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161.
Romildo Rocha Azevedo Junior Janaina Biral dos Santos Dilmar Baretta Alessandro Coutinho Ramos Arthur Prudêncio de Araujo Pereira Elke Jurandy Bran Nogueira Cardoso 《Journal of plant nutrition》2017,40(14):2076-2086
The goal of this study was to evaluate the effect of organic (OS) and conventional (CS) farming of Arabica coffee on chemical and microbiological soil properties and to identify which attributes correlate and/or contribute to distinguishing these two management systems. We collected soil samples on a 100 × 100 m2 grid in both, the OS and CS, in winter and summer and submitted chemical and microbiological properties to univariate and multivariate analyses (canonical discriminant analysis – CDA – and redundancy analysis – RDA). The best indicators to discriminate OS and CS were chemical and microbiological properties, as the elements calcium (Ca) and boron (B), besides microbial biomass carbon (MBC), metabolic quotient (qCO2), acid phosphatase (ACP), and alkaline phosphatase (ALP). The RDA showed that, regardless of the season, MBC and ACP correlated with nitrogen (N), sulfur (S) and organic matter (OM), whereas basal respiration (C-CO2) and ACP correlated with qCO2 and with magnesium (Mg), calcium (Ca), phosphorus (P), potassium (K) and pH. 相似文献
162.
Paulo André Vidal Bandeira José Morais Pereira Filho Aderbal Marcos de Azevêdo Silva Marcílio Fontes Cezar Olaf Andreas Bakke Uilma Laurentino Silva Jucileide Barbosa Borburema Leilson Rocha Bezerra 《Tropical animal health and production》2017,49(5):1001-1007
This study evaluated the performance and carcass characteristics of lambs fed diets with increasing levels of Mimosa tenuiflora (Willd.) hay replacing Buffel grass (Cenchrus ciliaris). Twenty-eight Santa Inês male lambs with an average body weight (BW) of 20.3 ± 1.49 kg(mean ± SD) were allocated in individual stalls and distributed in a completely random design with four treatments (0, 20, 40, and 60 g/100 g total DM M. tenuiflora hay replacing Buffel grass hay in diet) with seven replications. M. tenuiflora hay at the level of 20% dry matter (DM) total replacing Buffel grass hay increased final weight (P = 0.006), total weight gain (P < 0.001), average daily weight gain (ADWG; P < 0.001), DM intake (P < 0.001), and feed efficiency (P < 0.001). Intake of crude protein, NDFap, ADFap, ash, ether extract, total and non-fibrous carbohydrates, and total digestible nutrients presented a positive quadratic effect with M. tenuiflora hay replacing Buffel grass hay and 40 g/100 g total DM level presented greater intake. There were positive quadratic effects by M. tenuiflora hay inclusion at 20 g/100 g total DM level on slaughtering weight (P = 0.005), hot carcass weight (P = 0.002), cold carcass weight (P = 0.002), empty body weight (P = 0.001), hot carcass yield (P = 0.002), cold carcass yield (P = 0.003), and increase linear on biological yield (P = 0.003). There was no influence on cooling weight loss (P = 0.284). M. tenuiflora hay may be included in lamb diets at amounts up to 20 g/100 g total DM substitution of Buffel grass hay because increase in the nutrients intake, growth performance, and carcass characteristics. 相似文献
163.
Paul A. Umina Aston L. Arthur Stuart A. McColl Ary A. Hoffmann John M.K. Roberts 《Crop Protection》2010
Control of invertebrate pests in broad-acre agriculture largely relies on the application of broad-spectrum pesticides, however resistance problems and environmental concerns are driving a search for alternatives including more selective products. Here we explore the feasibility of using novel chemical groupings in the control of problematic pests that attack germinating pastures and grain crops in Australia. A modified laboratory bioassay is described for testing the response of several invertebrate pests to pesticides that have contact and systemic/translaminar properties. Two contact pesticides (fenitrothion and gamma-cyhalothrin) and three pesticides with strong systemic/translaminar properties (lambda-cyhalothrin, abamectin and diafenthiuron) showed promise for control of the collembolan Sminthurus viridis and four mite pests (Halotydeus destructor, Balaustium medicagoense, Penthaleus falcatus and Bryobia sp.). No single pesticide emerged as the most efficacious against all these pests, highlighting the need for correct pest identification before making control recommendations. Incorporating these new chemical options into pest control programs may help to control emerging pests and counter pesticide resistance issues. Selective pesticides in particular are likely to be compatible with integrated control programs that promote the establishment and maintenance of beneficial natural enemies. 相似文献
164.
Nieves Vidal Ana M. Vieitez M. Rosario Fernández Beatriz Cuenca Antonio Ballester 《European Journal of Forest Research》2010,129(4):635-643
Cryopreservation of selected genotypes of European chestnut and cork oak was carried out in two laboratories in a project
involving conservation of field collections. Plant material was selected on the basis of disease resistance (chestnut), growth
habit, phytosanitary performance and cork quality (cork oak). The cryopreservation technique comprised of vitrification of
shoot apices isolated from in vitro stock shoot cultures (chestnut) and somatic embryos (cork oak). Forty-three out of 46
chestnut genotypes assayed survived the freezing process, but only 63% recovered their capacity to produce new shoots. After
completion of multiplication and rooting steps, the surviving shoots produced plants that were morphologically identical to
those derived from non-supercooled material. All 51 cork oak genotypes withstood freezing and were able to produce new somatic
embryos through a process of secondary embryogenesis. Multiplication and germination of the recovered embryos enabled production
of plants that were morphologically identical to those derived from non-supercooled material. In light of the results obtained,
long-term cryopreservation of these species is feasible, thereby ensuring conservation of valuable genotypes during field
evaluation. 相似文献
165.
