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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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Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson’s diseae. Study of the biological processes involved in physiological functions and vulnerability and death of these neurons is imparative to understanding the underlying causes and unraveling the cure for this common neurodegenerative disorder. Primary cultures of mesDA neurons provide a tool for investigation of the molecular, biochemical and electrophysiological properties, in order to understand the development, long-term survival and degeneration of these neurons during the course of disease. Here we present a detailed method for the isolation, culturing and maintenance of midbrain dopaminergic neurons from E12.5 mouse (or E14.5 rat) embryos. Optimized cell culture conditions in this protocol result in presence of axonal and dendritic projections, synaptic connections and other neuronal morphological properties, which make the cultures suitable for study of the physiological, cell biological and molecular characteristics of this neuronal population.  相似文献   
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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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Abstract. Anopheles stephensi mosquitoes which had fed upon mice infected with Plasmodium yoelii nigeriensis malaria parasites produced significantly fewer eggs than mosquitoes fed on an uninfected mouse. Fecundity reduction was more pronounced when the bloodmeal contained malaria gametocytes and the mosquitoes developed oocysts. Egg production and haematin excretion were correlated for uninfected bloodfed mosquitoes; the presence of P.y. nigeriensis in the blood affected this relationship. Reduced fecundity was associated with a significant reduction of bloodmeal size (measured by haematin excretion) in mosquitoes which ingested gametocytaemic blood. The bloodmeal size in mosquitoes fed on parasitaemic blood without gametocytes was not significantly reduced. The use of haematin assays for determination of bloodmeal size in mosquitoes is discussed.  相似文献   
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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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