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排序方式: 共有357条查询结果,搜索用时 281 毫秒
1.
Propolis allergy   总被引:1,自引:1,他引:0  
87% of the propolis product "LB-1", originally reported to be 1,1-dimethyl-allyl caffeic acid ester, was shown by GC/MS analysis to consist of 3 isomeric pentenyl caffeates, 63% of which are 1,1-dimethylallyl caffeate. These pentenyl caffeates proved to be the major sensitizers of propolis and of poplar bud secretion in our previous study. In addition, 3 further minor allergens have now been investigated. Experimental sensitization indicates that phenylethyl caffeate is as strong a sensitizer as the major allergen "LB-1", while benzyl salicylate is a moderate sensitizer. Benzyl cinnamate plays only a subordinate role. At least 3 further esters of caffeic acid or cinnamic acid remain to be studied. Interestingly, relationships between propolis and balsam of Peru were found. 8 compounds are common to both materials. Thus "cross-reactions" or concomitant reactions in propolis-sensitive individuals to balsam of Peru are explainable.  相似文献   
2.
Propolis contains a variety of polyphenolic compounds. We investigated the effect of a water-soluble derivatives of propolis (WSDP) and polyphenolic compounds, components of propolis, on growth of Ehrlich ascites tumour (EAT) in mice. Tumour in peritoneal cavity was produced by 2×106 EAT cells. WSDP and polyphenolic compounds (caffeic acid-CA, caffeic acid phenethyl ester-CAPE and quercetin-QU) were given to mice perorally (po). It was found that the volume of ascitic fluid induced by EAT cells and total number of cells present in the peritoneal cavity was markedly reduced in EAT-bearing mice treated with test components and the survival time of treated mice was prolonged. Inhibition of EAT growth was due to their effect on the immune system of mice. When innate and acquired immune responses were evaluated, a dose-related increase of cytotoxic T-cell, NK and B cells activity was observed in test components-treated mice. Furthermore, exposure of animals to test components increased functional activity of macrophages to produce factors regulating the function of B-, T-, and NK- cells respectively. In conclusion, these findings imply that the antitumour activity of WSDP and polyphenolic compounds of propolis enhanced host resistance in the EAT tumour model, increasing the activities of macrophages, cytotoxic T cells, B cells and NK cells.  相似文献   
3.
杨明  隋殿军  孙红  于德伟  崔志勇 《中成药》2005,27(9):1057-1059
目的:研究蜂胶总黄酮对急性心肌缺血大鼠心肌梗塞和血液流变学的影响.方法:采用大鼠冠状动脉结扎引起急性心肌梗塞模型,术后48 h测定血清中CK,LDH,AST活性.结果:蜂胶总黄酮可明显减少梗塞面积和降低心肌三酶CK、LDH、AST活性,对血瘀模型大鼠体外血栓形成具有明显的改善作用,对大鼠血液流变学各项指标,除升高血沉外,对全血比黏度、血浆比黏度和红细胞压积均有明显的降低作用.结论:蜂胶总黄酮对急性心肌缺血大鼠可明显减少梗塞面积和改善异常的血液流变学各项指标.  相似文献   
4.
5.
The article presents characteristics of wood/polypropylene composites, where the wood was treated with propolis extract (EEP) and innovative propolis-silane formulations. Special interest in propolis for wood impregnation is due to its antimicrobial properties. One propolis-silane formulation (EEP-TEOS/VTMOS) consisted of EEP, tetraethyl orthosilicate (TEOS), and vinyltrimethoxysilane (VTMOS), while the other (EEP-TEOS/OTEOS) contained EEP, tetraethyl orthosilicate (TEOS), and octyltriethoxysilane (OTEOS). The treated wood fillers were characterized by Fourier transform infrared spectroscopy (FTIR), atomic absorption spectrometry (AAS), and X-ray diffraction (XRD), while the composites were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and optical microscopy. The wood treated with EEP and propolis-silane formulations showed resistance against moulds, including Aspergillus niger, Chaetomium globosum, and Trichoderma viride. The chemical analyses confirmed presence of silanes and constituents of propolis in wood structure. In addition, treatment of wood with the propolis-silane formulations produced significant changes in nucleating abilities of wood in the polypropylene matrix, which was confirmed by an increase in crystallization temperature and crystal conversion, as well as a decrease in half-time of crystallization parameters compared to the untreated polymer matrix. In all the composites, the formation of a transcrystalline layer was observed, with the greatest rate recorded for the composite with the filler treated with EEP-TEOS/OTEOS. Moreover, impregnation of wood with propolis-silane formulations resulted in a considerable improvement of strength properties in the produced composites. A dependence was found between changes in the polymorphic structures of the polypropylene matrix and strength properties of composite materials. It needs to be stressed that to date literature sources have not reported on treatment of wood fillers using bifunctional modifiers providing a simultaneous effect of compatibility in the polymer-filler system or any protective effect against fungi.  相似文献   
6.
