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1.
Reconciling food security, economic development and biodiversity conservation is a key challenge, especially in the face of the demographic transition characterizing many countries in the world. Fisheries and marine ecosystems constitute a difficult application of this bio‐economic challenge. Many experts and scientists advocate an ecosystem approach to manage marine socio‐ecosystems for their sustainability and resilience. However, the ways by which to operationalize ecosystem‐based fisheries management (EBFM) remain poorly specified. We propose a specific methodological framework—viability modelling—to do so. We show how viability modelling can be applied using four contrasted case‐studies: two small‐scale fisheries in South America and Pacific and two larger‐scale fisheries in Europe and Australia. The four fisheries are analysed using the same modelling framework, structured around a set of common methods, indicators and scenarios. The calibrated models are dynamic, multispecies and multifleet and account for various sources of uncertainty. A multicriteria evaluation is used to assess the scenarios’ outcomes over a long time horizon with different constraints based on ecological, social and economic reference points. Results show to what extent the bio‐economic and ecosystem risks associated with the adoption of status quo strategies are relatively high and challenge the implementation of EBFM. In contrast, strategies called ecoviability or co‐viability strategies, that aim at satisfying the viability constraints, reduce significantly these ecological and economic risks and promote EBFM. The gains associated with those ecoviability strategies, however, decrease with the intensity of regulations imposed on these fisheries.  相似文献   
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Evidence from DNA‐analysis is commonplace in human criminal investigations, and while it is increasingly being used in wildlife crime, to date, its application to control and enforcement activities in fisheries and aquaculture has only been sporadic. Contemporary DNA‐analysis tools are capable of addressing a broad range of compliance issues, species identification, mislabelling of fish products, determining the origin of catches and the farm of origin of aquaculture escapees. Such applications have the potential to ensure traceability along the fish product supply chain and to combat consumer fraud and Illegal, Unreported and Unregulated fishing. Nevertheless, DNA‐analysis is not yet used routinely in investigations into compliance with fisheries and aquaculture legislation. One potential reason for this is that DNA‐analysis techniques may have been regarded as too expensive. However, costs have plummeted over the past decade prompting us to objectively assess whether the costs associated with routine use of DNA‐analysis techniques for fisheries and aquaculture control and enforcement activities do constitute an impediment. Based on a number of recent fisheries and aquaculture compliance investigations that incorporated DNA‐analysis, our results indicate that the use of genetic analysis was justified and worthwhile in all cases examined. We therefore conclude that the costs associated with DNA‐analysis do not represent a barrier to the routine adoption of DNA‐analysis techniques in fisheries and aquaculture compliance investigations. Thus, control and enforcement agencies should be encouraged to use such techniques routinely.  相似文献   
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Precise and accurate patient positioning is necessary when doing stereotactic radiosurgery (SRS) to ensure adequate dosing to the tumor and sparing of normal tissues. This prospective cross‐sectional study aimed to assess feasibility of a commercially available modified frameless SRS positioning system for use in veterinary radiotherapy patients with brain tumors. Fifty‐one dogs and 12 cats were enrolled. Baseline and verification CT images were acquired. The verification CT images from 32 dogs and five cats had sufficient images for fusion to baseline CT images. A rigid box‐based fusion was performed to determine interfraction motion. Forty‐eight dogs and 11 cats were assessed for intrafraction motion by cine CT. Seventy percent of dogs and 60% of cats had interfraction 3D vector translational shifts >1 mm, with mean values of 1.9 mm in dogs, and 1.8 mm in cats. In dogs muscle wasting was weakly correlated with translational shifts. The maximum angular interfraction motion observed was 6.3° (roll), 3.5° (pitch), and 3.3° (yaw). There was no correlation between angular interfraction motion and weight, brachycephaly, or muscle wasting. Fifty‐seven percent of dogs and 50% of cats had respiration‐related intrafraction motion. Of these, 4.5% of dogs and 10% of cats had intrafraction motion >1 mm. This study demonstrates the modified Brainlab system is feasible for SRS in dogs and cats. The smaller cranial size and difference in anatomy increases setup uncertainty in some animals beyond limits usually accepted in SRS. Image‐guided positioning is recommended to achieve clinically acceptable setup accuracy (<1 mm) for SRS.  相似文献   
