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41.
HPCE法测定蛹虫草及其培养物中核苷类化合物的含量 总被引:5,自引:0,他引:5
目的 建立蛹虫草中核苷类化合物的高效毛细管电泳测定法 ,比较天然蛹虫草及其培养物中核苷类化合物的含量。方法 在HV - 30 1高效毛细管电泳仪上进行定量分析 ,采用石英毛细管柱 ,以pH9.0的 4 0mmol·L-1 硼砂溶液作为电极缓冲液 ;分离电压为 1 6KV ;检测波长为 2 5 4nm。结果 天然蛹虫草中核苷类化合物主要集中在子座部分。人工培养蛹虫草子座和菌丝中虫草素的含量分别是天然蛹虫草子座中的 5 .0 4倍和 1 0 .85倍 ;液体培养蛹虫草菌丝中腺嘌呤、腺苷、尿苷、鸟苷含量均高于固体培养蛹虫草子座。结论 天然蛹虫草及其培养物中核苷类化合物的种类和含量具有较大的差异。高效毛细管电泳法可以用于蛹虫草的定量分析 ,具有分离度高、简便、准确 ,样品消耗少等特点 相似文献
42.
Association of angiotensin II type 1 receptor gene polymorphism with essential hypertension 总被引:15,自引:0,他引:15
The renin-angiotensin system is involved in control of blood pressure and salt and fluid homeostasis. Genes for components of this system have been of major focus in research on the causation of the common, complex, polygenic trait, essential hypertension (HT). Association of an A→C variant at nucleotide 1166 of the angiotensin II type 1 receptor (AT1 R) gene with HT, but an absence of linkage of this locus with this disease, has been reported recently. Since confirmation in a different setting is imperative, we performed a cross-sectional case-control study of the A1166C variant in a well-characterized group of 108 Caucasian HT subjects with a strong family history (two affected parents) and early onset disease. Genotyping was by mismatch polymerase chain reaction/ Bfr I restriction fragment length polymorphism analysis. Frequency of the C1166 allele was 0.40 in HTs and 0.29 in normotensives. The difference in genotype (χ2 = 13, P = 0.0015) and allele (χ2 = 5.3, P = 0.02) frequencies between the two groups was significant (odds ratio for CC vs AA+AC = 7.3 [95% CI, 1.9–31.9). The present results implicate the AT1 R gene, or a locus in linkage disequilibrium with the variant tested, in the causation of essential HT. 相似文献
43.
循环系统里的成熟红细胞在其生命过程里经历着氧化性衰老,相应细胞组份出现血红蛋白变性、膜蛋白交联、带3蛋白聚集以及带3蛋白降解等多种修饰。这些修饰作为红细胞膜上的衰老信号参与构成衰老细胞抗原,由此启动与IgG自身抗体(主要为带3蛋白抗体)的结合以及补体的沉淀,最终是免疫吞噬系统对异常细胞的识别清除.现就衰老红细胞与带3蛋白的关系作一综述。 相似文献
44.
小包装全氟丙烷气体动力学实验研究 总被引:1,自引:0,他引:1
为检验塑料小包装全氟丙烷气体(C3F8)在不同包装和储存方法时浓度变化,将装有5~7mlC3F8的聚氯乙烯小袋,根据不同储藏温度和外包装方法随机分成四组:(1)22℃聚乙烯外包装,(2)36℃聚乙烯外包装,(3)22℃铝箔真空外包装,(4)-29℃聚乙烯外包装;每一组C3F8小袋气体存放一定时间后,应用气相色谱分析方法进行浓度测量。结果:第3组C3F8浓度最高和稳定,第2组浓度随放置时间降低最明显,第4组是临床应用气体的储藏和包装方法,其30天样本浓度和第3组相等,但放置一年时浓度降低。结果显示:塑料小包装C3F8予以铝箔真空外包装是一种可行的方法,利于C3F8运输和普及;聚乙烯外包装的C3F8,应放在-29℃保存,时间不超过一年。 相似文献
45.
Abstract. A patient with immune-mediated thrombocytopenia (ITP) and chronic hepatitis C virus (HCV) infection for 11 years was given immunosuppressive treatment because of an activation of his ITP. After 6 weeks of treatment with cyclophosphamide, cyclosporin A and cortisone the patient decided not to continue taking his medication. One month later he was readmitted to hospital due to fever, cough and jaundice. Clinical investigation revealed his condition to be caused by an activation of his HCV infection. It is concluded that, in parallel to the situation in hepatitis B, immunosuppressive treatment of patients with HCV infection may lead to increased viral replication, resulting in severe liver damage when immunocompetence is regained. 相似文献
46.
Christopher B. O'Brien Barbara S. Henzel Larry Wolfe Karen Gutekunst Dilip Moonka 《Digestive diseases and sciences》1997,42(5):1087-1093
Reports suggest that response tointerferon-alpha therapy is influenced by both hepatitisC viral genotype and titer. Our aim was to determine ifdirect, automated, cycle sequencing of the PCR productfrom an HCV RNA detection assay could be used toreliably determine HCV genotype. In addition, theapproach was used to determine the HCV genotypedistribution in our patient population and to learn ifthere was a correlation between HCV genotype and RNAtiter that could be used to predict response totreatment. In all 143 consecutive patients were testedfor both HCV RNA titer and genotype. Automated, cycle sequencing of PCR product was highly effectiveand failed to yield a genotype in only 3 (2%) patients.The distribution of HCV genotypes was: 1a (40%), 1b(39%), 2a (2%), 2b (6%), 3a (4%). There were significant differences in the median HCV RNA titersbetween genotypes 1, 2, and 3. 6 High HCV RNA titers>4.4 × 106 copies/ml were only seenin genotype 1. However, the HCV RNA level should not beused as a surrogate marker of genotype because of a significantoverlap of titers within the genotypes. 相似文献
47.
Mary Steidl Matsui Isabella Illarda Nianci Wang Vincent A. DeLeo 《Experimental dermatology》1993,2(6):247-256
Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors. 相似文献
48.
本文报告260例恶性肿瘤患者血清维生素A、E、C水平的测定结果。发现除慢性白血病外,蓁7种恶性肿瘤患者血清维生素A水平平均显著低于健康人(P<0.01);急性白血,肝癌、食管癌患者血清维生素E水平显著低于健康人(P<0.05);急性粒细胞白血病、急性单核细胞白血病、肝癌患者血维生素C水平显著低于健康人(P<0.01)。本研究工作为维生素A、E、C药物在肿瘤临床上的应用提供了参考。 相似文献
49.
N. J. Besansky 《Insect molecular biology》1993,1(4):171-178
Codon usage was compiled for fourteen chromosomal genes and four retrotransposons from the mosquito Anopheles gambiae. Variation exists among chromosomal genes in the degree of bias. The genes showing the highest bias are probably most highly expressed. In these genes, the base composition at the third codon position is much richer in G + C than is the overall coding sequence. Thus, codon usage is biased toward G- or C-ending codons. Codon usage in each retrotransposon is quite different, not only from chromosomal genes but also from the other retrotransposons. Codon usage comparisons among homologous genes from An. gambiae and two other Dipterans, the yellow fever mosquito Aedes aegypti and the fruitfly Drosophila melanogaster, show that while there are similarities, particularly between An. gambiae and D. melanogaster in the preference for G-and C-ending codons, each species has evolved a distinct pattern of codon usage. 相似文献
50.