Blight LK Ainley DG Ackley SF Ballard G Ballerini T Brownell RL Cheng CH Chiantore M Costa D Coulter MC Dayton P Devries AL Dunbar R Earle S Eastman JT Emslie SD Evans CW Garrott RA Kim S Kooyman G Lescroël A Lizotte M Massaro M Olmastroni S Ponganis PJ Russell J Siniff DB Smith WO Stewart BS Stirling I Willis J Wilson P Woehler EJ 《Science (New York, N.Y.)》2010,330(6009):1316
166.
167.
Foston M Katahira R Gjersing E Davis MF Ragauskas AJ 《Journal of agricultural and food chemistry》2012,60(6):1419-1427
The average spatial dimensions between major biopolymers within the plant cell wall can be resolved using a solid-state NMR technique referred to as a (13)C cross-polarization (CP) SELDOM (selectively by destruction of magnetization) with a mixing time delay for spin diffusion. Selective excitation of specific aromatic lignin carbons indicates that lignin is in close proximity to hemicellulose followed by amorphous and finally crystalline cellulose. (13)C spin diffusion time constants (T(SD)) were extracted using a two-site spin diffusion theory developed for (13)C nuclei under magic angle spinning (MAS) conditions. These time constants were then used to calculate an average lower-limit spin diffusion length between chemical groups within the plant cell wall. The results on untreated (13)C enriched corn stover stem reveal that the lignin carbons are, on average, located at distances ~0.7-2.0 nm from the carbons in hemicellulose and cellulose, whereas the pretreated material had larger separations. 相似文献
168.
Romero-González R Alarcón-Flores MI Martínez Vidal JL Garrido Frenich A 《Journal of agricultural and food chemistry》2012,60(21):5324-5329
A new method has been developed and validated for the simultaneous determination of four biogenic (putrescine, cadaverine, histamine, and tyramine) and three volatile amines (trimethylamine, triethylamine, and tripropylamine) in anchovy. Separation and determination of the selected compounds were carried out by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS), using an electrospray ionization source (ESI) in positive ion mode. Chromatographic separation was carried out using an aqueous solution of formic acid (0.1%) and methanol as mobile phase in gradient mode. The method was validated, and mean recoveries were evaluated at three concentration levels (75, 150, and 250 μg/kg), ranging from 70 to 110% at the three levels assayed. Intra- and interday precision, expressed as relative standard deviation (RSD), were lower than 15% and 20%, respectively. Limits of quantitation (LOQs) were 25 μg/kg for all cases, except for that of TMA, which was set at 60 μg/kg. The developed procedure was applied to determine the target compounds in anchovy samples stored during 7 days at 4 °C, observing the increasing in the concentration of these compounds at longer storage time. 相似文献
169.
M Ugliano JB Dieval TE Siebert M Kwiatkowski O Aagaard S Vidal EJ Waters 《Journal of agricultural and food chemistry》2012,60(35):8561-8570
The evolution of different volatile sulfur compounds (VSCs) during bottle maturation of two Shiraz wines submitted to controlled oxygen exposure prior to bottling (through micro-oxygenation, MOX) and postbottling (through the closure) was investigated. H(2)S, methyl mercaptan (MeSH), and dimethyl sulfide (DMS) were found to increase during aging. Lower postbottling oxygen exposure, as obtained by different degrees of oxygen ingress through the closure, resulted in increased H(2)S and methyl mercaptan. In one wine MOX increased the concentration of H(2)S and methyl mercaptan during maturation. Dimethyl disulfide and DMS were not affected by any form of oxygen exposure. Overall, postbottling oxygen had a stronger influence than MOX on the evolution of VSCs. Data suggest that dimethyl disulfide was not a precursor to methyl mercaptan during bottle maturation. For the two wines studied, a consumption of oxygen of 5 mg/L over 12 months was the most effective oxygen exposure regimen to decrease accumulation of MeSH and H(2)S during bottle aging. 相似文献
170.
Elena Bernalte Carmen Marín Sánchez Eduardo Pinilla Gil Francisco Cereceda Balic Víctor Vidal Cortez 《Water, air, and soil pollution》2012,223(8):5143-5154
A set of 72?PM10 samples from low-polluted urban and rural locations belonging to the regional air monitoring network of Extremadura (Spain) were collected in a 1?year sampling period. Sample pre-treatment and analytical determination by gas chromatography?Cion trap mass spectrometry were optimised and validated for the analysis of the priority 16 US Environmental Protection Agency polycyclic aromatic hydrocarbons (PAHs). The influence of meteorological conditions (temperature, relative humidity and solar radiation) and other atmospheric pollutants (O3, NO2, SO2, PM10) has been covered in detail and Pearson correlation test were used for this purpose. Spatial distribution of particulate PAHs was evaluated and the comparison with other European sites was also established. Possible emission sources were identified and assigned by using molecular diagnostic criteria. 相似文献