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121.
Have we neglected the societal importance of sand dunes? An ecosystem services perspective 总被引:1,自引:0,他引:1
- 1. Coastal sand dunes are widespread worldwide, including around the coasts of the British Isles and Europe, providing a wide range of functions some of which are recognized for their socio‐economic benefits.
- 2. In some localities, their contribution to coastal defence and to tourism and regional character have been acknowledged in local plans, but this is far from ubiquitous.
- 3. A rapid assessment was undertaken of the range of ecosystem services provided by coastal sand dune systems, using the Millennium Ecosystem Assessment ecosystem services classification augmented with habitat‐ and locally‐appropriate additions.
- 4. Sand dunes were shown to provide a wide range of provisioning, regulatory, cultural and supporting services, many of which remain substantially overlooked.
- 5. Although the importance of coastal sand dune for a diversity of characteristic and often rare organisms from a variety of taxa has been addressed, many of the broader ecosystem services that these habitats provide to society have been overlooked. This suggests that coastal sand dune systems are neglected ecosystems of significant and often under‐appreciated societal value. Copyright © 2010 John Wiley & Sons, Ltd.
122.
Claire Laguionie-Marchais A. Louise Allcock Bill J. Baker Ellie-Ann Conneely Sarah G. Dietrick Fiona Kearns Kate McKeever Ryan M. Young Connor A. Sierra Sylvia Soldatou H. Lee Woodcock Mark P. Johnson 《Marine drugs》2022,20(1)
Phylum Cnidaria has been an excellent source of natural products, with thousands of metabolites identified. Many of these have not been screened in bioassays. The aim of this study was to explore the potential of 5600 Cnidaria natural products (after excluding those known to derive from microbial symbionts), using a systematic approach based on chemical space, drug-likeness, predicted toxicity, and virtual screens. Previous drug-likeness measures: the rule-of-five, quantitative estimate of drug-likeness (QED), and relative drug likelihoods (RDL) are based on a relatively small number of molecular properties. We augmented this approach using reference drug and toxin data sets defined for 51 predicted molecular properties. Cnidaria natural products overlap with drugs and toxins in this chemical space, although a multivariate test suggests that there are some differences between the groups. In terms of the established drug-likeness measures, Cnidaria natural products have generally lower QED and RDL scores than drugs, with a higher prevalence of metabolites that exceed at least one rule-of-five threshold. An index of drug-likeness that includes predicted toxicity (ADMET-score), however, found that Cnidaria natural products were more favourable than drugs. A measure of the distance of individual Cnidaria natural products to the centre of the drug distribution in multivariate chemical space was related to RDL, ADMET-score, and the number of rule-of-five exceptions. This multivariate similarity measure was negatively correlated with the QED score for the same metabolite, suggesting that the different approaches capture different aspects of the drug-likeness of individual metabolites. The contrasting of different drug similarity measures can help summarise the range of drug potential in the Cnidaria natural product data set. The most favourable metabolites were around 210–265 Da, quite often sesquiterpenes, with a moderate degree of complexity. Virtual screening against cancer-relevant targets found wide evidence of affinities, with Glide scores <−7 in 19% of the Cnidaria natural products. 相似文献
123.
Wayne Sumpton David Mayer Ian Brown Bill Sawynok Mark McLennan Adam Butcher John Kirkwood 《Fisheries Research》2008,92(2-3):189-195
Six species of line-caught coral reef fish (Plectropomus spp., Lethrinus miniatus, Lethrinus laticaudis, Lutjanus sebae, Lutjanus malabaricus and Lutjanus erythropterus) were tagged by members of the Australian National Sportsfishing Association (ANSA) in Queensland between 1986 and 2003. Of the 14,757 fish tagged, 1607 were recaptured and we analysed these data to describe movement and determine factors likely to impact release survival. All species were classified as residents since over 80% of recaptures for each species occurred within 1 km of the release site. Few individuals (range 0.8–5%) were recaptured more than 20 km from their release point. L. sebae had a higher recapture rate (19.9%) than the other species studied (range 2.1–11.7%). Venting swimbladder gases, regardless of whether or not fish appeared to be suffering from barotrauma, significantly enhanced (P < 0.05) the survival of L. sebae and L. malabaricus but had no significant effect (P > 0.05) on L. erythropterus. The condition of fish on release, subjectively assessed by anglers, was only a significant effect on recapture rate for L. sebae where fish in “fair” condition had less than half the recapture rate of those assessed as in “excellent” or “good” condition. The recapture rate of L. sebae and L. laticaudis was significantly (P < 0.05) affected by depth with recapture rate declining in depths exceeding 30 m. Overall, the results showed that depth of capture, release condition and treatment for barotrauma influenced recapture rate for some species but these effects were not consistent across all species studied. Recommendations were made to the ANSA tagging clubs to record additional information such as injury, hooking location and hook type to enable a more comprehensive future assessment of the factors influencing release survival. 相似文献
124.
