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21.
Viruses, and in particular the deformed wing virus (DWV), are considered as one of the main antagonists of honey bee health. The ‘suppressed in ovo virus infection’ trait (SOV) described for the first time that control of a virus infection can be achieved from genetically inherited traits and that the virus state of the eggs is indicative for this. This research aims to explore the effect of the SOV trait on DWV infections in queens descending from both SOV-positive (QDS+) and SOV-negative (QDS–) queens. Twenty QDS+ and QDS– were reared from each time four queens in the same starter–finisher colony. From each queen the head, thorax, ovaries, spermatheca, guts and eviscerated abdomen were dissected and screened for the presence of the DWV-A and DWV-B genotype using qRT-PCR. Queens descending from SOV-positive queens showed significant lower infection loads for DWV-A and DWV-B as well as a lower number of infected tissues for DWV-A. Surprisingly, differences were less expressed in the reproductive tissues, the ovaries and spermatheca. These results confirm that selection on the SOV trait is associated with increased virus resistance across viral genotypes and that this selection drives DWV towards an increased tissue specificity for the reproductive tissues. Further research is needed to explore the mechanisms underlying the interaction between the antiviral response and DWV.  相似文献   
22.
李娟  张松  秦雪梅  李震宇 《中草药》2015,46(20):3009-3016
目的探究款冬花蜜炙的科学内涵。方法基于NMR代谢组学技术对款冬花生品和蜜炙品进行分析,采用主成分分析(PCA)、正交偏最小二乘法辨别分析(OPLS-DA)以及单变量分析对款冬花蜜炙前后化学成分进行比较。结果款冬花的代谢指纹图谱共指认出40种代谢物,多元统计结果显示款冬花蜜炙品和生品之间存在显著差异,蜜炙后初级代谢产物1-O-乙基-β-D-葡萄糖苷、β-葡萄糖、蔗糖、α-葡萄糖的量明显升高,缬氨酸、天冬氨酸、苏氨酸的量降低;次级代谢产物款冬酮、芦丁的量升高,绿原酸、咖啡酸等有机酸的量有所降低。结论从整体化学组成上比较了款冬花生品与蜜炙品的差异,为其蜜炙的科学内涵研究奠定了基础。  相似文献   
23.
Honey bees (Apis mellifera L.) play a vital role in agriculture as pollinators, and serve as model organisms of social behaviour and immunity. The lack of both immortalized cell lines and methods to introduce recombinant DNA reliably into primary cells hinders cellular and molecular studies in this organism. We hereby demonstrate the expression of a GFP gene delivered by lentivirus transduction to cultured embryonic cells. The success of this approach indicates that viral transduction could be used to deliver constitutively active oncogenes in order to immortalize honey bee cells. We were able to revive cells successfully after several months of cryogenic storage and we show how the proteome varies between freshly collected and cultured embryonic cells.  相似文献   
24.
复方蜂毒注射液对大鼠实验性肝纤维化的治疗作用   总被引:4,自引:0,他引:4  
为了研制防治肝纤维化的有效药物,用蜂毒及联合苦参碱的复方制剂,对大鼠实验性肝纤维化进行了治疗观察。结果显示,治疗组肝脏中羟脯氨酸、Ⅰ型胶原明显低于模型组并有显著性差异(P<0.01);血清中Ⅰ型胶原也明显低于模型组(P<0.01);肝脏重量低于模型组2g左右;肝组织病理切片观察到治疗组肝纤维化发生率明显低于模型组。实验结果表明,复方蜂毒对大鼠实验性肝纤维化有治疗作用。  相似文献   
25.
Red ginseng and fermented red ginseng were prepared, and their composition of ginsenosides and antiischemic effect were investigated. When ginseng was steamed at 98-100 degrees C for 4 h and dried for 5 h at 60 degrees C, and extracted with alcohol, its main components were ginsenoside Rg3> ginsenoside Rb1 > ginsenoside Rb2. When the ginseng was suspended in water and fermented for 5 days by previously cultured Bifidobacterium H-1 and freeze-dried (fermented red ginseng), its main components were compound K > ginsenoside Rg3 > or = ginsenoside Rh2. Orally administered red ginseng extract did not protect ischemia-reperfusion brain injury. However, fermented red ginseng significantly protected ischemica-reperfusion brain injury. These results suggest that ginsenoside Rh2 and compound K, which was found to be at a higher content in fermented red ginseng than red ginseng, may improve ischemic brain injury.  相似文献   
26.
红曲提取物对体外培养成骨细胞的作用研究   总被引:2,自引:0,他引:2  
目的:研究红曲不同提取物对体外培养大鼠成骨细胞(ROB)增殖、分化的影响。方法:采用新生大鼠颅骨分离培养ROB,MTT法测定细胞增殖,碱性磷酸酶(ALP)试剂盒法测定ALP活性,观察红曲提取物对ROB增殖、分化的作用,同时考察了MTT法和ALP试剂盒法中细胞数和吸收值之间的线性关系。结果:10^-2和10^-3mg/ml的水提物能刺激ROB的增殖(P〈0.05),10^-3mg/ml的水提物还能提高ROB的ALP活性(P〈0.05);10^-2和10^-3mg/ml的95%乙醇提取物对ROB的增殖与分化均有明显的促进作用(P〈0.05或P〈0.01)。结论:红曲水提物和95%乙醇提取物均能促进ROB骨形成过程中增殖、分化,95%乙醇提取物作用效果显著。  相似文献   
27.
