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951.
The mechanical and thermal behavior of compression molded jute/polypropylene (PP) composites were studied by evaluating tensile strength (TS), bending strength (BS), tensile modulus (TM), bending modulus (BM), impact strength (IS), thermogravimetric (TG/DTG) and differential thermal analysis (DTA). A chemical modification was made to jute fabrics using N,N-Dimethylaniline (DMA) in order to improve the interfacial adhesion between the fabrics and matrix. It was found that jute fabrics on treatment with N,N-Dimethylaniline (DMA) significantly improved the mechanical properties of the composites. Thermal analytical data of PP, both treated and untreated jute fabrics as well as composites revealed that DMA treatment increased the thermal stability of the fabrics and composite. DMA treatment also reduced the hydrophilic nature of the composite. DMA treated jute composite was found less degradable than control composite under water, soil and simulated weathering conditions. 相似文献
952.
M?rten Strand Marcus Carlsson Hanna Uvell Koushikul Islam Karin Edlund Inger Cullman Bj?rn Altermark Ya-Fang Mei Mikael Elofsson Nils-Peder Willassen G?ran Wadell Fredrik Almqvist 《Marine drugs》2014,12(2):799-821
Adenovirus infections in immunocompromised patients are associated with high mortality rates. Currently, there are no effective anti-adenoviral therapies available. It is well known that actinobacteria can produce secondary metabolites that are attractive in drug discovery due to their structural diversity and their evolved interaction with biomolecules. Here, we have established an extract library derived from actinobacteria isolated from Vestfjorden, Norway, and performed a screening campaign to discover anti-adenoviral compounds. One extract with anti-adenoviral activity was found to contain a diastereomeric 1:1 mixture of the butenolide secondary alcohols 1a and 1b. By further cultivation and analysis, we could isolate 1a and 1b in different diastereomeric ratio. In addition, three more anti-adenoviral butenolides 2, 3 and 4 with differences in their side-chains were isolated. In this study, the anti-adenoviral activity of these compounds was characterized and substantial differences in the cytotoxic potential between the butenolide analogs were observed. The most potent butenolide analog 3 displayed an EC50 value of 91 μM and no prominent cytotoxicity at 2 mM. Furthermore, we propose a biosynthetic pathway for these compounds based on their relative time of appearance and structure. 相似文献
953.
Gram-negative marine bacteria can thrive in harsh oceanic conditions, partly because of the structural diversity of the cell wall and its components, particularly lipopolysaccharide (LPS). LPS is composed of three main parts, an O-antigen, lipid A, and a core region, all of which display immense structural variations among different bacterial species. These components not only provide cell integrity but also elicit an immune response in the host, which ranges from other marine organisms to humans. Toll-like receptor 4 and its homologs are the dedicated receptors that detect LPS and trigger the immune system to respond, often causing a wide variety of inflammatory diseases and even death. This review describes the structural organization of selected LPSes and their association with economically important diseases in marine organisms. In addition, the potential therapeutic use of LPS as an immune adjuvant in different diseases is highlighted. 相似文献
954.
Ishfaq Muhammad Akbar Nadeem Zulfiqar Usman Ali Nauman Shah Fahimuddin Anjum Shakeel Ahmad Farooq Muhammad 《Paddy and Water Environment》2022,20(1):37-50
Paddy and Water Environment - Globally, increasing water scarcity and higher production costs are the challenges in the cultivation of conventional transplanted rice (TPR). Under such conditions,... 相似文献
955.
Faqir Muhammad M.Akram Tariq & Yusuf Ali ) Department of Horticulture University of Agricultute Faisalabad) Citrus Research Station Sahiwal) Department of Horticulture University College of Agriculture Rawalkot 《浙江大学学报(农业与生命科学版)》1990,(2)
Research studies on the corelation of growth and yield as affected by different levels of Nitrogen in Feutrell's Early revealed that the yield is directly responsible for growth. Increasing nitrogen level increase the growth and yield of plants upto a certain limit but when this limit is cro ssed, the growth of tree may increase in terms of girth and height but the spread and yield of the tree is decreased. This indicates the effect of nitrogen in relation of growth and yield. 相似文献
956.