This study investigates the potential of propolis-embedded zeolite nanocomposites for dental implant application. Propolis-embedded zeolite nanocomposites were fabricated by complexation of propolis and zeolites. Then, they were pelleted with Poly(L-lactide) (PLA)/poly(ε-caprolactone) (PCL) polymer for the fabrication of a dental implant. The chemical properties of propolis were not changed during the fabrication of propolis-embedded zeolite nanocomposites in attenuated total reflection-fourier transform infra-red (ATR FT-IR) spectroscopy measurements. Propolis was continuously released from propolis-embedded zeolite nanocomposites over one month. PLA/PCL pellets containing propolis-embedded zeolite nanocomposites showed longer sustained release behavior compared to propolis-embedded zeolite nanocomposites. Propolis-embedded zeolite nanocomposite powder showed similar antibacterial activity against C. albicans in an agar plate and formed an inhibition zone as well as chlorohexidine (CHX) powder. Eluted propolis solution from PLA/PCL pellets also maintained antibacterial activity as well as CHX solution. Furthermore, eluted propolis solution from PLA/PCL pellets showed significant antibacterial efficacy against C. albicans, S. mutans and S. sobrinus. Dental implants fabricated from PLA/PCl polymer and propolis-embedded zeolite nanocomposites also have antibacterial efficacy and negligible cytotoxicity against normal cells. We suggest that PLA/PCl pellets containing propolis-embedded zeolite nanocomposites are promising candidates for dental implants.  相似文献   
7.
目的建立保健食品蜂胶中总砷的分析方法。方法采用微波消解法对蜂胶样品进行前处理,氢化物发生-原子荧光法进行测定。结果测定总砷的线性范围为0~90μg/L,相关系数为0.999 5,方法回收率为96.6%~101.7%,RSD为1.08%。结论实验表明,本法准确灵敏,简便高效,适用于蜂胶中总砷的测定。  相似文献   
8.
蜂胶的生物学活性与临床应用   总被引:16,自引:0,他引:16  
蜂胶(propolis)又名蜂巢蜡胶,是蜜蜂从各种植物(杨树、桦树、柳树、栎树、马栗及针叶树等)的嫩芽中采集的树脂,混有蜂蜜上腭腺分泌的和蜂蜡形成的一种固体胶状物.蜜蜂用它来填补蜂巢裂缝,粘连巢框,涂擦巢房壁,并掺和在蜂蜡中作封盖子脾及封盖成熟蜜脾用.  相似文献   
9.
目的了解蜂胶对牙龈卟啉单胞菌(porphyromonas gingival,Pg)生长的抑制作用及对人牙龈成纤维细胞的毒性作用。方法采用液体稀释法测定蜂胶对Pg的最小杀菌浓度(MBC),用MTT法测定不同浓度蜂胶作用24h后牙龈成纤维细胞的细胞相对增殖率(RGR),了解蜂胶作用24h后细胞连续7d的增殖回复情况。结果蜂胶对取的MBC为1.56g/L,相当于0.125~0.25mg/L的奥硝唑。蜂胶浓度为MBC时RGR达到70%以上;4g/L蜂胶组的RGR为52.1%,作用细胞24h后,连续7d细胞数持续增加,吸光度逐渐接近阴性对照组。结论蜂胶对Pg的生长有显著抑制作用,且细胞毒性较小,毒性作用可逆。  相似文献   
10.
目的 评价由改良的聚酰胺柱层析技术研制的辽西蜂胶醇提取物(EEP)对心肌细胞过氧化损伤的保护作用及强度.方法 参照文献方法并加以改进获得FEP样品,以1000μmol/L的Fe2 和500μmol/L的半胱氨酸造成心肌细胞过氧化损伤,通过检测培养液中乳酸脱氢酶(LDH)的漏出量、培养细胞丙二醛(MDA)和超氧化物歧化酶(SOD)含量等指标,对比研究EEP和槲皮素对心肌细胞过氧化损伤的保护作用.结果 EEP和槲皮素在25~100μg/Ml均能剂量依赖性地对抗培养介质中LDH漏出和培养细胞MDA的产生,并能对培养细胞SOD具有保护作用;抑制LDH漏出,EEP和槲皮素的IC50分别为22.9和27.4μg/Ml;抑制MDA产成,EEP和槲皮素的IC50分别为43.9和36.2μg/Ml;保护SOD活力,EEP和槲皮素对抗SOD活力降低的IC50分别为23.3和147.6μg/Ml.结论 对于Fe2 /半胱氨酸体系造成的培养乳鼠心肌细胞过氧化损伤模型,EEP对心肌细胞过氧化损伤和对SOD活性的保护作用均强于槲皮素,但对心肌细胞脂质过氧化的抑制作用,EEP略弱于槲皮素.  相似文献   
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