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1.
The current study was initiated to evaluate the efficacy of physical methods (hot water, aerated steam, electron treatment) and agents of natural origin (resistance inducers, plant derived products, micro-organisms) as seed treatments of carrots for control of Alternaria dauci and A. radicina. Control of both Alternaria species by seed treatment with the resistance inducers was generally poor. Results were also not satisfactory with most of the formulated commercial micro-organism preparations. Based on the average of five field trials, one of these, BA 2552 (Pseudomonas chlororaphis), provided a low but significant increase in plant stand. Among the experimental micro-organisms, the best results were obtained with Pseudomonas sp. strain MF 416 and Clonostachys rosea strain IK726. A similar level of efficacy was provided by seed treatment with an emulsion (1%) of thyme oil in water. Good and consistent control was generally achieved with the physical methods aerated steam, hot water and electron treatment. Aerated steam treatment was, apart from the thiram-containing chemical standard, the best single treatment, and its performance may at least partially be due to extensive pre-testing, resulting in dosages optimally adapted to the respective seed lot. In some of the experiments the effect of the hot water treatment, which was tested at a fixed, not specifically adapted dosage, was significantly improved when combined with a Pseudomonas sp. MF 416 or C. rosea IK726 treatment. The results are discussed in relation to the outcome of experiments in which the same seed treatment methods and agents were tested in other seed-borne vegetable pathosystems.  相似文献   
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In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis (crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative, as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
Sabine AugustinEmail:
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Amaranthus leaf mottle virus (AmLMV) was classified as a member of the genus Potyvirus on the basis of its particle morphology, serology, and biological properties (Casetta et al., 1986). Based on these properties, an Amaranthus viridis-infecting virus isolated in Spain, causing mottle and leaf blistering as well as reduced growth has been identified as AmLMV. The 3′ terminal genomic region of this and a reference isolate from Italy has been sequenced and reveals a 95% nucleotide identity between the two isolates. The sequenced part comprises the coat protein with 281 amino acids and 315 nucleotides of the 3′ untranslated region (UTR) preceding a polyadenylated tail. Pairwise comparisons and phylogenetic analysis of the nucleotide and deduced amino acid sequences of the CP and 3′ UTR of the cloned cDNAs with those of other potyviruses shows that AmLMV is a distinct potyvirus closely related to Potato virus Y.  相似文献   
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The development of a new and improved vaccine against tuberculosis has in the last 10 years been accelerated tremendously from the completed Mycobacterium tuberculosis genome and the progress in molecular biology. This has resulted in the identification of a large number of antigens with potential in tuberculosis vaccines. The next phase of this work has now started--putting the most relevant molecules back together as fusion molecules and cocktails. This requires carefully monitoring of aspects as immunodominance, recognition in different populations as well as the influence of different adjuvants and delivery systems. The most advanced of these vaccines such as the fusion between ESAT6 and Ag85B have been evaluated in a range of animal models including non-human primates and are now entering into clinical trials. For these vaccines to be successfully implemented in future vaccination programmes it is necessary to understand the immunological background for the failure of BCG and optimize the vaccines for their ability to boost the immuno-response primed by BCG.  相似文献   
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The present study investigated the effects of sequential collection of milt, time of post-mortem storage and anesthesia on rainbow trout (Oncorhynchus mykiss) sperm motility parameters (using computer-assisted sperm analysis – CASA) as well as seminal plasma osmolality and sperm concentration. The post-mortem storage and time of anesthesia altered motility characteristics of rainbow trout sperm to different extents. The moderate impact of time of anesthesia was manifested in a shortened duration of sperm motility after 10 min exposure of fish to anesthetic. The prolonged post-mortem storage (≥40–60 min), in addition to lowering sperm motility duration, also significantly influenced sperm motility parameters, such as sperm velocities, percentage of motile sperm and sperm trajectory parameters. These results clearly demonstrate that when milt from sacrificed fish is used for sperm motility studies, the time of post-mortem storage significantly alters sperm motility characteristics. Since sperm motility rate and swimming velocity could predict fertilizing ability, detrimental effects of prolonged post-mortem storage may lead to reduced fertilization success. Sperm concentration and seminal plasma osmolality were lower in the first fractions and increased with successive collections of milt. It suggests the presence of urine contamination of the first milt fractions which were collected by stripping. Therefore, testing of sperm concentration and/or seminal plasma osmolality should be mandatory while handling stored milt.  相似文献   
7.
Summary Improvement of durum wheat at the International Maize and Wheat Improvement Center (CIMMYT) was achieved by exploiting the variability of the tetraploid species in large numbers of combinations, and multi-location testing of germplasm on a world wide base. High yielding, widely adapted durums with short straw, good fertility, and adequate earliness were selected for distribution to major durum growing countries. Present attempts to improve durum wheat are directed at adjusting agronomic traits such as leaf angle and straw strength, and increasing spike fertility and spike size, thereby reaching higher grain numbers per unit area and higher yield potential. Diversification of the developmental pattern and incorporation of drought tolerance aim at further widening adaptation.  相似文献   
8.
Apples represent a major dietary source of antioxidative polyphenols. Their metabolic conversion by the gut microflora might generate products that protect the intestine against oxidative damage. We studied the antioxidant effectiveness of supernatants of fermented apple juice extracts (F-AEs, 6 and 24 h fermentation) and of selected phenolic degradation products, identified by HPLC-DAD-ESI-MS. Cell free antioxidant capacity of unfermented apple juice extracts (AEs) was decreased after fermentation by 30-50%. In the human colon carcinoma cell line Caco-2, F-AEs (containing <0.5% of original AE-phenolics) decreased the reactive oxygen species (ROS) level more efficiently than the F-blank (fermented without AE) but were less effective than the respective AEs. Similarly, antioxidant effectiveness of individual degradation products was lower compared to respective AE constituents. Glutathione level was slightly increased and oxidative DNA damage slightly decreased by fermented AE03, rich in quercetin glycosides. In conclusion, F-AEs/degradation products exhibit antioxidant activity in colon cells but to a lesser extent than the respective unfermented AEs/constituents.  相似文献   
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We wish to report the identification, from a flock of commercially-traded goats, of nematode worms that we have been unable to kill using the anthelmintic groups currently registered for use in sheep in New Zealand.  相似文献   
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