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The detection of hidden F-injury of forest trees by a simple colorimetric determination of peroxidase actívity . The paper describes a simple routine method for determining colorimetrically peroxidase activity (p. a.) in foliage of forest tree species, including conifers. The effect of factors such as foliage age, F Content, external F dust, necrosis etc. on p. a. is investigated. Analyses of plants exposed at different distances to F exhalates of an aluminum plant show that with decreasing distance F content and p. a. increase. P. a. thus is an indicator of air pollution effects on tree physiology even in the range where no visible symptoms of injury occur.  相似文献   
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Zusammenfassung Die Wirkung von 9 Handelspräparaten von Insektiziden (ein Carbamat, 2 Organophosphate, 4 chlorierte Hydrocarbone und 2 chlorierte Phosphorverbindungen) auf das Vorkommen vonCoccinella undecimpunctata undScymnus interruptus in einer Baumwoll-Plantage in Assiut (Ober-Ägypten) wurde geprüft Eine Fläche von 2 Feddan (= 8400 m2) wurde willkürlich in 40 Parzellen geteilt (4 Kontrollparzellen und 4 × 9 Behandlungsflächen) gemäß einem vollständig zufälligen Block-System. Die Käfer wurden in situ auf 50 Sträuchern pro Fläche knapp vor der Behandlung und am 3., 7. und 10, Tag hernach gezählt. Die Behandlung wurde viermal in Intervallen von 15 Tagen, beginnend Mitte Juni, wiederholt. Die Ergebnisse waren folgende:1. Die stärkste Anfangswirkung gegenCoccinella hatte Toxaphen/DDT/Delnav, Sevin, Lebaycid und Methyl-Parathion (70–72% Sterblichkeit in 3 Tagen nach der ersten Behandlung). Die geringste Anfangswirkung hatte Toxaphen/Dilan (um 43% Sterblichkeit in 3 Tagen).2. Die stärkste Anfangswirkung gegenScymnus hatte Sevin (um 88% Sterblichkeit in 3 Tagen) gefolgt von Toxaphen (76% Sterblichkeit). Die geringste Anfangswirkung hatte Toxaphen/Dilan (um 29% Sterblichkeit).3. Die Anfangswirkung stieg mit der Zeit nur in einigen Fällen an, z. B. bei Sevin und Lebaycid gegenCoccinella und bei Toxaphen/Dilan und Toxaphen/DDT/Delnav gegen.Scymnus.4.Scymnus scheint gegen gewisse Verbindungen empfindlicher zu sein alsCoccinella, z. B. gegen Sevin und Toxaphen, und weniger empfindlich gegen andere Verbindungen, z. B. Lebaycid.5. In den meisten Fällen stieg bei Wiederholung der Behandlung die reduzierende Wirkung bei beiden Insekten-Arten an. Solch eine verstärkte Wirkung von Sevin aufCoccinella trat bald und stetig ein.
Summary The effect of nine commercial insecticides (one carbamate, 2 phosphorous compounds, 4 chlorinated hydrocarbons and 2 combinatins of chlorinated and phosphorous compounds) on the abundance ofCoccinella undecimpunctata andScymnus interruptus on cotton was tested in an area of two Feddans (= 8400 square meters). The area was divided into 40 plots (4 controls and 4 × 9 treatments) according to a complete randomized block system. The beetles were counted in situ on 50 bushes/plot immediately before treatment and on the 3rd, 7th and 10th day thereafter. Application was repeated 4 times at 15 days intervals beginning from mid June. The results showed that:1. The strongest initial effect onCoccinella was that of toxaphene/DDT/delnav, sevin, lebaycid and methyl-parathion (70%–72% mortality in three days after the first application); the weakest initial effect was that of toxaphene/dilan (about 43% mortality in 3 days).2. The strongest initial effect onScymnus was that of sevin (about 88% mortality in 3 days), followed by toxaphene (about 76% mortality). The weakest initial effect was that of toxaphene/dilan (about 29% mortality).3. The initial effect increased by time only in a few cases, e. g. that of sevin and lebaycid onCoccinella and that of toxaphene/dilan and toxaphene/DDT/delnav onScymnus.4.Scymnus seems to be more sensitive thanCoccinella to certain compounds, e. g. sevin and toxaphene and less sensitive to other compounds e. g. lebaycid.5. In most cases repetition of application resulted in an increasing detrimental effect on both insect species. Such a cumulative effect was readily observed and rather steady in the case of sevin onCoccinella.
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The aqueous extracts of Datura fastuosa leaves and seeds were evaluated for the analgesic effect on acetic acid-induced writhing and hot plate reaction in mice. According to the results, D. fastuosa leaves and seeds extracts at oral doses of 400 and 800 mg/kg are effective as analgesic. The analgesic activity of leaf extract is reduced by naloxone but not that of seed extract.  相似文献   
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The susceptibility of some spring wheat varieties to the attack by the two wheat blossom midge species (Dipt., Cecidomyidae) The susceptibility of 20 spring wheat varieties to the attack byContarinia tritici (Kirby) andSitodiplosis mosellana (Géhin) was studied from 1971 to 1976 on small plots. Some varieties proved to be very susceptible, others were partly resistant. Meritus showed a high susceptibility to both wheat blossom midge species, while Arm showed a very low one. The resistance observed could not be explained by incoincidence. Of the varieties still being in trade, Opal should not be grown in areas of damage byS. mosellana. Kleiber and Kolibri are apt for this. Arin can be recommended to be grown in areas, where damage by both wheat blossom midges occurs.  相似文献   
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