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991.
Paulo Henrique Mazza Rodrigues Lerner Arévalo Pinedo Paula Marques Meyer Thiago Henrique da Silva Iuli Caetano da Silva Brandão Guimarães 《Grass and Forage Science》2020,75(4):462-473
Sorghum [Sorghum bicolor (L.) Moench] is an ensilable tropical plant known as a good alternative to maize crops in regions with scarce rainfall. The objective of this trial was to obtain prediction models based on nutritional contents and end products of sorghum silage fermentation as related to the dry-matter composition of fresh plants before ensiling. Eleven different sorghum cultivars (including silage, graniferous and sweet types) were used. Twenty-five sorghum plots were harvested between 80 and 120 days of growth. Fifty plastic buckets were used as experimental microsilos and opened between 60 and 90 days of storage. Statistical modelling was used to create a prediction equation that could explain the impact of fresh sorghum composition on the chemical and nutritional composition of its silage. A complex model was detected by stepwise multiple regression to predict the difference of in vitro dry-matter digestibility (IVDMD) before and after ensiling, but a simpler model, which involved only the sum of water-soluble carbohydrate (fWSC) and hemicellulose (fHemi) concentrations in the dry matter of fresh forage, was considered to more usable. It had an acceptable coefficient of determination (0.51). The higher amount of WSC and Hemi in fresh sorghum linearly decreased the difference between IVDMD before and after the ensiling process. A WSC concentration of 125.4 g/kg DM in fresh sorghum is recommended for an ideal silage fermentation when considering pH and lactic acid levels, although ethanol levels continued to increase. 相似文献
992.
Nelson M. Gomes Lucinda J. Bessa Suradet Buttachon Paulo M. Costa Jamrearn Buaruang Tida Dethoup Artur M.S. Silva Anake Kijjoa 《Marine drugs》2014,12(2):822-839
A new meroditerpene, sartorypyrone C (5), was isolated, together with the known tryptoquivalines l (1a), H (1b), F (1c), 3′-(4-oxoquinazolin-3-yl) spiro[1H-indole-3,5′]-2,2′-dione (2) and 4(3H)-quinazolinone (3), from the culture of the marine sponge-associated fungus Neosartorya paulistensis (KUFC 7897), while reexamination of the fractions remaining from a previous study of the culture of the diseased coral-derived fungus N. laciniosa (KUFC 7896) led to isolation of a new tryptoquivaline derivative tryptoquivaline T (1d). Compounds 1a–d, 2, 3, and 5, together with aszonapyrones A (4a) and B (4b), chevalones B (6) and C (7a), sartorypyrones B (7b) and A (8), were tested for their antibacterial activity against four reference strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa), as well as the environmental multidrug-resistant isolates. Only aszonapyrone A (4a) and sartorypyrone A (8) exhibited significant antibacterial activity as well as synergism with antibiotics against the Gram-positive multidrug-resistant strains. Antibiofilm assays of aszonapyrone A (4a) and sartorypyrone A (8) showed that practically no biofilm was formed in the presence of their 2× MIC and MIC. However, the presence of a sub-inhibitory concentration of ½ MIC of 4a and 8 was found to increase the biofilm production in both reference strain and the multidrug-resistant isolates of S. aureus. 相似文献
993.
Gustavo Vitti Môro Mateus Figueiredo Santos Dyeme Antônio Vieira Bento Aurélio Mendes Aguiar Cláudio Lopes de SouzaJr. 《Euphytica》2012,185(3):419-428
Oil content and grain yield in maize are negatively correlated, and so far the development of high-oil high-yielding hybrids
has not been accomplished. Then a fully understand of the inheritance of the kernel oil content is necessary to implement
a breeding program to improve both traits simultaneously. Conventional and molecular marker analyses of the design III were
carried out from a reference population developed from two tropical inbred lines divergent for kernel oil content. The results
showed that additive variance was quite larger than the dominance variance, and the heritability coefficient was very high.
Sixteen QTL were mapped, they were not evenly distributed along the chromosomes, and accounted for 30.91% of the genetic variance.
