717 resultados para HSV TK
Resumo:
This work addresses the challenging problem of unconstrained 3D human pose estimation (HPE) from a novel perspective. Existing approaches struggle to operate in realistic applications, mainly due to their scene-dependent priors, such as background segmentation and multi-camera network, which restrict their use in unconstrained environments. We therfore present a framework which applies action detection and 2D pose estimation techniques to infer 3D poses in an unconstrained video. Action detection offers spatiotemporal priors to 3D human pose estimation by both recognising and localising actions in space-time. Instead of holistic features, e.g. silhouettes, we leverage the flexibility of deformable part model to detect 2D body parts as a feature to estimate 3D poses. A new unconstrained pose dataset has been collected to justify the feasibility of our method, which demonstrated promising results, significantly outperforming the relevant state-of-the-arts. © 2013 IEEE.
Resumo:
In this Letter, we use a reconfigurable hologram to dynamically control the position of incidence of the pump beam onto a liquid-crystal dye-based laser. The results show that there is an increase in the stability of the laser output with time and the average power when compared with the output of the same laser when it is optically excited using a static pump beam. This technique also provides additional functionality, such as wavelength tuning and spatial shaping of the pump beam, both of which are demonstrated here. © 2013 Optical Society of America.
Resumo:
The presence of thymidine kinase (TK) is a feature of many large DNA viruses. Here, a TK gene homologue was cloned and characterized from Rana grylio virus (RGV), a member of family Iridoviridae. RGV TK encodes a protein of 195 aa with a predicted molecular mass of 22.1 kDa. Homologues of the protein were present in all the currently sequenced iridoviruses, and phylogenetic analysis showed that it was much close to cellular TK type 2 (TK2), deoxycytidine kinase (dCK) and deoxyguanosine kinase (dGK). Subsequently, Western blotting revealed TK expression increased with time from 6 h post-infection in RGV-infected cells. Using drug inhibition analysis by protein synthesis inhibitor (cycloheximide) and DNA replication inhibitor (cytosine arabinofuranoside), RGV TK was classified as the early expression gene during in vitro infection. Subcellular localization by TK-GFP fusion protein expression and immunofluorescence staining showed RGV TK was an exclusively cytoplasmic protein in fish cells. Collectively, current data indicate that RGV TK was an early gene of iridovirus which encoded a cytoplasmic protein in fish cells.
Resumo:
图像分割是数字图像处理领域的重要研究内容。随着数字图像处理技术的发展和相关学科的进步,图像分割在图像编辑、计算机视觉、医疗影像、遥感图像等方面都取得了良好的应用,而且具有巨大的应用潜力。 图像分割是一个既很基础又很复杂的问题。经过多年的发展,研究者提出了很多优秀的算法,取得了令人鼓舞的成就。但由于图像分割本身的不确定性和复杂性,还没有一种算法能够解决好所有的分割问题。为了使图像分割的结果更加符合用户需求,交互式的分割方法逐渐成为了图像分割算法的主流。交互方式的简化也就成为了研究者努力的目标。 另一方面,图切分技术(Graph-Cut)是应用于图像分割算法的一种重要工具。Lazy Snapping方法利用人工交互操作来提取图像信息,然后使用图切分来分割图像,取得了较好的分割效果。而且该方法的交互界面简单易用,对模糊边界有较快的响应速度,引起了研究者的重视,是一种结合人工交互与图切分技术的重要分割方法。 鉴于Lazy Snapping方法在处理色彩丰富、对比强烈的图像时出现的交互操作过多、分割容易出错的问题,本文提出了一种基于亮度分析的图像分割方法。该方法在HSV空间下,以亮度为依据来提取前景和背景的特征,取代或简化了Lazy Snapping中的人工操作步骤,然后用图切分技术来进行分割。这种方法能够提取到较准确的图像特征,有效地减轻了用户操作量,明显地改善了分割结果。
Resumo:
We investigate the photoinduced anisotropy of a photochromic material of pyrrylfulgide/PMMA films. It is proven that when the film is illuminated with a linear polarization light, an optical axis that has the same polarization as the excitation light could be induced in the film. A matrix of light spots with different polarizations is recorded on the pyrrylfulgide/PMMA film. When reading out with non-polarization light, the matrix of light spots shows no information of patterns. However, when reading out with different linear polarization lights, different patterns could be observed. The experiment confirms that the pyrrylfulgide/PMMA film could be used to record two different polarization patterns in a matrix of spots. This property may be applied in camouflage technology.
