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51.
52.
目的:了解兰州市门诊病人人乳头瘤病毒(HPV)感染情况、年龄分布及与宫颈病变相关性,免疫组化法测不同宫颈病变组中P16表达,了解P16在筛查宫颈癌及其癌前病变中的作用。方法:收集兰州市2009年10月至2011年3月782例门诊女病人,核酸分子快速导流杂交基因芯片技术(HyBrimax)对宫颈脱落细胞行HPV分型检测,分析门诊病人中HPV感染状况及年龄分布。部分细胞学异常或高危HPV阳性者阴道镜下宫颈活检,病理检查宫颈病变程度及与HPV感染相关性,免疫组化法检测宫颈组织中P16蛋白表达情况。结果:兰州市门诊782例病人中,HPV阳性率28.64%(224/782),21种亚型检测出17种,排在前5位亚型分别为HPV16、HPV58、HPV68、HPV52、HPV33,各年龄组间HPV感染差异有统计学意义(P〈0.05),21-30岁之间感染占37.42%。117例病检组织中,HPV在正常/炎症、CINⅠ、CINⅡ-Ⅲ、ICC组中阳性率分别为35.55%、65.60%、88.46%、100%,各组间HPV感染差异有统计学意义(P〈0.01),同时P16表达依次增高,阳性率分别为22.22%、56.25%、84.61%、100%,组间差异有统计学意义(X2=36.124,P=0.001)。结论:兰州市门诊病人HPV感染阳性率为28.64%,各年龄组间感染差异有统计学意义,随宫颈病变加重,HPV检出率及P16蛋白表达均增高,二者联合检测有助于早期诊断及治疗。 相似文献
53.
摘要目的:探讨沉默交配型信息调节因子2同源蛋白1(silentmatingtypeinformationregulation2homologyl,SIRTl)在宫颈癌化疗耐药中的作用及其机制。方法:体外培养人宫颈癌Hela细胞系和宫颈癌Hela/MMC耐药细胞亚系,westernblotting检测MMC对Hela和Hela/MMC细胞内SIRTl蛋白表达的影响;MTT法检测MMC及Nicotinamide对Hela和Hela/MMC细胞增殖的影响;AnnexinV-PI试验检测Hela/MMC细胞凋亡的亡的情况;RT—PCR方法检测耐药相关蛋白P—gP的mRNA表达情况。结果:正常情况下,Hela/MMC细胞中SIRTl的表达显著高于Hela细胞(P〈0.05),MMC处理的Hela/MMC细胞中SIRTl的表达显著高于未经MMC处理(P〈0.05)。Nicotinamide对Hela和Hela/MMC细胞具有相似的生长抑制作用,Nicotinamide可使MMC诱导的Hela/MMC细胞凋亡增加,同时降低细胞内P-gP的mRNA表达(P〈0.05)。结论:SIRTl表达下调能显著减轻Hela/MMC细胞对MMC的耐药性,其作用可能与P—gp有关。 相似文献
54.
《Chronobiology international》2013,30(9):819-824
Infection with human papillomavirus is an established risk factor for cervical carcinoma. However, the role of other environmental factors is less well established. To further investigate whether other agents may be involved, the authors have analyzed seasonal variation in cervical cancer with respect to month of birth and separately month of diagnosis. All 85 cases diagnosed in 15–24-yr-olds during the period 1968–2005 were extracted from the specialist population-based Northern Region Young Persons' Malignant Disease Registry. The chi-square heterogeneity test was used to assess overall nonuniform variation in month of birth and separately month of diagnosis. Poisson regression analysis was used to fit sinusoidal (harmonic) models to the data using month of birth and month of diagnosis in separate models. Based on month of birth, there was statistically significant heterogeneity (p?=?.03) and a significant sinusoidal pattern, with an incidence peak involving births in the autumn months (p?=?.03). Based on month of diagnosis, there was marginally significant heterogeneity (p?=?.06). The evidence of seasonal variation around time of birth for cervical carcinoma is highly novel and suggests possible early etiological involvement of environmental factors. (Author correspondence: Richard. McNally@ncl. ac. uk) 相似文献
55.
56.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1468-1470
Cell-free extracts from ripening seeds of Arctium lappa L. catalyzed the enantioselective formation of (-)-pinoresinol, (-)-lariciresinol and (-)-secoisolariciresinol from achiral coniferyl alcohol in the presence of NADPH and H2O2. The enantioselectivity of the lignan formation was opposite to that of the (+)-secoisolariciresinol formation catalyzed by cell-free extracts from petioles of the same plant species. 相似文献
57.
