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61.
Field performance of silver-birch planting-stock grown at different spacing and in containers of different volume 总被引:1,自引:0,他引:1
Silver birch seedlings were grown in two types of trays differing incell volume. For each kind of tray, three different spacings were achieved bygrowing seedlings in all, half or one quarter of the cells. The planting-stockso produced was out-planted at two forest sites and growth followed for fiveyears. Container size had a large effect on seedling morphology and on fieldperformance. Density also had a large effect on seedling morphology, but littleinfluence on performance. The tightest relationship of field performance was tothe mean dry weight of the stems of the planting stock (R2 = 0.94).Mean height and sturdiness index, defined as diameter ÷height, were not correlated with performance. Of the non-destructivemeasurements, mean root-collar diameter was the most closely correlated withperformance. 相似文献
62.
Müller Ulrich Ringhofer Andreas Brandner Reinhard Schickhofer Gerhard 《Wood Science and Technology》2015,49(6):1123-1136
Wood Science and Technology - Several studies have dealt with the problem of how to measure the shear modulus of small clear wood specimens, avoiding bias from normal compression, bending, tension... 相似文献
63.
Felipe Nogueira Soares Maria Emilia Franco Oliveira Luciana Cristina Padilha-Nakaghi Luís Guilherme de Oliveira Marcus Antônio Rossi Feliciano Felipe Brener Bezerra de Oliveira Pedro Paulo Maia Teixeira Wilter Ricardo Russiano Vicente Cristian Faturi Luiz Fernando de Souza Rodrigues 《Tropical animal health and production》2015,47(8):1465-1471
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66.
Biscogniauxia nummularia infecting beech (Fagus sylvatica) trees and sympatric plants of the sedge Carex brevicollis 下载免费PDF全文
Biscogniauxia nummularia is known for its association with beech (Fagus sylvatica), on which it occurs as a saprotroph and a pathogen causing strip cankers following water stress. This fungus has also been reported as a dominant endophytic species in plants of the sedge Carex brevicollis growing in the understory of beech forests and adjacent grasslands in Sierra de Urbasa (Navarre, Spain). In this area, stromata of B. nummularia were observed in dead and living wood of beech trees at several locations where plants of C. brevicollis also contained the fungus as an endophyte. Pure cultures obtained from stromata of B. nummularia on F. sylvatica trees were compared to endophytic isolates from symptomless C. brevicollis. Culture morphology and micromorphology as well as rDNA sequences of the internal transcribed spacer (ITS) regions were identical, suggesting that B. nummularia from beech can also live endophytically in C. brevicollis. It is unknown whether the endophytic strains of Carex might have a role as an inoculum source for the infection of beech trees, or whether they represent a dead end in the life cycle of the fungus. 相似文献
67.
Sanches Filho PJ Rios A Valcarcel M Melecchi MI Caramão EB 《Journal of agricultural and food chemistry》2007,55(3):603-607
In this paper, the use of supercritical fluid extraction (SFE) and micellar electrokinetic capillary chromatography (MEKC) is proposed for the complete analysis of volatile nitrosamines in sausages. The extraction fluid used was CO2 and variables such as density, temperature of thimbles, extraction time, modifier, fluid flow, and kind of traps were investigated. Several experiments were carried out to obtain the most favorable conditions for analysis of volatile nitrosamines in sausages. The recoveries ranged from 21 to 82% for the five nitrosamines studied. The optimal condition of extraction was 0.2 g of sample fortified with 10 mg/kg, using dynamic extraction during 20 min and with adsorbent Florisil in the trap. The solvent selected for the elution of the analytes was methanol. 相似文献
68.
A single nucleotide polymorphism (SNP) in the cytochrome b gene confers resistance to strobilurin fungicides for several fungal pathogens. Therefore, on the basis of a change at amino acid position 143 from glycine to alanine, a real-time PCR assay was established for the quantitative detection of the analogous SNP in the cytochrome b sequence of Pyrenophora teres Drechsler, which causes barley net blotch. Allelic discrimination was achieved by using allele specific primers with artificially mismatched nucleic acid bases and minor groove binding probes. Validation parameters for the lower limits of the working range, namely limits of detection (LOD) and limits of quantification (LOQ), were statistically determined by the variance of calibration data, as well as by the variance of the 100% non-strobilurin-resistant allele DNA sample (blank values). It was found that the detection was limited by the variance of blank values (five in 801 458 copies; 0.0006%), whereas the quantification was limited by the variance of calibration data (37 in 801 458 copies; 0.0046%). The real-time PCR assay was finally used to monitor strobilurin-resistant cytochrome b alleles in barley net blotch field samples, which were already classified in in vivo biotests to be fully sensitive to strobilurins. All signals for strobilurin-resistant cytochrome b alleles were below the LOD, and therefore the results are in total agreement with the phenotypes revealed by biotests. 相似文献
69.
Aparicio C Guignon B Rodríguez-Antón LM Sanz PD 《Journal of agricultural and food chemistry》2007,55(18):7394-7398
Biodiesel is an alternative to diesel oil (DO), because it is a fuel obtained from renewable resources that has lower emissions than DO. Biomass production should promote agricultural activity to obtain fuels for the transport sector. The study of the behavior of biodiesel at varying pressure and temperature is very interesting because diesel engines are mechanical systems that work with fuels submitted to high pressure. The specific volume, isothermal compressibility, and cubic expansion coefficients of refined sunflower methyl ester oil (SMEO) and unrefined sunflower methyl ester oil (URSMEO) were obtained and compared with those of DO from 0.1 to 350 MPa and 288.15 to 328.15 K. This work shows that oil refinement did not significantly modify any of the properties studied of the final biodiesel. Compared with DO, both SMEOs were about 6% denser, whereas isothermal compressibility and cubic expansion coefficients were bigger or smaller for DO depending on pressure and temperature. 相似文献
70.
López-López A Jiménez-Araujo A García-García P Garrido-Fernández A 《Journal of agricultural and food chemistry》2007,55(26):10803-10811
Table olives constitute an important part of the Mediterranean diet and the diet of many non-olive-producing countries. The aim of this work was to determine the fiber, sugar, and organic acid contents in Spanish commercial presentations of table olives and characterize them by means of a multivariate analysis. The selection of variables was carried out on the basis of a canonical analysis and their classification, according to processing styles and cultivars, through a linear discriminant analysis. Values of dietary fiber in table olives ranged from 2 to 5 g/100 g edible portion (e.p.). Some stuffing materials (almond, hot red pepper, and hazelnut) or the addition of capers produced a significant increase in the total dietary fiber in green olives. Glucose, fructose, and mannitol were usually found in the ranges of 0-55, 0-70, and 0-107 mg/100 g e.p., respectively. Succinic acid was detected only in green and directly brined olives (0-40 mg/100 g e.p.), while lactic and acetic acids were used within the ranges of 0-681 and 5-492.8 mg/100 g e.p., respectively. A multivariate analysis showed that fiber, mannitol, and succinic, lactic, and acetic acids can be used to discriminate between processing styles (95.5% correct assignations) and cultivars (61.20%). Current data can also be used in the evaluation of the dietary value of table olives. 相似文献