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631.
Eucalyptus plantations can be affected by species of defoliating caterpillars. The integrated management of this group primarily involves a monitoring system, natural enemies, and biological products. Alternative control methods, including the use of conventional light traps, have not been adopted, mostly because of their low efficiency. Therefore, a more efficient light trap model was developed. The new model allowed the capture of 3.6 times as many insects as the conventional model, with a 261% gain in control efficiency. The use of this new model represents another integrated management alternative for lepidopteran pests of eucalyptus plantations and other cultured plants.  相似文献   
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The culturing of Leptospira strains from bovine clinical samples is challenging and has resulted in some gaps in securing an epidemiological understanding. Strains related to chronic reproductive leptospirosis in cattle belong to the Sejroe serogroup – not only Hardjoprajitno and Hardjobovis but also Guaricura genotypes. This study analyses the growth of Leptospira strains from serogroup Sejroe in different culture media, with the aim of suggesting better culturing approaches. To meet this objective, two culture media were applied: EMJH and T80/40/LH. In addition, three different cocktails of selective agents were chosen. The combinations of medium and selective additives resulted in 10 different tested formulae. The poor performance of Hardjobovis in EMJH indicated that its growth may represent a possible bias when culturing these strains from bovine samples. The most efficient medium for culturing Hardjobovis was T80/40/LH, while T80/40/LH medium + STAFF combination proved to be the best choice for growth, being recommended for obtaining a higher number of these strains from bovines.  相似文献   
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The interaction between hunting interests and legally protected predators is often a contentious conservation problem, requiring detailed understanding of predator responses to game management. This issue was addressed in southern Portugal in a treatment-control natural experiment, whereby the abundances of small game, corvids, birds of prey and carnivores were compared in 12 game estates (>500 ha) and 12 matching areas with similar sizes and land uses but no game management. European rabbits (Oryctolagus cuniculus), Iberian hares (Lepus granatensis) and, less so, red-legged partridges (Alectoris rufa) were far more numerous in game estates than elsewhere. Among legally controlled species, there were less Eurasian jays (Garrulus glandarius) but more red foxes (Vulpes vulpes) in game estates, though the latter were primary targets of predator culling. Fox abundance within game estates varied inversely with an index of management intensity (density of small game feeding sites) and increased along with hare abundance. As for protected species, only common kestrels (Falco tinnunculus) and genets (Genetta genetta) were fewer in game estates. The abundance of raptors within game estates varied inversely with gamekeeper density, whereas that of common buzzards (Buteo buteo) increased along with rabbit abundance. Overall, there was little evidence that game management reduced local predator abundances, except in the most intensively managed estates. Game estates provided concentrations of prey that was scarce elsewhere, which may have favoured increased abundances of some predators. Further investigations are needed to find out whether high prey densities may attract predators to game estates with increased mortality risk, which may thus become population sinks for protected species.  相似文献   
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The use of active ingredients in wound management have evolved alongside the pharmaceutical agents and dressings used to deliver them. However, the development of gauzes, dressings with specific properties, still remains a challenge for several medical applications. A new methodology for the controlled release of active components for the healing of burn wounds is proposed herein. Cotton and non‐woven bandages have been cationised to promote the attachment of protein microspheres. The active agents, piroxicam and vegetable oil, were entrapped into the microspheres using ultrasound energy. Active agents were released from the microspheres by a change in pH. Wound healing was assessed through the use of standardised burn wounds induced by a cautery in human full‐thickness skin equivalents (EpidermFT). The best re‐epithelialisation and fastest wound closure was observed in wounds treated with proteinaceous microspheres attached to gauzes, after six days of healing, in comparison with commercial collagen dressing and other controls. Furthermore, the ability of these materials to reduce the inflammation process, together with healing improvement, makes these biomaterials suitable for wound‐dressing applications.  相似文献   
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Anaerobic degradation of long-chain fatty acids (LCFA) involves syntrophic bacteria and methanogens, but facultative anaerobic bacteria (FAB) might have a relevant role as well. Here we investigated oleate degradation by a syntrophic synthetic co-culture of Syntrophomonas zehnderi (Sz) and Methanobacterium formicicum (Mf) and FAB (two oleate-degrading Pseudomonas spp. I1 + I2). Sz + Mf were first cultivated in a continuous bioreactor under strict anaerobic conditions. Thereafter, I1 + I2 were inoculated and microaerophilic conditions were provided. Methane and acetate were the main degradation products by Sz + Mf in anaerobiosis and by Sz + Mf + I1 + I2 in microaerophilic conditions. However, acetate production from oleate was higher in microaerophilic conditions (5% O2) with the four microorganisms together (0.41 ± 0.07 mmol day−1) than in anaerobiosis with Sz + Mf (0.23 ± 0.05 mmol day−1). Oleate degradation in batch assays was faster by Sz + Mf + I1 + I2 (under microaerophilic conditions) than by Sz + Mf alone (under strict anaerobic conditions). I1 + I2 were able to grow with oleate and with intermediates of oleate degradation (hydrogen, acetate and formate). This work highlights the importance of FAB, particularly Pseudomonas sp., in anaerobic reactors treating oleate-based wastewater, because they accelerate oleate conversion to methane, by protecting strict anaerobes from oxygen toxicity and also by acting as alternative hydrogen/formate and acetate scavengers for LCFA-degrading anaerobes.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - The use of silicon (Si) has been shown to be a good alternative to improve the growth and content of photosynthetic pigments of plants propagated in...  相似文献   
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