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71.
Agroforestry Systems - A large number of people in developing countries have traditionally depended on products derived from plants, especially from forests, for curing human and livestock... 相似文献
72.
植物组培育苗工厂电脑管理系统的设计与应用 总被引:2,自引:0,他引:2
研制了一个组培室数据库管理系统,通过检索可方便地查询培养室内各种瓶苗的动态变化和某种组培育苗状态及积累的组培育苗资料,为最适宜培养条件的电脑筛选打下基础。文中简单介绍了该系统的运行条件,数据结构和技术功能等。 相似文献
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Crop productivity under differently lopped canopies of multipurpose trees in Central Himalaya, India 总被引:3,自引:1,他引:3
Ficus species are multipurpose trees well known by rural populations in Sahelian and Sudanian zones of Africa. Their uses are well documented but their amenability for vegetative propagation has not been extensively studied. This paper compares the rooting ability of stem and aerial root cuttings from thirteen Ficus species found in West Africa. It highlights the differences between species belonging to the sub-genera Sycomorus and Urostigma. The former show no capacity to propagate from cuttings whereas the latter, with epiphytic development, can be propagated by cuttings, although this capacity varies among species. Thus, F. thonningii, F. leprieurii and F. ovata are easily propagated, while F. platyphylla and F. elasticoides are propagated with difficulty. The rooting capacity also varies depending on the cutting material used. It decreases in the following order: long leafless hardwood cuttings (pole) > nodal cuttings > apical cuttings. Rooting potential increases when the cuttings are harvested towards the end of the dry season(March to May). Aerial root can be used for cuttings in all species of the sub-genus Urostigma. The capacity of root cuttings to regenerate is greatest when cuttings are collected at the beginning of the dry season (November). In this case, wound-induced adventitious roots arise at the basal end of the cutting while de novo buds are developed from the cambium at the distal end. The subsequent morphological development is identical to that of a stem cutting. These results clarify and allow the optimal use of the knowledge and methods developed by the indigenous people of the Sahel and could assist and promote fig tree (Ficus sp.) domestication in the dry tropics.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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A new phorbol diester, 13-O-myristyl-20-O-acetyl-12-deoxyphorbol (1), has been isolated from the benzene extract of the heartwood of Aleurites moluccana. In addition, hentriacontane, 6,7-dimethoxycoumarin, 5,6,7-trimethoxycoumarin and beta-sitostenone are being reported for the first time from this species. 相似文献
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锦鲤选美的不同等级之间具有高相似度的特点,目前都是人工进行选美分级。为解决人工选美所存在的效率低、主观性强、成本高的问题,提出了一种基于迁移学习和改进ResNeXt50残差网络的锦鲤选美方法。本文首先构建了红白、大正、昭和3种锦鲤的选美等级数据集。其次,采用迁移学习策略提高训练速度,并从SE注意力模块、Hardswish激活函数和Ranger优化器3方面对ResNeXt50模型进行了改进,构建了SH-ResNeXt50锦鲤选美分级模型。试验结果表明:SH-ResNeXt50模型有效提升了锦鲤选美的等级分选能力,模型准确率达95.6%,损失值仅0.074,优于常用的AlexNet、GoogLeNet、ResNet50和ResNeXt50网络模型。最后,采用Grad-CAM分析SH-ResNeXt50模型的可解释性,结果表明SH-ResNeXt50模型和人工识别的感兴趣区域基本一致。本文所提出的方法实现了具有高相似度的锦鲤不同等级的智能分选,对其它具有高相似度的生物等级分选具有借鉴意义。 相似文献
79.
Hsieh YH Ofori JA Rao Q Bridgeman CR 《Journal of agricultural and food chemistry》2007,55(16):6720-6725
Bovine plasma proteins are used as high-quality protein supplements in animal feed and as binders or colorants in food for human consumption. Religious observance, as well as recent fears of epidemic bovine spongiform encephalopathy, highlights the need for methods to detect bovine blood in processed food and animal feed for regulatory purposes, as the currently available methods are neither species-specific, blood-specific, nor valid for excessively heat-processed samples. This paper reports the development of monoclonal antibodies (MAbs) raised against bovine thermostable plasma proteins that display a unique species specificity pattern for plasma proteins. Immunoblotting revealed several thermostable antigenic proteins (10, 25, 40, and 60 kDa) in bovine plasma sterilized at 121 degrees C for 15 min. These MAbs can be employed individually or combined in immunoassays for analytical purposes and investigations of the chemical and biological properties of the thermostable plasma proteins identified here. 相似文献
80.
