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51.
Urban forest management needs information about the amount andkinds of recreation use, in particular about emerging recreationalactivities such as Nordic walking and winter bicycling. Between2003 and 2004, year-round use levels of recreational activitieswere investigated in a forest in Vienna using permanent time-lapsevideo recording and counts by human observers on sampling days.The amount of use, yearly, weekly and daily use patterns, aswell as the group size of the traditional activity groups werecompared with Nordic walking and winter bicycling to characterizethese activities and to better understand recreation use. Forall activity groups, the rates of participation varied significantlyacross most of the time dimensions, and the relationships betweenthe time of day and rates of participation were different forindividuals and groups. Nordic walkers displayed a temporaluse pattern similar to that of jogging with workday eveningand weekend morning use peaks, while winter bicycling was similarto bicycling activities with afternoon use peaks during snowyperiods. Nordic walking and winter bicycling activities addedto the multi-use character of the heavily used forest, but seemednot to increase the potential for user conflicts because ofthe current low participation rates and the Nordic walking group'savoidance of times of heavy use. 相似文献
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Herbert A Gerry NP McQueen MB Heid IM Pfeufer A Illig T Wichmann HE Meitinger T Hunter D Hu FB Colditz G Hinney A Hebebrand J Koberwitz K Zhu X Cooper R Ardlie K Lyon H Hirschhorn JN Laird NM Lenburg ME Lange C Christman MF 《Science (New York, N.Y.)》2006,312(5771):279-283
Obesity is a heritable trait and a risk factor for many common diseases such as type 2 diabetes, heart disease, and hypertension. We used a dense whole-genome scan of DNA samples from the Framingham Heart Study participants to identify a common genetic variant near the INSIG2 gene associated with obesity. We have replicated the finding in four separate samples composed of individuals of Western European ancestry, African Americans, and children. The obesity-predisposing genotype is present in 10% of individuals. Our study suggests that common genetic polymorphisms are important determinants of obesity. 相似文献
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Breyer J Wemheuer WM Wrede A Graham C Benestad SL Brenig B Richt JA Schulz-Schaeffer WJ 《Veterinary microbiology》2012,157(1-2):23-31
Prion diseases are diagnosed by the detection of their proteinase K-resistant prion protein fragment (PrP(Sc)). Various biochemical protocols use different detergents for the tissue preparation. We found that the resistance of PrP(Sc) against proteinase K may vary strongly with the detergent used. In our study, we investigated the influence of the most commonly used detergents on eight different TSE agents derived from different species and distinct prion disease forms. For a high throughput we used a membrane adsorption assay to detect small amounts of prion aggregates, as well as Western blotting. Tissue lysates were prepared using DOC, SLS, SDS or Triton X-100 in different concentrations and these were digested with various amounts of proteinase K. Detergents are able to enhance or diminish the detectability of PrP(Sc) after proteinase K digestion. Depending on the kind of detergent, its concentration - but also on the host species that developed the TSE and the disease form or prion type - the detectability of PrP(Sc) can be very different. The results obtained here may be helpful during the development or improvement of a PrP(Sc) detection method and they point towards a detergent effect that can be additionally used for decontamination purposes. A plausible explanation for the detergent effects described in this article could be an interaction with the lipids associated with PrP(Sc) that may stabilize the aggregates. 相似文献
56.
Arne Cierjacks Birgit Kleinschmit Maren Babinsky Fritz Kleinschroth Arvid Markert Markus Menzel Ulrike Ziechmann Theresa Schiller Markus Graf Friederike Lang 《植物养料与土壤学杂志》2010,173(5):644-653
Riparian forests are assumed to play a crucial role in the global carbon cycle. However, little data are available on C stocks of floodplains in comparison to other terrestrial ecosystems. In this study, we quantified the C stocks of aboveground biomass and soils of riparian vegetation types at 76 sampling sites in the Donau‐Auen National Park in Austria. Based on our results and a remotely sensed vegetation map, we estimated total C stocks. Carbon stocks in soils (up to 354 t ha–1 within 1 m below surface) were huge compared to other terrestrial ecosystems. As expected, soils of different vegetation types showed different texture with a higher percentage of sandy soils at the softwood sites, while loamy soils prevailed at hardwood sites. Total C stocks of vegetation types were significantly different, but reflect differences in woody plant biomass rather than in soil C stocks. Mature hardwood and cottonwood forests proved to have significantly higher total C stocks (474 and 403 t ha–1, respectively) than young reforestations (217 t ha–1) and meadows (212 t ha–1). The C pools of softwood forests (356 t ha–1) ranged between those of hardwood/cottonwood forests and of reforestations/meadows. Our study proves the relevance of floodplains as possible C sinks, which should be increasingly taken into account for river management. Furthermore, we conclude that plant‐species distribution does not indicate the conditions of sedimentation and soil C sequestration over the time span of interest for the development of soil C stocks. 相似文献
57.
