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排序方式: 共有232条查询结果,搜索用时 15 毫秒
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内毒素对肠黏膜微血管内皮细胞内分泌一氧化氮和内皮素的影响 总被引:1,自引:1,他引:1
目的是研究内毒素(lipopolysaccharide; LPS)导致肠黏膜微血管内皮细胞损伤的作用机制。将所培养的肠黏膜微血管内皮细胞分为空白对照组和LPS组,每组按时间分为4个亚组:3h、6h、9h、12h。空白对照组加维持培养液,LPS组加1μg/ml LPS培养液,在CO2培养箱内静置培养。结果表明,一氧化氮(NO)分泌明显升高,3h后达到高峰,随后逐渐降低,而内皮素(endothelin; ET)分泌急剧升高,9h后达到高峰,随后又开始逐渐降低,但一直保持在较高的水平。所以引起了NO和ET的升高可能是LPS导致肠黏膜微血管内皮细胞的损伤机制。 相似文献
3.
三种鳜对柱状嗜纤维菌脂多糖免疫应答的比较研究 总被引:2,自引:5,他引:2
从柱状嗜纤维菌提取菌体脂多糖作为免疫原,分别注射接种翘嘴鳜,斑鳜和大眼鳜后,检测了供试鱼血清中凝集抗体效价和血液中白细胞吞噬活性以及采用直接荧光抗体法测定了受免鳜血液中各种淋巴细胞数量的变化。结果表明,接种LPS后,3种受免鳜血清中凝集抗体效价均在第3周达到峰值,血液中蚕噬细胞的吞活性和T,B淋巴细胞样细胞的比率均在第2周最高。 相似文献
4.
Lactic Acid Inhibits NF-κB Activation by Lipopolysaccharide in Rat Intestinal Mucosa Microvascular Endothelial Cells 总被引:1,自引:0,他引:1
To investigate whether lactic acid could inhibit the LPS-activation of NF-κB p65 in rat intestinal mucosa microvascular endothelial cells (RIMMVECs), RIMMVECs, cultured in vitro, were pretreated with different concentrations of lactic acid and then exposed to lipopolysaccharide (LPS). Cells and cell culture media were then collected at different time intervals. Production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) was examined at the protein level by enzyme-linked immunosorbent assay. The influence of lactic acid on the LPS-activation of NF-κB was examined at mRNA and protein levels by real-time quantitative PCR and Western blot analysis, respectively. TNF-α and IL-6 protein levels were significantly decreased after pretreatment with lactic acid compared with cells exposed to LPS only. After pretreatment with 7.5, 5.0, and 2.5 μL mL-1 lactic acid, NF-κB mRNA levels were increased by 1.51-, 2.62- and 3.00-fold, respectively, compared with levels in control cells without LPS treatment. Western blot analysis indicated that the level of NF-κB p65 in the lactic acidpretreated group was significantly lower than that in the group treated with LPS only (positive control) and was unchanged compared with the group without LPS treatment (blank control). These results suggest that lactic acid may inhibit LPSactivation of NF-κB, leading to the down-regulation of TNF-α and IL-6. 相似文献
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试验旨在阐明前列腺素E2(prostaglandin E2,PGE2)和F2α(prostaglandin F2α,PGF2α)对体外培养的奶牛子宫内膜上皮细胞中环氧合酶-1(cyclooxygenase-1,COX-1))与环氧合酶-2(cyclooxygenase-2,COX-2)表达的影响。培养奶牛子宫内膜上皮原代细胞和传代细胞,第4代细胞以1×106个/孔接种于6孔板,以10-7mol/L PGE2和PGF2α分别预处理细胞24 h,以100 ng/mL细菌脂多糖(lipopolysaccharides,LPS)刺激细胞4、8和12 h后分别提取RNA和总蛋白质,采用实时荧光定量PCR与Western blotting等技术检测COX-1与COX-2 mRNA和蛋白质的表达量。结果表明,与对照组相比,COX-1 mRNA表达量在PGE2单独作用4、8和12 h后显著上调(P<0.05);COX-2 mRNA表达量在PGE2单独作用4和12 h后显著上调(P<0.05),PGE2单独处理使COX-1、COX-2蛋白表达量均显著上调(P<0.05)。与对照组相比,LPS刺激8和12 h时COX-1 mRNA表达量显著下调(P<0.05),LPS刺激后COX-1蛋白表达量无显著变化(P>0.05);LPS刺激后4、8和12 h时COX-2 mRNA表达量显著上调(P<0.05),LPS刺激后COX-2蛋白表达量显著上调(P<0.05)。与LPS单独处理组相比,LPS+PGE2处理组在8和12 h时COX-1和COX-2 mRNA表达量均显著上调(P<0.05),同时COX-1和COX-2蛋白表达量也显著上调(P<0.05)。PGF2α在LPS未刺激和刺激后对COX-1和COX-2 mRNA的表达无显著影响(P>0.05),仅在PGF2α单独处理8和12 h后COX-1 mRNA表达量上调(P<0.05)。两种激素联合处理与各自单独处理及LPS单独刺激相比,对COX-1和COX-2 mRNA表达具有一定的协同诱导作用。 相似文献
7.