The average level of dominance computed from both conventional and QTL analysis was partial dominance. The overall results
indicated that the additive effects were more important than the dominance effects, the latter were not unidirectional and
then heterosis could not be exploited in crosses. Most of the favorable alleles of the QTL were in the high-oil parental inbred,
which could be transferred to other inbreds via marker-assisted backcross selection. Our results coupled with reported information
indicated that the development of high-oil hybrids with acceptable yields could be accomplished by using marker-assisted selection
involving oil content, grain yield and its components. Finally, to exploit the xenia effect to increase even more the oil
content, these hybrids should be used in the Top Cross™ procedure. 相似文献
994.
Optimal defoliation management of brachiaria grass–forage peanut for balanced pasture establishment 下载免费PDF全文
O. H. Tamele O. A. A. Lopes de Sá T. F. Bernardes M. A. S. Lara D. R. Casagrande 《Grass and Forage Science》2018,73(2):522-531
A well‐established canopy is crucial for a stable mixed grass–legume forage pasture. The aim of this study was to assess a defoliation intensity that can ensure the establishment of mixed pasture of brachiaria grass (Brachiaria brizantha) intercropped with forage peanut (Arachis pintoi). The treatments comprised four canopy heights: 10, 20, 30 and 40 cm, maintained throughout the first 3 years of pasture establishment. Canopy structure, morphogenetic and structural characteristics were measured. A block design was used with four replicates, and seasons of the year were considered using repeated measurements over time. Light interception during the experimental period was 86.3%, 95.9%, 97.6%, and 99.1% for 10, 20, 30 and 40 cm of defoliation respectively (p < .001). Competition for light in taller canopies (at 30 and 40 cm) caused etiolation of forage peanut (greater internode, petiolate and stolon lengths). This response promoted its upward growth, leading to a lower stolon density compared with 10 and 20 cm. The treatment at 10 cm displayed a predominance of forage peanut (up to 0.614), potentially compromising community stability. Overall, the 20 cm canopy height showed a desired botanical composition (from 0.20 to 0.45 of legume in forage mass) and thus was considered an ideal defoliation intensity for establishment of mixed canopies of brachiaria grass and forage peanut. 相似文献
995.
Background
Biomass–density relations have been at the centre of a search for an index which describes the health of seagrass meadows. However, this search has been complicated by the intricacy of seagrass demographics and their complex biomass–density relations, a consequence mainly of their modular growth and clonality. Concomitantly, biomass–density upper boundaries have been determined for terrestrial plants and algae, reflecting their asymptotic maximum efficiencies of space occupation. Each stand’s distance to its respective biomass–density upper boundary reflects its effective efficiency in packing biomass, which has proved a reliable ecological indicator in order to discriminate between taxonomic groups, functional groups and clonal vs. non-clonal growth.Results
We gathered data from 32 studies on 10 seagrass species distributed worldwide and demonstrated that seagrasses are limited by their own boundary line, placed below the boundaries previously determined for algae and terrestrial plants. Then, we applied a new metric—dgrass: each stand’s perpendicular distance to the seagrass boundary—and used this parameter to review fundamental aspects such as clonal growth patterns, depth distribution, seasonality, interspecific competition, and the effects of light, temperature and nutrients.Conclusions
Seagrasses occupy space less efficiently than algae and terrestrial plants. Using only their biomass and density data we established a new and efficient tool to describe space occupation by seagrasses. This was used with success to evaluate their meadows as an ecological indicator for the health of coastal ecosystems.996.
Lopes R Solter PF Sisson DD Oyama MA Prosek R 《American journal of veterinary research》2006,67(6):971-977
OBJECTIVE: To identify qualitative and quantitative differences in cardiac mitochondrial protein expression in complexes I to V between healthy dogs and dogs with natural or induced dilated cardiomyopathy (DCM). SAMPLE POPULATION: Left ventricle samples were obtained from 7 healthy dogs, 7 Doberman Pinschers with naturally occurring DCM, and 7 dogs with DCM induced by rapid right ventricular pacing. PROCEDURES: Fresh and frozen mitochondrial fractions were isolated from the left ventricular free wall and analyzed by 2-dimensional electrophoresis. Protein spots that increased or decreased in density by 2-fold or greater between groups were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or quadrupole selecting, quadrupole collision cell, time-of-flight mass spectrometry. RESULTS: A total of 22 altered mitochondrial proteins were identified in complexes I to V. Ten and 12 were found in complex I and complexes II to V, respectively. Five were mitochondrial encoded, and 17 were nuclear encoded. Most altered mitochondrial proteins in tissue specimens from dogs with naturally occurring DCM were associated with complexes I and V, whereas in tissue specimens from dogs subjected to rapid ventricular pacing, complexes I and IV were more affected. In the experimentally induced form of DCM, only nuclear-encoded subunits were changed in complex I. In both disease groups, the 22-kd subunit was downregulated. CONCLUSIONS AND CLINICAL RELEVANCE: Natural and induced forms of DCM resulted in altered mitochondrial protein expression in complexes I to V. However, subcellular differences between the experimental and naturally occurring forms of DCM may exist. 相似文献
997.
