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81.

Background

Canine osteosarcoma (OS) is associated with localized pain as a result of tissue injury from tumor infiltration and peritumoral inflammation. Malignant bone pain is caused by stimulation of peripheral pain receptors, termed nociceptors, which reside in the localized tumor microenvironment, including the periosteal and intramedullary bone cavities. Several nociceptive ligands have been determined to participate directly or indirectly in generating bone pain associated with diverse skeletal abnormalities.

Hypothesis

Canine OS cells actively produce nociceptive ligands with the capacity to directly or indirectly activate peripheral pain receptors residing in the bone tumor microenvironment.

Animals

Ten dogs with appendicular OS.

Methods

Expression of nerve growth factor, endothelin‐1, and microsomal prostaglandin E synthase‐1 was characterized in OS cell lines and naturally occurring OS samples. In 10 dogs with OS, circulating concentrations of nociceptive ligands were quantified and correlated with subjective pain scores and tumor volume in patients treated with standardized palliative therapies.

Results

Canine OS cells express and secrete nerve growth factor, endothelin‐1, and prostaglandin E2. Naturally occurring OS samples uniformly express nociceptive ligands. In a subset of OS‐bearing dogs, circulating nociceptive ligand concentrations were detectable but failed to correlate with pain status. Localized foci of nerve terminal proliferation were identified in a minority of primary bone tumor samples.

