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肺癌在中国恶性肿瘤的发病率位居第一,随着低剂量薄层CT在肺癌筛查中的广泛应用,临床发现更多表现为非完全实性结节的肺腺癌,目前众多研究使CT影像学特征和肺腺癌病理的关系得到更进一步的认知,虽然CT能对部分非完全实性结节做出定性和定位诊断,但仍有部分非完全实性结节诊断困难,PET-CT结合了病灶的代谢信息和精确的定位信息,从而提高对肺部结节诊断的敏感性、特异性、准确性,综合多个文献PET-CT在非完全实性结节中的诊断分期价值较CT无明显提升,却在评估预后和制定合适手术方案上可以起到一定的作用,本文就PET-CT在SSN中的应用价值进行阐述。 相似文献
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A V Maksimenko E L Terent'eva O Iu Konovalova V P Torchilin 《Ukrainski? biokhimicheski? zhurnal》1988,60(2):20-25
Chondroitin sulphate forms noncovalent electrostatic biocatalyst-glycosaminoglycan complexes in the solutions of enzymes. Chondroitin sulphate also interacts with enzymes developing complexes after carbodiimide activation of its carboxylic groups. Relatively low-molecular weight of biocatalysts (chymotrypsin, superoxide dismutase) forms stable noncovalent conjugates with the additional interaction as compared with electrostatic complexes. High-molecular weight of enzymes (acid phosphatase) develops covalent conjugates. Chondroitin sulphate is proposed for covalent binding of large proteins and multi-enzymatic complexes to obtain their stabilized derivatives for medical application. 相似文献
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烟青虫感染核型多角体病毒后围食膜的病变 总被引:4,自引:1,他引:3
昆虫的围食膜是衬在昆虫中肠内一种网状的结构,它可充作虫体抵御外来病原侵染的一道屏障。关于鳞翅目昆虫幼虫感染了昆虫病毒后围食膜的病变问题,国内外鲜有报道。尤锡镇和康慧娟(1985)曾以实验证明家蚕围食膜对核型多角体病毒有灭活作用,而且认为核型多角体病毒不能侵染和破坏围食膜。Derksen和Granados(1988)则证明染病幼虫的围食膜因不同杆状病毒(包括两种核型多角体病 相似文献
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It has been found that superoxide radicals formed at autooxidation of Fe(II) ions or of their complexes with EDTA in the presence of NAD.H cause reduction of met-Hb into deoxy or oxy-form. Under the effect of hydroxyl radicals generated in the ultrasonic field in the presence of NADH reduction of met-Hb into the ferro-form (carboxy-Hb) was observed in Co atmosphere and not in O2 atmosphere. It was induced by a high oxidation rate of oxy-Hb by hydroxyl radicals into met-Hb as compared to carboxy-Hb. Reduction of met-Hb was shown to be accompanied with the formation of NAD+. The role of NAD. radicals in the reduction of met-Hb which acts as an antioxidant in respect to organic free radicals was discussed. 相似文献
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It is established that the activity of malate dehydrogenase and glucose-6-phosphate dehydrogenase in rats aged 1,3 and 12 months lowers under fasting and on high-fatty diet and in old animals (24 months) on a high-fatty diet only the glucose-6-phosphate dehydrogenase activity decreases. When rats after fasting are put on high-carbohydrate diet the activity value of the mentioned enzymes has already returned to the initial level after 12 hours in rats aged 1 and 12 months and in rats aged 3 months it exceeds that activity in intact rats. The rise in the activity of the determined enzymes is completely blocked by the preliminary administration of actinomycin D. The isocitrate dehydrogenase activity remains unchanged under conditions of maintaining animals on different diets. 相似文献
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Konovalova L. N. Strelnikova S. R. Zlobin N. E. Kharchenko P. N. Komakhin R. A. 《Applied Biochemistry and Microbiology》2021,57(7):800-807
Applied Biochemistry and Microbiology - The production of mesophilic protoplasts of potato (Solanum tuberosum L.) for transient gene expression is a required technological stage in the testing of... 相似文献
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The results of studying the postfire successional change of light-coniferous and small-leaved forests of the prienisey part of the East Sayan Region are presented based on the landscape ecology approach. A general diagram of the direction and rate of succession changes has been made and analyzed considering the pyrogenous factor. 相似文献