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191.
Susanne Vogelgsang Franco Widmer Eveline Jenny Jürg Enkerli 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(4):477-482
Fifteen novel microsatellite markers were isolated from Fusarium graminearum. The level of polymorphism at these novel and 13 previously published microsatellite markers was analysed in 33 F. graminearum strains from Europe, North America, and Nepal. The number of alleles for each of the novel markers ranged from 4 to 20 and
gene diversity from 0.417 to 0.962. In comparison with the previously published markers, the resolution for distinguishing
among different strains was slightly increased. Twenty-seven markers were also detectable in three F. culmorum strains and one F. crookwellense strain. None of the markers was detected in three F. avenaceum and four F. poae strains, underlining the potential use of these microsatellite markers for species differentiation. 相似文献
192.
Peter Annighöfer Aitor Ameztegui Christian Ammer Philippe Balandier Norbert Bartsch Andreas Bolte Lluís Coll Catherine Collet Jörg Ewald Nico Frischbier Tsegay Gebereyesus Josephine Haase Tobias Hamm Bastian Hirschfelder Franka Huth Gerald Kändler Anja Kahl Heike Kawaletz Christian Kuehne André Lacointe Na Lin Magnus Löf Philippe Malagoli André Marquier Sandra Müller Susanne Promberger Damien Provendier Heinz Röhle Jate Sathornkich Peter Schall Michael Scherer-Lorenzen Jens Schröder Carolin Seele Johannes Weidig Christian Wirth Heino Wolf Jörg Wollmerstädt Martina Mund 《European Journal of Forest Research》2016,135(2):313-329
193.
194.
Artemis Rumbou Susanne von Bargen Rana Demiral Juliane Langer Markus Rott Risto Jalkanen 《Scandinavian Journal of Forest Research》2016,31(6):546-560
A viral epidemic associated with the Cherry leaf roll virus (CLRV) has emerged in Betula species in Fennoscandia, exhibiting quick and effective spread during the last 15 years. A population genetics approach is chosen in order to characterise the virus diversity and the sources of genetic variation aiming to investigate the epidemiology of the pathogen. In a CLRV population from Rovaniemi urban parks and a population that occurred after infecting young Betula seedlings with scions from the original Finnish trees, the genetic diversity is found to be remarkably high, mixed infections by CLRV variants from different phylogenetic groups are detected in single trees, while recombination is evidenced to occur. The estimated genetic variability is high and the CLRV haplotypes detected exhibit clear clustering and belong to different phylogenetic groups. The structure of the viral population reveals a pathogen with high evolutionary potential assumed to carry on its effective spread. 相似文献
195.
Distribution,structure and function of Nordic eelgrass (Zostera marina) ecosystems: implications for coastal management and conservation 下载免费PDF全文
Christoffer Boström Susanne Baden Anna‐Christina Bockelmann Karsten Dromph Stein Fredriksen Camilla Gustafsson Dorte Krause‐Jensen Tiia Möller Søren Laurentius Nielsen Birgit Olesen Jeanine Olsen Leif Pihl Eli Rinde 《水产资源保护:海洋与淡水生态系统》2014,24(3):410-434
- 相似文献
196.
Krogh SS Mensz SJ Nielsen ST Mortensen AG Christophersen C Fomsgaard IS 《Journal of agricultural and food chemistry》2006,54(4):1064-1074
Growing cereals (especially rye), which are incorporated into the soil to increase soil fertility or organic matter content, is a common practice in crop rotation. The additional sanitizing effect of this incorporation has often been appreciated and is said to be due to leaching of benzoxazinones and subsequent formation of benzoxazolinones. In this study wheat (Stakado) and rye (Hacada) sprouts were incorporated into soil in amounts that simulated agricultural practice. By extraction and subsequent LC-MS analysis the disappearance and appearance of benzoxazinones, benzoxazolinones, and phenoxazinones in soil were followed. In the wheat experiments 6-methoxybenzoxazolin-2-one (MBOA) was detected as the main compound. 2-Hydroxy-7-methoxy-1,4-benzoxazin-3-one (HMBOA) and 2-hydroxy-1,4-benzoxazin-3-one (HBOA) were detected as well. No phenoxazinones were detected. For the rye experiment the picture was more complex. In the first 2 days of incubation MBOA and 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) were detected as the main allelochemicals along with HBOA, HMBOA, and benzoxazolin-2-one (BOA), in decreasing order. Later in the incubation period some 2-amino-3H-phenoxazin-3-one (APO) was detected and the amount of HBOA increased considerably and decreased again. The profiling of the benzoxazinone metabolites and their derivates in soil was dynamic and time-dependent. The highest concentrations of most of the compounds were seen at day 1 after incorporation. A maximum concentration was reached at day 4 for a few of the compounds. This study is the first of its kind that shows the dynamic pattern of biologically active benzoxazinone derivates in soil after incorporation of wheat and rye sprouts. Methods for organic synthesis of HBOA and HMBOA were developed as part of the study. 相似文献
197.
