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《科学通报(英文版)》2012,(25):3398
The transfusion of red blood cells (RBC) is a critical component in the treatment of a number of acute and chronic medical problems. Indeed, approximately 75 million units of whole blood 相似文献
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利用多颜色空间特征融合方法检测近似目标 总被引:7,自引:0,他引:7
以棉花中羊毛、白头发、塑料膜等杂质的检测为应用背景,提出一种利用多颜色空间特征融合方法。该方法构建了颜色特征评价函数,对近似目标在不同颜色空间的特征表现进行评估,从中抽取近似目标的若干最优特征;再利用区域信息相关度权值小波分析算法进行多特征融合,获取近似目标的图像。实验结果表明,融合图像比原始图像及单色空间图像具有较高的图像信息量值,近似目标视觉特征明显增强。此方法为提取与背景特征相近的近似目标提供一条新思路。 相似文献
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Several observations suggest that retroviral infection is involved in the pathogenesis of the human demyelinating disease multiple sclerosis (MS). First, lymphadenopathy-associated virus/human T-lymphotropic virus type III (LAV/HTLV-III), the agent of acquired immune deficiency syndrome (AIDS), has been shown to be neurotropic in man. Second, the genetic organization of the lentivirus visna, which causes a chronic demyelinating disease of sheep, closely resembles that of LAV/HTLV-III. Recently, Koprowski and colleagues reported that MS is associated both with raised levels of circulating antibodies to HTLV-I and with the presence of HTLV-I-specific RNA within cell lines derived from the cerebrospinal fluid (CSF). Here we report that no HTLV-I-like or LAV/HTLV-III-like sequences can be detected, by in situ hybridization, in central nervous system (CNS) tissues from MS patients, and that nonspecific HTLV-I-like signal in peripheral blood mononuclear cells or in CSF cell lines is characteristic of MS. Furthermore, enzyme-linked immunosorbent assay (ELISA) analysis of circulating and CSF antibodies for HTLV-I reactivity fails to distinguish between MS and control groups. 相似文献
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【目的】研究克恩氏冬青叶片应答低温胁迫的蛋白表达情况,探讨克恩氏冬青耐寒的作用机理。【方法】以2年生幼苗为试材,对其进行-8 ℃和-16 ℃低温胁迫处理,运用双向电泳技术(2-DE)结合质谱技术(MALDI-TOF/TOF MS)检测并分析叶片差异表达蛋白,并对差异蛋白进行了生物信息学分析。【结果】在低温胁迫下,克恩氏冬青幼苗叶片中蛋白表达发生了明显变化,胁迫前后发现共有31个显著差异的蛋白质点,经质谱检测及数据库检索,成功鉴定了其中23个差异表达蛋白点。对其中的20个蛋白成功进行了功能分类,主要涉及蛋白质和氨基酸代谢、光合作用、氧化还原平衡、防御作用、碳水化合物代谢、脂类代谢、氮素代谢等生物学过程。【结论】克恩氏冬青应答低温胁迫是多种蛋白质共同作用的结果,主要通过调节多种代谢过程中的相关蛋白表达来发挥作用。 相似文献
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静电放电电流波形校准装置的研制与分析 总被引:1,自引:0,他引:1
根据IEC61000-4-2的要求,研制了2种不同结构形式的静电放电电流波形校准装置,对SchaffnerNSG438和KeyTek MZ-15/EC型静电放电枪的电流波形进行了校准测试.经在不同电压等级和电压极性下的多次测试发现:其中一种校准装置测得的静电放电电流波形与出厂结果相吻合,即该校准装置的设计是成功的.通过试验对比和定量分析发现,校准装置的分布参数对静电放电电流波形的上升沿有显著影响.对于静电放电电流波形校准装置,仅满足标准规定的电压驻波比指标是不够的,必须对分布参数的影响予以高度重视. 相似文献
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Proteomic analysis of long-term salinity stress-responsive proteins in Thellungiella halophila leaves 总被引:2,自引:0,他引:2
《科学通报(英文版)》2008,(22)
Salinity is one of the most severe environmental factors that may impair crop productivity. A proteomic study based on two-dimensional gel electrophoresis is performed in order to analyze the long-term salinity stress response of Thellungiella halophila, an Arabidopsis-related halophyte. Four-week-old seedlings are exposed to long-term salinity treatment. The total crude proteins are extracted from leaf blades, separated by 2-DE, stained with Coomassie Brilliant Blue, and differentially displayed spots are identified by MALDI-TOF MS or QTOF MS/MS. Among 900 protein spots reproducibly detected on each gel, 30 spots exhibit significant change and some of them are identified. The identified proteins include not only some previously characterized stress-responsive proteins such as TIR-NBS-LRR class disease resistance protein, ferritin-1, and pathogenesis-related protein 5, but also some proteins related to energy pathway, metabolism, RNA processing and protein degradation, as well as proteins with unknown functions. The possible functions of these proteins in salinity tolerance of T. halophila are discussed and it is suggested that the long-term salinity tolerance of T. halophila is achieved, at least partly, by enhancing defense system, adjusting energy and metabolic pathway and maintaining RNA structure. 相似文献
