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131.
应用Wenner结构原理估计沙地松树人工林土壤含水量   总被引:3,自引:0,他引:3  
To estimate the mean value of surface soil water content rapidly, accurately, and nonintrusively, field investigations on soil electrical resistivity (SER) with the Yokogawa 324400 earth resistivity meter and the surface (0-150 cm) soil water content (SWC) with time domain reflectometry (TDR), together with the abiotic factors including soil texture, structure, and salinity concentrations were conducted in the Mongolian pine (Pinus sylvestris var. mongolica) plantations on a sandy land. The measurement of SER was based on the 4-probe Wenner configuration method. Relationships between the values of SWC and SER were obtained based on analysis of the abiotic factors of the research site, which play a key role in affecting the soil electrical resistivity. Results indicate that the SER meter could be used to estimate the mean value of SWC in the Mongolian pine plantations on the sandy land during the growing seasons. The bulky nature of the equipment simplified the cumbersome measurements of soil water content with the general methods. It must be noted that the Wenner configuration method could only provide the mean values of the SWC, and the soil texture, structure, temperature, and solute concentrations influenced the SER and further affected the estimation of the SWC by the SER meter. Therefore, the results of this study could be applied on a sandy land during the growing seasons only. However, the SWC of other soil types also may be obtained according to the individual soil types using the procedures of this study.  相似文献   
132.
蒙古高原草原土壤微生物量碳氮特征   总被引:48,自引:0,他引:48  
李香真  曲秋皓 《土壤学报》2002,39(1):97-104
沿着水分梯度采集了蒙古高原不同草原类型表层土壤样品 1 44个 ,分析了土壤微生物量C、N含量及其与年平均温度和降雨量的关系。结果表明 :蒙古高原草原土壤微生物量C、N与土壤有机C、全N、降雨量、温度均表现出了很好的相关性。微生物量C变化在5 1 7~ 797mgkg- 1之间 ,微生物量N变化在 1 1 0~ 1 1 8 6mgkg- 1之间。微生物量C∶N比变化在 5~ 9之间。土壤微生物量碳 (Cmic)占土壤有机碳 (Corg)的比例 (Cmic Corg)变化在 1 1 5 %~ 4 1 %之间 ,Cmic Corg与土壤有机C、全N、降雨量均成显著的负相关。土壤呼吸表现为草甸草原土壤 >典型草原 >荒漠草原 ,土壤呼吸与降雨量显著正相关 ,与温度显著负相关。呼吸熵 (QCO2 )与降雨量成二次抛物线关系。放牧对微生物量的影响与不同草原类型和放牧率有关。  相似文献   
133.
樟子松节子的大小及分布   总被引:2,自引:0,他引:2  
以不同树龄、不同密度的樟子松(Pinus sylvestris var.mogolica)人工林为研究对象,基于6块标准地中30株样木树干解析和节子剖析数据,揭示节子的垂直分布和水平分布规律,分析不同林分条件下节子分布规律的变化。结果表明:节子直径的垂直分布趋势是从伐根到大约树高的45%处逐渐增加,然后向上逐渐减小,但减小趋势趋于平缓;节子的水平分布服从均匀分布;不同林分条件下,樟子松节子的垂直分布状况不相同,随着林分密度的增大,节子直径的最大值逐渐减小,而且最大节子在树干上的位置也逐渐升高;随着林分树龄的增大,节子直径的最大值也逐渐增大,但是最大值出现的位置不变。节子直径最大值可以通过林分密度、胸径和枝下高建立的模型来描述;节子的频数分布呈现正态分布的趋势。  相似文献   
134.
食物质量对长爪沙鼠体重和褐色脂肪组织重量的影响   总被引:1,自引:0,他引:1  
为了测定不同食物质量(高脂肪低纤维和低脂肪高纤维)对长爪沙鼠体重和褐色脂肪组织(BAT)重量的影响,进一步确定食物质量对小哺乳动物体重调节的贡献率以及能量消耗在动物体重长期维持平衡中的作用,将动物分成高脂肪低纤维食物自由取食和低脂肪高纤维食物自由取食二组,驯养6周后,测定动物的体重和BAT重量。结果表明:食物质量对长爪沙鼠的体重有显著影响,在高脂肪含量条件下其体重显著增加,而在高纤维含量食物条件下,其体重增长较慢;食物质量对长爪沙鼠的BAT重量也有显著的影响,低脂肪高纤维组其BAT重量显著低于高脂肪低纤维组BAT重量,这也进一步验证了食物诱导产热的假说。  相似文献   
135.