Although the interferon-gamma (IFN-γ) assay for measurements of cell-mediated immune (CMI) responses to paratuberculosis PPD (johnin) has been available for close to 20 years, the assay has not yet emerged as the long desired test to identify infected animals at an early time point. Among other issues, this relates to problematic interpretation of the test results and maybe an over-expectation of what can be deducted from this kind of test given the chronic nature and slow development of infection of paratuberculosis. Over a number of years a modified IFN-γ assay with addition of recombinant bovine IL-12 to the PPDj stimulation of blood samples from the heifer group in more than 20 Danish dairy herds which also perform surveillance of MAP antibodies in milk have been performed. The results indicate that IFN-γ assay results are specific for paratuberculosis, but the IFN-γ assay result of an individual animal cannot establish whether the animal is infected or predict the future progression of disease in this animal. The IFN-γ assay should thus be used on a group of animals to test the level of exposure to paratuberculosis bacteria the animals have experienced, and thereby assist in maintaining rational in-herd management procedures and in the establishment of paratuberculosis status of a given herd. Indeed, for any diagnostic test applied in paratuberculosis, both the diagnostic target condition and the purpose of the diagnostic testing must be considered before any meaningful estimates of sensitivity or specificity can be given. 相似文献
198.
Malmuthuge N Li M Fries P Griebel PJ Guan LL 《Veterinary immunology and immunopathology》2012,146(1):18-26
The primary aim of this study was to determine regional and age-dependent expression patterns of Toll-like receptors (TLRs), peptidoglycan recognition protein 1 (PGLYRP1), and β-defensin in rumen, jejunum, ileum, cecum and colon of 3 week (n=8) and 6 month old (n=8) calves. The expression of most TLRs was significantly down-regulated throughout the gastrointestinal tract (GIT) with increasing age. TLR10 expression was significantly higher in ileum than all other gut regions, irrespective of age. TLR2 and TLR4 expression were significantly higher in the cecum and colon of 6 month old calves. Furthermore, expression of β-defensin, and PGLYRP1 was only detectable in 6 month old calves. The expression of TLRs was positively or negatively correlated with population of total bacteria and/or lactic acid bacteria depending on the GIT region. These observations indicate that innate immune responses to commensal microflora may vary significantly throughout the GIT and with age changes. 相似文献
199.
Quercus robur (L.) and Q. petraea (Matt.) Liebl. are European oak species that often grow in forest soils with high soluble manganese (Mn2+) concentrations. We tested the effects of Mn2+ at concentrations of 0.0024 mM (control), 0.24 mM (typical of acidic forest soils) and 1.2 mM (typical of forest soils under strongly reducing conditions) on the growth, tissue anatomy, foliar element concentrations, subcellular element distribution and gas exchange of solution-cultured seedlings. At the highest Mn2+ concentration, seedlings were grown with and without an elevated concentration (1.2 mM) of magnesium (Mg2+). At 0.24 mM Mn2+, foliar Mn concentrations were higher than observed in the field. Vacuoles of the leaf epidermis and mesophyll were the main sites of manganese accumulation. High nutrient solution Mn2+ concentration significantly lowered foliar iron (Fe) and Mg concentrations. Elevated Mg2+ concentration raised the foliar Mg concentrations to control values, but Fe concentrations and gas exchange remained depressed. In seedlings grown in the 1.2 mM Mn2+ treatment without elevated Mg2+ damage to the phloem of the petioles and a reduction in root mass were observed in both species. The effects on shoot and root growth were greatest in Q. petraea. Alleviation of manganese toxicity symptoms by Mg2+ in Q. petraea was less effective than in Q. robur. Our results suggest that the soil solution Mn2+ concentrations that occur in European oak forests are unlikely to affect the distribution and performance of Q. robur and Q. petraea in the field. 相似文献
200.
Possibilities for harmonizing national forest inventory data for use in forest biodiversity assessments 总被引:1,自引:0,他引:1
Winter Susanne; Chirici Gherardo; McRoberts Ronald E.; Hauk Elmar; Tomppo Erkki 《Forestry》2008,81(1):33-44
Representatives of the national forest inventories (NFIs) of27 European countries and the USA evaluated possibilities fora common approach to forest biodiversity reporting. The projectwas conducted under the auspices of COST (European Cooperationin the field of Scientific and Technical Research) Action E43,Harmonisation of National Forest Inventories in Europe:Techniques for Common Reporting. Based on the analysisof responses to an initial questionnaire regarding the mostecologically important and technically feasible variables formonitoring forest biodiversity using NFI data, 16 key variableswere selected. Responses to a second questionnaire consistingof six questions regarding assessment of the 16 key variablesrevealed that the NFIs of most responding countries alreadyassess a large proportion of these variables. Each of the 16variables is assessed in at least eight NFIs. However, the responsesregarding assessment methods and necessary field crew expertisevaried considerably. As a first example, although tree diametersat breast height (d.b.h.) are assessed by every country, thereis a wide range of minimum d.b.h. thresholds from 0 mm in Finlandto 12 cm in Cyprus and Switzerland. As a second example, eightcountries estimated that almost all inventory variables requirehighly skilled forest staff with specialized training, but mostcountries agree that a middle level of expertise is sufficient.Despite differences in current NFI methods, overall, the resultsof the study indicate positive possibilities for achieving amoderate level of European-wide harmonization. 相似文献