surprisingly, however, the extract did not increase the penetration efficiency of B. graminis significantly. Thus, we hypothesize that the suppressor extracted from barley coleoptiles in which B. graminis had formed haustoria has no effect on increasing the penetration efficiency of the primary infection from the appressorium of B. graminis but has an effect on the infection with non-pathogen E. pisi.  相似文献   
39.
Phakopsora pachyrhizi, the cause of soybean rust, is an economically important pathogen of soybean in South America. Understanding the pathogenicity of indigenous fungal populations is useful for identifying resistant plant genotypes and targeting effective cultivars against certain populations. Fifty-nine rust populations from Argentina, Brazil, and Paraguay were evaluated for pathogenicity in three cropping seasons, 2007/2008–2009/2010, using 16 soybean differentials. Only two pairs of P. pachyrhizi populations displayed identical pathogenicity profiles, indicating substantial pathogenic variation in the rust populations. Comparative analysis of 59 South American and five Japanese samples revealed that pathogenic differences were not only detected within South America but also distinct between the P. pachyrhizi populations from South America and Japan. In addition, seasonal changes in rust pathogenicity were detected during the sampling period. The differentials containing resistance genes (Rpp: resistance to P. p achyrhizi) Rpp1, Rpp2, Rpp3, and Rpp4, except for Plant Introduction (PI) 587880A, displayed a resistant reaction to only 1.8–14, 24–28, 22, and 36 % of South American P. pachyrhizi populations, respectively. In contrast, PI 587880A (Rpp1), Shiranui (Rpp5), and 3 Rpp-unknown differentials (PI 587855, PI 587905, and PI 594767A) showed a resistant reaction to 78–96 % of all populations. This study demonstrated that P. pachyrhizi populations from South America vary geographically and temporally in pathogenicity and that the known Rpp genes other than Rpp1 in PI 587880A and Rpp5 have been less effective against recent pathogen populations in the countries studied.  相似文献   
40.
Biological denitrification experiment was conducted using sugar-industry wastes, namely final molasses as a carbon source and bagasse charcoal pellets as supporting media for denitrifying bacteria. We employed an upflow fixed-bed reactor filled with the pellets and biofilm attached onto them. This was fed with potassium-nitrate and dilute-molasses solutions. Total nitrogen removals of more than 85% were achieved at influent carbon–nitrogen (C/N) ratios between 2 and 4, and hydraulic residence times of more than 0.8 h. This demonstrated that final molasses could be used as an alternative carbon source. On the other hand, final molasses also contained some organic/ammonium nitrogen and refractory organic matter including colors, both of which were difficult to remove with the reactor. Accordingly, at higher C/N ratios, these substances caused major increases in effluent total-nitrogen and organic-carbon concentrations. Therefore, an optimum C/N ratio was found to be around 2.  相似文献   
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