首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   91篇
  免费   2篇
  国内免费   2篇
林业   7篇
农学   4篇
基础科学   1篇
  2篇
综合类   38篇
农作物   7篇
畜牧兽医   10篇
园艺   25篇
植物保护   1篇
  2021年   1篇
  2020年   6篇
  2019年   2篇
  2018年   7篇
  2017年   5篇
  2016年   2篇
  2015年   4篇
  2014年   6篇
  2013年   5篇
  2012年   13篇
  2011年   11篇
  2010年   4篇
  2009年   4篇
  2008年   6篇
  2007年   4篇
  2006年   4篇
  2005年   5篇
  2004年   1篇
  2003年   1篇
  2002年   2篇
  2001年   1篇
  1999年   1篇
排序方式: 共有95条查询结果,搜索用时 15 毫秒
1.
GAO Meng  HUANG Juan 《园艺学报》2020,36(7):1161-1169
AIM To investigate the protective effect of resveratrol (Res) on cortical neurons in rat bacterial meningitis (BM) model. METHODS Group B hemolytic Streptococcus was injected via the posterior cistern to establish a BM model. Resveratrol was administered intranasally and microRNA-223-3p (miR-223-3p) antagomir was administered by intracerebroventricular injection. HE staining was used to observe the pathological changes of the brain tissue. Loeffler scoring method was used to evaluate the neurobehavioral functions. TUNEL staining was used to detect neuronal apoptosis. The expression of interleukin-1β (IL-1β), IL-18, glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule 1 (Iba1) was detected by immunofluorescence staining. The protein levels of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), cleaved caspase-1, IL-1β and IL-18 were determined by Western blot. The expression level of miR-223-3p was detected by RT-qPCR. Online software TargetScan was used to search for the complementary nucleotide sequences between miR-223-3p and NLRP3 mRNA. RESULTS Compared with sham group, the thickness of meninges in BM model was increased, the neurological score was decreased (P<0.05), and the number of TUNEL positive neurons was increased significantly (P<0.05). Astrocytes and microglia were activated, the fluorescence intensity of IL-1β and IL-18 was increased (P<0.05), and the expression levels of NLRP3, cleaved caspase-1, IL-1β, IL-18 and miR-223-3p were increased (P<0.05). Compared with BM group, after treatment with resveratrol, the neurological score was increased (P<0.05), the number of TUNEL positive neurons was decreased significantly (P<0.05), and the inflammatory response of astrocytes and microglia was suppressed. The fluorescence intensity of IL-1β and IL-18 was decreased (P<0.05), the protein levels of NLRP3, cleaved caspase-1, IL-1β and IL-18 were decreased (P<0.05), and the expression level of miR-223-3p was increased (P<0.05). A nucleotide sequence in the 3'-UTR of NLRP3 mRNA might be targeted by miR-223-3p. In the brain of rat BM model, compared with antagomir control group, the expression of NLRP3 was increased in miR-223-3p antagomir group with resveratrol treatment (P<0.05). CONCLUSION Resveratrol may reduce the inflammatory death of cortical neurons in BM model of infant rats through miR-223-3p/NLRP3 pathway, thus playing a protective role for the neurons.  相似文献   
2.
以1a生北丰(Vitis thunbergii×V.vinifera)葡萄盆栽结果树为试材,在果实始熟期采用紫外线C(Ultraviolet C,UV-C)辐射结合韧皮部环剥的方法,研究了UV-C辐射对葡萄叶片和邻近果穗果实白藜芦醇(Resveratrol,Res)及其糖苷质量分数的影响。结果表明,UV-C辐射诱导葡萄果实Res合成积累的敏感性低于叶片,辐射葡萄叶片对邻近果穗上果皮Res的影响远远小于UV-C直接辐射葡萄果穗,且辐射诱导葡萄果皮中Res质量分数与叶片中Res质量分数存在着一定的相关性。当叶片位于果穗下方时,叶片中反式白藜芦醇(trans-Resveratrol,trans-Res)、反式白藜芦醇苷(trans-Piceid,trans-PD)和顺式白藜芦醇苷(cis-Piceid,cis-PD)质量分数表现出环剥处理显著高于不环剥处理,然而果皮中的结果正好相反。当叶片位于果穗上方时,果皮中trans-Res、trans-PD和cis-PD质量分数表现出不环剥处理显著高于环剥处理,暗示葡萄Res可能存在韧皮部运输途径,且运输方向是双向的。此外,UV-C直接辐射葡萄果穗处理果皮trans-Res和cis-PD质量分数显著高于对照和UV-C辐射葡萄叶片处理。种子中仅检测到trans-Res,且仅环剥处理和辐射下方叶片不环剥处理显著高于对照。  相似文献   
3.
