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991.
Inter-simple sequence repeats PCR for characterization of closely related grapevine germplasm 总被引:22,自引:0,他引:22
ISSR-PCR was carried out on 12 accessions of the grapevine (Vitis vinifera L.) variety 'Garnacha' and one accession of a related
variety. The analysis had two objectives: to determine if ISSR-PCR could detect polymorphisms within a variety unable to be
revealed previously with RAPDs, and to quantify the intralaboratory reproducibility of the assay. Two electrophoretic systems
and staining procedures were assessed. No intravarietal differences could be detected. However, the ISSR approach revealed
highly reproducible polymorphisms among the two varieties tested. The reproducibility of the banding patterns ranged from
86 to 94 per cent, being maximum when polyacrylamide gel electrophoresis and silver staining procedures were followed and
weak bands discarded.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
992.
Beltrán Fernando J. González Manuel Ribas Francisco J. Alvarez Pedro 《Water, air, and soil pollution》1998,105(3-4):685-700
Aqueous oxidation of three polynuclear aromatic hydrocarbons, fluorene, phenanthrene and acenaphthene with the combination of hydrogen peroxide and ferrous ion, Fenton reagent, has been studied. The effect of variables such as concentration of both reactants, pH and presence of bicarbonate ion and humic substances has been investigated. Products resulting from oxidation have also been identified. From experimental results and kinetic data determined the process is confirmed as an advanced oxidation involving the generation of hydroxyl radicals. Oxidation rates are even higher than those from other advanced oxidation systems involving ozone, UV radiation and hydrogen peroxide. Reactivity is in the following decreasing order: Phenanthrene > Fluorene > Acenaphthene. 相似文献
993.
Boscan P Van Hoogmoed LM Farver TB Snyder JR 《American journal of veterinary research》2006,67(6):992-997
OBJECTIVE: To evaluate the effects of morphine administration for 6 days on gastrointestinal tract function in healthy adult horses. ANIMALS: 5 horses. PROCEDURES: Horses were randomly allocated into 2 groups in a crossover study. Horses in the treatment group received morphine sulfate at a dosage of 0.5 mg/kg, IV, every 12 hours for 6 days. Horses in the control group received saline (0.9% NaCl) solution at a dosage of 10 mL, IV, every 12 hours for 6 days. Variables assessed included defecation frequency, weight of feces produced, intestinal transit time (evaluated by use of barium-filled spheres and radiographic detection in feces), fecal moisture content, borborygmus score, and signs of CNS excitement and colic. RESULTS: Administration of morphine resulted in gastrointestinal tract dysfunction for 6 hours after each injection. During those 6 hours, mean +/- SD defecation frequency decreased from 3.1 +/- 1 bowel movements in control horses to 0.9 +/- 0.5 bowel movements in treated horses, weight of feces decreased from 4.1 +/- 0.7 kg to 1.1 +/- 0.7 kg, fecal moisture content decreased from 76 +/- 2.7% to 73.5 +/- 2.9%, and borborygmus score decreased from 13.2 +/- 2.9 to 6.3 +/- 3.9. Mean gastrointestinal transit time was also increased, compared with transit times in control horses. CONCLUSIONS AND CLINICAL RELEVANCE: Morphine administered at 0.5 mg/kg twice daily decreased propulsive motility and moisture content in the gastrointestinal tract lumen. These effects may predispose treated horses to development of ileus and constipation. 相似文献
994.
Montañés F Fornari T Martín-Alvarez PJ Corzo N Olano A Ibañez E 《Journal of agricultural and food chemistry》2006,54(21):8340-8345
A selective fractionation method of carbohydrate mixtures of galactose/tagatose, using supercritical CO(2) and isopropanol as cosolvent, has been evaluated. Optimization was carried out using a central composite face design and considering as factors the extraction pressure (from 100 to 300 bar), the extraction temperature (from 60 to 100 degrees C), and the modifier flow rate (from 0.2 to 0.4 mL/min, which corresponded to a total cosolvent percentage ranging from 4 to 18% vol). The responses evaluated were the amount (milligrams) of tagatose and galactose extracted and their recoveries (percent). The statistical analysis of the results provided mathematical models for each response variable. The corresponding parameters were estimated by multiple linear regression, and high determination coefficients (>0.96) were obtained. The optimum conditions of the extraction process to get the maximum recovery of tagatose (37%) were 300 bar, 60 degrees C, and 0.4 mL/min of cosolvent. The predicted value was 24.37 mg of tagatose, whereas the experimental value was 26.34 mg, which is a 7% error from the predicted value. Cosolvent polarity effects on tagatose extraction from mixtures of galactose/tagatose were also studied using different alcohols and their mixtures with water. Although a remarkable increase of the amount of total carbohydrate extracted with polarity was found, selective extraction of tagatose decreased with increase of polarity of assayed cosolvents. To improve the recovery of extracted tagatose, additional experiments outside the experimental domain were carried out (300 bar, 80 degrees C, and 0.6 mL/min of isopropanol); recoveries >75% of tagatose with purity >90% were obtained. 相似文献
995.
