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131.
Lisa K Karr-Lilienthal N R Merchen Christine M Grieshop Marianne J E Smeets-Peeters G C Fahey 《Archives of Animal Nutrition》2002,56(2):141-153
Little is known about the effects of gelling agents in canned dog food on nutrient digestibilities and fecal characteristics. Dogs were fed canned diets with either no gelling agent (control) or one of three gelling agents, wheat starch, a guar gum/carrageenan mixture (50:50), and a locust bean meal (LBM)/carrageenan mixture (50:50) incorporated at two levels (0.2 and 0.5% of the diet on a wet weight basis). Six dogs were fed each diet in a 6 x 7 Youden square design. Dogs fed diets containing gelling agents had higher ileal digestibilities of OM (P = 0.05), fat (P < 0.01), GE (P = 0.02), and total amino acids (P = 0.04) and lower (P < 0.01) total tract DM digestibilities when compared to dogs fed the control diet. Fecal output by dogs fed the control diet, expressed on both an as-is (73.4 g/d) and DM (45.6 g/d) basis, was lower (P < 0.01) than for dogs fed gelling agent-containing diets (mean 102.3 g/d as-is and 57.6 g/d DM). Dogs fed the control diet also had lower (P < 0.01) fecal DM percentages and higher (P = 0.02) fecal scores than dogs fed gelling agent-containing diets. 相似文献
132.
Giraud E Moulin L Vallenet D Barbe V Cytryn E Avarre JC Jaubert M Simon D Cartieaux F Prin Y Bena G Hannibal L Fardoux J Kojadinovic M Vuillet L Lajus A Cruveiller S Rouy Z Mangenot S Segurens B Dossat C Franck WL Chang WS Saunders E Bruce D Richardson P Normand P Dreyfus B Pignol D Stacey G Emerich D Verméglio A Médigue C Sadowsky M 《Science (New York, N.Y.)》2007,316(5829):1307-1312
Leguminous plants (such as peas and soybeans) and rhizobial soil bacteria are symbiotic partners that communicate through molecular signaling pathways, resulting in the formation of nodules on legume roots and occasionally stems that house nitrogen-fixing bacteria. Nodule formation has been assumed to be exclusively initiated by the binding of bacterial, host-specific lipochito-oligosaccharidic Nod factors, encoded by the nodABC genes, to kinase-like receptors of the plant. Here we show by complete genome sequencing of two symbiotic, photosynthetic, Bradyrhizobium strains, BTAi1 and ORS278, that canonical nodABC genes and typical lipochito-oligosaccharidic Nod factors are not required for symbiosis in some legumes. Mutational analyses indicated that these unique rhizobia use an alternative pathway to initiate symbioses, where a purine derivative may play a key role in triggering nodule formation. 相似文献
133.
Maria Johansson Mats Gyllin Jesper Witzell Marianne Küller 《Urban Forestry & Urban Greening》2014,13(1):28-37
Using a multilevel approach, this study investigates direct (perceptual, emotional, and physiological responses [qEEG]) and reflected (preference, attitude, and intention to accept conservation measures) appraisal of different levels of biodiversity in temperate deciduous broad-leaf forest biotopes. Thirty-five participants viewed three series of zoomed pictures from biotopes assessed according to biological criteria to be of High, Intermediate, and Low level of biodiversity. Participants’ appraisal differed between the biotopes, and partly between the conceptualisation of appraisal, but overall there was a consistency across direct and reflected levels of appraisal. The most prominent result of the analysis of qEEG was a higher brain activity in the Theta frequency for the Low biotope. The Theta frequency has amongst others been associated with on-set of sleep and in the present context probably indicating that the Low biotope was less stimulating. The Low biotope was perceived to have the lowest degree of biodiversity followed by the Intermediate and the High biotopes. The Intermediate biotope elicited the most positive emotional response, and was rated highest in preference and in importance to conserve, whereas the intention to accept conservation measures did not differ between the biotopes. Thus biodiversity related criteria presently favoured in forest conservation management schemes are not necessarily prioritised by the public. Emotional components are likely to be at stake tending to favour the conservation of biotopes of an intermediate level of biodiversity. 相似文献
134.
Griffioen K van Gemst DB Pieterse MC Jacobs F Sloet van Oldruitenborgh-Oosterbaan MM 《Veterinary journal (London, England : 1997)》2011,190(2):230-235
Culicoides spp. act as vectors for a number of viral diseases of animals including bluetongue in sheep. The aims of this study were to determine: (1) which Culicoides spp. are associated with sheep in The Netherlands; (2) the time of the day when they are most active; and (3) the effect of treatment of animals with a permethrin insecticide. Two pairs of sheep were each housed within mosquito tents of either one or two layers of netting and all trapped Culicoides spp. were identified microscopically. For the permethrin insecticide study, one of two pairs of sheep was treated with 3.6% permethrin and all animals were housed in tents of similar design. Of the 6210 midges captured, 54.1% were identified as C. chiopterus and 42.7% as C. obsoletus. C. imicola was not identified. The average insect feeding rate was 35-40% and midge activity was greatest around sunset. Permethrin treatment reduced the number of midges captured by 50% and also resulted in a decrease in the percentage of midges that had fed. The findings provide useful information on the behaviour and distribution of Culicoides spp. that will facilitate the development of appropriate control strategies to minimise the risk of insect-vector borne virus diseases such as bluetongue. 相似文献
135.
