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991.
Aleš Mráček Marián Lehocký Petr Smolka Ondřej Grulich Vladimír Velebný 《Fibers and Polymers》2010,11(8):1106-1110
This article describes the novel possibility of the polyester (polyethylene terephthalate) surface modification by plasma
treatment. Moreover, this modified polyester could be component for the composite material (with hyaluronic acid) used in
the wound healing. In this study, the experimental methods: FT-IR spectroscopy, the contact angle measurement, X-ray photoelectron
spectroscopy and scanning electron microscopy were used for the surface modified polyester characterisation. 相似文献
992.
Faganeli J Mohar B Kofol R Pavlica V Marinšek T Rozman A Kovač N Vuk AŠ 《Marine drugs》2010,8(9):2480-2492
The key organic constituents of marine macroaggregates (macrogels) of prevalently phytoplankton origin, periodically occurring in the northern Adriatic Sea, are proteins, lipids and especially polysaccharides. In this article, the reactivity of various macroaggregate fractions in relation to their composition in order to decode the potentially »bioavailable« fractions is summarized and discussed. The enzymatic hydrolysis of the macroaggregate matrix, using α-amylase, β-glucosidase, protease, proteinase and lipase, revealed the simultaneous degradation of polysaccharides and proteins, while lipids seem largely preserved. In the fresh surface macroaggregate samples, a pronounced degradation of the α-glycosidic bond compared to β-linkages. Degradation of the colloidal fraction proceeded faster in the higher molecular weight (MW) fractions. N-containing polysaccharides can be important constituents of the higher MW fraction while the lower MW constituents can mostly be composed of poly- and oligosaccharides. Since the polysaccharide component in the higher MW fraction is more degradable compared to N-containing polysaccharides, the higher MW fraction represents a possible path of organic nitrogen preservation. Enzymatic hydrolysis, using α-amylase and β-glucosidase, revealed the presence of α- and β-glycosidic linkages in all fractions with similar decomposition kinetics. Our results indicate that different fractions of macroaggregates are subjected to compositional selective reactivity with important implications for macroaggregate persistence in the seawater column and deposition. 相似文献
993.
J Petr E Chmelíková T Krejčová D Řehák B Novotná F Jílek 《Reproduction in domestic animals》2010,45(3):493-499
The nitric oxide donor (+)–S‐nitroso‐N‐acetylpenicillamine (SNAP) is capable of inducing parthenogenetic activation in pig oocytes matured in vitro. However, quite a long exposure to the nitric oxide donor, exceeding 10 h, is necessary for successful oocyte activation. Repeated short‐term treatment with 2 mm SNAP significantly increased the activation rates despite the fact that the overall exposure time to the nitric oxide donor did not exceed 4 h. With regard to the activation rate, 12 repeated treatments lasting 10 min each were found to be the most efficient regimen (63.3%). The continuous exposure to the nitric oxide donor for the same overall time induced parthenogenetic activation in 12.5% oocytes (2‐h continuous treatment with 2 mm SNAP). The development of parthenogenetic embryos increased after repeated short‐term treatment with SNAP. After continuous treatment with 2 mm SNAP for 10 h, only 6.7% of the oocytes cleaved, and none developed beyond the 4‐cell stage. Thirty‐minute treatment repeated four times with 2 mm SNAP induced cleavage in 37.5% of the oocytes, 18.3% developed to the morula stage, and 6.7% reached the blastocyst stage. Based on the results, it is concluded that pulsatile treatment can significantly improve parthenogenetic activation rate when compared with the continuous treatment using nitric oxide donors. 相似文献
994.
Eichmeier Aleš Kiss Tomáš Peňázová Eliška Salava Jaroslav Nečas Tomáš 《植物病害和植物保护杂志》2016,123(6):311-315
Journal of Plant Diseases and Protection - Twenty-four stone fruit trees showing typical symptoms of plum pox virus (PPV) were tested for PPV using ELISA, RT-PCR, real-time RT-PCR and RT-LAMP. The... 相似文献
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998.
Tomáš Policar Miroslav Blecha Jiří Křišťan Jan Mráz Josef Velíšek Alžběta Stará Vlastimil Stejskal Oleksandr Malinovskyi Petr Svačina Azin Mohagheghi Samarin 《Aquaculture International》2016,24(6):1607-1626
Production efficiency, frequency of fin erosion, skeletal and gill covers deformities, proximal composition of fish body with special emphasis on fatty acid contents in liver and muscle, oxidative stress and antioxidant response in gill, liver, muscle and intestine were analyzed and compared in exclusively RAS- and POND-cultured juveniles and juveniles produced with the combination of POND and RAS aquaculture in pikeperch (Sander lucioperca L.) with final body weight between 8.5 and 9.5 g. Higher production efficiency, lower fin erosion, no morphological deformities, higher level of essential fatty acids and lower oxidative stress were found in POND–RAS- and POND-cultured juveniles compared to exclusively RAS-produced pikeperch. This study showed that intensive pikeperch juvenile production still needs next technological innovations. On the other hand, the combination of POND–RAS aquaculture has provided a good potential to be an alternative production system producing high-quality juveniles for intensive or pond ongrowing culture mainly in countries with large pond area. 相似文献
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1000.
Alisa Šehić Jelena Vasiljević Igor Jordanov Andrej Demšar Jožef Medved Ivan Jerman Marija Čolović Fiona Hewitt T. Richard Hull Barbara Simončič 《Fibers and Polymers》2018,19(6):1194-1206
This research investigated the influence of two flame retardant (FR) mixtures consisting melamine cyanurate (MeCy) and aluminum diethylphosphinate (AlPi), and MeCy and sodium aluminosilicate (SASi) at different weight ratios, on the flammability, thermal behavior and mechanical properties of polyamide 6 (PA6) composite yarns produced by meltspinning. The morphological and chemical properties of PA6/FR filaments were investigated by scanning electron microscopy and Fourier-transform infrared spectroscopy, flame retardancy by vertical burning test UL-94, thermal behavior by thermogravimetric and differential scanning calorimetric analyses, and mechanical properties by tensile tests. The results indicate that within the UL 94 V2 rating, the composite yarns differed significantly from each other in their burning and dripping behavior. The incorporation of both mixtures, MeCy+AlPi and MeCy+SASi, into the PA6/FR yarns significantly decreased the afterflame time relative to pristine PA6, confirming a lower production of flammable volatiles. This phenomenon was attributed mainly to MeCy, which caused an immediate extinguishment of the flame after the withdrawal of the igniting flame. Compared to one component MeCy, the incorporation of the MeCy+SASi mixture enhanced the thermooxidative stability of the PA6/FR yarns because of their additive effect at higher concentrations. In contrast, an antagonistic effect was obtained for the MeCy+AlPi mixture, irrespective of the concentration. Since the incorporation of MeCy+SASi did not drastically reduce the tensile properties of filaments, this mixture enables the production of the PA6/MeCy+SASi composite yarns with the enhanced flame retardancy and thermo-oxidative stability. 相似文献