芪合酶基因的克隆及其酵母表达载体的构建   总被引:1,自引:0,他引:1       下载免费PDF全文
应用基因工程技术将从中国野生属葡萄种高抗白粉病的华东葡萄白河-35-1中分离出的芪合酶基因cDNA片段(Stilbene synthase,STS)进行PCR扩增;把回收的目的基因PCR产物定向插入克隆载体pGEM-TEasy中进行测序与序列分析;采用定向克隆的方法将芪合酶基因克隆到大肠杆菌-酵母菌穿梭型酿酒酵母表达载体pYES6/CT上,转化大肠杆菌,提取阳性重组质粒转化酿酒酵母菌(Saccharomyces cerevisiae)菌株INVScl,酵母菌落PCR电泳结果显示,在约1200bp处有一条亮带,证明芪合酶基因酵母表达载体构建成功,为后期工作的开展奠定了基础,并为开发一种含有白藜芦醇生物活性成分的酵母微生态制剂提供了重要的实验素材。  相似文献   
4.
研究采用酶解法从葡萄酒泥中提取白藜芦醇,探索其最佳提取工艺,在单因素试验的基础上,以酶浓度、酶解温度、酶解时间为因素进行正交试验。结果表明:酶浓度、酶解时间对白藜芦醇的提取效果有显著影响,最佳提取工艺条件为p H值4.0,酶浓度1.5mg/g,酶解温度40℃,酶解时间75min,在此条件下白藜芦醇提取量为80.2μg/g。  相似文献   
5.
AIM:To investigate the inhibitory effects of resveratrol on chondrosarcoma and the relation with mitochondrial and PI3K/Akt pathways. METHODS:Chondrosarcoma SW1353 cells were treated with resveratrol at concentrations of 25, 50 and 100 μmol/L for the time intervals of 24 h, 48 h and 72 h. The viability and apoptosis of the SW1353 cells in the presence or absence of resveratrol were analyzed by CCK8 assay and Hoechst 33258 staining, respectively. The protein levels of Bcl-2, Bax, activated caspase-3, Akt and p-Akt were detected by Western blotting. The cell migration ability was determined by wound scratch assay. RESULTS:Exposure of the cells to resveratrol resulted in a decrease in the cell viability in a dose- and time-dependent manner (P<0.05). visible nuclei with apoptotic characteristics in resveratrol group were observed. The protein levels of activated caspase-3 and Bax were increased, and Bcl-2 and p-Akt were decreased compared with control group. The total Akt were not significantly changed. Resveratrol also significantly reduced the migration of tumor cells. CONCLUSION:Resveratrol induces apoptosis of chondrosarcoma, which plays a role of part through mitochondrial and PI3K/Akt signaling pathways.  相似文献   
6.
花生种子白藜露醇的诱导 与抗黄曲霉侵染关系的研究   总被引:3,自引:1,他引:3  
通过比较抗—感花生品种受黄曲霉菌侵染后,种子诱导白藜露醇的差异,探讨白藜露醇诱导与花生种子 抗黄曲霉侵染关系。结果表明:受黄曲霉侵染后,花生种子白藜露醇诱导的速度与抗性有关。抗性品种在受侵染 后3d种子内的白藜露醇大量累积并达到峰值,含量提高30倍;而感病品种则在受侵染后4d才达到此峰值。放线 菌素酮和放线菌素D处理后接种试验表明,种子本身含有合成白藜露醇的mRNA,当受外源黄曲霉菌侵染时能激 活与合成白藜露醇相关酶的活性,合成大量白藜露醇。  相似文献   
7.
