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排序方式: 共有360条查询结果,搜索用时 15 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.
4.
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   
5.
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   
6.
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   
7.
目的探讨蜂胶对糖尿病伤口愈合的作用及其机制。方法采用荧光电泳法,检测不同葡萄糖浓度(5、25mmol/L)和不同蜂胶浓度(10、50、100、200μg/ml)处理的体外培养的人成纤维细胞及单核巨噬细胞系的基质金属蛋白酶MMP-9蛋白的表达。结果高浓度葡萄糖(25mmol/L)状态下,MMP-9表达增加,但与低浓度(5mmol/L)比较,差异无统计学意义。蜂胶可显著降低MMP-9的表达,并呈剂量依赖性(P〈.05)。结论高糖能增加单核巨噬细胞系及成纤维细胞MMP-9的表达,可能会影响糖尿病患者伤口的愈合。蜂胶可抑制这些细胞MMP-9的表达,有益于细胞基质的积聚,从而有益于糖尿病患者伤口的愈合。  相似文献   
8.
目的:观察中西医结合方法与西医常规疗法治疗急性周炎的临床疗效。方法:对50例急性冠周炎患者用中西医结合的方法进行治疗(中西医结合组),48例用西医常规方法治疗(西医对照组),观察中西医结合组、西医对照组的效果和中西医结合组治疗前后牙龈指数的变化。结果:中西医结合组显效率达72.00%,与西医对照组疗效比较有显著性差异(P<0.05);中西医结合组治疗后牙龈指数下降,与治疗前及西医对照组治疗后比较均有显著性差异(P均<0.01)。结论:蜂胶可减轻炎症、疼痛,促进组织愈合,有利于急性冠周炎的治疗和康复。  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.
蜂胶对糖脂代谢的调节作用及机制研究进展   总被引:1,自引:0,他引:1  
蜂胶具有广泛的生物学活性和药理学活性。论述了蜂胶对高脂血症及糖尿病的防治作用及调节糖、脂代谢的作用机制,以期为蜂胶在高脂血症及糖尿病防治领域的进一步研究和开发利用提供参考。  相似文献   
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