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31.
Studies on the distribution of mammalian carnivores in fragmented landscapes have focused mainly on structural aspects such
as patch and landscape features; similarly, habitat connectivity is usually associated with landscape structure. The influence
of food resources on carnivore patch use and the important effect on habitat connectivity have been overlooked. The aim of
this study is to evaluate the relative importance of food resources on patch use patterns and to test if food availability
can overcome structural constraints on patch use. We carried out a patch-use survey of two carnivores: the beech marten (Martes foina) and the badger (Meles meles) in a sample of 39 woodland patches in a fragmented landscape in central Italy. We used the logistic model to investigate
the relative effects on carnivore distribution of patch, patch neighbourhood and landscape scale variables as well as the
relative abundance of food resources. Our results show how carnivore movements in fragmented landscapes are determined not
only by patch/landscape structure but also by the relative abundance of food resources. The important take-home message of
our research is that, within certain structural limits (e.g. within certain limits of patch isolation), by modifying the relative
amount of resources and their distribution, it is possible to increase suitability in smaller/relatively isolated patches.
Conversely, however, there are certain thresholds above which an increase in resources will not achieve high probability of
presence. Our findings have important and generalizable consequences for highly fragmented landscapes in areas where it may
not be possible to increase patch sizes and/or reduce isolation so, for instance, forest regimes that will increase resource
availability could be implemented.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
32.
Matheus D. Baldissera Carine F. Souza Keiti O. Alessio Katiane W. Krawczak Lorenzo B. Abbad Aleksandro S. da Silva Csar Bizzi Aline F. Ourique Carla C. Zeppenfeld Bernardo Baldisserotto Mauro A. Cunha 《Aquaculture Research》2020,51(10):4196-4205
The aim of this study was to determine whether feed supplementation with nanoencapsulated Ph2Se2 would improve the growth performance of silver catfish and would maintain or improve the muscle antioxidant system. Final mean weight (p = .031), weight gain (p = .014) and specific growth rates (p = .045) were significantly higher in supplemented fish than in the control group. Muscle reactive oxygen species (p = .0001) levels were significantly lower in supplemented fish than in the control group. Also, muscle hydrogen peroxide (p = .0001) and lipid peroxidation (p = .0001) levels were significantly lower in supplemented fish than in the control group. Muscle antioxidant capacity against peroxyl radical (p = .00001) levels were significantly higher in fish supplemented with both Ph2Se2 forms (free or nanocapsules) than in the control group, while muscle superoxide dismutase (p = .001) and catalase (p = .0001) activities were significantly higher in supplemented fish than in the control group. Finally, selenium (Se) deposition (p = .00001) was significantly higher in the muscle of fish supplemented with free and nanoencapsulated forms compared with the control; and deposition levels were significantly higher in fish supplemented with Ph2Se2‐loaded in nanocapsules compared with the free form. Based on this evidence, Ph2Se2‐loaded in nanocapsules improves silver catfish performance and antioxidant/oxidant status. The greater content of Se (1.22 µg/g muscle) in the muscle of fish fed with dietary Ph2Se2‐loaded nanocapsules indicates that it may be considered a nutraceutical for fish. 相似文献
33.
Lee ST Gardner DR Garrosian M Panter KE Serrequi AN Schoch TK Stegelmeier BL 《Journal of agricultural and food chemistry》2003,51(11):3228-3233
The consumption of ponderosa pine (Pinus ponderosa), lodgepole pine (Pinus contorta), common juniper (Juniperus communis), and Monterey cypress (Cupressus macrocarpa) causes abortions in pregnant cattle. Recent studies have identified isocupressic acid (1) as the primary abortificient compound in these plants. In vitro and in vivo studies using rumen and blood have shown isocupressic acid (1) is rapidly metabolized to agathic acid (3), dihydroagathic acid (4), and tetrahydroagathic acid (5). Rapid and sensitive diagnostic techniques are needed to identify poisoned animals, to study toxicokinetics, and to elucidate the mechanism of isocupressic acid-induced abortion in cattle. In this study, four competitive inhibition enzyme-linked immunosorbent assays for isocupressic acid and its sera metabolites were developed using polyclonal antibodies. One assay is specific to 1, whereas the other three assays show cross-reactivity to 3-5 in addition to 1. The assay specific to 1 had a limit of detection of 44.1 pg. The other assays which demonstrated cross-reactivity to the isocupressic acid blood metabolites also had comparably low limits of detection. One assay was used to follow the absorption and elimination profile of isocupressic acid metabolites in both cow serum and urine after oral dosage of a cow with common juniper. 相似文献
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Giovanna Jona Lasinio Alessio Pollice Livia Pappalettere Giovanni Vannacci Sabrina Sarrocco 《Plant pathology》2021,70(5):1146-1157
The Biolog phenotype microarrays (PM) system offers a simple and cheap tool to rapidly provide a high throughput of information about the phenotypes of fungal isolates in a short time. In order to improve the use of the PM system in fungal ecology studies, the present work proposes a new statistical protocol based on two approaches, that is, a functional principal components analysis to describe similarity patterns of growth curves, and a Bayesian generalized additive model (GAM) to allow inferences on specific growth features, in order to analyse nutrient fungal utilization in a model system including four causal agents of Fusarium head blight, the natural competitor Fusarium oxysporum, and the beneficial isolate Trichoderma gamsii T6085. Analysis of data collected by the Biolog PM in our biological system showed a different nutritional competitive potential of the four pathogens, as well as an intermediate behaviour of the natural competitor and of our biocontrol agent. This protocol, applicable to different fungal phenotypical studies at both isolate and community level, allows a full exploitation of data obtained by the PM system and provides important information about the nutritional pattern of a single isolate compared to those of other fungi, a key factor to be exploited in biocontrol strategies. 相似文献
40.
Angelo Nolè Alessio Collalti Federico Magnani Pierpaolo Duce Agostino Ferrara Giuseppe Mancino Serena Marras Costantino Sirca Donatella Spano Marco Borghetti 《Annals of Forest Science》2013,70(7):729-741