Conclusions and Clinical Importance

Canine OS cells express nociceptive ligands, potentially permitting active participation of OS cells in the generation of malignant bone pain. Specific inhibitors of nociceptive ligand signaling pathways might improve pain control in dogs with OS.  相似文献   
82.
选用24只3月龄、体质量(13.0±l.0)kg的雄性波尔山羊,随机分为4组,每组6只。试验期为60d。其中Ⅰ组为对照组,饲料添加微量元素;Ⅱ组(低剂量组)、Ⅲ组(中剂量组)、Ⅳ组(高剂量组)分别按0.5、1.0、2.omL/kg肌肉注射“生命元”。试验前1d、试验后15、30、45、60d分别测定波尔山羊的采食量、日增重、血液生理生化指标以及血清IgG、IgM、IgA、IL-2、IL-6的含量。结果表明:(1)试验期0-60d内,与Ⅰ组波尔山羊相比,Ⅲ组能显著(P〈0.05)提高成产性能。(2)60d时,与Ⅰ组相比,Ⅱ组、Ⅲ组和Ⅳ组均能显著(P〈0.05)提高波尔山羊红细胞数和血红蛋白含量。(3)与Ⅰ组相比,“生命元”能明显改善波尔山羊基础代谢水平,提高波尔山羊血糖、总蛋白含量,但Ⅲ组能显著(P〈0.05)降低血清尿素氮含量(45d)、降低总胆固醇含量(60d)。(4)试验组波尔山羊血清IgG、IgM、IgA含量在各个时期内显著或极显著高于对照组(P〈0.05或P〈0.01)。(5)试验组波尔山羊血清中IL-2含量均高于对照组,但差异不显著;试验组在注射后15d血清IL-6含量显著高于对照组。结论:复方微量元素注射液“生命元”能提高波尔山羊生产性能、红细胞数和血红蛋白含量,改善糖、蛋白质和脂肪代谢,并能提高波尔山羊血清中IgG、IgM、IgA及IL-2、IL-6的含量。其中以1.0mL/kg肌肉注射效果最好。  相似文献   
83.
多糖类物质是具有提高免疫力、抗病毒、抗肿瘤、抗氧化、抗炎症等广泛生理作用的生物活性成分。近年来,甘草多糖的作用受到研究人员的广泛关注,甘草多糖可以通过调节机体固有免疫、体液免疫、细胞免疫和细胞因子来增强机体免疫力,还可以通过调控机体氧化平衡、MAPK信号通路和NF-κB核因子发挥有效的抗炎作用,并具有防治骨关节炎和治疗胃炎的作用。重点阐述甘草多糖的免疫调节和抗炎作用机制,旨在为甘草多糖的进一步研究提供理论基础,并为甘草多糖的临床应用提供有价值的实践指导。  相似文献   
84.
为明确PYY对巨噬细胞炎性细胞因子分泌的调节作用,本试验分离培养健康小鼠腹腔巨噬细胞,不同浓度PYY预处理后,以LPS刺激。ELISA方法检测细胞培养上清中TNF-α、IL-6含量,半定量PCR方法检测细胞中TNF-α、IL-6mRNA表达变化。结果显示:高浓度的PYY1-36(10-9-10-7 mol/L)和PYY3-36(10-8-10-7 mol/L)对LPS诱导小鼠腹腔巨噬细胞TNF-α分泌具有显著抑制作用(P〈0.05);PYY1-36对LPS诱导小鼠腹腔巨噬细胞IL-6分泌无明显作用(P〉0.05);不同浓度PYY3-36(10-11-10-7 mol/L)对LPS诱导小鼠腹腔巨噬细胞IL-6分泌均具有显著抑制作用(P〈0.05)。表明PYY对LPS诱导小鼠腹腔巨噬细胞炎性细胞因子TNF-α及IL-6的分泌具有一定的抑制作用,提示PYY可能通过抑制炎性细胞因子的分泌而抑制炎症性疾病的发生发展。  相似文献   
85.
本试验旨在研究聚乙二醇(PEG)修饰猪胰高血糖素样肽-2(pGLP-2)对结肠炎小鼠肠道紧密连接蛋白和炎性因子基因表达的影响.试验选取24只BALB/C小鼠,随机分为4组,葡聚糖硫酸钠(DSS)组小鼠饮用3% DSS建立小鼠结肠炎模型,DSS +pGLP-2组和DSS+ PEG-pGLP-2组饮用3% DSS且在试验第8天腹腔分别注射pGLP-2和PEG-pGLP-2,饮水组小鼠正常饮水.试验期10 d.结果表明:与饮水组相比,DSS组小鼠结肠紧密连接闭锁小带基因(ZO-1)的mRNA相对表达量极显著降低(P<0.01);与DSS组相比,注射pGLP-2对ZO-1的mRNA相对表达量没有改善(P>0.05),而注射PEG-pGLP-2可极显著增加ZO-1的mRNA相对表达量(P<0.01).与饮水组相比,DSS组小鼠结肠白细胞介素-6(IL-6)、白细胞介素-10(IL-10)和干扰素-γ基因(INF-γ)的mRNA相对表达量极显著增加(P<0.01);与DSS组相比,注射pGLP-2和PEG-pGLP-2可极显著降低IL-6、IL-10和IFN-γ的mRNA相对表达量(P<0.01).结果提示,PEG-pGLP-2通过增加肠道紧密连接蛋白的表达、降低结肠炎小鼠炎性细胞因子的表达抑制其炎性病变,且作用效果优于pGLP-2.  相似文献   
86.
To investigate the role of polysaccharide from Acanthopanax senticosus (ASPS) on lipopolysaccharide (LPS)‐induced intestinal injury, mice in three treatments were administrated orally with or without ASPS (300 mg/kg body weight) for 14 days, followed by challenge with LPS or saline. At 4 h post‐injection, blood and intestinal samples of six mice / treatment were collected. The results showed ASPS ameliorated LPS‐induced intestinal morphological deterioration, proven by improved villus height (P < 0.05) and villus height : crypt depth ratio (P < 0.05). ASPS also elevated the mucosal barrier of LPS‐challenged mice, supported by reduced plasma diamine oxidase (DAO) activity (P < 0.05) and L‐lactate (P < 0.05), increased mucosal DAO activity (P < 0.05) as well as enhanced intestinal tight junction proteins expression involving occludin‐1 (P < 0.05) and zonula occludens‐1 (P < 0.05). In addition, ASPS decreased LPS‐induced secretion of inflammatory mediators, including tumor necrosis factor (TNF)‐α (P < 0.05) and prostaglandin E2 (P < 0.05). Also, ASPS down‐regulated messenger RNA expression of toll‐like receptor 4 (TLR4) and its downstream signals, including myeloid differentiation factor 88 (P < 0.05), TNF‐α receptor‐associated factor 6 (P < 0.05), as well as nuclear factor (NF)‐κB p65 (P < 0.05) and its protein expression. These findings suggest that ASPS improves intestinal integrity under inflammation conditions connected with inhibiting TLR4/NF‐κB signaling pathways.  相似文献   
87.
The pathogenesis of canine atopy has not been established completely. Recent studies have shown that tumour necrosis factor alpha and Interleukin‐6 play a role in allergic reactions in humans and mice. Pentoxifylline (PTX) suppresses synthesis of these cytokines and may be a useful therapy for modulating the symptoms of canine atopy. The objectives of this study were to investigate the effects of PTX (10mg kg?1 twice daily for 4 weeks) on clinical signs (erythema and pruritus) and intradermal skin test reactivity in atopic dogs (n = 10). The study was a double‐blinded, placebo controlled, crossover clinical trial with a washout period of 2 weeks between treatments. Clinical signs were evaluated and scored by the investigator and owners. During PTX treatment, scores of pruritus and erythema decreased significantly. PTX did not affect intradermal skin test reactivity to house dust mite at 15 min (allergen of reference for this study).  相似文献   