Zengyang PEI Jinqiu WANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):139-145
Sepsis is a major cause of mortality in intensive care medicine. Propofol, an intravenous general anesthetic, has been suggested to have anti-inflammatory properties and able to prevent sepsis induced by Gram-positive and Gram-negative bacteria by down-regulating the gene expression of pro-inflammatory cytokines. However, propofol’s anti-inflammatory effects upon canine peripheral blood mononuclear cells (PBMCs) have not yet been clarified. Here, we isolate canine PBMCs and investigate the effects of propofol on the gene expressions of both lipopolysaccharide (LPS)-induced interleukin-6 (IL-6) and tumor necrosis factor (TNF)-α and upon the production of nitric oxide (NO). Through real-time quantitative PCR and the Griess reagent system, we found that non-cytotoxic levels of propofol significantly inhibited the release of NO and IL-6 and TNF-α gene expression in LPS-induced canine PBMCs. Western blotting revealed that LPS
does significantly increase the expression of inducible NO synthase (iNOS) protein in canine PBMCs, while pretreatment with propofol significantly decreases the LPS-induced iNOS protein expression. Propofol, at concentration of 25 µM and 50 µM, also significantly inhibited the LPS-induced nuclear translocation of nuclear factor (NF)-κB p65 protein in canine PBMCs. This diminished TNF-α, IL-6 and iNOS expression, and NO production was in parallel to the respective decreased NF-κB p65 protein nuclear translocation in the LPS-activated canine PBMCs pretreated with 25 µM and 50 µM propofol. This suggests that non-cytotoxic levels of propofol pretreatment can down-regulate LPS-induced inflammatory responses in canine PBMCs, possibly by inhibiting the nuclear translocation of the NF-κB p65 protein. 相似文献
8.
chTLR4及其信号通路在脂多糖致鸡淋巴细胞中的作用 总被引:1,自引:0,他引:1
Toll样受体4(Toll-like receptor 4,TLR4)是脂多糖(lipopolysaccharides,LPS)的跨膜受体,它介导了LPS诱导机体产生的多种损伤反应。本试验用LPS对鸡淋巴细胞进行6、12、24、48 h诱导,以得到IL-1β、NF-κB水平变化,为深入研究TLR4介导LPS胞内信号传递奠定了基础。结果显示,LPS诱导细胞后,IL-1β、NF-κB含量增多,均在24 h达到最大值,之后开始下降。且在12、24 h与对照组差异显著(P<0.05),在6、48 h与对照组无显著差异(P>0.05)。 相似文献
9.
仿刺参cytb和β-actin基因表达稳定性比较 总被引:1,自引:0,他引:1
基因表达分析需要采用内参基因来校正目的基因的表达量。采用半定量RT-PCR的方法分析了cytb和β-actin基因在仿刺参(Apostichopus japonicus)未受精卵、受精卵、多细胞期、囊胚期、原肠期、小耳状幼体、中耳状幼体、大耳状幼体、樽型幼体、五触手幼体、稚参11个发育阶段和幼参的体壁、体腔细胞、肠道和呼吸树中的表达情况。结果表明:cytb在不同发育阶段和不同组织中稳定表达;β-actin基因在稚参之前不同发育阶段中表达水平有显著差异,在幼参的体壁、肠道和呼吸树中稳定表达。此外,cytb在lipopolysaccgarides (LPS)刺激前后的原肠胚、小耳状幼体、中耳状幼体、大耳状幼体、樽型幼体、稚参和幼参四种组织中表达量无显著差异;β-actin基因在LPS刺激前后的幼参体腔细胞、肠道和呼吸树中表达量无显著差异。本研究为仿刺参功能基因表达分析中,cytb与β-actin基因作为内参基因的可行性提供了依据。 相似文献
10.
试验旨在研究不同浓度的天门冬多糖(ASP),在ConA或LPS的协同刺激下对猪脾淋巴细胞体外增殖的影响。猪脾淋巴细胞体外培养体系中加入不同浓度的天门冬多糖使其终浓度为400、200、100、50、25、12.5μg/ml,在ConA(5μg/ml)或者LPS(10μg/ml)的协同刺激作用下,细胞培养24、48、72 h时,观察猪脾淋巴细胞增殖情况。结果表明,天门冬多糖及其协同ConA或LPS能显著或极显著的促进猪脾淋巴细胞体外增殖(P<0.05或P<0.01)。 相似文献