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The recent report by Koprowski et al. that human T-cell lymphotropic retroviruses (HTLVs) may be involved in the development of multiple sclerosis (MS) has aroused much interest. The report was based largely on immunological evidence, using enzyme-linked immunosorbent assays (ELISAs) with viral antigens or disrupted virions. We have accordingly sought confirmation by screening sera and cerebrospinal fluid (CSF) samples from MS patients against cell lines infected respectively with adult T-cell leukaemia (ATL) virus (ATLV/HTLV-I) of Japanese cells (MT-1 and MT-2 lines), our own isolate from British black patients with ATL, the MoT cell line which produce HTLV-II, and our own T-cell line containing a local isolate of acquired immune deficiency syndrome (AIDS) virus (C-LAV/HTLV-III). We have failed to find antibodies against these retroviruses in the sera or CSF. Furthermore, neither virus could be isolated from the peripheral white blood cells of two MS patients. 相似文献
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目的探讨多发性骨髓瘤(MM)的临床特征方法回顾性分析16例MM患者临床资料。结果16例病人均被误诊,误诊时间1到32个月,平均误诊时间13个月。最易被误诊为骨科疾病。结论对中年以上的反复感染发热、骨痛、贫血等都应考虑MM的可能,需进一步进行检查。 相似文献
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聚能杆式弹丸侵彻混凝土靶计算分析 总被引:1,自引:0,他引:1
根据已有的研究成果和理论,对聚能杆式弹丸侵彻混凝土靶问题进行了计算分析.首先,根据材料状态随撞击速度的变化规律,建立了聚能杆式弹丸侵靶过程中的侵彻模式的判别准则.其次,基于静态球形空腔膨胀理论求解出混凝土靶体的强度参数,并将其应用于侵彻模式的判别.最后,采用量纲分析方法对高速弹丸侵彻厚靶的经验模型进行分析,并在前人研究成果的基础上建立了聚能杆式弹丸侵彻混凝土靶的经验公式. 相似文献
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Injection of adult neurospheres induces recovery in a chronic model of multiple sclerosis 总被引:55,自引:0,他引:55
Pluchino S Quattrini A Brambilla E Gritti A Salani G Dina G Galli R Del Carro U Amadio S Bergami A Furlan R Comi G Vescovi AL Martino G 《Nature》2003,422(6933):688-694
Widespread demyelination and axonal loss are the pathological hallmarks of multiple sclerosis. The multifocal nature of this chronic inflammatory disease of the central nervous system complicates cellular therapy and puts emphasis on both the donor cell origin and the route of cell transplantation. We established syngenic adult neural stem cell cultures and injected them into an animal model of multiple sclerosis--experimental autoimmune encephalomyelitis (EAE) in the mouse--either intravenously or intracerebroventricularly. In both cases, significant numbers of donor cells entered into demyelinating areas of the central nervous system and differentiated into mature brain cells. Within these areas, oligodendrocyte progenitors markedly increased, with many of them being of donor origin and actively remyelinating axons. Furthermore, a significant reduction of astrogliosis and a marked decrease in the extent of demyelination and axonal loss were observed in transplanted animals. The functional impairment caused by EAE was almost abolished in transplanted mice, both clinically and neurophysiologically. Thus, adult neural precursor cells promote multifocal remyelination and functional recovery after intravenous or intrathecal injection in a chronic model of multiple sclerosis. 相似文献
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Voineagu I Wang X Johnston P Lowe JK Tian Y Horvath S Mill J Cantor RM Blencowe BJ Geschwind DH 《Nature》2011,474(7351):380-384
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AP Gregory CA Dendrou KE Attfield A Haghikia DK Xifara F Butter G Poschmann G Kaur L Lambert OA Leach S Prömel D Punwani JH Felce SJ Davis R Gold FC Nielsen RM Siegel M Mann JI Bell G McVean L Fugger 《Nature》2012,488(7412):508-511
Although there has been much success in identifying genetic variants associated with common diseases using genome-wide association studies (GWAS), it has been difficult to demonstrate which variants are causal and what role they have in disease. Moreover, the modest contribution that these variants make to disease risk has raised questions regarding their medical relevance. Here we have investigated a single nucleotide polymorphism (SNP) in the TNFRSF1A gene, that encodes tumour necrosis factor receptor 1 (TNFR1), which was discovered through GWAS to be associated with multiple sclerosis (MS), but not with other autoimmune conditions such as rheumatoid arthritis, psoriasis and Crohn’s disease. By analysing MS GWAS data in conjunction with the 1000 Genomes Project data we provide genetic evidence that strongly implicates this SNP, rs1800693, as the causal variant in the TNFRSF1A region. We further substantiate this through functional studies showing that the MS risk allele directs expression of a novel, soluble form of TNFR1 that can block TNF. Importantly, TNF-blocking drugs can promote onset or exacerbation of MS, but they have proven highly efficacious in the treatment of autoimmune diseases for which there is no association with rs1800693. This indicates that the clinical experience with these drugs parallels the disease association of rs1800693, and that the MS-associated TNFR1 variant mimics the effect of TNF-blocking drugs. Hence, our study demonstrates that clinical practice can be informed by comparing GWAS across common autoimmune diseases and by investigating the functional consequences of the disease-associated genetic variation. 相似文献
