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861.
1985—1986年,分别以夏播和春播大豆为材料,研究大豆不同抗旱品种根系的生理功能.结果表明:大豆抗旱品种根系内可溶性糖和游离氨基酸的含量较高,并在开花结荚期出现高峰。根细胞的基态渗透浓度较大,渗透吸水能力较强.根系的伤流液较多,伤流液的电导率也较高。抗旱品种叶片含水量多,水势较高。  相似文献   
862.
首先运用EXCEL绘制出了专业品酒员的品评分数相关图表,其次利用MATLAB和线性回归的思想来拟合数据,具体研究了总酚、单宁和总酸这3个理化指标对葡萄酒质量的影响。数据分析表明总酚、单宁和总酸与葡萄酒的等级划分呈明显的正相关性,即总酚、单宁和总酸含量越高,葡萄酒的等级越高。  相似文献   
863.
SUMMARY

One can predict a future in which professional plant breeding, especially in the private sector, will be significantly scaled back, and advanced biotechnologies (e.g., genetic engineering) will be forbidden for use in plant breeding. Alternatively, one can predict a future in which commercialism will rule all sectors. But a more optimistic outlook predicts that the current tripartite division of responsibilities will prevail: Private Sector, Public Sector, and Participatory (i.e., farmer-breeder partnerships). The global plant breeding system is composed of separate organs, each essential for the survival of the whole but each with a different function. All parts work together for the good of the whole.  相似文献   
864.
次生代谢产物小檗碱、掌叶防己碱和药根碱是黄檗中重要的药用生物碱,本研究在吉林省5 个林业局选取了65 株不同年龄的天然黄檗,利用反相高效液相色谱法研究了黄檗多器官中3 种生物碱含量的季节差异。结果表明:小檗碱在根皮、多年生枝、当年生枝和叶中的季节差异显著,各器官中小檗碱含量夏季最低(叶除外);叶中小檗碱含量,在各个龄组均表现为从春到秋含量依次升高,变化幅度在0.017 ~0.124 mg/ g 之间;小檗碱在根皮中最高, 平均值达到24.27 mg/ g,其余依次是茎皮、多年生枝皮、当年生枝和叶片。掌叶防己碱在根皮、茎皮、当年生枝、叶和幼龄阶段的多年生枝皮中的季节差异显著,秋季含量最高(叶除外);叶中掌叶防己碱含量,在各个龄组均表现为春季最高;掌叶防己碱在茎皮中含量最多,平均值为7.02 mg/ g,其余含量由大到小依次是多年生枝皮、根皮、当年 生枝和叶。药根碱在茎皮、多年生枝皮、当年生枝、叶和成熟阶段的根皮中的季节差异显著,多数器官夏季含量最 低;叶中药根碱含量,在各个龄组均表现为春季最高;药根碱在各个器官中的分布规律与小檗碱一致,根皮中含量最高,平均值为0.84 mg/ g,其余含量由大到小依次是茎皮、多年生枝、当年生枝叶。   相似文献   
865.
The genotype of an individual and the environment as the maternal ability of its dam have substantial effects on the phenotype expression of many production traits. The aim of the present study was to estimate the (co)variance components for worm resistance, wool and growth traits in Merino sheep, testing the importance of maternal effects and to determine the most appropriate model for each trait. The traits analyzed were Greasy Fleece Weight (GFW), Clean Fleece Weight (CFW), average Fibre Diameter (FD), Coefficient of Variation of FD (CVFD), Staple Length (SL), Comfort Factor (CF30), Weaning Weight (WWT), Yearling Body Weight (YWT) and Faecal worm Egg Count (FEC). The data were recorded during a 15-year period from 1995 to 2010, from Uruguayan Merino stud flocks. A Bayesian analysis was performed to estimate (co)variance components and genetic parameters. By ignoring or including maternal genetic or environmental effects, five different univariate models were fitted in order to determine the most effective for each trait. For CVFD and YWT, the model fitting the data best included direct additive effects as the only significant random source of variation. For GFW, CFW, FD, SL and CF30 the most appropriate model included direct-maternal covariance; while for FEC included maternal genetics effects with a zero direct-maternal covariance. The most suitable model for WWT included correlated maternal genetic plus maternal permanent environmental effects. The estimates of direct heritability were moderate to high and ranged from 0.15 for log transformed FEC to 0.74 for FD. Most of the direct additive genetic correlation (rg) estimations were in the expected range for Merino breed. However, the estimate of rg between FEC and FD was unfavourable (−0.18±0.03). In conclusion, there is considerable genetic variation in the traits analyzed, indicating the potential to make genetic progress on these traits. This study showed that maternal effects are influencing most of traits analyzed, thus these effects should be considered in Uruguayan Merino breeding programs; since the implementation of an appropriate model of analysis is critical to obtain accurate estimates.  相似文献   
866.
