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1.
In the present work, we performed immunochemical studies of LPS, especially the O-specific polysaccharide (O-PS) of Aeromonas veronii bv. sobria strain K133, which was isolated from the kidney of carp (Cyprinus carpio L.) during an outbreak of motile aeromonad infection/motile aeromonad septicemia (MAI/MAS) on a Polish fish farm. The structural characterization of the O-PS, which was obtained by mild acid degradation of the LPS, was performed with chemical methods, MALDI-TOF mass spectrometry, and 1H and 13C NMR spectroscopy. It was revealed that the O-PS has a unique composition of a linear tetrasaccharide repeating unit and contains a rarely occurring sugar 2,4-diamino-2,4,6-trideoxy-D-glucose (bacillosamine), which may determine the specificity of the serogroup. Western blotting and ELISA confirmed that A. veronii bv. sobria strain K133 belongs to the new serogroup PGO1, which is one of the most commonly represented immunotypes among carp and trout isolates of Aeromonas sp. in Polish aquacultures. Considering the increase in the MAI/MAS incidences and their impact on freshwater species, also with economic importance, and in the absence of an effective immunoprophylaxis, studies of the Aeromonas O-antigens are relevant in the light of epidemiological data and monitoring emergent pathogens representing unknown antigenic variants and serotypes.  相似文献   
2.
Acute lung injury (ALI) afflicts approximately 200,000 patients annually and has a 40% mortality rate. The COVID-19 pandemic has massively increased the rate of ALI incidence. The pathogenesis of ALI involves tissue damage from invading microbes and, in severe cases, the overexpression of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). This study aimed to develop a therapy to normalize the excess production of inflammatory cytokines and promote tissue repair in the lipopolysaccharide (LPS)-induced ALI. Based on our previous studies, we tested the insulin-like growth factor I (IGF-I) and BTP-2 therapies. IGF-I was selected, because we and others have shown that elevated inflammatory cytokines suppress the expression of growth hormone receptors in the liver, leading to a decrease in the circulating IGF-I. IGF-I is a growth factor that increases vascular protection, enhances tissue repair, and decreases pro-inflammatory cytokines. It is also required to produce anti-inflammatory 1,25-dihydroxyvitamin D. BTP-2, an inhibitor of cytosolic calcium, was used to suppress the LPS-induced increase in cytosolic calcium, which otherwise leads to an increase in proinflammatory cytokines. We showed that LPS increased the expression of the primary inflammatory mediators such as toll like receptor-4 (TLR-4), IL-1β, interleukin-17 (IL-17), TNF-α, and interferon-γ (IFN-γ), which were normalized by the IGF-I + BTP-2 dual therapy in the lungs, along with improved vascular gene expression markers. The histologic lung injury score was markedly elevated by LPS and reduced to normal by the combination therapy. In conclusion, the LPS-induced increases in inflammatory cytokines, vascular injuries, and lung injuries were all improved by IGF-I + BTP-2 combination therapy.  相似文献   
3.
分析了ERDAS的LPS模块制作DOM的方法及其存在的缺点,介绍了一种结合ERDAS LPS与TerraSolid软件,快速处理超轻型飞机低空数码遥感系统获取的数码航摄影像,制作DOM的技术流程,并通过实验验证了此方法在超轻型飞机低空数码大比例尺航空正射影像图制作中的适应性.  相似文献   
4.
一种基于系数状态表的SPIHT图像编码算法   总被引:1,自引:0,他引:1       下载免费PDF全文
提出了一种新的基于系数状态表的SPIHT(LPS-SPIHT,list of p ixel stata-set partition ing in h ierarch icaltrees)图像压缩编码算法,该算法具有以下5个特点:第一,定义了一种扩展的空间方向树,使1个结点含有2×2相邻的4个系数,并将基本EZW(嵌入式小波零树)的符号定义应用于扩展树;第二,用1个廉价的系数状态表代替了SPIHT算法中的LIS(不重要集合表)、LIP(不重要像素表)、LSP(重要像素表)等3个数据表,节省了内存;第三,通过扫描系数状态表,可一次性完成对图像数据的编码,使分类过程与细化过程合二而一;第四,利用一种树指数避免了重复计算,提高了处理速度;第五,通过重新组织编码过程,省去了对大量可推知位的编码,提高了压缩效率。实践证明,与目前公认的最为有效的SPIHT算法相比,该算法不仅性能优越,而且计算简单,容易实现。  相似文献   
5.
The objective of this study was to elucidate the different mechanisms of low‐density lipoprotein (LDL) oxidation by human endothelial cells. High level of LDL stimulated human alpha‐defensin 1 (HNP‐1) expression strongly, activated myeloperoxidase (MPO), and accumulated malondialdehyde (MDA). In addition, lipopolysaccharides (LPS) had similar effect, however the cell response occurred even earlier. After 12 h of LDL co‐culture, the cells were washed and fresh LDL was added again. MPO activity and MDA generation were increased. Adding fresh LDL after the LPS co‐culture for 3 h, a similar trend, however weaker effect was observed. Culturing cells with LDL and adding various kinds of calcium antagonists at the same time did not make obvious changes to the expression of HNP‐1. In contrast, culturing cells with LPS, calcium antagonists increased HNP‐1 expression. Adding the anti‐radical drug sodium ferulate had no significant effect on oxidative function activated by LDL, but the oxidation activated by LPS was suppressed significantly and the HNP‐1 expression was not changed significantly. The endogenous irritant LDL and the exogenous irritant LPS activated human endothelial cells in different manners and HNP‐1 expression changes were involved.  相似文献   
6.