Resumo:
A bisfurylfulgide, E, E-3,4-bis[1-(2,5-dimethyl-3-furyl)ethylidene]-3,4-dihydrofuran-2,5-dione, is synthesized by Stobbe condensation reaction. The molecular structure of target compound is confirmed by single crystal X-ray crystallography analysis. It shows that the distances between two possible reaction sites of molecule are 0.3394 and 0.3406 nm respectively, which is favorable to photocyclization. The photochromic properties of this compound in different solvents are investigated, and the result shows that the compound exhibits excellent photochromic behavior. The primary result of applied research on parallel image storage is also presented.
Resumo:
A synthesized photochromic compound-pyrrylfulgide-is prepared as a thin film doped in a polymethylmethacrylate (PMMA) matrix. Under irradiation by UV light, the film converts from the bleached state into a colored state that has a maximum absorption at 635 nm and is thermally stable at room temperature. When the colored state is irradiated by a linearly polarized 650 nm laser, the film returns to the bleached state; photoinduced anisotropy is produced during this process. Application of optical image processing methods using the photoinduced anisotropy of the pyrrylfulgide/PMMA film is described. Examples in non-Fourier optical image processing, such as contrast reversal and image subtraction and summation, as well as in Fourier optical image processing, such as low-pass filtering and edge enhancement, are presented. (c) 2006 Optical Society of America.
Resumo:
Photoinduced anisotropy of a photochromic pyrrylfulgide/PMMA film was investigated by using two linearly polarized beams. Excitation by linearly polarized light induces into the film an optical axis that has the same polarization as the excitation beam. This causes a change of the transmittance and of the polarization state of the detection beam. With a microscope a matrix of 4x4 light spots with different polarizations were recorded in the pyrrylfulgide/PMMA film. If readout with non-polarized light, the matrix of light spots show no information pattern. However, when readout with differently polarized lights, different patterns can be displayed. The experiment demonstrates that pyrrylfulgide/PMMA films can be used to hide two differently polarized patterns, which may be applied in camouflage technology. (C) 2005 Optical Society of America.
Resumo:
1、喜树碱类衍生物抗HIV构效关系与作用机制研究 喜树碱为传统的抗肿瘤药物。本研究对经过化学结构修饰的喜树碱类衍生物进行抗HIV活性及作用机制的研究,并初步探讨了其抗HIV构效关系。 我们对喜树碱类衍生物A系列化合物A1(喜树碱)、A2(10-羟基喜树碱)及A3(7-羟基喜树碱)进行了抗HIV活性检测。化合物A1和A3有较好的抗HIV-1和抗HIV-2活性,化合物A2没有显示抗HIV活性。表明化合物A1的C-10位上-OH基团修饰可能会降低抗HIV活性,化合物A1的C-7位上-CH2OH基团修饰和C-20位-CH3缺失可能会提高其抗HIV活性。对化合物A3和A1的抗HIV机制研究发现:二者对整合酶有一定的结合活性,对慢性感染H9/HIV-1ⅢB 和Jurkat/HIV-1ⅢB细胞中病毒复制没有抑制活性、不能阻断H9/HIV-1ⅢB与正常细胞间的融合,对重组的HIV-1蛋白酶和逆转录酶没有抑制活性。化合物A1和A3不具有选择性杀伤HIV-1ⅢB慢性感染的H9和Jurkat细胞系的作用。进一步进行化合物A3诱导 H9和H9/HIV-1ⅢB、Jurkat和Jurkat/HIV-1ⅢB的凋亡实验显示,化合物A3诱导感染HIV-1ⅢB和未感染病毒细胞的凋亡没有选择性。据此我们初步认为化合物A3和A1的抗HIV作用可能与抑制整合酶活性有关,该化合物可能还作用于其它靶点。 喜树碱类衍生物B系列中化合物B1为20(S)-O - [-O-( 1'-氧基-2',2',6',6'-四甲基哌啶-4'-丁二酸)]-20-喜树碱酯,化合物B2为20(S)-O - [-N-( 1'-氧基-2',2',6',6'-四甲基-1',2',5',6'-四氢吡啶酰胺)-4'-丙氨酸)]-20-喜树碱酯)。我们对化合物B1和B2进行了抗HIV活性检测。结果显示:化合物B2有较好的抗HIV-1和抗HIV-21、喜树碱类衍生物抗HIV构效关系与作用机制研究 喜树碱为传统的抗肿瘤药物。本研究对经过化学结构修饰的喜树碱类衍生物进行抗HIV活性及作用机制的研究,并初步探讨了其抗HIV构效关系。 我们对喜树碱类衍生物A系列化合物A1(喜树碱)、A2(10-羟基喜树碱)及A3(7-羟基喜树碱)进行了抗HIV活性检测。化合物A1和A3有较好的抗HIV-1和抗HIV-2活性,化合物A2没有显示抗HIV活性。表明化合物A1的C-10位上-OH基团修饰可能会降低抗HIV活性,化合物A1的C-7位上-CH2OH基团修饰和C-20位-CH3缺失可能会提高其抗HIV活性。对化合物A3和A1的抗HIV机制研究发现:二者对整合酶有一定的结合活性,对慢性感染H9/HIV-1ⅢB 和Jurkat/HIV-1ⅢB细胞中病毒复制没有抑制活性、不能阻断H9/HIV-1ⅢB与正常细胞间的融合,对重组的HIV-1蛋白酶和逆转录酶没有抑制活性。化合物A1和A3不具有选择性杀伤HIV-1ⅢB慢性感染的H9和Jurkat细胞系的作用。进一步进行化合物A3诱导 H9和H9/HIV-1ⅢB、Jurkat和Jurkat/HIV-1ⅢB的凋亡实验显示,化合物A3诱导感染HIV-1ⅢB和未感染病毒细胞的凋亡没有选择性。据此我们初步认为化合物A3和A1的抗HIV作用可能与抑制整合酶活性有关,该化合物可能还作用于其它靶点。 喜树碱类衍生物B系列中化合物B1为20(S)-O - [-O-( 1'-氧基-2',2',6',6'-四甲基哌啶-4'-丁二酸)]-20-喜树碱酯,化合物B2为20(S)-O - [-N-( 1'-氧基-2',2',6',6'-四甲基-1',2',5',6'-四氢吡啶酰胺)-4'-丙氨酸)]-20-喜树碱酯)。我们对化合物B1和B2进行了抗HIV活性检测。结果显示:化合物B2有较好的抗HIV-1和抗HIV-2活性,而化合物B1的抗HIV活性差。表明化合物B1的C-4’位-CH2被-NH取代,同时C-3’位-CH3修饰可能会提高其抗HIV活性。对化合物B2的抗HIV机制研究发现,化合物B2对慢性感染H9/HIV-1ⅢB细胞中病毒复制没有抑制活性、不能阻断H9/HIV-1ⅢB与正常细胞间的融合,对HIV-1蛋白酶、重组的HIV-1逆转录酶及整合酶没有抑制活性。化合物B2不具有选择性杀伤HIV-1ⅢB慢性感染的H9细胞系的作用。化合物B2抗HIV的作用机制还需进一步研究。 2、HIV/AIDS患者疱疹病毒感染状况及性病患者的HIV感染状况分析 疱疹病毒是AIDS患者合并感染的常见病原体。引起人类疾病的8种疱疹病毒与HIV感染及AIDS进展、机会性感染、恶性肿瘤密切相关。为了解HIV/AIDS患者人类8型疱疹病毒感染状况,我们检测了30例AIDS患者、40例HIV携带者及70例正常对照的液标本中8型疱疹病毒感染状况。采用ELISA法检测单纯疱疹病毒1型(HSV-1)、单纯疱疹病毒2型(HSV-2)、水痘-带状疱疹病毒(VZV)和巨细胞病毒(CMV);采用PCR法检测EB病毒(EBV)、疱疹病毒6型(HHV-6)、疱疹病毒7型(HHV-7)及疱疹病毒8型(HHV-8)。结果显示,HIV/AIDS患者中HSV-1、HSV-2、VZV、CMV、HHV-6、HHV-8 阳性率均高于健康体检者,其中AIDS患者VZV感染率与HIV携带者有显著性差异;在AIDS患者中多种疱疹病毒共感染普遍存在,必须重视HIV/AIDS患者合并疱疹病毒感染的防治。 性病可促进HIV的传播,了解性病患者的HIV感染状况及临床特征具有重要的意义。在自愿接受HIV咨询检测的基础上,对临床确诊的412例性病患者进行HIV-1/2抗体检测,并对其临床特征进行分析研究。结果显示412例性病患者的HIV检出率为2.9%。性病患者中检出HIV阳性率依次为:尖锐湿疣(6.2%)、生殖器疱疹(4.2%)、梅毒(3.4%)、淋病(1.5%)及非淋菌性尿道炎(1.0%)。83.3%合并感染HIV的性病患者存在多性伴,商业性行为普遍存在,安全套使用率极低现象。感染HIV的尖锐湿疣及生殖器疱疹患者以频繁复发为突出表现,1例合并感染HIV的梅毒患者半年即进展为神经梅毒。性病患者是HIV感染的重要高危人群,危险性行为是其感染HIV和其它性病的主要原因,应该加强性病患者的HIV检测。对临床上频繁复发的尖锐湿疣及生殖器疱疹患者、快速进展的梅毒患者应高度怀疑合并HIV感染的可能。
Resumo:
本文直接针对当前严重的世界性问题-病毒传染性疾病,开展了五种天然低聚糖及其硫酸酯衍生物的制备、抗病毒活性研究以及具抗疱疹病毒活性低聚糖硫酸酯作用机制的初步探讨。中药的结构修饰是中药现代化的重要内容,本研究的开展结合了药学、药理学和构效学,进一步丰富了硫酸酯化糖类抗病毒活性研究,有助于获得抗病毒活性新型药物以用于病毒引起的各类疾病,具有重要的理论和应用意义。1。分别从多花黄精以及与之在种属上有着由近及远关系的大玉竹、天冬、魔芋(酶解干粉)和香菇(子实体)中用类似程序提取了五种低聚糖样品,分别命名为Pcos、Pmos、Acos、Apkos、Leos。单糖组成分析、凝胶柱层析、红外光谱分析以及基体辅助激光解吸-飞行时间质谱分析的结果表明五种样品属于分子量比较接近、单糖组成各异、糖链骨架结构不同的低聚糖。这为后面不同糖链骨架结构的低聚糖硫酸酯的制备、探讨低聚糖硫酸酯衍生物糖链结构与抗病毒活性的关系建立了基础。从香菇子实体中用酶法制备低糖为首次报道。2。采用氯磺酸-吡啶法分别制备了五种天然低聚会糖的硫酸酯衍生物,分别命名为S-Pcos、S-Pmos、S-Acos、S-Apkos、S-Leos,经硫含量分析、Biol-Gel P4 凝胶柱层析、红外光谱分析证明该方法成功地向低聚糖中引入了硫酸基团,为开展天然低聚糖及其硫酸酯的抗病毒活性研究准备了必备的材料。