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The objectives of the present study were to evaluate the accuracy of broad range 16S rRNA gene PCR compared to bacterial culture for the detection of synovial infection in horses. The study included 57 synovial fluid samples from horses with presumed synovial infection and a control group consisting of 31 synovial fluid samples originating from clinically normal horses and horses with aseptic synovial inflammation. All samples were analysed by 16S PCR with reverse line blot (RLB) hybridisation. Synovial fluid samples were cultured using conventional agar plate methods (APM) and/or blood culture medium (BCM). The results of the study showed a superior detection rate (89.5%) for 16S PCR with RLB. Bacterial culture had lower sensitivity, but highly acceptable detection rates (77.6%) were observed using BCM. APM had very low sensitivity (37.8%) and infection was never detected by plate isolation without positive incubation in BCM. The highest sensitivity (91.8%) for the detection of synovial infection was achieved when the results of incubation in BCM and 16S PCR were combined. For all the tests, the specificity was higher than 90%.  相似文献   
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During the last decades, European red foxes (Vulpes vulpes) have been implicated in the transmission of several viral or parasitic pathogenic agents to domestic animals and humans. In urban areas, risks of zoonoses transmission are likely to increase as a result of a higher rate of intra- and inter-species contacts. Foxes occur on 35% of the Brussels-Capital Region area and local densities reach up to 4 family groups per square kilometre. According to the directive 2003/99/ECC, a first survey for the presence in foxes of Echinococcus multilocularis and Toxocara canis was conducted in Brussels from 2001 to 2004. None of 160 foxes were found to be infected with E. multilocularis and 24 of 134 foxes were found to be infected with T. canis. Considering numbers of examined foxes, the sensitivity and the specificity of tests used for diagnosis, the 95% credibility intervals for the true prevalence of E. multilocularis and T. canis were estimated in a Bayesian framework to be 0 to 1.87% (median value of 0%) and 12.7 to 26% (median value of 18.7%), respectively. For T. canis, a significantly higher risk to be a carrier occurs in cubs and a significantly lower risk in adults.  相似文献   
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Journal of Plant Diseases and Protection - The host response of 17 cover crop cultivars to infection by single-species populations of Pratylenchus hippeastri, Pratylenchus vulnus and Pratylenchus...  相似文献   
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Marine fisheries target and catch fish both for direct human consumption (DHC) as well as for fishmeal and fish oil, and other products. We derived the fractions used for each for 1950–2010 by fishing country, and thus provide a factual foundation for discussions of the optimal use of fisheries resources. From 1950 to 2010, 27% (~20 million tonnes annually) of globally reconstructed marine fisheries landings were destined for uses other than DHC. Importantly, 90% of fish destined for uses other than DHC are food‐grade or prime food‐grade fish, while fish without a ready market for DHC make up a much smaller proportion. These findings have implications for how we are using fish to feed ourselves or, more appropriately, how we are not using fish to feed ourselves.  相似文献   
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Land allocation has been an important issue in land use planning research studies. Land allocation involves different multifunctional activities of maximizing environmental, economic and social benefits. Multi-criteria decision making (MCDM) method is the most popular tool to optimize land allocation problems by considering decision variables, conflicting objectives, and criteria. Hence, decision-makers face problems on how to optimize the land allocation while minimizing the conflicting trade-offs existing in the decision analysis. With this review study, we aim at identifying and extracting information on MCDM methods to solve land allocation problems from English language articles published between 2000 and 2019 and indexed by four scientific literature databases (Web of Science, Science Direct, Scopus, Google scholar). To this end, we applied a systematic literature review approach, i.e. the Preferred Reporting Items for Systematic Reviews and Meta-Analysis procedure (Moher et al., 2009), with a structured database search expression. 120 articles were selected of which, after careful screening of title, keywords and abstract, 69 were retained for detailed review. This review study report compiles comprehensive information by classifying the papers into application area, optimization objectives, criteria used, decision techniques, publication year and study region. In summary, we found that in the last two decades, the use of the MCDM method has increased, particularly in Europe and China. AHP (analytical hierarchal process) is frequently used for multi-attribute land allocation problems with reference to ecotourism and ecosystem management. LP (linear programming) and SA (simulating annealing) methods are predominantly used to optimize multi-objectives complex agricultural and forest land allocation problems respectively.  相似文献   
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Bobwhite quails were treated with imazalil for 8 weeks. The fungicide was given admixed in the food at 0, 100, 300, 500 and 1000 mg kg?1. Even at the highest dose tested, imazalil did not affect the liver weight or the hepatic microsomal protein content. In treated quails, no significant induction of cytochrome P-450 or NADPH-cytochrome c-reductase activity was observed. Furthermore, imazalil did not induce or inhibit 7-ethoxyresorufin or 7-ethoxycoumarin O-deethylase in quail microsomes. Only a slight but significant increase by 35% and 49% in aniline hydroxylase activity was measured for the 500- and 1000-mg kg?1 dose levels, respectively. After a drug-free period of one week, aniline hydroxylase activity returned to control values, indicating that the effect was fully reversible. It is concluded that imazalil does not induce or inhibit drug-metabolizing enzymes in the quail, even at doses which exceed by far the maximum levels currently used to dress seed under field conditions (100 mg kg?1).  相似文献   
8.