This case report describes a highly pruritic, papular and crusted dermatitis affecting the dorsum of a dog and microscopically diagnosed as dermatitis induced by Straelensia cynotis. Histologically, each papule was characterized by a dilated hair follicle with marked pseudoepitheliomatous hyperplasia, perifollicular mucinosis and an abundant mononuclear infiltration by plasma and mast cells. Each dilated follicle contained a larval mite. A therapy including systemic ivermectins and oral antibiotic therapy was initiated, but the clinical response was poor. To the best of the authors' knowledge, this is the first report of straelensiosis in Portugal, and the second in Europe. 相似文献
998.
Guilherme Augusto Peres Silva Lígia Regina Lima Gouvêa Cecília Khusala Verardi Marcos Deon Vilela de Resende Erivaldo José Scaloppi Junior Paulo de Souza Gonçalves 《Euphytica》2013,189(3):343-350
Knowledge of the traits present in plant populations of a species is essential to carry out selection and breeding. The objective of the present study was to estimate the genetic parameters and correlate genetically and phenotypically the variables rubber yield, annual trunk girth increase, number of latex vessel rings and bark thickness in early measurement cycles. A total of 22 rubber tree progenies (Hevea brasiliensis) were assessed in three locations during three early measurement cycles. The bark thickness variable correlated significantly for the three increase measurements made in the locations of Jaú, Pindorama and Votuporanga. The progeny mean based joint hereditability showed mean values greater than individual plants and within progeny plants of 0.848, 0.286 and 0.242, respectively. The variables annual trunk girth increase and bark thickness are genetically correlated variables. Rubber yield is correlated genetically with bark thickness that permits simultaneous selection for the two characteristics. The early measurement cycles were efficacious for finding genetic variability among the genotypes. 相似文献
999.
Stephen M. Walker Aleksander W. Demiaszkiewicz Monika Kozak Halina Wedrychowicz Denitsa Teofanova Paulo Prodohl Gerry Brennan Ian Fairweather Elizabeth M. Hoey Alan Trudgett 《Veterinary parasitology》2013,191(1-2):161-164
We have determined the mitochondrial genotype of liver fluke present in Bison (Bison bonasus) from the herd maintained in the Bialowieza National Park in order to determine the origin of the infection. Our results demonstrated that the infrapopulations present in the bison were genetically diverse and were likely to have been derived from the population present in local cattle. From a consideration of the genetic structure of the liver fluke infrapopulations we conclude that the provision of hay at feeding stations may be implicated in the transmission of this parasite to the bison. This information may be of relevance to the successful management of the herd. 相似文献
1000.
Lychnophora ericoides Mart. (Asteraceae, Vernonieae) is a plant, endemic to Brazil, with occurrence restricted to the "cerrado" biome. Traditional medicine employs alcoholic and aqueous-alcoholic preparations of leaves from this species for the treatment of wounds, inflammation, and pain. Furthermore, leaves of L. ericoides are also widely used as flavorings for the Brazilian traditional spirit "cacha?a". A method has been developed for the extraction and HPLC-DAD analysis of the secondary metabolites of L. ericoides leaves. This analytical method was validated with 11 secondary metabolites chosen to represent the different classes and polarities of secondary metabolites occurring in L. ericoides leaves, and good responses were obtained for each validation parameter analyzed. The same HPLC analytical method was also employed for online secondary metabolite identification by HPLC-DAD-MS and HPLC-DAD-MS/MS, leading to the identification of di- C-glucosylflavones, coumaroylglucosylflavonols, flavone, flavanones, flavonols, chalcones, goyazensolide, and eremantholide-type sesquiterpene lactones and positional isomeric series of chlorogenic acids possessing caffeic and/or ferulic moieties. Among the 52 chromatographic peaks observed, 36 were fully identified and 8 were attributed to compounds belonging to series of caffeoylferuloylquinic and diferuloylquinic acids that could not be individualized from each other. 相似文献