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91.
目的对甘油明胶/壳聚糖(CGG)和玉米醇溶蛋白/壳聚糖(ZC)两种壳聚糖修饰生物材料的细胞相容性和蛋白吸附作用进行初步评价。方法应用M TT比色法,评价两种材料对L 929小鼠细胞的细胞毒性,测定他们对大鼠原代表皮细胞的细胞粘附率和细胞增殖率;同时应用考马斯亮兰G-250染色法测定材料对牛血清蛋白的吸附作用。结果本实验结果显示,两种壳聚糖修饰材料对L 929细胞生长抑制反应级别为1级或0级,属于无明显毒性作用。大鼠皮肤成纤维细胞在CGG上的粘附率和增殖率分别达到88.8%和96.0%;在ZC上的粘附率和增殖率分别达到80.7%和94.7%。两种材料不同时间对蛋白的吸附量存在有差异。结论两种修饰材料具有良好的细胞相容性,其中CGG在细胞体外增殖作用和蛋白吸附作用方面要优于单纯壳聚糖和ZC。 相似文献
92.
壳聚糖-明胶-磷酸三钙组织工程支架用于兔颅骨缺损的修复 总被引:2,自引:0,他引:2
目的探索壳聚糖-明胶-磷酸三钙作为骨组织工程支架用于骨缺损修复的可行性。方法采用二次冻干技术制备孔径200-400μmCS-Gel/TCP三维立体支架材料;新西兰兔12只随机分为两组,将兔骨髓基质细胞(MSC)进行体外培养、扩增、诱导为骨髓基质成骨细胞(MSO),并制备直径为15mm的颅骨全层圆形骨缺损。实验组与颅骨缺损处植入等大的MSO-支架复合体,对照组植入单纯支架,分别4、8周取材,组织切片与X线观察骨形成情况。结果MSO-支架复合体植入骨缺损区后,具有良好的骨修复效果,明显优于对照组。结论壳聚糖-明胶-磷酸三钙海绵状复合体是一种具有潜在临床应用价值的骨组织工程的支架材料组织工程。 相似文献
93.
Mendel V Simanowski HJ Scholz HC Heymann H 《Archives of orthopaedic and trauma surgery》2005,125(6):363-368
Introduction In spite of new surgical techniques and recently developed antibiotics, there is no satisfactory solution for the treatment of chronic posttraumatic osteomyelitis. The introduction of local antibiotic treatment with gentamicin-PMMA beads according to Klemm has provided new stimuli for the treatment of chronic osteomyelitis. With the development of collagen as an absorbable carrier substance, the disadvantages of the rigid carrier system became evident. Due to the varying surgical techniques and different forms of adjuvant therapy, it is difficult to assess therapeutic methods and compare different studies. Therefore, it seemed appropriate to study the effect of local treatment with different antibiotic carriers in the setting of an animal study.Materials and methods The proven rat model for Staphylococcus aureus-induced osteomyelitis was used to compare the results of monotherapy with cefazolin, gentamicin-PMMA beads, or gentamicin-containing collagen sponge with the combination of local and systemic antibiotic treatment.Results Single-agent therapy with parenterally administered cefazolin reduced the CFU from 3.7×106 to 2.9×104 g-1 of tibial bone. The effect on osteomyelitis was more pronounced with the local application of antibiotics. The best results were achieved with the gentamicin-containing collagen sponge which reduced the bacterial colony count to 1.4×102 CFU/g compared with 9.8×102 CFU/g achieved with gentamicin-PMMA beads. The effect was most marked using a 4-week combination therapy with local application of the gentamicin-containing collagen sponge and systemic administration of cefazolin. In 9 of 11 animals, no bacteria could be detected in the bone.Conclusion Each of the treatment modalities resulted in a significant therapeutic effect. Due to its ability to quickly release large amounts of gentamicin, the flexible gentamicin-containing collagen sponge proved to be superior to the rigid PMMA system. Although the gentamicin-containing collagen sponge provided high antibiotic concentration at the site of implantation, an additive effect was attained when combined with systemic antibiotic treatment. 相似文献
94.
95.
Daesungki-Tang (DST), a drug preparation consisting of four herbs, that is, Rhei radix et rhizoma (RR; the roots of Rheum coreanum Nakai, Daehwang in Korean), Aurantiii frutus immaturus (AFI; immature fruits of Poncirus trifolita Rafin., Jisil in Korean), Magnoliae cortex (MC; the stem bark of Magnolia officinalis Rehd. Et Wils., Hubak in Korean), and Mirabilite (MS; Matrii sulfas, Mangcho in Korean), is a traditional Korean herbal medicine that is widely used in the treatment of cancer metastasis, gastrointestinal complaints, vascular disorders, and atherosclerosis-related disorders. In this study, water extracts of DST and each of the four ingredient herbs were prepared. The extracts were tested for cytotoxic activity on human hepatocellular carcinoma cells, Hep3B cells using the XTT assay method. The inhibitory effect of the extracts on the invasion of Hep3B cells was also tested using matrigel precoated transwell chambers. DST effectively inhibited the invasion of Hep3B cells, compared with the control groups in a dose-dependent manner. In addition, a gelatin zymography assay showed that DST decreased the gelatinolytic activity of matrix metalloproteinases-2 (MMP-2; IC50 = 87 microg/ml) and -9 (MMP-9; IC50 = 75 microg/ml) that are secreted from Hep3B cells, respectively. Among the four herbal ingredients of DST, only MC has been shown to significantly inhibit the invasion of Hep3B cells and MMP-2 and -9 activities. From these results, it can be concluded that DST has some potential for use as an antitumor agent. 相似文献
96.