3。利用细胞病变抑制法、中性红染色法、病毒空斑抑制法开展了五种低聚糖及其硫酸酯的体外抗HSV-2活性研究,结果都表明五种天然低聚糖本身没有抗HSV-2活性,除S-Acos之外的四种不同糖链骨架结构的低聚糖硫酸酯产生大小不同的活性, 说明硫酸酯低聚糖的抗病毒活性具有普遍的意义,这就大大扩大了药源,也为新的抗病毒活性药物筛选提供了新的思路和途径。S-Acos没有抗HSV-2活性,可能是因为低聚糖硫酸酯的抗病毒活性还存在硫酸基团以外的其它因素在起作用。五种低聚糖硫酸酯能抑制乙型肝炎抗原表达,说明低聚糖硫酸酯可能具有广谱抗病毒活性,有很大的应用前景。大玉竹、天冬、魔芋低聚糖及其硫酸酯的抗病毒活性研究未见报道。四种具抗HSV-2活性的低聚糖硫酸酯中,以S-Pmos的抗HSV-2活性最好,具有潜在抗病毒药物开发应用价值,值得进一步研究开发。4。初步探讨了低聚糖硫酸酯的抗病毒作用机制,由不同时间加药实验结果推测四种低聚糖硫酸硫酯具有类似的作用机制,可能作用于HSV-2与细胞的吸附阶段,不能抑制病毒在细胞内的复制过程;低聚糖硫酸酯的作用对象为病毒;对病毒毒力的影响实验和撤药实验说明四种低聚硫酸酯不能杀灭HSV-2,仅起抑制作用。作用机制的研究不仅进一步明确了四种低聚糖硫酸酯的抗HSV-2活性,还为今后开发和临床应用该类潜在性抗病毒药物提供了实验基础和依据。
Resumo:
本学位论文主要研究一株放线菌发酵产物的抗肿瘤活性。先对该株放线菌进行活化培养,然后进行大批量发酵,发酵液经过冷冻离心,对离心得到的沉淀和上清液用不同极性的有机溶剂进行萃取,得到六个浸膏样品。对六个样品进行初步抗肿瘤活性检测。 然后对活性浸膏进行分离纯化和活性跟踪。本论文主要进行了如下的工作: 1、对菌种进行活化培养,利用该菌株在280C,200r.min-1条件下进行发酵实验,发酵时间为72h,发酵总量为15L。发酵液经过离心得到上清液和沉淀两部分。 2、分别用石油醚、乙酸乙酯、正丁醇萃取沉淀和上清液,得到编号为1—6的六个浸膏样品,对六个浸膏样品进行初步的细胞毒性和抗HepG2肿瘤活性实验,得出结论为5号样品活性最高。在没有分离纯化的情况下GI50达到0.76µg/mL。 3、对5号样品进行TLC实验,找出能够较好分离5号样品中各组分的溶剂组合,最后得出在氯仿:甲醇=8:1时分离效果较好。然后利用氯仿:甲醇=8:1的溶剂组合作为洗脱剂对5号样品进行过硅胶柱分离纯化并进行活性跟踪分离。 4、对分离纯化后得到的样品进行活性跟踪和结构分析。分离后得到样品A,在其浓度为10µg/ml时,抗肿瘤实验细胞的生长率为73.5%。在浓度为1.0mg/ml时,抗单纯疱疹病毒率(HSVⅡ)为74.5%。结构分析得知其分子式最可能为C41H43N8O4. This dissertation studied about the anti-tumor activity of an actinomycete fermentation product. First, we cultured the actinomycete. Second, we fermented it in large quantities, and then centrifuged the fermentation fluid; the next step is that we extract sedimentation and supernatant in different polar organic solvents, in turn to obtained six samples, which were detected about anti-tumor activity. Last, we purified active sample and tracked activity of it. We carried out the following research work: 1. Activation, culture and screening of the actinomyces was carried on. We used the screening strain to carry on the fermentation when the conditions are 280C,200r.min-1,the fermentation time is 72h. Fermentation fluid volume is 15L.And we obtained sedimentation and supernatant after fermentation fluid was centrifuged. 2. We used Petroleum ether, ethyl acetate, n-butanol separately to extract sedimentation and supernatant, and obtained six samples that were numbered 1-6. From the preliminary cell toxicity and the anti-tumor(HepG2) bioactivity experiment, we found that No.5 sample has the highest activity in the samples; the GI50 was 0.76µg/ml which has not been purified. 3. We Carried on TLC experiment on the No.5 sample, found the solvent composition that can separate each component of the No.5 sample. At last, we found that when the proportions are tri-chloromethane: methyl alcohol = 8:1, the Separation result was the best, and then we used the Solvent composition which proportion are tri-chloromethane: methyl alcohol = 8:1 as eluant to Purify No.5 sample by silica gel column. 