主产区与主销区鸡蛋价格传导机制分析   总被引:1,自引:1,他引:0  
针对鸡蛋主产区山东、河北、河南、辽宁、江苏与鸡蛋主销区北京的鸡蛋价格水平和价格走势趋于一致的现象,利用2000-2011年各省(市)的鸡蛋价格月度数据,采用单位根检验、格兰杰因果关系检验、VAR模型、脉冲响应函数分析和方差分解方法,对鸡蛋主产区与主销区的鸡蛋价格传导机制进行了研究.结果表明:主产区的鸡蛋价格能够用于预测主销区北京的鸡蛋价格;主产区的鸡蛋价格对北京鸡蛋价格的传导均存在1个月的时滞;主产区山东的鸡蛋价格波动对北京鸡蛋价格波动的影响最大.为避免北京鸡蛋价格出现大幅波动,建议在鸡蛋主产区建立蛋鸡疫情防控体系,鸡蛋主销区提高鸡蛋市场流通效率,在鸡蛋主产区与主销区之间建立联合预警机制.  相似文献   
867.
The physicochemical and nutritional quality of four chalky mutants (JM1-4) rice and their parent 93-11 were investigated. JM1 and JM4 are white-belly mutants, and JM2 is white-core mutant, while JM3 is floury mutant. JM2 is also a high amylose mutant with AAC of 29%. JM3 had the lipid content nearly three times of the parent, so it is also a high lipid mutant. JM1 had similar pasting viscosities with the parent, while JM2 and JM3 had smaller breakdown and setback than 93-11. JM2 had lower enthalpy of gelatinization, but higher enthalpy of retrogradation, so it had highest retrogradation percentage. JM3 had the highest accumulation of amino acids, fatty acids, and some major mineral elements such as P, K, Mg and Ca. The amino acids and fatty acids had negative correlation with PV, HPV and CPV. The pleiotropic effects caused by the mutations on starch and lipid metabolism deserve further investigation.  相似文献   
868.
Interleukin 17 (IL-17) mediates neutrophil migration to the lungs during acute inflammation, potentially leading to lung tissue damage. In the present study, we evaluated whether IL-17 could facilitate certain neutrophil functions in a mouse model. Mice were divided into four groups and intranasally challenged with PBS (1 = Control), Influenza A (H1N1) and Klebsiella pneumoniae (2 = Mix), Influenza A alone (3 = Flu), or K. pneumoniae (4 = KP) alone. Bone marrow, BAL cells, and lung specimens were collected seven days post-challenge for analysis. Mice in the Flu group showed the highest mortality rate. Neutrophils were the prominent cell type in BAL from Mix and KP, whereas lymphocytes were most numerous in Flu. Lesions in the lungs revealed considerably damage in the Mix, Flu, and KP groups. Isolated bone marrow-derived neutrophils were in vitro primed with mouse recombinant IL-17A protein (rIL-17A) followed by various functional assays. The reactive oxygen species (ROS) levels in rIL-17A primed cells showed significant elevations in all groups. Phagocytosis and bacterial destruction showed no significant difference between (+) or (−) rIL-17A groups. The formation of neutrophil extracellular traps (NETs) in rIL-17A-primed neutrophils showed elevated NET production. We next monitored expressions of genes in neutrophils. IL-17A mRNA expression was significantly increased in Mix and Flu; IL-1β mRNA only significantly increased in Flu, and IL-17RA showed constitutive expressions in all groups. In summary, neutrophils may cause tissue damage during lung inflammation through specific functions influenced by IL-17.  相似文献   
869.
基于多目标遗传算法的管孔组合特征识别   总被引:1,自引:0,他引:1  
提出一种管孔组合方式的自动识别方法.提取木材显微横切面的边缘后,基于类圆区域面积直方图,通过最大类间方差将封闭区域分为2类,将导管与其他形状相似、大小不同的组织分开;同时,引入封闭区域平均面积作为另一目标函数.最后采用管孔集邻接度来判断管孔的组合方式.试验表明该方法能够对各种导管的分布和组合获得满意的分割效果,并给出管孔的组合方式.  相似文献   
870.
王嫱 《农业工程》2012,2(4):11-15
ISO11783的目的是为电子系统提供开放的互联系统。它趋于用电子控制系统(ECUs)使彼此通讯,提供标准化系统。ISO11783-4部分定义了网络层,即控制功能块(Control Functions)在ISO11783-4网络的不同部分之间的通信要求和服务需求。各种类型的网络互联单元定义在ISO11783-4部分。  相似文献   
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