Leal AT Seixas A Pohl PC Ferreira CA Logullo C Oliveira PL Farias SE Termignoni C da Silva Vaz I Masuda A 《Veterinary immunology and immunopathology》2006,114(3-4):341-345
Boophilus Yolk pro-Cathepsin (BYC) is an aspartic proteinase found in Boophilus microplus eggs that is involved in the embryogenesis and has been tested as antigen to compose an anti-tick vaccine. The vaccine potential of a recombinant BYC expressed in Escherichia coli (rBYC) was investigated. rBYC was purified and used to immunize Hereford cattle. The sera of bovines immunized with rBYC recognized the native BYC with a titer ranging from 125 to 4000. Furthermore, immunized bovines challenged with 20,000 larvae presented an overall protection of 25.24%. The partial protection obtained against B. microplus infestation with the recombinant protein immunization was similar to the already described for native BYC immunization. 相似文献
996.
This study aims to assess the long-term economic viability of deficit irrigation (DI) strategies in almond trees (cv. Marta) grown in a semiarid area (southeast Spain). A discounted cash flow analysis (DCFA) was performed to determine the profitability of the different irrigation regimes. Four irrigation treatments were evaluated over the first 6 years of an almond plantation: (1) full irrigation (FI); (2) regulated deficit irrigation (RDI) receiving 40 % ETc during kernel-filling and 100 % ETc during the remainder of the growing season; (3) mild-to-moderate sustained deficit irrigation (SDImm), irrigated at 75 % ETc (first half of the experiment) and 60 % ETc (second half of the experiment) over the entire growing season; and (4) moderate-to-severe SDI (SDIms), irrigated at 60 % ETc (first half of the experiment) and 30 % ETc (second half of the experiment) over the whole growing season. Irrigation water profit was mainly determined by the annual volume of irrigation water applied (water costs are around 50 % of variable costs). DCFA indicates that RDI and SDImm are the most economically feasible treatments, whereas FI and SDIms presented a similar degree of profitability over the 6-year period. Simulation outputs derived for the whole useful life of the investment indicate that SDImm would be the most suitable irrigation treatment to be adopted by almond farmers in the study area. We conclude that in a context of water scarcity, DI is a financially feasible alternative to FI. 相似文献
997.
Diego Toaldo Pedro Patric Pinho de Morais Jaqueline Battilana Jefferson Luís Meirelles Coimbra Altamir Frederico Guidolin 《Euphytica》2013,190(3):335-344
Crops of bean are sensible to climate changes, especially water stress. One way to minimize this instability is through genetic breeding of root system character. Thus, the objective of this study was to identify genotypes with superior root system in the first segregating generation at three depths in the soil profile and also verify the occurrence of heterosis for the root system character. Evaluations were performed using the method of Bohm (Methods studying root systems. Springer, Berlin 1979) at three different depths (0–10, 10–20 and 20–30 cm), in the experimental area of the Institute of Molecular Genetics and Breeding, at the State University of Santa Catarina UDESC Lages-SC. Twelve segregating populations and four parents (BAF 09, BAF 07, BAF 50 and IPR Uirapuru) were assessed by comparison. The favorable genotypes to the progress of generations are: two, seven and three for depths up to 20 cm and three for depths up to 30 cm. The cross between the parents BAF 07 (black group) and BAF 50 (carioca group) presented wide genetic divergence, providing significant increase in the root system revealed by the analysis of their progenies. The selection of superior genotypes in the layer of 20–30 cm was limited because most genotypes have similar and poorly distribution. Due to the strong effect of the dominance component, heterosis occurred for root distribution in early generation. This fact may interfere in the selection of autogamous species of bean related to this genetic character. 相似文献
998.