A subcutaneous mass was found in the lower ventral neck region of a 55-week-old male Mongolian gerbil (Meriones unguiculatus). Histopathologically, the mass involved salivary glands and featured diffuse proliferation of pleomorphic neoplastic cells with large necrotic foci. The lesion was well demarcated from the surrounding tissue, although invasive growth to fibrous septa was occasionally observed. The neoplastic cells were mainly arranged in irregular sheets with severe cellular atypia, round to oval nuclei and varying amounts of eosinophilic cytoplasm. Mitotic figures and multinucleated giant cells were frequent. Immunohistochemical analysis revealed that the neoplastic cells were strongly positive for vimentin and S-100 and negative for NSE, cytokeratin, α-SMA, c-kit, factor VIII, CD34, α-1-antitrypsin, lysozyme and MSR-A. Based on the results, the mass was diagnosed as an undifferentiated sarcoma of the salivary gland. To the best of our knowledge, this is the first report of such a tumor in Mongolian gerbils.  相似文献   
136.
We determined the sequence of the immunoglobulin gamma heavy‐chain constant (IGHC) region of the Mongolian gerbil (Meriones unguiculatus). To isolate a part of the IGHC complementary DNA, we designed primers on the basis of highly conserved sequences in mouse, rat and hamster. The deduced IGHC is structurally similar to counterparts in other mammalian species and shows 84.6% identity to the IGHC of hamster IgG, 76.6% to rat IgG1, 83.3% to rat IgG2a, 78.1% to mouse IgG1, 81.8% to mouse IgG2a, 79.1% to mouse IgG2b and 79.2% to mouse IgG3 at the nucleotide level. The results suggest that gerbil IgG is closely related to hamster IgG and rat IgG2a.  相似文献   
137.
The Mongolian sheep ear marginal tissue fibroblast cell line (MSF32) from 32 samples was successfully established by using primary explants technique and cell cryoconservation technology. MSF32 cells were adherent, with a population doubling time of 28.2 h. Chromosome analysis showed that >90.2% of cells were diploid (2n = 54) prior to cell passage 4. Isoenzyme analyses of lactate dehydrogenase and malate dehydrogenase showed that the MSF22 cells had no cross‐contamination with other species. Tests for cell line contamination with bacteria, fungi, viruses and mycoplasmas were also negative. Plasmids encoding the fluorescent proteins pEGFP‐N3, pEGFP‐C1, pECFP‐N1, pECFP‐mito, pDsRed1‐N1 and pEYFP‐N1 were transfected into cells to study exogenous gene expression in the cells. The plasmid transfection efficiency was between 12.3% and 63.3%. Every index of the MSF32 cell line meets all the standard quality controls of American Type Culture Collection (ATCC). Not only has the genetic resources of the Mongolian sheep been preserved at the cell level, but also valuable materials had been provided for genome, postgenome and somacloning research.  相似文献   
138.
卫拉特蒙古,即西蒙古在历史发展过程中,与周边民族进行文化交流而形成了具有区域特色的卫拉特蒙古文化。其中宗教文化也具有明显的区域特色。本文主要从卫拉特蒙古人的日常生活习俗,人生礼仪中的信仰习俗和节日庆典中的游艺习俗等方面论述了卫拉特蒙古多元宗教观念的表现形式。  相似文献   
139.
[目的]通过对蒙古牛线粒体DNA(mtDNA)的基因组进行测序,探究蒙古牛的mtDNA基因组遗传多样性与母系起源。[方法]采用DNA提取、三代测序及生物信息学方法。[结果]在36头蒙古牛mtDNA全基因组序列中,共检测到22种不同的单倍型,平均单倍型多样度(Hd)为0.970,平均核苷酸多样度(Pi)为0.00845,表明蒙古牛有丰富的母系遗传多样性。构建的IQ系统发育树发现,蒙古牛具有瘤牛和普通牛两个母系支系。[结论]蒙古牛有丰富的母系遗传多样性,拥有普通牛和瘤牛两个母系起源,以普通牛起源为主。  相似文献   
140.
影响内蒙古白绒山羊性状的非遗传因素分析   总被引:6,自引:0,他引:6  
本研究对内蒙古白绒山羊早期生长性状和抓绒性状的非遗传因素进行分析,结果表明,出生年份、场、性别、出生类型、母亲年龄对出生重、断乳重以及日增重均有极显著的影响(p<0.01)。断乳时期对断乳重和日增重也有显著的影响(p<0.05),出生月份对断乳重有极显著影响(p<0.01),周岁重受测定年份、场和性别的极显著影响(p<0.01)。出生类型对所有抓绒性状影响都不显著(p>0.05),场和年龄对所有抓绒性状都影响极为显著(p<0.01),测定年份对绒长度和毛长影响不显著(p>0.05),而对其他性状影响均显著,性别对绒细度影响不显著(p>0.05),对其他性状影响均显著。有些性状还受到其他非遗传因素互作效应的影响。  相似文献   
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