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61.
AFS系统中,传感器信号采集处理、伺服电机调节机构及控制方法是影响其性能的3个主要因素。文章对AFS系统水平随动机构中步进电机的调节机构与控制方法进行了研究和设计,重点是研究其调节机构并据此建立运行步数与大灯实际偏转角度的数学模型,对控制样机的控制程序应用线性化处理及误差补偿的方法进行了算法优化设计,实现了应用模糊自适应PD控制算法对AFS水平随动执行机构的控制设计。进行仿真实验并在上海大众斯柯达昊锐车型SK-98760型前照灯总成上测试,结果表明所设计的系统具有良好的控制效果。  相似文献   
62.
地沟油流向监管是我国食品安全领域的热点问题.本文从政府监管角度,运用委托代理理论研究了信息不对称下政府对地沟油流向监管的问题,考虑了激励机制和惩罚机制,给出了最优合同设计,防止地沟油进入非法利益链条回流餐桌,同时促使地沟油流向生物质能源链条变废为宝.论文的研究结果为政府在地沟油监管政策制定方面提供一定的参考.  相似文献   
63.
Summary Although almost all methods of mass measurement of regulatory peptides still depend on the high affinity antibody, the traditional Yalow and Berson radioimmunoassay technique is becoming outdated. Pure monoclonal antibodies allow excess antibody two site assay techniques with a variety of different labels (preferentially non-radioactive) of great sensitivity and speed. The large amounts of particular monoclonal antibodies available allow several different laboratories to use the same reagents and have increased comparability. Unfortunately many regulatory peptides exist in multiple molecular forms and attention must be paid to antibody region specificity. Improved methods of extraction of regulatory peptides from plasma tissue allow more accurate quantitation. New techniques for rapid high resolution chromatography make distinction of different molecular forms much easier than hitherto. Better education in techniques and/or attention to inter-assay standards are necessary to improve the comparability of regulatory peptide measurement in the future.  相似文献   
64.
针对单一数据集构建基因调控网络算法数据量不足及构建网络结果不精确的问题, 提出一种基于能力与信任(AP)的数据源融合算法. 该算法将基因表达数据、 蛋白质相互作用数据和基序数据集, 分别通过控制与被控制双向数据流传输来分析和构建基因调控网络, 并与ReMoDiscovery,CLR和C3Net三种已开发模型在酵母全基因组网络构建结果的AUC值进行对比. 对比结果表明, 该算法在构建基因调控网络算法方面执行效率更高、 收敛性更强.  相似文献   
65.
Summary Precursors to regulatory peptides undergo maturation processes which include protelytic processing. The enzymes involved in this process remove the hydrophobic peptide located at the amino-terminus of the precursor. Endoprotease cleavage also occurs at single and two adjacent basic residues, this is followed by a removal of basic residues located at the C-terminus of the peptides by a carboxypeptidase-like enzyme.  相似文献   
66.
During the growth and development of skeletal muscle cells and adipose cells, the regulatory mechanism of micro-effect polygenes determines porcine meat quality, carcass characteristics and other relative quantitative traits. Obese and lean type pig breeds show obvious differences in muscle growth and adipose deposition; however, the molecular mechanism underlying this phenotypic variation remains unknown. We used pathway-focused oligo microarray studies to examine the expression changes of 140 genes associated with muscle growth and adipose deposition in longissimus dorsi muscle at six growth stages (birth, 1, 2, 3, 4 and 5 months) of Landrace (a leaner, Western breed) and Taihu pigs (a fatty, indigenous, Chinese breed). Variance analysis (ANOVA) revealed that differences in the expression of 18 genes in Landrace pigs and three genes in Taihu pigs were very significant (FDR-adjusted permutation, P 〈 0.01) and differences for 22 genes in Landrace pigs and seven genes in Taihu pigs were significant (FDR-adjusted permutation, P 〈 0.05) among six growth stages. Clustering analysis revealed a high level of significance (FDR-adjusted, P 〈 0.01) for four gene expression patterns, in which genes that strongly up-regulated were mainly associated with the positive regulation of myofiber formation and fatty acid biogenesis and genes that strongly down-regulated were mainly associated with the inhibition of cell proliferation and positive regulation of fatty acid β-oxidation. Based on a dynamic Bayesian network (DBN) model, gene regulatory networks (GRNs) were reconstructed from time-series data for each pig breed. These two GRNs initially revealed the distinct differences in physiological and biochemical aspects of muscle growth and adipose deposition between the two pig breeds; from these results, some potential key genes could be identified. Quantitative real-time RT-PCR (QRT-PCR) was used to verify the microarray data for five modulated genes, and a good correlation between  相似文献   
67.
