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981.
橄榄苦苷是一种广泛存在于木犀科植物中的天然抗氧化剂,大量的研究结果显示其具有抗氧化、抗炎、抗癌、抗病毒、保护心脏、保护皮肤、保护神经系统等生物活性,该研究收集了橄榄苦苷和富含橄榄苦苷的提取物相关研究论文,对其化学结构与来源、生物活性及作用机制、安全性方面的研究进展进行了简要综述,以期为橄榄苦苷的进一步研究提供参考依据。  相似文献   
982.
交叉保护防治柑橘衰退病研究进展   总被引:1,自引:0,他引:1  
周彦 《园艺学报》2014,41(9):1793-1801
柑橘衰退病毒引起的茎陷点型和速衰型衰退病对世界柑橘产业造成了严重损失。目前交叉保护是防治茎陷点型衰退病最有效的方法,也用于酸橙砧木速衰型衰退病的防治。从各国防治经验、弱毒株筛选方法、防治机理等方面对交叉保护防治柑橘衰退病的最新研究进展作出综述,同时就现有交叉保护防治技术的不足和解决途径进行讨论和展望,旨在为更好地防治柑橘衰退病提供借鉴。  相似文献   
983.
AIM: To investigate the effect of silencing cell division cycle 25a (CDC25a) gene on the proliferation of human hepatoma HepG2 cells. METHODS: CDC25agene in human hepatoma HepG2 cells was silenced by RNA interference. Real-time PCR was applied to detect the expression of CDC25a, cyclin E and CDK2 at mRNA levels in the HepG2 cells. Western blotting was applied to detect the expression of CDC25a at protein level. In addition, MTT assay, Giemsa staining and flow cytometry were used to measure the proliferation of human hepatoma HepG2 cells. RESULTS: The expression of CDC25a at mRNA and protein levels in RNA silence group was lower than those in negative control group and normal control group (P<0.05). The mRNA expression of cyclin E and CDK2 in silence group was lower than that in negative control group and normal control group (P<0.05). The cell proliferation in silence group was lower than that in negative control group and normal control group (P<0.05). The results of flow cytometry revealed that the cells in silence group were blocked in G1 phase. CONCLUSION: Infection of LV-CDC25a-RNAi recombinant to the HepG2 cells effectively inhibits the CDC25agene expression and the proliferation of human hepatoma cells, and arrests the cells in G1 phase, suggesting that CDC25agene may be a key target for the treatment of liver cancer.  相似文献   
984.
AIM:To investigate the effect of Sini decoction (SND) on vascular stenosis and the expression of transfoming growth factor-β1 (TGF-β1) in iliac artery balloon injured rabbits. METHODS:24 male New Zealand albino rabbits were divided into three groups:control group, model group and SND treatment group. The iliac arteries were injured by balloon in model and SND groups. Four weeks later, serum TGF-β1 level was assayed by ELISA. Endothelial hyperplasia, TGF-β1 protein and mRNA expression were observed in injured iliac artery. RESULTS:Light microscope showed that the vascular lumina were narrower, intima was thicker in model group control and SND treatment group. The serum TGF-β1 level was lower in control than model group and SND treatment group, and the serum TGF-β1 level in SND treatment group was lower than that in model group. Immunohistochemistry and RT-PCR results showed that TGF-β1 protein and mRNA expression was lower in rabbit iliac artery of control group than that in model group and SND treatment group, and the expression of TGF-β1 protein and mRNA decreased significantly in SND treatment group compared with model group. CONCLUSION:SND could lessen intimal hyperplasia and vascular stenosis in balloon injured iliac artery, which might be related to decrease in TGF-β1 protein and gene expression in iliac artery.   相似文献   
985.
986.