Four components of partial resistance toPhytophthora infestans were measured after inoculation in the greenhouse and in the field ofSolanum arnezii x hondelmannii, S. berthaultii, S. circaeifolium, S. leptophyes, S. microdontum, S. sparsipilum, S. sucrense andS. vernei, and four hybrid progenies ofS. microdontum withS. tuberosum. The four components were infection efficiency, lesion growth rate, generation time and sporulation capacity. The results were compared with resistance ratings derived from field experiments, and with observations made on the potato cultivars Bintje, Bildstar, Libertas and Pimpernel. Genetic variation for all components was found, while the relative importance of the components of partial resistance appeared to vary between the species. InS. microdontum, generation time, infection efficiency and lesion growth rate, and inS. tuberosum infection efficiency, lesion growth rate and sporulation capacity appeared positively associated, but in other species no such association was found. A strong hypersensitive reaction, the expression of which appeared to depend on environmental conditions, was found inS. microdontum. ForS. berthaultii, infection efficiency appeared to be the main resistance component.Abbreviations ADPC area under the disease progress curve - IE infection efficiency - LGR lesion growth rate - GT generation time - SC sporulation capacity  相似文献   
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Immunisation of calves by the infection and treatment method (I & T) has been extensively used in the eastern province of Zambia to control East Coast fever (ECF), a protozoan tick-borne disease. This paper presents the results of a field longitudinal study, which included a total of 148 Angoni calves. After immunisation against ECF, they were monitored for a full rainy season, coinciding with the main peak of activity of the vector of Theileria parva, the tick Rhipicephalus appendiculatus. Dysimmunisation (acute reaction generated by I & T immunisation), seroconversion and mortality are among the parameters recorded. The effect of maternal antibodies on these parameters was analysed and also studied in experimental conditions on two calves. Before immunisation, young calves had a higher seroprevalence than older animals (maternal antibodies) but their post-immunisation seroprevalence was lower. There was no evidence that their immunoprotection was weaker but this indicates that the post-immunisation seroconversion is probably not a reliable tool to monitor the efficacy of calf immunisation. The carrier state of cattle after immunisation was investigated in experimental conditions on three bovines whereas in the field, the infection prevalence in the ticks was estimated using the relation between the tick burden and the T. parva contacts with the calves. The ability of larval and nymphal R. appendiculatus ticks to pick-up T. parva from carriers and to transmit it to na?ve animals after moulting was assessed. It was found that both instars are able to transmit clinical and lethal ECF but that the prevalence of T. parva infection in nymphs is much lower than in adults, confirming the primary role of adults in the transmission of ECF in endemic conditions. Similar results were obtained from the field whereby the ECF peak corresponds with the peak of adult R. appendiculatus activity. The infection prevalence in the ticks was however much lower in the field than in experimental conditions indicating that an important proportion of them feed on alternative hosts. Old ticks seemed to have lost part of their infectivity.  相似文献   
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