论述了控制性详细规划编制的必要性,阐述了机场大道两侧控制性详细规划指标体系的构成,分析了机场大道两侧控规指标体系确定的依据与作用。  相似文献   
68.
A key regulatory mechanism in cell motility is the control of myosin activity, which in non-muscle cells is determined by phosphorylation of the myosin regulatory light chain (MRLC). Here we show that MRLC-interacting protein (MIR)-interacting saposin-like protein (MSAP) enhances cell spreading in fibroblasts and migration of rat C6 glioma cells through increases in MRLC phosphorylation. Overexpression of MSAP enhanced the motility of glioma cells measured in matrigel invasion chambers and using a scratch assay. Downregulation of MSAP by RNA interference significantly decreased glioma cell migration and phosphorylation of MRLC. Inhibition of the corresponding MRLC kinase by ML-7 did not affect migration of MSAP-overexpressing cells. The present results show that MSAP controls glioma cell migration via enhancement of MRLC phosphorylation. This effect is independent of the activity of MRLC kinase. Thus, MSAP is a novel modulator of cell motility that influences migration of glioma cells and possibly other tumors.Received 9 February 2005; received after revision 2 March 2005; accepted 21 March 2005  相似文献   
69.
苔藓植物的主要次生代谢产物与有害生物防治   总被引:35,自引:1,他引:34  
汪庆  罗宣 《贵州科学》2001,19(4):93-100
苔类的主要次生代谢产物为倍半萜、联苄和二联苄,藓类则以黄酮为主。苔类植物中的抗菌、抗真菌活性成分有异戊烯基联苄、地钱素A、网地藻烷型二萜及其衍生物、酚基倍半萜、a-santonin、核子木素A、B及其衍生物、三裂鞭台醇、Dicrnenone A、DicranenoneB1等。许多苔类中富集的半月苔认为可能完全足以抵御真菌的感染。藓类中常见的双黄酮和聚酚基化合物能够抵御真菌感染和昆虫的摄食。泥炭藓醇是导致泥炭藓和灰藓类分解较慢的因素之一,苯甲酸苄酯类对昆虫和螨类是致命的,草酸对植食性昆虫有排斥作用,藓类枝条内的protocatechiuc和五倍子酸对刺激蛾科昆虫有拒食作用,其它包括绿片酮pinguisone、囊绒苔醛、桉叶油内酯、大根香叶烷、倍半萜内酯、补身基烷内酯、Gymnocolin。Albicanol aceate对金鱼有明显的拒食作用,一系列天然的补身烷及相关的合成化合物被证明对蚜虫有拒食作用。Polygodial被认为是作为昆虫拒食剂最有效的天然产物之一,还能够抑制鱼类的摄食。浮苔素A、浮苔素B、半月苔酸、半月苔甲酯、和5-羟基半月苔酸有灭螺活性。绝大多数苔藓的粗提物,特别是含有芳香性化合物的,表现出抑制发芽、根伸长、及胚芽鞘的生长的活性。半月苔酸、isobidyclogermacrenal、指叶苔醛、指叶苔醇及其羟基衍生物、硬指叶苔醇、一些2,3-断香橙烷型倍半萜半缩醛、甲氧基plagiochilines、(一)-polygodial、折瓣苔烷型二萜化合物、和3a,4a-epoxy-5a-acetoxy-18-hydroxysphenolobal13E,16E-diene对植物生长有抑制作用。  相似文献   
70.
论控制性详细规划   总被引:1,自引:0,他引:1  
简要介绍了控制性详细规划这一新型城市规划法规的基本理论和规划控制体系,阐述了实施效果的重要性,并且分析了控制性详细规划的编制方法和成果表现方式。以期城市规划工作人员不断改进控规的编制方法,提高控规编制的科学性,保障控规的实施权威性。  相似文献   
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