Hajime Taniguchi Yasukiyo Umemura Michinori Nakamura 《Bioscience, biotechnology, and biochemistry》2013,77(2):231-239
The acid-soluble nucleotides were extracted from the tubers of Jerusalem artichoke with percbloric acid, and separated and purified by means of adsorption on and elution from active charcoal, repeated chromatography on columns of Dowex I (Cl-), followed by paper chromatography. The following nucleotides have been characterized and/or identified: 5′-AMP, 3′-AMP, ADP, ATP, 5′-GMP, 2′-GMP, 3′-GMP, 2′,3′-cyclic GMP, GDP, GTP, 5′-UMP, UDP, UTP, NADP, UDP-glucose, UDP-galactose, UDP-fructose, UDP-N-acetylhexosamine and GDP-mannose.** Neither cytosine ribonucleotides nor deoxyribonucleotides have been detected. The significance of these observations is discussed. 相似文献
58.
《Bioscience, biotechnology, and biochemistry》2013,77(11):2936-2945
In developing plants, free N-glycans occur ubiquitously at micromolar concentrations. Such oligosaccharides have been proposed to be signaling molecules in plant development. As a part of a study to elucidate the physiological roles of de-N-glycosylation machinery involved in fruit ripening, we analyzed changes in the amounts and structural features of free N-glycans in tomato fruits at four ripening stages. The amount of high-mannose type free N-glycans increased significantly in accordance with fruit ripening, and the relative amounts of high-molecular size N-glycans, such as Man8-9GlcNAc1, became predominant. These observations suggest that the de-N-glycosylation machinery, including endo-β-N-acetylglucosaminidase (ENGase) activity, is stimulated in the later stages of fruit ripening. But contrary to expectation, we found that total ENGase activities in the tomato fruits did not vary significantly with the ripening process, suggesting that ENGase activity must be maintained at a certain level, and that the expression of α-mannosidase involved in the clearance of free N-glycans decreases during tomato fruit ripening. 相似文献
59.
《Bioscience, biotechnology, and biochemistry》2013,77(10):2174-2180
Some characteristics of phosphoglucose isomerase (PGI, EC 5.3.1.9) from banana were measured during fruit ripening of three banana cultivars. In banana, PGI was present as two dimeric isoenzymes, named PGI1 and PGI2, which had similar native molecular masses but differed in relation to heat stability and isoelectric point. Total PGI activity showed a distinct two-step change during fruit ripening. Before the climacteric period, PGI activity gradually decreased with the starch content, then its activity began to increase with sucrose accumulation. The ratio of PGI1, and PGI2 was constant, indicating that both enzymes would be involved in starch degradation and sucrose synthesis. PGI activity and changes in carbohydrate composition suggests the existence of some control to fit the requirements of the intense carbon flow from starch to sucrose. 相似文献
60.
Hai-xia Qin Jun Yang Hong-kai Cui Shao-ping Li Wei Zhang Xiao-li Ding Yong-hua Xia 《Cytotechnology》2013,65(4):643-653
A recent report showed that reversine treatment could induce murine myoblasts dedifferentiation into multipotent progenitor cells and inhibit proliferation of some tumors, and other reports showed that apoptosis of lung adenocarcinoma cells could be induced by aspirin. The aim of the present study was to evaluate the synergistic antitumor effects of reversine and aspirin on cervical cancer. The inhibition rate of reversine and aspirin on cervical cancer cell lines’ (HeLa and U14) was determined by MTT method, cell cycle of HeLa and U14 cells was analyzed by FACS, mitochondrial membrane potential of HeLa and U14 was detected using a JC-1 kit. HeLa and U14 colony formation was analyzed by soft agar colony formation assay. The expression of caspase-3, Bcl-2/Bax, cyclin D1 and p21 was detected by qRT-PCR and Western Blotting. Moreover, tumor weight and tumor volume was assessed using a murine model of cervical cancer with U14 cells subcutaneously (s.c.) administered into the neck, separately or combined with drug administration via the intraperitoneal (i.p.) route. The inhibition rate of cells in the combination group (10 μmol/L reversine, 10 mmol/L aspirin) increased significantly in comparison to that when the drugs were used alone (P < 0.05); moreover, this combination could synergistically inhibit the proliferation of five cervical cancer cell lines (HeLa, U14, Siha, Caski and C33A). In the therapeutic mouse model, tumor weight and tumor volume of cervical cancer bearing mice was more reduced when compared with the control agents (P < 0.05) in tumor-bearing mice. The combination of reversine and aspirin exerts synergistic growth inhibition and apoptosis induction on cervical cancers cells. 相似文献