现介绍了一种适合于硬件实现的二进制算术编码器Q-Coder,并使用VHDL语言实现了该算法。在Acfive-HDL软件中进行了功能仿真,并在Quartus Ⅱ软件中完成了综合以及后仿真。综合得到的最高时钟频率为36.3MHz。  相似文献   
7.
The spark plasma sintering (SPS) was applied to prepare α-Si3 N4 ceramics of different densities with magnesia, silicon dioxide, alumina as the sintering aids. The mechanism of liquid phase sintering (LPS) wus discussed and the factors influencing the density of the prepared samples were analyzed. The dielectric constant of sintered samples was tested. The experimental results show that the density can be controlled from 2.48 g/ cm^3 to 3.09 g/ cm^3 while the content of the sintering aids and the sintering temperature alter and the dielectric constant is closely dependent on the density of obtained samples.  相似文献   
8.
早期的临床工作是了解淋巴细胞的辐射剂量与效应关系,作为初期最敏感的指标之一。对原子弹受害者的淋巴细胞也进行了远期效应的观察。实验室工作方面研究了淋巴细胞的活力、死亡率,玫瑰花结、细胞膜和DNA等分子的变化。染色体畸变,微核率及其相互关系的研讨也引起人们重视。 应用PHA、ConA、PWM、LPS分别激活淋巴细胞的各个亚群,研究其辐射效应。有关PHA激活的T淋巴细胞的辐射效应研究得较多。作者察觉PWM和ConA激活的淋巴细胞对辐射敏感,均减弱了辅助B淋巴细胞转化的作用,PHA激活的淋巴细胞受影响较轻,LPS激活的淋巴细胞变化最小。 单克隆抗体技术研究淋巴细胞亚群的进展为进一步研究淋巴细胞的辐射效应提供条件,可以了解辐射影响免疫功能的主要环节。 有的作者研究了各种病人的淋巴细胞的辐射敏感性,以了解免疫方面存在的缺陷,还可作为制定辐射治疗某些白血病方案的依据。  相似文献   
9.
Apigenin-7-glycoside (AP7Glu) with multiple biological activities is a flavonoid that is currently prescribed to treat inflammatory diseases such as upper respiratory infections. Recently, several studies have shown that its anti-inflammatory activities have been strongly linked to the inhibition of secretion of pro-inflammatory proteins, such as inducible nitric oxide synthase (iNOs) and cyclooxygenase-2 (COX-2) induced through phosphorylation nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPK) pathways. Additionally, inflammation, which can decrease the activities of antioxidative enzymes (AOEs) is also observed in these studies. At the same time, flavonoids are reported to promote the activities of heme oxygenase-1 (HO-1) decreased by LPS. The purpose of this study was to assess these theories in a series of experiments on the suppressive effects of AP7Glu based on LPS-induced nitric oxide production in RAW264.7 macrophages in vitro and acute lung injury in mice in vivo. After six hours of lipopolysaccharide (LPS) stimulation, pulmonary pathological, myeloperoxidase (MPO) activity, total polymorphonuclear leukocytes (PMN) cells, cytokines in bronchoalveolar lavage fluid (BALF) and AOEs, are all affected and changed. Meanwhile, our data revealed that AP7Glu not only did significantly inhibit the LPS-enhanced inflammatory activity in lung, but also exhibited anti-inflammatory effect through the MAPK and inhibitor NF-κB (IκB) pathways.  相似文献   
10.
目的:本研究旨在通过脂多糖(Lipopolysaccharide,LPS)诱导肝损伤小鼠考察复合醋提物(MVE)对老年小鼠炎性肝损伤的保护效果。方法:将小鼠随机分为正常对照组、MVE组、LPS组、LPS+MVE组。通过苏木精-伊红染色评估肝组织病理情况和免疫组织化学染色判断髓过氧化物酶的表达变化。同时,检测肝组织中白介素-1β、白介素-17、CXC趋化因子配体1、CXC趋化因子配体17等生化因子水平。免疫印迹法测定肝脏中Toll样受体4(Toll-like receptor 4,TLR4)和p-NF-κB p65蛋白表达量变化。结果:复合醋提物能减少中性粒细胞及炎症细胞浸润,极显著降低LPS模型小鼠肝脏谷丙转氨酶(ALT)、谷草转氨酶(AST)、活性氧(ROS)水平(P<0.01),并降低促炎因子和中性粒细胞趋化因子水平(P<0.05),降低炎症通路TLR4和p-NF-κB p65的蛋白表达水平(P<0.001)。结论:MVE能改善LPS诱导急性炎症小鼠的肝损伤,此外,MVE还能通过平衡促炎和抗炎因子水平变化、抑制TLR4-NF-κB信号通路,最终达到发挥护肝作用效果。  相似文献   
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