Osteogenic evaluation of glutaraldehyde crosslinked gelatin composite with fetal rat calvarial culture model 总被引:1,自引:0,他引:1
The cytotoxicity of the synthetic bone substitute composed of tricalcium phosphate and glutaraldehyde crosslinked gelatin (GTG) were evaluated by osteoblast cell culture. In a previous study, the GTG composites were soaked in distilled water for 1, 2, 4, 7, 14, 28, and 42 days, and then the solutions (or extracts) were cocultured with osteoblasts to evaluate the cytotoxicity of GTG composites by alive cell counting. In this study, the extracts were cocultured with the osteoblasts; thereafter, the concentration of transforming growth factor-beta (TGF-beta1) and prostaglandin E2 (PGE2) in the medium was analyzed to strictly reflect the biological effects of GTG composites on the growth of osteoblasts. In order to investigate the osteoconductive potential of the GTG composites on new bone formation in a relative short term, a model of neonatal rat calvarial organ culture was designed prior to animal experiments. Three experimental materials of 4, 8, and 12% GTG composites were evaluated by fetal rat calvarial organ culture for their ability for bone regeneration. Deproteinized bovine and porcine cancellous bone matrixes were used as the controlled materials. All the organ culture units were maintained in cultured medium for 5 weeks. Following the culture period, the morphology of tissue was observed under an optical microscope, and the quantitative evaluation of the new generation bone was determined by using a semiautomatic histomorphometeric method. Except in the initial 4 days, the concentration of TGF-beta1 of 4% and 8% GTG composites was higher than that of the blank group for all the other experimental time periods. The PGE2 concentration for 4% and 8% GTG composites was lower than that of the blank group. It revealed that the 4% and 8% GTG composites would not lead to inflammation and would promote osteoblast growth. The morphology and activity of the osteoblasts were not transformed or changed by the 2 GTG composites. For the 12% GTG composite, the performance of the in vitro condition was inferior to the blank group and the other 2 GTG composites. Although the concentration of TGF-beta1 and PGE2 was gradually back to normal after 14 days, the morphology of the osteoblasts was abnormal with features such as contracted cytoplast structures. The osteoblast was damaged perhaps in the initial stage. We suggested that the 4% and 8% GTG composites should be soaked in distilled water at least for 4 days before medical applications. The 12% GTG composite and the composites with a concentration of glutaraldehyde solution higher than 12% were not recommended as a medical prostheses in any condition. The fetal rat calvaria culture also showed the same results with the analysis of TGF-beta1 and PGE2. From the study, we could predict the results of animal experiments in the future. 相似文献
97.
目的:对采自中国南海的海绵Axinyssa sp.进行化学成分研究,从中寻找具有生物活性的次生代谢产物。方法:用硅胶和凝胶LH-20柱层析对海绵Axinyssa sp.的乙醚提取物进行分离纯化,并结合现代波谱技术对得到的化合物进行结构鉴定。结果:分离得到了4个化合物,其结构分别鉴定为theonellin isothiocyanate(1),theonellin formamide(2),7-isothiocyanato-7,8-dihydro-α-bisabolene(3)和axinysterol(4)。结论:化合物1-3均为首次从海绵Axinyssa sp.中分离得到,同时也是首次从中国海域的海洋生物中分离得到。 相似文献
98.
目的研究髓质海绵肾(MSK)的影像学表现,并提高其诊断准确性。方法临床疑诊MSK的13例患者中,起先8例经X线平片检查,11例经超声检查,7例经CT平扫,其中,3例又经CT增强扫描,随后,11例经静脉肾盂造影(IVP)证实,2例经手术病理证实。对所有患者的影像表现进行了回顾性分析。结果IVP显示集合管呈线状、囊状扩张。X线平片显示肾乳头、髓质区簇状排列的圆形、椭圆形致密影。超声显示围绕肾髓质放射状分布的小回声区和强回声光点。CT平扫示环绕肾小盏分布的点状或簇状结石影,髓质区饱满、明显增大,呈低密度影,增强后,结石影周围的集合管内造影剂蓄积,造成结石影增大的假象。结论IVP是诊断本病例的金标准,但它属于有创性检查,X线平片可作为本病的首选检查方法,而CT能清楚显示肾内结石的形态、大小及分布状况,尤其是髓质增大且呈低密度是本病一新的重要征象之一。 相似文献
99.
100.
本研究运用胶体金标记的Con A.明胶膜方法,检测2.5×10~(-4)M浓度的Zncl_2(模拟小鼠精浆中锌的浓度)对小鼠附睾尾部精子受精能力的影响,并运用原子吸收分光光度计测定了小鼠精子在获能过程中精子锌的释放,及高锌(5μg/ml)溶液对锌释放的影响。实验结果表明:锌能阻止小鼠精子获能过程中糖蛋白的丢失,以及能可逆性地抑制顶体蛋白酶的活性,从而影响精子的受精能力,认为精浆锌作用可能与抑制精子锌的释放,提高糟子内含锌浓度有关。本实验显示了锌应用于抗生育作用的可能性。 相似文献