Pietro Marchese Ryan Young Enda OConnell Sam Afoullouss Bill J. Baker A. Louise Allcock Frank Barry J. Mary Murphy 《Marine drugs》2021,19(7)
Chronic diseases characterized by bone and cartilage loss are associated with a reduced ability of progenitor cells to regenerate new tissues in an inflammatory environment. A promising strategy to treat such diseases is based on tissue repair mediated by human mesenchymal stem cells (hMSCs), but therapeutic outcomes are hindered by the absence of small molecules to efficiently modulate cell behaviour. Here, we applied a high-throughput drug screening technology to bioprospect a large library of extracts from Irish deep-sea organisms to induce hMSC differentiation toward musculoskeletal lineages and reduce inflammation of activated macrophages. The library included extracts from deep-sea corals, sponges and filamentous fungi representing a novel source of compounds for the targeted bioactivity. A validated hit rate of 3.4% was recorded from the invertebrate library, with cold water sea pens (octocoral order Pennatulacea), such as Kophobelemnon sp. and Anthoptilum sp., showing the most promising results in influencing stem cell differentiation toward osteogenic and chondrogenic lineages. Extracts obtained from deep-sea fungi showed no effects on stem cell differentiation, but a 6.8% hit rate in reducing the inflammation of activated macrophages. Our results demonstrate the potential of deep-sea organisms to synthetize pro-differentiation and immunomodulatory compounds that may represent potential drug development candidates to treat chronic musculoskeletal diseases. 相似文献
125.
Berriman M Ghedin E Hertz-Fowler C Blandin G Renauld H Bartholomeu DC Lennard NJ Caler E Hamlin NE Haas B Böhme U Hannick L Aslett MA Shallom J Marcello L Hou L Wickstead B Alsmark UC Arrowsmith C Atkin RJ Barron AJ Bringaud F Brooks K Carrington M Cherevach I Chillingworth TJ Churcher C Clark LN Corton CH Cronin A Davies RM Doggett J Djikeng A Feldblyum T Field MC Fraser A Goodhead I Hance Z Harper D Harris BR Hauser H Hostetler J Ivens A Jagels K Johnson D Johnson J Jones K Kerhornou AX Koo H 《Science (New York, N.Y.)》2005,309(5733):416-422
African trypanosomes cause human sleeping sickness and livestock trypanosomiasis in sub-Saharan Africa. We present the sequence and analysis of the 11 megabase-sized chromosomes of Trypanosoma brucei. The 26-megabase genome contains 9068 predicted genes, including approximately 900 pseudogenes and approximately 1700 T. brucei-specific genes. Large subtelomeric arrays contain an archive of 806 variant surface glycoprotein (VSG) genes used by the parasite to evade the mammalian immune system. Most VSG genes are pseudogenes, which may be used to generate expressed mosaic genes by ectopic recombination. Comparisons of the cytoskeleton and endocytic trafficking systems with those of humans and other eukaryotic organisms reveal major differences. A comparison of metabolic pathways encoded by the genomes of T. brucei, T. cruzi, and Leishmania major reveals the least overall metabolic capability in T. brucei and the greatest in L. major. Horizontal transfer of genes of bacterial origin has contributed to some of the metabolic differences in these parasites, and a number of novel potential drug targets have been identified. 相似文献
126.