88.
试验旨在研究大肠杆菌(E.coli)对奶牛子宫内膜上皮细胞(bovine endometrial epithelial cells,BEECs)的体外炎性损伤,探究大肠杆菌引发炎性反应的最佳浓度、作用时间及机制。首先,用不同浓度的大肠杆菌(5×104、5×105、1×106、2.5×106、5×106 CFU/mL)诱导刺激细胞3、6和9 h,通过倒置显微镜观察细胞形态、CCK-8法测D450 nm值,检测大肠杆菌对细胞活性的影响;其次,用不同浓度的大肠杆菌(5×104、5×105 CFU/mL)处理细胞3、6和9 h,用ELISA方法检测细胞上清液中白介素-1β(IL-1β)、IL-6、IL-8和肿瘤坏死因子-α(TNF-α)的分泌量;最后,用不同浓度的大肠杆菌(5×104、5×105 CFU/mL)处理细胞6和9 h,用Western blotting检测核因子κB抑制蛋白α(IκBα)和p65蛋白的磷酸化水平。结果显示,与对照组相比,大肠杆菌感染细胞9 h后,1×106、2.5×106和5×106 CFU/mL大肠杆菌组细胞活性均极显著降低(P<0.01),5×105 CFU/mL大肠杆菌组显著降低(P<0.05);大肠杆菌感染细胞9 h后,5×105 CFU/mL大肠杆菌组IL-1β、IL-6、IL-8和TNF-α极显著升高(P<0.01);大肠杆菌感染细胞6 h后,5×105 CFU/mL大肠杆菌组IκBα、p65蛋白磷酸化水平和IL-6均极显著升高(P<0.01),5×104 CFU/mL大肠杆菌组IκBα和p65蛋白磷酸化水平显著升高(P<0.05)。结果表明,大肠杆菌可以刺激奶牛子宫内膜上皮细胞产生炎性反应,且当细胞与5×105 CFU/mL大肠杆菌作用6 h或与5×104 CFU/mL大肠杆菌作用9 h为最佳。  相似文献   
89.
BackgroundPseudorabies virus (PRV) infection leads to high mortality in swine. Despite extensive efforts, effective treatments against PRV infection are limited. Furthermore, the inflammatory response induced by PRV strain GXLB-2013 is unclear.ObjectivesOur study aimed to investigate the inflammatory response induced by PRV strain GXLB-2013, establish an inflammation model to elucidate the pathogenesis of PRV infection further, and develop effective drugs against PRV infection.MethodsKunming mice were infected intramuscularly with medium, LPS, and different doses of PRV-GXLB-2013. Viral spread and histopathological damage to brain, spleen, and lung were determined at 7 days post-infection (dpi). Immune organ indices, levels of reactive oxygen species (ROS), nitric oxide (NO), and inflammatory cytokines, as well as levels of activity of COX-2 and iNOS were determined at 4, 7, and 14 dpi.ResultsAt 105–106 TCID50 PRV produced obviously neurological symptoms and 100% mortality in mice. Viral antigens were detectable in kidney, heart, lung, liver, spleen, and brain. In addition, inflammatory injuries were apparent in brain, spleen, and lung of PRV-infected mice. Moreover, PRV induced increases in immune organ indices, ROS and NO levels, activity of COX-2 and iNOS, and the content of key pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ and MCP-1. Among the tested doses, 102 TCID50 of PRV produced a significant inflammatory mediator increase.ConclusionsAn inflammatory model induced by PRV infection was established in mice, and 102 TCID50 PRV was considered as the best concentration for the establishment of the model.  相似文献   
90.
This study was carried out to evaluate the effects of induced urolithiasis by high dietary calcium (Ca) or protein levels on biochemical analyte levels, redox status, selected inflammatory cytokines and histopathology in chickens. A total of 90 one-day-old white Hy-Line chicks were fed basal control diets containing 20% crude protein (CP) and 1% Ca until they reached 44 days of age. After that, the birds were divided into three groups (30 birds per group). All management factors (light, temperature, ventilation, stock density and diet) were identical among the three groups throughout the study except for the dietary Ca and protein percentages. Group I was fed a control diet containing 20% CP and 1% Ca, group II was fed a high-Ca diet containing 5% Ca, and group III was fed a high-protein diet containing 25% CP. Our findings clearly demonstrated that dietary imbalance (caused by high-Ca or high-CP levels) per se in chickens was physiologically harmful, as it was accompanied by post-mortem lesions; biochemical, redox status and histopathological alterations; and upregulation of inflammatory cytokines (interleukin (IL)-1β and IL-6). In particular, the birds fed the high-Ca diet clearly exhibited the most obvious alterations in most of the endpoints. In conclusion, this study constitutes the first extensive investigation of the effects of high-Ca or high-protein diets induced urolithiasis on growth performance, redox status, inflammatory cytokine levels and pathological characterization in chickens.  相似文献   
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