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目的对个青皮多糖及总黄酮含量进行测定。方法多糖采用水提醇沉法提取,硫酸-苯酚法显色,分光光度法进行含量测定;总黄酮采用回流提取法进行提取,分光光度法测定含量。结果个青皮多糖含量为4.99%,总黄酮含量为14.57%。结论本法简便、重现性好,可用于个青皮的质量控制。 相似文献
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目的 构建HIV-1 CN54株gagprotease基因嵌合脊髓灰质炎病毒cDNA的表达质粒,并鉴定、检测基因及其表达。方法 用PCR技术获得人免疫缺陷病毒CN54株的gagprotease基因,并使其两端带上合适的酶切住点,将其定向插入到包含脊髓灰质炎病毒cDNA的表达质粒pSVA14中,替代其部分结构基因,构建HIV基因嵌合缺陷性脊髓灰质炎病毒基因组的表达质粒。经筛选、鉴定后用脂质体转染技术将新构建的质粒转入Hela细胞内,用Western Blot方法检测目的基因在Hela细胞内的表达。结果 PCR技术扩增所得的人免疫缺陷病毒CN54株gagprotease基因经琼脂糖凝胶电泳、DNA测序证实成功获得,未引入突变碱基,筛选、鉴定证明gagprotease基因被正确定向插入到脊髓灰质炎病毒的cDNA序列之中,Western Blot检测到gagpro-tcase基因正确表达了相关蛋白。结论 成功构建了表达人免疫缺陷病毒CN54株gagprotease基因的缺陷性脊髓灰质炎病毒基因组嵌合质粒,为利用脊髓灰质炎病毒作人免疫缺陷病毒基因的表达载体奠定了基础,此研究对开发以脊髓灰质炎病毒为艾滋病的疫苗载体有重要意义。 相似文献
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Histopathology in rabbit Achilles tendon after operative tenolysis (longitudinal fiber incisions) 总被引:1,自引:0,他引:1
Friedrich T Schmidt W Jungmichel D Horn LC Josten C 《Scandinavian journal of medicine & science in sports》2001,11(1):4-8
The surgical treatment (tenolysis) of chronic Achilles tendinopathy is often successful. However, little is known about the postoperative intratendinous changes after this procedure. The study group consisted of 21 rabbits. Operative tenolysis was done in each case on one Achilles tendon (AT). The ATs of both legs were studied histologically and immunohistochemically using antibodies against collagen types I and III 2, 4 and 6 weeks postoperatively. Nine rabbits without operation served as controls. A significant uniform hypervascularization was noted in the entire operated tendon postoperatively, and this concurred with the contralateral nonoperated AT, but neither side showed changes in collagen fiber structure as judged by immunohistochemistry. We conclude that the tenolysis procedure triggers neoangiogenesis at the AT followed by increased blood flow and improved nutrition in the same. These changes could, at least partly, explain the often seen clinical success in surgically treated tendinopathy. 相似文献
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The aim of osteochondral transplantion is to transfer intact cartilage from joint areas that are not subject to much stress to zones in the main weightbearing region where there are defects. Even though the transplanted cartilage is not integrated into the tissue already present, hyaline structures have been detected histologically in biopsies and in animal experiments. The medium-term and the few long-term results are very promising. It depends on the genesis, the localization and the severity of the cartilage defect whether this treatment is indicated. Traumatic, locally circumscribed, osteochondral lesions of the femoral condyle grade III–IV (Outerbridge) are the ideal indication for transplantation; it is also possible in other joints, albeit with varying clinical results. Generalized osteoarthrosis is a contraindication to this procedure. So far it is not known how the progression of arthrosis is attenuated by osteochondral transplantation. 相似文献
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Hale JD; Valk PE; Watts JC; Kaufman L; Crooks LE; Higgins CB; Deconinck F 《Radiology》1985,157(3):727-733
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image. 相似文献