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目的:桥本甲状腺炎是一种自身免疫性甲状腺疾病,且其发病率呈逐年上升趋势,在医疗实践中,HT 被认为是原发性甲状腺
功能减退最常见的原因,同时较易发生甲状腺癌和淋巴瘤。另外,HT 缺乏早期诊断标准,临床上发病隐匿且表现多样,病人多不
易察觉而延误治疗。本文旨在应用microRNA 芯片技术系统筛查HT病变甲状腺组织,以此研究并揭示其HT 的miRNA 表达谱
变化。方法:本研究首先采用microRNA芯片技术,对正常甲状腺组织及桥本甲状腺炎甲状腺组织中microRNA 的表达进行比较,
筛选桥本甲状腺炎中差异性表达的miRNAs。结果:与正常甲状腺相比,在桥本甲状腺炎及其合并甲状腺乳头状癌的一侧桥本甲
状腺炎中分别有39 个和25 个miRNAs 分子发生了差异性表达(P<0.05),比较2 组中共有的miRNAs 发现,miR-142-3p、
miR-338-3p、miR-454、miR-146a、miR-29b-1*、miR-150、miR-223 表达上调,miR-654-5p、miR-601、miR-198、miR-1226* 表达下调
(log2 FC≥ 2,P<0.05);而miR-142-5p 在原发性桥本甲状腺炎中表达显著性升高近8 倍(log2 FC=7.959,P<0.01)。结论:我们通
过microRNA芯片,首次直接系统筛查了桥本甲状腺炎病变组织相关miRNA 表达谱,总体上初步掌握了与正常甲状腺相比,桥
本甲状腺炎及合并甲状腺乳头状癌时其miRNA 表达谱的变化情况,为我们后续的研究提供了方向与基础。 相似文献
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目的:比较血小板生成素与白介素-11治疗胃癌患者术后化疗血小板减少症的时效和安全性。方法:术后辅助化疗出现血小板计数低于75×109/L的进展期胃癌患者68例,将其分为TPO组与IL-11组,分别为35例和33例。分别皮下注射rhTPO 15000U,每日1次;rhIL-11 1.5 mg,每日1次,当血小板计数125×109/L或比用药前上升50×109/L,即停止给药,疗程最长为14天。每3天抽取外周静脉血2 m L,通过全自动血液分析仪测定血小板计数,密切观察出现的不良反应并记录。比较两组患者不同临床病理资料、血小板计数、血小板计数升至75×109/L和125×109/L的时程、药物不良反应。结果:两组患者年龄、性别、化疗方案、血小板最低值出现的化疗周期及临床病理分期的比较均没有统计学差异(P值均0.05)。TPO组与IL-11组血小板动态值的比较,第9天出现显著差异(P=0.032)。TPO组与IL-11组血小板计数恢复至75×109/L和125×109/L所需的时间,有显著差异(P=0.041,P=0.013)。TPO组中,有3例(8.6%)患者发生不良反应,IL-11组中,有13例(39.4%)患者发生不良反应,TPO组患者出现的不良反应少且较轻微(P=0.006)。结论:rhTPO治疗胃癌患者术后化疗血小板减少症时效快,安全性好。 相似文献
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Detection and genotyping of group A rotaviruses isolated from sewage samples in Monastir,Tunisia between April 2007 and April 2010 下载免费PDF全文
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Plasma membranes (1–2 mg protein) prepared from the livers of adult male rats and human organ donors were incubated with 0.6 μM [α-32P] guanosine triphosphate (GTP) in an adenosine triphosphate (ATP)-regenerating buffer at 37°C for 1 h; during this incubation, the [32P]GTP is hydrolyzed and the nucleotide that is predominantly bound to the membranes is [32P] guanosine diphosphate (GDP). [32P]GDP release from the liver membranes was proportional to the protein concentration and increased as a function of time. At 5 mM, Ca2+, Mg2+, Mn2+, and Zn2+ maximally inhibited GDP release by 80–90%, whereas, 5 mM Cu2+ maximally stimulated the reaction by 100%. Therefore, cations were not included in the buffer used in the GDP release step. One μM Gpp(NH)p (5′-guanylylimidodiphosphate), a nonhydrolyzable analog of GTP, maximally stimulated [32P]GDP release in the liver membranes by up to 30%. Although 10 nM Gpp(NH)p had no effect on GDP release, it appeared to stabilize the hormonal effect by blocking further GDP/GTP exchange. In the rat membranes, 1–100 nM glucagon (used as a positive control) stimulated [32P]GDP release by about 17% (P < .05); similarly, 0.1–100 nM insulin stimulated [32P]GDP release by 10–13% (P < .05). In the human membranes, 10 pM to 100 nM insulin stimulated [32P]GDP release by 7–10%. In the rat membranes, 10 nM insulin stimulated [32P]GDP release by 17 and 24% at 2 and 4 min, respectively (P < .05); in the human membranes, 10 nM insulin stimulated [32P]GDP release by about 9% at 2 and 4 min. Normal rabbit IgG (used as a control for insulin receptor antibody) by itself stimulated the GDP release by rat and human membranes. However, the stimulation of the GDP release by insulin receptor antibody was consistently higher than that observed with normal rabbit IgG. Four to 15 μg of insulin receptor antibody stimulated [32P]GDP release by 12–22% (P < .05) and 7–14% in rat and human membranes, respectively. These results indicate that ligand binding to the insulin receptor results in a functional interaction of the receptor with a guanine nucleotide-binding transducer protein (G protein) and activation of GTP/GDP exchange. 相似文献
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Neven Zarkovic Zoran Ilic Mislav Jurin R. Jrg Schaur Herbert Puhl Hermann Esterbauer 《Cell biochemistry and function》1993,11(4):279-286