4. We tracked the activity of pure sample obtained from Purification and analyzed structure of these substances. We got a compound A after separation, and the cell growth rate was 73.5% when its concentration was 10µg/ml. The anti-virus(HSVⅡ) rate was 74.5% when its concentration was 1.0mg/ml. We analyzed the Structure of A, and informed its molecular formula that was the most likely for C41H43N8O4.
Resumo:
We present results on the system size dependence of high transverse momentum di-hadron correlations at root s(NN) = 200 GeV as measured by STAR at RHIC. Measurements in d + Au, Cu + Cu and Au + Au collisions reveal similar jet-like near-side correlation yields (correlations at small angular separation Delta phi similar to 0, Delta eta similar to 0) for all systems and centralities. Previous measurements have shown Chat the away-side (Delta phi similar to pi) yield is suppressed in heavy-ion collisions. We present measurements of the away-side Suppression as a function of transverse momentum and centrality in Cu + Cu and Au + Au collisions. The suppression is found to be similar in Cu + Cu and An + An collisions at a similar number of participants. The results are compared to theoretical calculations based on the patron quenching model and the modified fragmentation model. The observed differences between data and theory indicate that the correlated yields presented here will further constrain dynamic energy loss models and provide information about the dynamic density profile in heavy-ion collisions. (C) 2009 Elsevier B.V. All rights reserved.
Resumo:
The contribution of B meson decays to nonphotonic electrons, which are mainly produced by the semileptonic decays of heavy-flavor mesons, in p + p collisions at root s = 200 GeV has been measured using azimuthal correlations between nonphotonic electrons and hadrons. The extracted B decay contribution is approximately 50% at a transverse momentum of p(T) >= 5 GeV/c. These measurements constrain the nuclear modification factor for electrons from B and D meson decays. The result indicates that B meson production in heavy ion collisions is also suppressed at high p(T).
Resumo:
200 GeV corresponding to baryon chemical potentials (mu(B)) between 200 and 20 MeV. Our measurements of the products kappa sigma(2) and S sigma, which can be related to theoretical calculations sensitive to baryon number susceptibilities and long-range correlations, are constant as functions of collision centrality. We compare these products with results from lattice QCD and various models without a critical point and study the root s(NN) dependence of kappa sigma(2). From the measurements at the three beam energies, we find no evidence for a critical point in the QCD phase diagram for mu(B) below 200 MeV.