Honey is a bee‐derived, supersaturated solution composed mainly of fructose and glucose, and containing proteins and amino acids, vitamins, enzymes, minerals, and other minor components. Historical records of honey skin uses date back to the earliest civilizations, showing that honey has been frequently used as a binder or vehicle, but also for its therapeutic virtues. Antimicrobial properties are pivotal in dermatological applications, owing to enzymatic H2O2 release or the presence of active components, like methylglyoxal in manuka, while medical‐grade honey is also available. Honey is particularly suitable as a dressing for wounds and burns and has also been included in treatments against pityriasis, tinea, seborrhea, dandruff, diaper dermatitis, psoriasis, hemorrhoids, and anal fissure. In cosmetic formulations, it exerts emollient, humectant, soothing, and hair conditioning effects, keeps the skin juvenile and retards wrinkle formation, regulates pH and prevents pathogen infections. Honey‐based cosmetic products include lip ointments, cleansing milks, hydrating creams, after sun, tonic lotions, shampoos, and conditioners. The used amounts range between 1 and 10%, but concentrations up to 70% can be reached by mixing with oils, gel, and emulsifiers, or polymer entrapment. Intermediate‐moisture, dried, and chemically modified honeys are also used. Mechanisms of action on skin cells are deeply conditioned by the botanical sources and include antioxidant activity, the induction of cytokines and matrix metalloproteinase expression, as well as epithelial‐mesenchymal transition in wounded epidermis. Future achievements, throwing light on honey chemistry and pharmacological traits, will open the way to new therapeutic approaches and add considerable market value to the product.  相似文献   
28.
In the present study, attempts have been made to determine the effects of honey on intestinal morphology, postoperative adhesions, and the healing of colonic anastomoses in the rats after colonic resection and anastomosis. Thirty-six rats were randomly divided into three groups each including 12 animals. Colonic resection and anastomosis were performed on all animals. Rats were fed with standard rat chow in group I, standard rat chow plus 10 g/kg/day honey in group II and artificial honey including the same caloric amount with honey in group III. Adhesion scores, bursting pressures and histopathological examinations were evaluated. Colonic bursting pressures of honey group were significantly better than control and artificial honey groups. Histological analysis of anastomotic site showed that submucosa and muscularis propria were nearly filled with granulation tissue and regular fibrin matrix in honey group. There was statistically significant difference between the adhesion scores of honey vs artificial honey and control groups. The scores of histological changes of ileum in honey group were significantly different from other groups. These results indicate a protective role of honey against intraabdominal adhesions and anastomotic dehiscence.  相似文献   
29.
Honey is reported to contain various compounds such as phenols, vitamins and antioxidants. The present study investigates the anticancer potential of Tualang honey (Agromas) (TH) in human breast (MCF-7 and MDA-MB-231) and cervical (HeLa) cancer cell lines; as well as in the normal breast epithelial cell line, MCF-10A. The cells were treated with increasing doses of TH (1-10%) for up to 72 h. Increase in lactate dehydrogenase (LDH) leakage from the cell membranes indicates that TH is cytotoxic to all three cancer cells with effective concentrations (EC50) of 2.4-2.8%. TH is however, not cytotoxic to the MCF-10A cells. Reactivity with annexin V fluorescence antibody and propidium iodide as analysed by flow cytometry and fluorescence microscopy shows that apoptosis occurred in these cancer cells. TH also reduced the mitochondrial membrane potential (Δψm) in the cancer cell lines after 24 h of treatment. The activation of caspase-3/7 and -9 was observed in all TH-treated cancer cells indicating the involvement of mitochondrial apoptotic pathway. This study shows that TH has significant anticancer activity against human breast and cervical cancer cell lines.  相似文献   
30.
目的建立补中益气丸(蜜丸)蜂蜜中葡萄糖、果糖、蔗糖、麦芽糖含量测定方法,以监控补中益气丸质量。方法 采用高效液相色谱-示差折光检测(HPLC-RD)法;色谱柱为Prevail Carbohydrate ES(250mm×4.6mm,5μm);流动相为乙腈-水(75∶25);流速1.0mL·min-1;柱温:35℃。结果葡萄糖、果糖、蔗糖、麦芽糖对照品分别在17.868~179.14、16.144~161.44、3.016~30.16、6.565~98.475μg线性关系良好,4种成分加样回收率分别为97.1%、101.9%、102.6%、95.9%,RSD分别为0.8%、2.0%、0.8%、1.3%(n=6)。结论该方法操作简便,灵敏度高,重复性好,可用于补中益气丸中蜂蜜的含量测定。  相似文献   
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