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T-cell recognition of an immunodominant myelin basic protein epitope in multiple sclerosis. 总被引:52,自引:0,他引:52
Multiple sclerosis is thought to be an autoimmune disease of the central nervous system mediated by T cells specific for a myelin antigen. Myelin basic protein has been studied as a potential autoantigen in the disease because of its role as an encephalitogen in experimental autoimmune encephalomyelitis and post-viral encephalomyelitis and because of the presence in the blood of multiple sclerosis patients of in vivo-activated T cells reactive to myelin basic protein. Immune involvement in multiple sclerosis has been further suggested by the association with the major histocompatibility complex class II phenotype DR2, DQw1. To define the T-cell specificity toward myelin basic protein, 15,824 short-term T-cell lines were established from multiple sclerosis subjects, subjects with other neurological diseases, and normal controls. Here we report a higher frequency of T-cell lines reactive with a DR2-associated region of myelin basic protein between residues 84-102 in patients with multiple sclerosis compared with controls. A second region, identified between residues 143-168, was recognized equally in multiple sclerosis patients and controls and was associated with the DRw11 phenotype. These DR2 and DRw11 associations were also observed among T-cell lines generated from family members of a multiple sclerosis patient. The immunodominant 84-102 peptide from myelin basic protein was both DR2- and DQw1-restricted among different T-cell lines. These results raise the possibility that this immunodominant region may be encephalitogenic in some DR2+ individuals. 相似文献
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以SCTE预估系统为基础,用面元法建立了雷达静止和运动时目标近场RCS理论模型.以矩形金属平板为例,分别计算了雷达静止和三种运动方式下的近场RCS曲线.结果表明,雷达的运动状态对目标近场RCS的影响是不容忽视的,也是比较复杂的. 相似文献
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主动数据库的规则终止性分析 总被引:1,自引:1,他引:1
提出一种基于进化图的规则终止性静态分析的方法,全面考虑了触发图、活化图和惰化图。这种基于进化图的分析方法比传统基于图的分析方法分析更为精确,之后提出了规则终止性分析算法并证明了其正确性。 相似文献
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Warren WC Hillier LW Marshall Graves JA Birney E Ponting CP Grützner F Belov K Miller W Clarke L Chinwalla AT Yang SP Heger A Locke DP Miethke P Waters PD Veyrunes F Fulton L Fulton B Graves T Wallis J Puente XS López-Otín C Ordóñez GR Eichler EE Chen L Cheng Z Deakin JE Alsop A Thompson K Kirby P Papenfuss AT Wakefield MJ Olender T Lancet D Huttley GA Smit AF Pask A Temple-Smith P Batzer MA Walker JA Konkel MK Harris RS Whittington CM Wong ES Gemmell NJ Buschiazzo E Vargas Jentzsch IM Merkel A 《Nature》2008,453(7192):175-183
We present a draft genome sequence of the platypus, Ornithorhynchus anatinus. This monotreme exhibits a fascinating combination of reptilian and mammalian characters. For example, platypuses have a coat of fur adapted to an aquatic lifestyle; platypus females lactate, yet lay eggs; and males are equipped with venom similar to that of reptiles. Analysis of the first monotreme genome aligned these features with genetic innovations. We find that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypus biology. Expansions of protein, non-protein-coding RNA and microRNA families, as well as repeat elements, are identified. Sequencing of this genome now provides a valuable resource for deep mammalian comparative analyses, as well as for monotreme biology and conservation. 相似文献
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用双向电泳研究里氏木霉在4种
碳源条件下分泌组中纤维降解酶的分布情况。结果表明:在以甘油或葡萄糖为碳源时仅CBHⅡ、AxeI和BXL 3种纤维降解酶有微量表达。在以纤
维二糖为碳源时检测到较高表达水平的CBHⅠ、CBHⅡ、EGⅠ、EGⅢ、BXL、AxeⅠ和AglⅠ。纤维素纸浆可诱导CBHⅠ、CBHⅡ、EGⅠ、EGⅡ、EGⅢ
、EGⅣ、ManⅠ、ManⅡ、AxeⅠ、BXL和AglⅠ等11种纤维降解酶的大量表达,表达量总和占总分泌组的61%。纤维素诱导的纤维降解酶组分情况
和纤维二糖条件相似,但表达量和酶活性都有显著上升。 相似文献