AIM: To investigate the effect of apyrase on the experimental silicosis. METHODS: C57BL/6 male mice were randomly divided into control group, silica treatment group, silica+apyrase group and silica+NS group. A mouse model of lung fibrosis was induced by crystalline silica particles (50 mg/kg, via oropharyngeal instillation), and were sacrificed at 3 h, 7 d, 14 d and 28 d. Apyrase was delivered by oropharyngeal aspiration at the same time and 4 h after silica challenge. The lung indexes were calculated and the concentration of ATP was detected by bioluminescent assay. The mRNA expression levels of collagen type Ⅰ(Col Ⅰ), collagen type Ⅲ (Col Ⅲ) and transforming growth factor β1 (TGF-β1) were examined by real-time PCR. The protein levels of TGF-β1 in bronchoalveolar lavage fluid were measured by ELISA. RESULTS: The elevated lung index and collagen levels showed that silicosis model was established successfully. Compared with silica group, apyrase treatment significantly alleviated silica-induced inflammation, reduced inflammation score on day 7, and decreased the lung index, collagen volume fraction and the mRNA expression of Col Ⅰand Col Ⅲ on day 28. Treatment with apyrase effectively down-regulated the mRNA levels of TGF-β1 in the lung tissues and TGF-β1 protein levels in bronchoalveolar lavage fluid on day 7.CONCLUSION: Apyrase attenuates the pulmonary inflammation and fibrosis of silicosis, which may be related with down-regulation of ATP and TGF-β1 in the lung tissues.  相似文献   
987.
辣椒在不同温度条件下萌发特性的研究   总被引:2,自引:0,他引:2  
用5种温度(15℃、20℃、25℃、30℃、35℃)处理(以25℃处理为对照),研究各温度下“湘辣妹”尖椒品种种子的发芽率、发芽势及发芽指数的变化规律,为生产应用提供依据。结果表明:“湘辣妹”尖椒品种种子的发芽适宜温度范围为25-30℃,最佳发芽温度为25℃。  相似文献   
988.
通过比较熊蜂和蜜蜂对大棚栽培草莓的授粉效果试验得出,与蜜蜂相比,熊蜂的出巢时间早,工作时间长,趋光性差,撞棚膜现象发生少,且饲喂简单,饲料投入量少。采用熊蜂授粉的草莓平均产量可达16708.5kg/hm2,比采用蜜蜂授粉的棚增产35.0%;熊蜂授粉草莓单果质量为8.28g,比采用蜜蜂授粉的增加58.6%,差异显著;熊蜂授粉的草莓糖度为11.68%,蜜蜂授粉的草莓糖度为11.29%,差异不显著;熊蜂授粉的草莓畸形果率平均比蜜蜂授粉的低67.9%,差异显著。试验结果进一步说明了熊蜂比蜜蜂更适合用来进行设施草莓授粉。  相似文献   
989.
周建  张红倩 《北方园艺》2011,(24):72-75
通过在晴天和阴天2组对比试验,研究了木槿、栾树与杨树3种不同植物群落对环境中空气温度、空气湿度、光照强度、地温4个因子的影响作用.结果表明:在阴天类型中,3种植物群落均能有效地降低气温、地温与光照强度,从而提高空气湿度,且调节效果为:杨树>栾树>木槿;在晴天类型中,栾树与杨树群落的调节效果与阴天相似,其中杨树的调节效果大于栾树.此外,每种植物群落在晴天时对环境因子的调节效果大于阴天时的调节效果.  相似文献   
990.
柳糖一号(原名桂柳01-07)是柳州市农业科学研究所以F172为母本,CP67/412为父本采用有性杂交经过10年的常规选育而成,具有早熟、高产高糖等优良特性。2007—2009年在广西甘蔗品种区域试验及生产试验中,柳糖一号的11月至1月份的平均甘蔗糖分分别为15.53%、15.09%,比对照种ROC16的糖分分别高0.60%、0.68%;柳糖一号的产蔗量分别为88085kg/hm2、95865kg/hm2,与对照种ROC16相当;柳糖一号的含糖量分别为13720kg/hm2,14460kg/hm2,比对照种ROC16分别增产4.33%、5.82%。柳糖一号于2010年5月通过广西农作物品种审定委员会审定。  相似文献   
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