Pedro H. S. Brancalion Ricardo A. G. Viani Miguel Calmon Helena Carrascosa Ricardo R. Rodrigues 《Journal of Sustainable Forestry》2013,32(7):728-744
Large-scale ecological restoration programs across the world have begun to extensively transform degraded lands into young native ecosystems. However, more projects like these will be necessary in the coming years to fulfill the goal of restoring 150 million ha established by United Nations Convention on Biological Diversity. Here, we present and discuss the steps required for and the lessons learned from the organization of a large-scale ecological restoration program in Brazil, the Atlantic Forest Restoration Pact. These lessons are organized around 9 steps: (a) the presentation of the motivations driving the promotion of large-scale restoration, (b) the organization of the main stakeholders, (c) the definition of goals, (d) the organization of a database, (e) the indication of both available and priority areas for restoration, (f) the proposal of science-based and field-validated methods, (g) the establishment of a monitoring protocol, (h) the proposal of a communication program to unite members and interact with society, and (i) the strategies for promoting the establishment of public policies conducive to restoration. This framework may provide a template to help other initiatives to mainstream isolated restoration projects into a large and well-organized movement, which may increase the chances of successful restoration in the future. 相似文献
999.
Steben Crestani Henrique Mendonça Nunes Ribeiro Filho Marcolino Frederico Miguel Edison Xavier de Almeida Flávio Augusto Portela Santos 《Tropical animal health and production》2013,45(6):1369-1374
The inclusion of legumes in pasture reduces the need for mineral nitrogen applications and the pollution of groundwater; however, the agronomic and animal husbandry advantages with tropical legumes are still little known. The objective of this study was to quantify the effect of the use of forage peanut (Arachis pintoi cv. Amarillo) in dwarf elephant grass pastures (Pennisetum purpureum cv. BRS Kurumi) on forage intake and animal performance. The experimental treatments were dwarf elephant grass fertilized with 200 kg?N/ha, and dwarf elephant grass mixed with forage peanut without mineral fertilizers. The animals used for the experiment were 12 Charolais steers (body weight (BW)?=?288?±?5.2 kg) divided into four lots (two per treatment). Pastures were managed under intermittent stocking with an herbage allowance of 5.4 kg dry matter of green leaves/100 kg BW. Dry matter intake (mean?=?2.44 % BW), the average daily gain (mean?=?0.76 kg), and the stocking rate (mean?=?3.8 AU/ha) were similar between the studied pastures, but decreased drastically in last grazing cycle with the same herbage allowance. The presence of peanut in dwarf elephant grass pastures was enough to sustain the stocking rate, but did not allow increasing forage intake and animal performance. 相似文献
1000.
Mariasol Arias Cristiana Cazapal-Monteiro Esther Valderrábano Silvia Miguélez José Luis Rois María Eugenia López-Arellano Luis Madeira de Carvalho Pedro Mendoza de Gives Rita Sánchez-Andrade Adolfo Paz-Silva 《Journal of Equine Veterinary Science》2013
The main goal in this research was to determine the beneficial effect of incorporating biological procedures in parasite control programs for equids in zoological parks. Two trials were developed for Equus quagga, E asinus , and E africanus asinus. The first trial (September 2010 to August 2011) consisted of chemotherapy only (ivermectin plus praziquantel), and the second trial (September 2011 to September 2012) consisted of administration of chemotherapy and chlamydospores of the nematophagous fungus Arthrobotrys (Duddingtonia) flagrans. The effect of these measures was evaluated by the estimation of the reduction in the fecal egg counts (FECR). In the first trial, 100% FECR values were achieved 15 days after treatment in all the animals. The egg reappearance period (ERP) was 2-3 months for the equids, and all of them were passing strongyle eggs in the feces at 2-4 months after their deworming. In the second experiment, the FECR values were 100% in the three species. ERPs of 3 months in the European donkeys, 4 months in the Africans, and 6 months in the zebras were recorded. All the equids had positive results for the coprological flotation test 4-8 months after anthelmintic administration. This preliminary study demonstrates the incorporation of chlamydospores of nematophagous fungus, as A flagrans appears highly promising for reduction of the infective stages of the strongyles affecting captive animals, but the experimental design precludes true determination of whether the treatment is fully efficacious. 相似文献