Apparent variations in nitrogen runoff and its uptake in paddy rice under straw incorporation
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Muhammad Amjad BASHIR ZHAI Li-mei WANG Hong-yuan LIU Jian Qurat-Ul-Ain RAZA GENG Yu-cong Abdur REHIM LIU Hong-bin 《农业科学学报》2022,21(11):3356-3367
Straw incorporation is a widespread practice to promote agricultural sustainability. However, the potential effects of straw incorporation with the prolonged time on nitrogen (N) runoff loss from paddy fields are not well studied. The current study addresses the knowledge gap by assessing the effects of straw incorporation on the processes influencing N runoff patterns and its impacts on crop yield, N uptake, total N (TN), and soil organic matter (SOM). We conducted field experiments with rice (Oryzasativa L.)–wheat (Triticumaestivum L.) rotation, rice–tobacco (Nicotianatabacum L.) rotation, and double-rice cropping in subtropical China from 2008 to 2012. Each rotation had three N treatments: zero N fertilization (CK), chemical N fertilization (CF), and chemical N fertilization combined with straw incorporation (CFS). The treatment effects were assessed on TN runoff loss, crop yield, N uptake, soil TN stock, and SOM. Results showed that TN runoff was reduced by substituting part of the chemical N fertilizer with straw N in the double rice rotation, while crop N uptake was significantly (P<0.05) decreased due to the lower bioavailability of straw N. In contrast, in both rice–wheat and rice–tobacco rotations, TN runoff in CFS was increased by 0.9–20.2% in the short term when straw N was applied in addition to chemical N, compared to CF. However, TN runoff was reduced by 2.3–19.3% after three years of straw incorporation, suggesting the long-term benefits of straw incorporation on TN loss reduction. Meanwhile, crop N uptake was increased by 0.8–37.3% in the CFS of both rotations. This study demonstrates the challenges in reducing N runoff loss while improving soil fertility by straw incorporation over the short term but highlights the potential of long-term straw incorporation to reduce N loss and improve soil productivity. 相似文献
957.
Habib-ur-Rahman Muhammad Raza Ahsan Ahrends Hella Ellen Hüging Hubert Gaiser Thomas 《Precision Agriculture》2022,23(3):912-938
Precision Agriculture - Crop cultivation provides ecosystem services on increasingly large fields. However, the effects of in-field spatial heterogeneity on crop yields, in particular triticale,... 相似文献
958.
X M Liu M N Zakaria M W Islam R Radhakrishnan A Ismail H B Chen K Chan A Al-Attas 《Fitoterapia》2001,72(5):487-491
The 10% ethanol extract of the aerial parts of Calligonum comosum (50--400 mg/kg, i.p.) significantly reduced the increase in hind paw oedema induced by carrageenan in rats. Following sub-acute oral administration of the extract (50 and 100 mg/kg, daily for 14 days), a significant anti-inflammatory activity in the cotton pellet model was observed. Pre-treatment with the extract (100, 200 and 400 mg/kg) produced a significant and dose-dependent inhibition to the acute gastric ulcers induced by phenylbutazone, indomethacin, 0.2 N NaOH and 80% ethanol. 相似文献
959.
960.
M. Rafiqul Islam Abdul Hamid Qazi Abdul Khaliq Jalal Uddin Ahmed M. Moynul Haque M. Abdul Karim 《Euphytica》2007,156(1-2):247-255
The study was an exploratory in nature conducted using a large number of mungbean (Vigna radiata L. Wilczek) genotypes of diverse growth habit and adaptive characters. Soil flooding induced changes in eleven morpho-physiological
characters of one-week old seedlings of 530 mungbean genotypes was compared in the study. The first and second principal components
(PC) of principal component analysis (PCA) results accounted for 58 and 14%, respectively of the total variations of mungbean
genotypes. The variation for first PC was composed mainly of relative dry weight (DW) of shoot and leaf as well as total DW.
The second PC distinguished the genotypes that produced larger root system. There were seven clusters distinguished in the
cluster analysis. The genotypes in cluster 4 and 6 performed better in respect of relative total DW and relative root DW,
respectively and hence having flooding tolerance. The genotypes in clusters 7 and 1 performed very poorly and those of under
clusters 3, 2 and 5 were moderate to poor. D2 analysis indicated that the clusters differed significantly from each other. Discriminant function analysis (DFA) reaffirmed
that more than 90% of the genotypes were correctly assigned to clusters. Both PCA and DFA confirmed that the relative total
DW followed by shoot and leaf DW as well as leaf area were the major discriminatory variables and the root : shoot ratio and
root DW were the secondary important variables to distinguish genotypes into groups. In this study, multivariate analyses
were used in identifying the mungbean genotypes of desirable traits for flooding tolerance. 相似文献