Expression profiling of transgenes (Cry1Ac and Cry2A) in cotton genotypes under different genetic backgrounds
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Kashif NOOR Hafiza Masooma Naseer CHEEMA Asif Ali KHAN Rao Sohail Ahmad KHAN 《农业科学学报》2022,21(10):2818-2832
Transgenic cotton carrying the Cry1Ac gene has revolutionized insect pest control since its adoption, although the development of resistance in insect pests has reduced its efficacy. After 10 years of cultivating Bacillus thuringiensis (Bt) cotton with a single Cry1Ac gene, growers are on the verge of adopting Bt cotton that carries the double gene (Cry1Ac+Cry2A) due to its better effectiveness against insect pests. Thus, the current study was designed to evaluate the role of each gene in the effectiveness of Bt cotton carrying the double gene. The expression levels of the Cry1Ac and Cry2A genes were evaluated in the leaves of 10 genotypes (2 parents and 8 F1 hybrids) at 30 days after sowing (DAS), while samples of leaves, bolls and flowers were taken from the upper and lower canopies at 70 and 110 DAS. The F1 hybrids were developed through reciprocal crosses between two Bt (CKC-1, CKC-2) and two non-Bt (MNH-786, FH-942) parents. The differential expression of transgenes was evaluated through Enzyme Linked Immuno-Sorbent Assay (ELISA). The results showed that the MNH786×CKC-1 hybrid had the highest concentrations of Cry1Ac gene at 30 DAS (3.08 µg g–1) and 110 DAS (1.01 µg g–1) in leaves. In contrast, the CKC-2×MNH-786 hybrid showed the lowest concentrations of Cry1Ac gene at 30 DAS (2.30 µg g–1) and 110 DAS (0.86 µg g–1). The F1 hybrid FH-942×CKC-2 showed the highest concentrations of Cry2A gene at 30 DAS (8.39 µg g–1) and 110 DAS (7.74 µg g–1) in leaves, while the CKC-1×MNH-786 hybrid expressed the lowest concentrations of Cry2A gene at 30 DAS (7.10 µg g–1) and 110 DAS (8.31 µg g–1). A comparison between the two stages of plant growth showed that leaves had the highest concentrations at 30 DAS, whereas the lowest concentrations were observed at 110 DAS for both genes in leaves. When the expression pattern was compared between various plant parts in genotype CKC-2, it was found that leaves had higher concentrations of Cry1Ac (3.12 µg g–1) and Cry2A (8.31 µg g–1) at 70 DAS, followed by bolls (Cry1Ac (1.66 µg g–1) and Cry2A (8.15 µg g–1)) and flowers (Cry1Ac (1.07 µg g–1) and Cry2A (7.99 µg g–1)). The genotype CKC-2 had higher concentrations of Cry1Ac (3.12 µg g–1) and Cry2A (8.31 µg g–1) in the upper canopy but less accumulation (2.66 µg g–1 of Cry1Ac, 8.09 µg g–1 of Cry2A) in the lower canopy at 70 DAS. Similarly, at 110 DAS, the expression levels of Cry1Ac and Cry2A in upper and lower canopy leaves were 1.52 and 7.92 µg g–1, and 0.99 and 7.54 µg g–1, respectively. Hence, the current study demonstrates that different genotypes showed variable expression for both of the Cry1Ac and Cry2A genes during plant growth due to different genetic backgrounds. The Cry2A gene had three-fold higher expression than Cry1Ac with significant differences in expression in different plant parts. The findings of this study will be helpful for breeding insect-resistant double-gene genotypes with better gene expression levels of Cry1Ac and Cry2A for sustainable cotton production worldwide. 相似文献