Minna Nurminiemi Sten Madsen Odd Arne Rognli Âsmund Bjørnstad Rodomiro Ortiz 《Euphytica》2002,127(1):123-132
Variation in agronomic and quality characteristics was investigated in 220 Nordic spring barley cultivars across distinct
environments (6 locations during 3 years) in the Nordic Region of Europe. The objectives of this research were to determine
the importance of the genotype by environment interaction in all characteristics evaluated and to establish the relationship
among different stability statistics for grain yield. Combined analysis of variance across locations indicated that both environments
and genotype by environment interactions influenced significantly the cultivar phenotypes for all characteristics, irrespective
of their type (row number) or earliness. The first two interaction principal component axes of the additive-main-effects-and-multiplicative-interaction
(AMMI) model accounted together between 35% and 75% of the total genotype-by-environment interaction for all characteristics.
Grain yield was, on average, higher in 2-row than in 6-row cultivars, which were significantly earlier in heading and grain
maturity than the former. However, in some of the most northern locations, 6-row barley cultivars significantly outyielded
on average 2-row barley lines. The genotype by location interaction variance (σ2
GL) accounted by each genotype was significantly associated to the deviation from regression (Tai's λ) while the coefficient
of regression (β) was significantly correlated to the IPCA1 and IPCA2 of the AMMI model in 2-row, 6-row and early barley cultivars.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
58.
59.
Anne Tndervik Olav A. Aarstad Randi Aune Susan Maleki Philip D. Rye Arne Dessen Gudmund Skjk-Brk Hvard Sletta 《Marine drugs》2020,18(11)
Alginates are one of the major polysaccharide constituents of marine brown algae in commercial manufacturing. However, the content and composition of alginates differ according to the distinct parts of these macroalgae and have a direct impact on the concentration of guluronate and subsequent commercial value of the final product. The Azotobacter vinelandii mannuronan C-5 epimerases AlgE1 and AlgE4 were used to determine their potential value in tailoring the production of high guluronate low-molecular-weight alginates from two sources of high mannuronic acid alginates, the naturally occurring harvested brown algae (Ascophyllum nodosum, Durvillea potatorum, Laminaria hyperborea and Lessonia nigrescens) and a pure mannuronic acid alginate derived from fermented production of the mutant strain of Pseudomonas fluorescens NCIMB 10,525. The mannuronan C-5 epimerases used in this study increased the content of guluronate from 32% up to 81% in both the harvested seaweed and bacterial fermented alginate sources. The guluronate-rich alginate oligomers subsequently derived from these two different sources showed structural identity as determined by proton nuclear magnetic resonance (1H NMR), high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and size-exclusion chromatography with online multi-angle static laser light scattering (SEC-MALS). Functional identity was determined by minimum inhibitory concentration (MIC) assays with selected bacteria and antibiotics using the previously documented low-molecular-weight guluronate enriched alginate OligoG CF-5/20 as a comparator. The alginates produced using either source showed similar antibiotic potentiation effects to the drug candidate OligoG CF-5/20 currently in development as a mucolytic and anti-biofilm agent. These findings clearly illustrate the value of using epimerases to provide an alternative production route for novel low-molecular-weight alginates. 相似文献
60.
Ingebrigt Uglem Pål Arne Bjørn Trine Dale Sven Kerwath Finn Økland Rune Nilsen Kåre Aas Ian Fleming & Robert Scott McKinley 《Aquaculture Research》2008,39(2):158-170
Commercial farming of Atlantic cod (Gadus morhua L.) is now being developed in several countries. The ecological consequences of cod culture are poorly understood, but recent research suggests that Atlantic cod are more prone to escape from net pens than Atlantic salmon. Here, we describe the movements and the spatiotemporal distribution of farmed cod after escape relative to wild cod, both during and outside the natural spawning season. The experimental design included simulating escape incidents of farmed cod tagged with acoustic transmitters and using an array of automatic listening stations to monitor their dispersal and distribution. For comparison, local wild cod were monitored using the same array of receivers. The farmed cod dispersed rapidly after a simulated escape, they randomly distributed over large areas and their distribution overlapped with local wild cod. Moreover, escaped farmed fish were found at local cod spawning areas during the spawning season. The study also indicated that the recapture rate of escaped farmed cod was high compared with that of escaped farmed salmon. Thus, while our results showed that there is a considerable potential for ecosystem effects caused by escaped farmed cod, mitigating actions such as an efficient recapture fishery for escapees may be possible. 相似文献