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121.
菜豆田两种潜叶蝇和主要天敌生态位研究 总被引:8,自引:0,他引:8
从生态位研究角度出发 ,采用 Hurlbert( 1978)生态位重叠和 L evins( 1968)生态位宽度指标 ,对严重危害菜豆的两种潜叶蝇 :美洲斑潜蝇 L iriomyza sativae Blanchard和豌豆潜叶蝇 Phytomyza atricor-nis Meig与主要天敌在时间和空间维度上的生态位重叠和生态位宽度作了定量分析。评价了天敌对猎物的时间及空间跟随作用和控制效果。研究表明 :寄生蜂、蜘蛛、龟纹瓢虫、异色瓢虫对豌豆潜叶蝇有较强的跟随作用和控制效果 相似文献
122.
湖北拟隐脉叶蝉属一新种(同翅目:叶蝉科:隐脉叶蝉亚科) 总被引:3,自引:2,他引:1
记述湖北省拟隐脉叶蝉属一新种,双枝拟隐脉叶蝉Sophonia biramosa sp.nov,新种模式标本保存在贵州大学昆虫研究所。 相似文献
123.
M Zió?kowska-Kochan G Sobczak-Kamińska R Mazur 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1992,47(14-15):327-328
Many countries are interested in the cost of therapy of the acute cerebral flow insufficiency leading to brain infarction. Total costs include: drugs, laboratory tests, nursing care, the cost of patients' food, equipment, amortization, hospital administration etc. The total expenditure for a 10-15-day treatment of the acute neurological incident depended on the severity of the disease and was 8 million ++ z?oty in case of mildly ill patient, 9 million in case of moderately severe disease, and 21 million z?oty in case of severely ill patient. If the costs of such tests as CT and TCD-scanning will be added, total cost will increase significantly. 相似文献
124.
Single Cell Transcriptome Amplification with MALBAC 总被引:1,自引:0,他引:1
125.
126.
Yuqian Shen Zi Chao Zhang Shanshan Cheng An Liu Jian Zuo Shuting Xia Xian Liu Wenhua Liu Zhengping Jia Wei Xie Junhai Han 《Molecular cell》2021,81(7):1425-1438.e10
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127.
128.
Lan Yan Xiang Rong Cheng Qi Zeng Jiang Jiang Qin Wei Dong Zhang Hui Zi Jin 《Biochemical Systematics and Ecology》2011,39(4-6):700-703
Three new aliphatic diterpenes (1–3), together with three known neoclerodane-type diterpenes (4–6) were isolated from the aerial parts of Inula nervosa Wall. The structures of 1-3 were elucidated on the basis of 1D and 2D spectroscopic analysis. Additionally, phytane-type and neoclerodane-type diterpenes have not been reported in any species of the genus Inula yet. The phytane-type and neoclerodane-type diterpenes obtained from I. nervosa Wall. suggest this plant maybe have remote genetic relations with other Inula species. 相似文献
129.
Neuropeptides function in animals to modulate most, if not all, complex behaviors. In invertebrates, neuropeptides can function as the primary neurotransmitter of a neuron, but more generally they co-localize with a small molecule neurotransmitter, as is commonly seen in vertebrates. Because a single neuron can express multiple neuropeptides and because neuropeptides can bind to multiple G protein-coupled receptors, neuropeptide actions increase the complexity by which the neural connectome can be activated or inhibited. Humans are estimated to have 90 plus neuropeptide genes; by contrast, nematodes, a relatively simple organism, have a slightly larger complement of neuropeptide genes. For instance, the nematode Caenorhabditis elegans has over 100 neuropeptide-encoding genes, of which at least 31 genes encode peptides of the FMRFamide family. To understand the function of this large FMRFamide peptide family, we isolated knockouts of different FMRFamide-encoding genes and generated transgenic animals in which the peptides are overexpressed. We assayed these animals on two basic behaviors: locomotion and reproduction. Modulating levels of different neuropeptides have strong as well as subtle effects on these behaviors. These data suggest that neuropeptides play critical roles in C. elegans to fine tune neural circuits controlling locomotion and reproduction. 相似文献
130.
Current stocks and potential of carbon sequestration of the forest tree layer in Qinghai Province,China北大核心CSCD
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Aims Our objective was to estimate the carbon storage in the forest tree layer in Qinghai Province, China. Methods Based on forest resource inventory data and field investigation data, we estimated the carbon storage, sequestration rate and potentials in the forest tree layer in the Qinghai Province. Important findings The carbon density and total carbon storage of forest tree layer in Qinghai Province was 76.54 Mg·hm-2 and 27.38 Tg, respectively, of which four forest types (Picea spp. forest, Cupressus funebris forest, Betula spp. forest and Populus spp. forest) accounted for 86.67% while their areas were 96.23% of total forest areas in Qinghai. The carbon density and carbon storage of Picea spp. forest was 106.93 Mg·hm-2 and 14.78 Tg, respectively, which was the largest among all forest types. The carbon storage of the forest tree layer at different stand ages followed the sequence of over-mature forest > middle-aged forest > mature forest > near-mature forest > young forest. In addition, the carbon storage of forest tree layer in the province increased from 23.30 Tg in 2003 to 27.38 Tg in 2011. The average annual growth of carbon and carbon sequestration rate were 0.51 Tg and 1.06 Mg·hm-2·a-1, respectively. The maximum and minimum of carbon sequestration rate were respectively found in Cupressus funebris forest (0.44 Mg·hm-2·a-1) and Betula spp. forest (-1.06 Mg·hm-2·a-1). The mean carbon sequestration potential reached 8.50 Tg in 2011, with the highest value found in Picea spp. forest (3.40 Tg). These findings suggested high carbon sequestration potential of forest tree layer in Qinghai Province. Therefore, the carbon storage in Qinghai Province could be increased through better forest management and utilization. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved. 相似文献