High insulin concentrations are a common clinical feature of equine metabolic syndrome (EMS) and insulin dysregulation. Hyperinsulinemia can induce laminitis, so reduction of insulin concentrations in response to an oral challenge should decrease risk. In human studies, diets containing a polyphenol (resveratrol) led to improvements in insulin sensitivity. In rodents, the addition of leucine to a resveratrol supplement caused a decrease in the amount of resveratrol needed to achieve a clinical effect. We hypothesize a supplementation with a low dose of a synergistic polyphenol and amino acid blend including leucine (SPB+L) would improve metabolic health in EMS/insulin dysregulated horses. Fifteen EMS/ID horses received a high or low dose of SPB+ L daily for 6 weeks. Insulin during an oral sugar test (OST), body condition score, weight, baseline high-molecular-weight (HMW) adiponectin, triglycerides, nonesterified fatty acids, and tumor necrosis factor alpha were assessed before supplementation (PRE) and after supplementation (POST) via paired Student’s t-tests and a repeated-measures mixed-model analysis of variance (significant at P < .05). There were no differences between doses. Horses in the POST group weighed significantly less, had significantly higher baseline HMW adiponectin concentrations, and had significantly lower insulin concentrations at 60- and 75-minute time points (P < .05). Insulin concentrations of the horsesin the POST group, but not in the PRE group, were lower and similar to results from the study conducted three years before the present study (PRIOR) for 0- and 60-minute time points (P < .002). An increased HMW adiponectin level supports increasing insulin sensitivity after supplementation. These results suggest that SPB + L supplementation at either dose leads to improvements in the clinical manifestations of EMS/insulin dysregulation, potentially reducing laminitis risk.  相似文献   
8.
AIM: To investigate the possible mechanism of resveratrol (Res) on tumor necrosis factor-α (TNF-α)-induced monocyte chemoattractant protein-1 (MCP-1) expression in primary rat pulmonary artery endothelial cells (RPAECs).METHODS: RPAECs were randomly divided into 4 groups:control group, solvent (1% DMSO) group, TNF-α group and Res group. Each group was divided into 1 h, 4 h and 8 h subgroups (n=6 per time point). The TNF-α+C1142 (a rodent chimeric mAb that neutralizes rat MCP-1) group was set up at the 8 h time point. At each time point, the protein and mRNA expression of MCP-1 was measured by Western blot and real-time PCR.RESULTS: Pretreatment of the RPAECs with C1142 significantly down-regulated the expression of MCP-1 (P<0.05). The protein and mRNA expression of MCP-1 was markedly increased in TNF-α group (P<0.05). Notably, incubation with Res down-re-gulated the protein and mRNA expression of MCP-1, which was significantly lower than that in TNF-α group (P<0.05).CONCLUSION: MCP-1 was involved in the process of TNF-α-induced injury of RPAECs. Res down-regulates the expression of MCP-1 in RPAECs, thus attenuating cell injury.  相似文献   
9.
葡萄属植物白藜芦醇研究进展   总被引:35,自引:1,他引:35  
根据有关文献分别从白藜芦醇穴Res雪的发现、化学结构、物理特性、对葡萄属植物及人体健康的作用、作用机理方面作了简要概述,总结了其诱导、取样、测定方法,在葡萄植物体内的分布、动态变化、器官之间含量的相关性,葡萄属植物种间、品种间及葡萄加工品之间的含量差异,并介绍了白藜芦醇的生物合成、几种合成酶,影响代谢的内部、外部因素,对白藜芦醇的研究意义及应用前景也进行了讨论。  相似文献   
10.
白藜芦醇对HA-VSMC细胞膜电位和钙离子的影响   总被引:1,自引:0,他引:1  
[目的]研究白藜芦醇对人主动脉血管平滑肌细胞(T/G HA-VSMC)膜电位和游离钙浓度的影响。[方法]用荧光染料DiBAC4(3)和Fluo-3-AM分别标记细胞,在流式细胞仪上分别测定细胞膜电位及胞内游离钙浓度的变化。[结果]给予Res后,HA-VSMC膜电位去极化,胞内游离钙浓度升高。[结论]Res可去极化HA-VSMC细胞膜电位,促进钙内流。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号