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The restoration potential of Sweetgrass (Anthoxanthum nitens (Weber) Y. Schouten & Veldkamp) was evaluated through a field experiment conducted on Kanatsiohareke, a Mohawk farm, and at the LaFayette Experiment Station near Syracuse, New York. The effects of competition reduction and two cover crops on Sweetgrass reestablishment success were examined. Sweetgrass was planted under four treatments: Sweetgrass alone; with existing, old‐field vegetation; with a cover crop of Hairy vetch (Vicia villosa); and with a cover crop of Annual (Italian) ryegrass (Lolium multiflorum). The experiment consisted of five replicates of the four treatments at both LaFayette and Kanatsiohareke. Sweetgrass biomass, height, reproduction rate, and survivorship were greatest in plots that were weeded to eliminate competition and in plots with Hairy vetch as a cover crop. A cover crop of Annual ryegrass resulted in reduced Sweetgrass growth and reproduction. The results of this field experiment indicate that there is great restoration potential for Sweetgrass because it is easily transplanted and reproduces vigorously. For 2.25‐m2 plots, Hairy vetch is an effective cover crop for Sweetgrass. Planting the Sweetgrass with Hairy vetch generated properties of the grass that are desired by basketmakers, such as abundance and tall blades. This technique also allowed for a relatively non–labor intensive method of cultivation. Reestablishment of Sweetgrass offers the members and visitors of Kanatsiohareke the means to continue to use the plant, strengthen traditional practices associated with Sweetgrass, and benefit economically by selling baskets and medicine made with Sweetgrass. 相似文献
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S. Biondi 《Plant biosystems》2013,147(1-6):29-42
Abstract This article surveys the techniques and approaches used in the in vitro propagation of economically important plants. The current state of the art for each major class of plants, namely ornamentals, vegetable and agronomic crops, temperate fruits and forest trees is described. The advantages of vegetative propagation in general and the specific advantages which micropropagation offers in the domestication, breeding and conservation of plants are listed. Specific problems associated with in vitro propagation such as juvenility vs maturation, vitrification, rooting and morphological or physiological variations are discussed. 相似文献
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The potato has tremendous potential as a transgenic crop and is a good model system by which to analyse metabolic regulation
and gene expression. The potato’s difficult genetics, but ease of genetic transformation and its clonal means of propagation
make it ideal for applied agricultural molecular genetics. Thus, the next 4 years promise to put the potato (with a diversity
of transgenic constructs expressed) in the limelight as many of the first transgenic agricultural products enter the marketplace. 相似文献
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目的 将工作场所无礼行为量表引入新入职护士群体,并探究新入职护士经历工作场所无礼行为对其离职意愿的影响。方法 通过问卷调查法,调查了新参加工作三年内的护士696人。采用探索性因子分析法和阶层回归分析进行数据分析。结果 工作场所无礼行为量表包含2个维度下的12个测量条目,问卷的格朗巴赫一致性系数为0.893,量表具有良好的结构效度和预测效度, 新入职护士经历工作场所无礼行为对离职意愿具有显著的正向预测作用(β= 0.352,P<0.01)。结论 新入职护士经历工作场所无礼行为量表具有良好的信效度,同时,经历高水平的工作场所无礼行为的新入职护士心理压力增强及工作嵌入度降低,进而她们的离职意愿增高。 相似文献
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As sessile organisms, plants are unable to escape from the many abiotic and biotic factors that cause a departure from optimal conditions of growth and development. Low temperature represents one of the most harmful abiotic stresses affecting temperate plants. These species have adapted to seasonal variations in temperature by adjusting their metabolism during autumn, increasing their content of a range of cryo‐protective compounds to maximise their cold tolerance. Some of these molecules are synthesised de novo. The down‐regulation of some gene products represents an additional important regulatory mechanism. Ways in which plants cope with cold stress are described, and the current state of the art with respect to both the model plant Arabidopsis thaliana and crop plants in the area of gene expression and metabolic pathways during low‐temperature stress are discussed. 相似文献