The aim of this study was to analyze the growth response of HeLa cells over a prolonged period of time to a single exposure of physiological and supraphysiological concentrations of 4-hydroxynonenal (HNE), a peroxidation product of omega-6-polyunsaturated fatty acids. Furthermore, the growth modulating effect of serum factors, particularly albumin, on the growth pattern was examined. The effects of HNE on the growth rate and viability of the cells, as well as on the incorporation of labelled amino acids were monitored daily over a period of four days. Fetal calf serum not only had a growth stimualting effect but also modulated the action of HNE. In neither respect was albumin able to substitute for serum indicating that the influence of serum was not exerted via an albumin–HNE conjugate. HNE had a clear dose-dependent effect and a distinction could be made between a supraphysiological concentration (100 μM), which was primarily cytotoxic and a physiological range (below 10 μM) which showed growth modulatory effects. These effects consisted of a transient inhibition in the initial phase of the cell growth, which under optimal conditions (in presence of serum) was followed by a period of increased proliferation, compared to untreated control cultures, until confluence was attained. It is suggested that HNE is not only a toxic product of lipid peroxidation, but a physiological growth regulating factor as well. 相似文献
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《Bioorganic & medicinal chemistry》2019,27(15):3279-3284
Photodynamic therapy (PDT) is a treatment method using light and photosensitizers (PSs), which is categorized as a non-invasive surgery treatment for cancers. When the tumor is exposed to a specific light, the PSs become active and generate reactive oxygen species (ROS), mainly singlet oxygen which kills nearby cancer cells. PDT is becoming more widely recognized as a valuable treatment option for localized cancers and pre-cancers of skin as it has no long-term effects on the patient. But, due to the limited penetration rate of light into the skin and other organs, PDT can’t be used to treat large cancer cells or cancer cells that have grown deeply into the skin or other organs. Hence, in this study, our focus centers on synthesizing glucose-conjugated phthalocyanine (Pc) compatible with near-infrared (NIR) irradiation as second-generation photosensitizer, so that PDT can be used in a wider range to treat cancers without obstacles. 相似文献
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Rongsheng Chen Xiaobo Zhang Changsheng Wang 《Journal of cellular biochemistry》2020,121(10):4043-4051
Multiple myeloma (MM) is defined as the second most common hematological tumor in the globe. Long noncoding RNAs (lncRNAs) have been reported to play stimulative or suppressive role in the progression of different carcinomas. The investigation of lncRNAs in MM is still inadequate. LncRNA HOXB cluster antisense RNA 1 (HOXB-AS1) was once revealed to facilitate glioma progression by affecting cellular activities of glioma cells. However, whether HOXB-AS1 participates in the development of MM still remains an enigma. In this study, we unveiled that HOXB-AS1 was highly expressed in MM and loss-of-function assays certified that HOXB-AS1 obstruction suppressed MM cell proliferation, and stimulated cell apoptosis. In addition, HOXB-AS1 could modulate fucosyltransferase 4 (FUT4) and FUT4-mediated Wnt/β-catenin pathway. In subsequence, it was observed from mechanism assays that HOXB-AS1 enhanced the interaction between ELAVL1 and FUT4 so as to stabilize FUT4 messenger RNA. In the end, rescue experiments affirmed that HOXB-AS1 affected the cell growth through FUT4 in MM. In conclusion, the whole modulation mechanism of HOXB-AS1/ELAVL1/FUT4 axis in MM was validated in this study, which suggested that HOXB-AS1 might function as a powerful and promising therapeutic biomarker for the clinical treatment of patients with MM. 相似文献