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41.
Protocol EN 1786 for the detection of irradiated food by electron spin resonance (ESR) spectroscopy was not conceived for the detection of irradiated bone-containing ingredients included in low concentration in non-irradiated food. An enzymatic hydrolysis method, realized at 55 degrees C, has been developed for the extraction of the bone fraction. When followed by a purification of the extracts by an aqueous solution of sodium polytungstate, this method made possible the detection of irradiated mechanically recovered poultry meat at very low inclusions (0.5%, wt/wt by ESR) in various meals (quenelles and precooked meals).  相似文献   
42.

Context

The knowledge of consumer preferences in wood furniture is crucial for the wood processing industries.

Aim

This study aims to identify the attributes of wood that affect the preferences of consumers from the city of Antananarivo, Madagascar, for wooden furnishings.

Methods

Quantitative measurements of the density and aesthetic properties of 12 wood species were carried out. The properties measured were the colour in the CIEL*a*b* colour space, the texture through greyscale image processing, and the density. Then, the wood specimens were subjected to sensory analysis with 100 consumers.

Results

The results showed that the "density" was a prime criterion in choosing a wood species. Concerning the visual aspect, Antananarivo consumers generally liked slightly dark wood colour (L* around 52), tending towards yellow, with a visible oriented texture. The influence of socio-economic factors was also highlighted.

Conclusion

These results are of prime importance in the search for alternative species to replace precious woods that are becoming rare.  相似文献   
43.
The aim of this study was to show and compare the as yet unknown microbiological and biochemical composition of ??adjuevan??, an Ivorian traditional salted fermented fish that is produced by two main processing methods and consumed for its flavor. Method 1 uses the full fish and method 2 uses fish fillets. The pH was around 6 and the major organic acids were acetic and butyric acids in all adjuevan samples. The free amino acid profile varied according to the fermentation method, although the major free amino acids were valine, leucine, alanine, aspartic acid and glutamic acid, ranging in concentration from 101.7 to 745.4?mg/100?g, for both methods. Adjuevan produced using method 1 had the best composition of free amino acids. Lactic acid bacteria counts were between 6.0?×?104 and 2.6?×?105?cfu/g for method 1 and 5.9?×?103 and 2.1?×?104?cfu/g for method 2. Yeasts were detected in all samples. Microbial ecology analysis using PCR-denaturing gradient gel electrophoresis (DGGE) revealed the presence of more bacterial species than previously reported in fermented fish. Bacterial species varied according to fermentation method. Species such as Staphylococcus xylosus, S. lentus, S. saprophyticus, and Bacillus megaterium were found only in samples produced by method 1, while those of Staphylococcus piscifermentans, Bacillus mycoides, and Corynebacterium xerosis were found only in samples produced by method 2. Using specific primers, we detected several lactic acid bacteria (LAB), such as Lactobacillus, Pedicoccus, Lactcoccus, Streptococcus, and Leuconostoc species; the composition these bacteria in adjuevan samples varied according to the preparation method, but were not found to be dominant. We conclude that the molecular PCR-DGGE method can be used to differentiate fermentation methods by LAB profile analysis. A mixture of strains of S. xylosus, S. saprophyticus, S. cohnii, and S. piscifermentans were predominant, and LAB such as L. fermentum, L. lactis, L. pseudomesenteroides, L. raffinolactis, L. lactis subsp cremoris could be potentially beneficial for the specific flavor of each type of adjuevan to be selected as possible starter cultures for the development of a starter culture to improve adjuevan nutritional quality.  相似文献   
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46.

Key message

The changes in the relative biomass allocation to roots in juvenile stands of fast-growing ( Leucaena leucocephala Lam., Moringa oleifera Lam., and Jatropha curcas L.) and slow-growing ( Anacardium occidentale L. and Parkia biglobosa Jacq.) afforestation species are driven mainly by ontogeny rather than resource availability. However, silvicultural management aiming at increasing availability of water and particularly nutrients enhances biomass production in all species.

Context

Understanding the patterns of biomass allocation among tree species in response to ontogeny and to variation in resource availability is key to the successful restoration of degraded land using forest plantations.

Aims

This study assessed the effects of resource availability and ontogeny on biomass accumulation and partitioning in five semi-arid afforestation species.

Methods

The aboveground and belowground biomass production of fast-growing Leucaena leucocephala Lam., Moringa oleifera Lam., and Jatropha curcas L. and slow-growing Anacardium occidentale L. and Parkia biglobosa Jacq. was monitored following the application of manure (1 kg plant?1) and/or supplemental irrigation (0.5 L per sapling daily) during the first two rainy seasons and the intervening dry season on degraded cropland in Northern Benin.

