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排序方式: 共有1113条查询结果,搜索用时 15 毫秒
31.
Allister Yingwei Tham Chinnasamy Gandhimathi Jayaraman Praveena Jayarama Reddy Venugopal Seeram Ramakrishna Srinivasan Dinesh Kumar 《International journal of molecular sciences》2016,17(8)
Bone transplants are used to treat fractures and increase new tissue development in bone tissue engineering. Grafting of massive implantations showing slow curing rate and results in cell death for poor vascularization. The potentials of biocomposite scaffolds to mimic extracellular matrix (ECM) and including new biomaterials could produce a better substitute for new bone tissue formation. A purpose of this study is to analyze polycaprolactone/silk fibroin/hyaluronic acid/minocycline hydrochloride (PCL/SF/HA/MH) nanoparticles initiate human mesenchymal stem cells (MSCs) proliferation and differentiation into osteogenesis. Electrospraying technique was used to develop PCL, PCL/SF, PCL/SF/HA and PCL/SF/HA/MH hybrid biocomposite nanoparticles and characterization was analyzed by field emission scanning electron microscope (FESEM), contact angle and Fourier transform infrared spectroscopy (FT-IR). The obtained results proved that the particle diameter and water contact angle obtained around 0.54 ± 0.12 to 3.2 ± 0.18 µm and 43.93 ± 10.8° to 133.1 ± 12.4° respectively. The cell proliferation and cell-nanoparticle interactions analyzed using (3-(4,5-dimethyl thiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt) MTS assay (Promega, Madison, WI, USA), FESEM for cell morphology and 5-Chloromethylfluorescein diacetate (CMFDA) dye for imaging live cells. Osteogenic differentiation was proved by expression of osteocalcin, alkaline phosphatase activity (ALP) and mineralization was confirmed by using alizarin red (ARS). The quantity of cells was considerably increased in PCL/SF/HA/MH nanoparticles when compare to all other biocomposite nanoparticles and the cell interaction was observed more on PCL/SF/HA/MH nanoparticles. The electrosprayed PCL/SF/HA/MH biocomposite nanoparticle significantly initiated increased cell proliferation, osteogenic differentiation and mineralization, which provide huge potential for bone tissue engineering. 相似文献
32.
Cleaning capacity of octenidine as root canal irrigant: A scanning electron microscopy study
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Hernán Coaguila‐Llerena Virgínia Stefanini da Silva Mario Tanomaru‐Filho Juliane Maria Guerreiro Tanomaru Gisele Faria 《Microscopy research and technique》2018,81(6):523-527
The aim of this study was to assess the cleaning capacity of the octenidine hydrochloride (OCT) used as root canal irrigant by scanning electron microscopy (SEM) analysis. Sixty human unirradicular extracted teeth were randomly distributed in 6 groups (n = 10) according to irrigant solutions which were used during root canal preparation: G1, 0.1% OCT; G2, 2% chlorhexidine (CHX); G3, 2.5% sodium hypochlorite (NaOCl); G4, OCT + 17% ethylenediaminetetraacetic acid (EDTA); G5, 2.5% NaOCl + 17% EDTA and G6, distilled water. All specimens were instrumented with ProTaper system up to F4. Teeth were sectioned and prepared for SEM. The smear layer was evaluated using a 5‐score system and the data were analyzed by Kruskal–Wallis and Dunn (α = 0.05). In all root canal thirds there was no significant difference between OCT, CHX, NaOCl, and water groups (p > .05), and these groups showed higher smear layer values than NaOCl + EDTA and OCT + EDTA groups (p < .05). There was no significant difference between NaOCl + EDTA and OCT + EDTA groups (p > .05). It was concluded that OCT used as a single root canal irrigant presented poor cleaning capacity and could be used in association with a final irrigation with EDTA to obtain smear layer removal. 相似文献
33.
HPLC法测定L-丙氨酸甲酯盐酸盐中L-丙氨酸含量 总被引:1,自引:0,他引:1
建立了HPLC法分离测定L-丙氨酸甲酯盐酸盐中L-丙氨酸含量。色谱条件为:Shim-packVP-ODS柱(150mm×4.6mm,5μm);流动相为甲醇-NaH2PO4水溶液,NaH2PO4溶液浓度为0.05mol·L-1、pH值为6.50(H3PO4调节),甲醇与NaH2PO4溶液体积比为1∶9;流速0.80mL·min-1;柱温为30℃;检测波长为210nm;进样量5μL。该方法的建立为L-丙氨酸甲酯盐酸盐的测定提供了新方法。 相似文献
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为进一步提升聚对亚苯基苯并二噁唑(PBO)材料的性价比并促进其工业化,研究了以4,6-二硝基间苯二酚为原料,先选择还原制得4-氨基-6-硝基间苯二酚盐酸盐,进而与对甲氧羰基苯甲酰氯进行缩环合获得苯并噁唑化合物,再催化加氢合成AB型PBO新单体2-(对甲氧羰基苯基)-5-氨基-6-羟基苯并噁唑(MAB),最后自缩聚反应制备PBO的新路线和新方法.结果表明:该方法具有原料易得、反应条件缓和、中间体稳定等新技术优势.合成的PBO树脂总收率达64%、特性黏数η>10 dl8226;g-1,新单体MAB的纯度>98%,具有稳定性优异和缩聚基团完全等当比等性质,以及均缩聚时间<20 h和过程易操作等技术特点,均为4,6-二氨基间苯二酚(DAR)共缩聚路线所难以比拟的.其综合经济性优于三氯化苯经DAR共缩聚的工业化路线,有望发展成易于实施PBO产业化的一项新技术. 相似文献
39.
黄连素对油脂抗氧化作用的研究 总被引:4,自引:1,他引:4
以稀硫酸水溶液作溶剂,采用浸渍法从黄连中提取黄连素。利用SCHALL烘箱法,通过测定丙二醛吸光度值和过氧化值来评价黄连素、以及黄连素与其它抗氧化剂复配后对油脂的抗氧化效果。结果表明,黄连素对油脂有抗氧化作用,而且具有计量效应关系;柠檬酸、酒石酸、茶多酚对黄连素的抗氧化作用均有协同增效作用。 相似文献
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