Knudsen T Kjelgaard-Hansen M Tranholm M Wiinberg B Clausen JT Hansen JJ Nichols TC Kjalke M Jensen AL Kristensen AT 《Veterinary journal (London, England : 1997)》2011,190(3):352-358
Canine coagulation factor VII (FVII) deficiency can be hereditary or acquired and may cause life threatening bleeding episodes if untreated. FVII procoagulant activity can be measured by FVII activity (FVII:C), but assays for measurement of canine specific FVII antigen (FVII:Ag) have not been available to date. In this study, a canine specific ELISA for measurement of FVII:Ag in plasma was developed and validated. The FVII:Ag ELISA correctly diagnosed homozygous and heterozygous hereditary FVII deficiency. Together with activity based assays, such as FVII:C, the FVII:Ag ELISA should be valuable in the diagnosis of hereditary canine FVII deficiency. 相似文献
136.
To improve the productivity and quality of the apple cultivar ‘Pigeon’ the influence of 5 fertigation levels (14, 42, 70, 112, 224 mg N/l) and 3 widths of herbicide strip (0.2, 0.5, 1.0 m) were investigated on growth, yield and post-harvest quality/colour development of fruit. ‘Pigeon’ apples are picked when ca. 20% of the fruit skin has turned red, the fruit are then exposed to a sunning period on the orchard floor of 2–3 weeks to enhance red colour development (80% red skin); however the internal quality deteriorates during this period. Fruit drop occurs if fruit are left on the tree to develop colour. This study focused on how to reduce the length of the post-harvest sunning period to maximise both colour development and fruit quality. It was demonstrated that 14 mg N/l resulted in a low yield, small fruit, low vegetative growth, and low N content in leaf dry matter, but good fruit colour development. Excessive N fertigation (224 mg N/l) did not produce the significantly highest yield or the largest fruit, but it did enhance vegetative growth and resulted in less fruit colouration. N fertigation influenced optimal picking date; higher N fertigation delayed the time of picking, and increased the incidence of green fruit. Fruit from the high-N treatments required more days of post-harvest sunning to obtain the comparable red skin colour than fruit from the lower N-treatments. However, when all treatments were picked at ca. 20% fruit coloration it was not possible to reduce the length of post-harvest sunning period by N-supply. Most of the post-harvest colour development occurred within the first 6–9 days following harvest; colour developed on both sides but was enhanced on the shade side of the fruit. The shade side of the fruit had a greater potential for better red colour development than the blush side of the fruit. 相似文献
137.
Lametsch R Larsen MR Essén-Gustavsson B Jensen-Waern M Lundström K Lindahl G 《Journal of agricultural and food chemistry》2011,59(21):11608-11615
Postmortem changes in pork muscle protein phosphorylation in relation to the RN(-) genotype were investigated using one-dimensional gel electrophoresis and a phosphor specific staining. The phosphorylation levels of several protein bands were found to be affected by the RN(-) genotype and to change during postmortem development. Glycogen phosphorylase, phosphofructokinase, and pyruvate kinase were found in protein bands affected by the RN(-) genotype, and the phosphorylation profile indicates that part of the increased rate and extended pH decline of the RN(-) genotype could be a consequence of phosphorylation of these key enzymes during the postmortem metabolism. The results illustrate that the protein phosphorylation level of the muscle proteins could be interpreted as a global metabolic fingerprint containing information about the activity status of the enzymes in the postmortem metabolism. 相似文献
138.
Ectodermal Wnt function as a neural crest inducer 总被引:1,自引:0,他引:1
Neural crest cells, which generate peripheral nervous system and facial skeleton, arise at the neural plate/ectodermal border via an inductive interaction between these tissues. Wnts and bone morphogenetic proteins (BMPs) play roles in neural crest induction in amphibians and zebrafish. Here, we show that, in avians, Wnt6 is localized in ectoderm and in vivo inhibition of Wnt signaling perturbs neural crest formation. Furthermore, Wnts induce neural crest from naive neural plates in vitro in a defined medium without added factors, whereas BMPs require additives. Our data suggest that Wnt molecules are necessary and sufficient to induce neural crest cells in avian embryos. 相似文献
139.
Dorothy K. Madsen Kirsten K. Sørensen Marianne H. Madsen Hanne Grethe Kirk 《American Journal of Potato Research》2006,83(4):349-355
The jasmonic acid (JA) pathway is involved in the defense mechanisms induced in plants on pathogen attack and the enzyme 12-oxophytodienoate reductase (OPR3) catalyses one of the final steps of JA synthesis. A CAPS marker, OprDM, has been developed using primers designed from the tomato (Solanum lycopersicum)OPR3 cDNA sequence. Sequencing verified that the sequence of the marker derived from potato (Solanum tuberosum) genomic DNA was 98% identical to the corresponding section of that from tomatoOPR3 cDNA. The marker was mapped and examined for association with QTLs for resistance to foliage late blight in potato. OprDM mapped close to marker GP121 on chromosome VII ofS. tuberosum. No marker sequence or clone forOPR3 has previously been mapped in potato or tomato. Results indicated the presence of two putative QTLs for foliage resistance on chromosome VII close to OprDM and CP56. The marker primers could be useful in other studies involving enzymes of the JA synthesis pathway in polymorphicSolanum populations. 相似文献
140.