Results

Biomass accumulation in the fast-growing species was positively impacted by fertilization and irrigation during both rainy seasons. The slow-growing species responded positively to the silvicultural treatments during the dry and second rainy season. The application of fertilizer alone increased the biomass of P. biglobosa by up to 335% during the dry season. Fifteen months after planting, manure-treated L. leucocephala accumulated the most biomass (2.9 kg tree?1). The root fraction decreased with increasing tree size in all species. The comparison of root versus shoot allocation in trees of equal size indicated that the treatment-induced shifts in biomass partitioning were controlled by ontogeny, which explained 86–95% of the variation in root-shoot biomass relationships.

Conclusion

While ontogeny was the main driver of biomass partitioning, increased resource availability induced a larger production of biomass, overall leading to greater aboveground production in all species.
  相似文献   
47.
芝麻不同品种间超干种子耐藏性的差异   总被引:6,自引:0,他引:6  
对17个不同芝麻品种超干种子经高温(50℃)老化处理14d后生活力和活力指数的变化情况进行了分析。结果表明,超干芝麻种子在32℃条件下贮藏56d后,种子仍能保持较高的生活力和活力。种子耐藏性的强弱有如下趋势:褐芝麻>黑芝麻>白芝麻>黄芝麻。  相似文献   
48.
Objective: To validate the use of the LigaSure? Vessel Sealing System (LVSS) to perform thoracoscopic lung tissue biopsies in heaves‐affected horses. Study design: Prospective clinical study. Animals: Heaves‐affected horses (n=12). Methods: Lung biopsies (n=34) were collected with the LVSS (2–4 biopsies/horse) in horses with and without clinical signs of heaves. Thoracoscope (13th intercostal space [ICS]) and 2 instruments (between the 12–15th ICS) portals were used. Selected clinical and arterial blood gas variables were monitored. Postoperative pneumothorax was evaluated. Depth of thermal injury to the surrounding tissue and representativeness of the biopsies were determined. Results: Mean surgical time was 22.9±8.0 minutes. The complication rate was 5.6%, and primarily related to a focal inadequate sealing of the biopsy margin. Five horses in exacerbation required intraoperative intranasal O2. Mean PaO2 was significantly lower in heaves‐affected horses with clinical signs compared with those without clinical signs. Postoperative pneumothorax was detected radiographically after 20 of the 34 procedures. One horse with clinical signs of heaves developed a fatal tension pneumothorax 5 days postoperatively despite close radiographic monitoring. Conclusion: Thoracoscopic lung biopsy using LVSS is a rapid and effective technique to harvest peripheral lung tissues from heaves‐affected horses. Although the complication rate was tolerable, tension pneumothorax was a potential life‐threatening complication because of incomplete lung sealing. Clinical Relevance: LVSS can be used with relative safety to perform thoracoscopic lung biopsy, but close postoperative monitoring is necessary to avoid tension pneumothorax.  相似文献   
49.
An enzyme linked immunosorbent assay (ELISA) was applied to the detection of serum antibodies against infectious bovine rhinotracheitis (IBR), parainfluenza-3 (PI3), adenovirus type 3 (adeno 3) and bovine respiratory syncytial (BRS) viruses. Paired serum samples from calves vaccinated with live attenuated virus vaccines were tested. The ELISA compared favorably with the virus neutralization test for detecting serologic responses to IBR, BRS, and adeno 3 viruses or with the hemagglutination inhibition test for PI3 virus. The simplicity, sensitivity and rapidity of the ELISA test makes it a useful tool for immunological studies with respiratory viruses.  相似文献   
50.
This study examined the efficacy of bithionol as an oral treatment for Atlantic salmon Salmo salar affected by amoebic gill disease (AGD). The current commercial management strategy of AGD is a costly 3 h freshwater bath. It is labour intensive and the number of baths needed appears to be increasing; hence, there is an effort to identify alternative treatments. Efficacy was examined by feeding AGD-affected Atlantic salmon twice daily to satiation with bithionol, an antiprotozoal, at 25 mg kg− 1 feed. Three seawater (35‰, 17 °C) re-circulation systems were used each consisting of three tanks containing 32 Atlantic salmon smolts with an average (± SEM) mass of 90.4 g (± 5.2). Three feeds were examined in the trial including bithionol, plain commercial control and oil coated commercial control. Feeding commenced 2 weeks prior to exposure to Neoparamoeba spp. at 300 cells L− 1 and continued for 28 days post-exposure. Efficacy was determined by examining gross gill score and identifying percent lesioned gill filaments twice weekly for 4 weeks post-exposure. Bithionol when fed as a two-week prophylactic treatment at 25 mg kg− 1 feed delayed the onset of AGD pathology and reduced the percent lesioned gill filaments by 53% and halved the gill score from 2 to 1 when compared with both the plain and oil controls during an experimental challenge. There were no palatability problems observed with mean feed intake of bithionol over the trial duration with fish consuming higher levels of the bithionol diet compared to both the oil and plain controls. This study demonstrated that bithionol at 25 mg kg− 1 feed, when fed as a two-week prophylactic treatment for Neoparamoeba spp. exposure, delayed and reduced the intensity of AGD pathology and warrants further investigation as an alternative to the current freshwater bath treatment for AGD-affected Atlantic salmon.  相似文献   
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