Potato tubers (Solanum tuberosum) from genotypes differing in chemical susceptibility to the physiological disorder blackspot bruise (TXA 763-5, Atlantic, Ranger Russet, Russet Burbank, and Lemhi Russet) were stored for eight months at 3 C. Protein extracts from each cultivar were assayed for proteinase and chorismate mutase (CM) activities. During cold storage, three of five genotypes tested increased in their ability to develop melanintype pigments responsible for blackspot. Concurrent with this were increases in either endopeptidase, aminopeptidase, or CM activities or combinations of enzyme activities specific to genotypes. These increases in enzyme activity may be responsible for the increase in levels of the melanin precursor tyrosine, associated with cold storage of potato tubers. 相似文献
127.
128.
Summary Radioactively-labeled shikimic acid (14C) was incubated with potato tuber tissue disks to determine the relative rate of tyrosine synthesis in blackspot-resistant
and susceptible cultivars. Tyrosine synthesis was 55% higher in the susceptible cultivar, Lemhi Russet, than the resistant
clone TXA 763-5. The susceptible clone also partitioned a lower percentage of14C tyrosine into soluble protein than did the resistant genotype. The percentage of labeled free tyrosine which would be available
for oxidation by polyphenyloxidase was therefore much higher in the susceptible cultivar.
Hort/LA Paper No. 90-27. Project No. 0766. Washington State University, College of Agriculture and Home Economics Research
Center, Pullman, WA 99164 相似文献
129.
Ge X d'Avignon DA Ackerman JJ Duncan B Spaur MB Sammons RD 《Pest management science》2011,67(10):1215-1221
BACKGROUND: Horseweed has been the most invasive glyphosate‐resistant (GR) weed, spreading to 16 states in the United States and found on five continents. The authors have previously reported that GR horseweed employs rapid vacuolar sequestration of glyphosate, presumably via a tonoplast transporter, substantively to reduce cytosolic glyphosate concentrations. 1 It was hypothesized that glyphosate sequestration was the herbicide resistance mechanism. If resistance is indeed endowed by glyphosate sequestration, suppression of sequestration offers the potential for controlling GR horseweed at normal herbicide field‐use rates. RESULTS: Low‐temperature 31P NMR experiments performed in vivo with GR cold‐acclimated horseweed showed markedly suppressed vacuolar accumulation of glyphosate even 3 days after glyphosate treatment. [In stark contrast, 85% of the visible glyphosate was sequestered 24 h after spraying warm‐acclimated GR horseweed.] Cold‐acclimated GR horseweed treated at normal use rates and maintained at low temperature succumbed to the lethal effects of glyphosate over a 40 day period. Treatment of GR horseweed in the field when temperatures were cooler showed the predicted positive herbicidal response. CONCLUSIONS: Low temperature markedly diminishes vacuolar sequestration of glyphosate in the GR horseweed biotype, yielding a herbicide response equivalent to that of the sensitive biotype. This supports the recent hypothesis 1 that glyphosate sequestration is the resistance mechanism employed by GR horseweed. Copyright © 2011 Society of Chemical Industry 相似文献
130.
Putnam NH Srivastava M Hellsten U Dirks B Chapman J Salamov A Terry A Shapiro H Lindquist E Kapitonov VV Jurka J Genikhovich G Grigoriev IV Lucas SM Steele RE Finnerty JR Technau U Martindale MQ Rokhsar DS 《Science (New York, N.Y.)》2007,317(5834):86-94
Sea anemones are seemingly primitive animals that, along with corals, jellyfish, and hydras, constitute the oldest eumetazoan phylum, the Cnidaria. Here, we report a comparative analysis of the draft genome of an emerging cnidarian model, the starlet sea anemone Nematostella vectensis. The sea anemone genome is complex, with a gene repertoire, exon-intron structure, and large-scale gene linkage more similar to vertebrates than to flies or nematodes, implying that the genome of the eumetazoan ancestor was similarly complex. Nearly one-fifth of the inferred genes of the ancestor are eumetazoan novelties, which are enriched for animal functions like cell signaling, adhesion, and synaptic transmission. Analysis of diverse pathways suggests that these gene "inventions" along the lineage leading to animals were likely already well integrated with preexisting eukaryotic genes in the eumetazoan progenitor. 相似文献