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应用免疫PCR法研究抗双链DNA抗体识别的DNA序列 总被引:2,自引:0,他引:2
用1段合成的108bp DNA及免疫PCR法,研究了SLE血清抗双链DNA抗体识别的NDA序列。结果发现;10个长度为108bp序列各异的已知DNA片段,同具有亿万变化的108bpDNA片段库一样,与抗双链DNA抗体有良好反应,其中间25个bp的变异不影响抗体与抗原反应;SLE血清中抗体趋向于易形成非bata-DNA结构的DNA特异结合。 相似文献
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<正>生物体细胞基因组完整性受到诸多因素的威胁,包括DNA复制过程中DNA碱基错配、化学物质产生的碱基加合物(adduct formation)和交叉链(cross-links)、紫外线诱导的碱基损伤、电离辐射导致的DNA单链或双链断裂等。DNA双链断裂(DNAdouble-strand break,DSB)被认为是细胞毒性最强的 相似文献
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应用PCR技术检测血清抗双链DNA抗体 总被引:3,自引:1,他引:2
人工合成一段62核苷酸的核苷酸序列,中间25个核苷酸为随机合成。经PCR扩增后提供一个含有亿万种结构变异DNA片段库供体DNA抗体反应。阳性病人血清沉淀的特异双链DNA片段经PCR扩增后出现特异的阳性扩增区带。结果表明,40例SLE血清经PCR检测32例为阳性,而Farr放免法14例为阳怀,两者之间有显著差异,40例非SLE结缔组织病人血清,两者阳性率分别为7.5%和2.5%,两者比较无明显差异。 相似文献
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不同凋亡水平T细胞来源的ALD-DNA对抗双链DNA抗体产生的影响 总被引:1,自引:0,他引:1
研究不同凋亡水平T细胞来源的ALD-DNA(activated lymphocyte-derived DNA)对抗双链DNA抗体产生的影响。用尼龙毛柱法分离小鼠脾脏T细胞,分别提取不同凋亡水平T细胞的DNA定义为未凋亡ALD-DNA、低凋亡水平ALD-DNA、中凋亡水平ALD-DNA和高凋亡水平ALD-DNA,并免疫同系BALB/c小鼠;用ELISA方法检测血清中IgG类抗双链DNA抗体的水平及其亚型;用考马斯亮蓝法检测免疫小鼠尿蛋白的含量。结果显示,ALD-DNA的凋亡水平与其诱导产生的抗双链DNA抗体水平成正相关,二者的相关系数r=0.852;不同凋亡水平的ALD-DNA诱导的抗双链DNA抗体均以IgG1为主,但IgG2a和IgG2b的水平在高凋亡ALD-DNA免疫组有明显增高;低凋亡ALD-DNA、中凋亡ALD-DNA和高凋亡ALD-DNA免疫小鼠均有显著蛋白尿形成,并且高凋亡ALD-DNA免疫组的尿蛋白含量有明显增高。该结果表明,高凋亡水平的ALD-DNA免疫同系小鼠更易诱导高水平的致病性IgG类抗双链DNA抗体产生,凋亡DNA可能在系统性红斑狼疮(SLE)发生发展过程中发挥了重要作用,这为我们能更加深入的理解SLE的发生机制提供了有力的实验依据。 相似文献
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制备抗双链DNA(dsDNA)单克隆抗体并对其生物学特性进行初步研究。以活化淋巴细胞的DNA为免疫原,常规免疫BALB/c小鼠,采用B淋巴细胞杂交瘤技术制备单克隆抗体;用体内诱生法制备腹水,以间接酶链反应吸附试验(ELISA)法分析抗体的亚类、特异性和亲和力;用免疫荧光法检测抗体的荧光核型;用考马斯亮蓝法检测注入杂交瘤细胞的小鼠的尿蛋白含量。结果显示,成功获得了1株持续稳定分泌抗dsDNA单克隆抗体的杂交瘤细胞株,命名为6C2;该细胞株所分泌的抗体亚类为小鼠IgG2a,能特异性结合dsDNA,亲和力常数为2.67×10~8mol/L,免疫荧光核型为均质型;将6C2细胞注入正常BALB/c小鼠腹腔后,小鼠的尿蛋白含量较对照组明显增高。结果表明,抗dsDNA单克隆抗体6C2是致病性抗体,对于进一步研究抗dsDNA抗体的致病机制具有重要的价值。 相似文献
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目的:探究脊形滤波器结构对质子束流展宽的影响。方法:利用蒙特卡罗程序FLUKA建立质子束流模型,并进行验证。模拟质子束流通过三棱柱型(A型)和金字塔型(B型)两种脊形滤波器,比较使用和不使用脊形滤波器的模拟值:束流前端最大剂量50%到束流末端最大剂量50%的宽度(E50-D50)、束流前端80%到束流末端80%的宽度(E80-D80)及束流末端80%到束流末端20%的宽度(D80-D20)。结果:根据模型计算出的121.1 MeV质子对应的模拟值绘制的积分深度剂量曲线与实际测量的积分深度剂量曲线,E50、E70和D80位置偏差不超过0.06 mm;A型相比B型将E50-D50平均多展宽了0.80 mm,将E80-D80 平均多展宽了0.27 mm,将D80-D20 平均多展宽了0.08 mm。结论:建立的质子束流蒙特卡罗模型合理,三棱柱型(A型)脊形滤波器展宽质子束流的效果更好。 相似文献
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Although variability of anthropometric measures within a population is a well established phenomenon, most biomechanical models
are based on average parameter values. For example, optimisation models for predicting muscle forces from net joint reaction
moments typically use average muscle moment arms. However, understanding the distribution of musculoskeletal morbidity within
a population requires information about the variation of tissue loads within the population. This study investigated the use
of Monte Carlo simulation techniques to predict the statistical distribution of deltoid and rotator cuff muscle forces during
static arm elevation. Muscle moment arms were modelled either as independent random variables or jointly distributed random
variables. Moment arm data was collected on 22 cadaver specimens. The results demonstrated the use of Monte Carlo techniques
to describe the statistical distribution of muscle forces. Although assuming statistically independent moment arms did affect
the statistical distribution shape, that assumption did not affect the median predicted forces. The standard deviations of
muscle forces predicted using Monte Carlo techniques were similar to the standard deviation of muscle force predictions using
the whole sample of specimens. It is concluded that Monte Carlo simulation techniques are a useful tool to analyse the interindividual
variability of rotator cuff muscle forces. 相似文献
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蒙特卡罗技术在辐射剂量学中的应用 总被引:4,自引:1,他引:4
由于蒙特卡罗模拟能够细致地描述粒子在物质中的输运过程,辐射剂量学中的许多问题都可以利用蒙特卡罗技术来解决。本文讨论了蒙特卡罗技术在辐射剂量学中的主要应用方面以及近年来的发展方向,并通过实际的计算结果说明应用该技术能够对辐射剂量学的研究起到非常重要的推动作用。 相似文献
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《Acta biomaterialia》2014,10(2):709-721
Scaffolds for tissue engineering (TE) require the consideration of multiple aspects, including polymeric composition and the structure and mechanical properties of the scaffolds, in order to mimic the native extracellular matrix of the tissue. Electrospun fibers are frequently utilized in TE due to their tunable physical, chemical, and mechanical properties and porosity. The mechanical properties of electrospun scaffolds made from specific polymers are highly dependent on the processing parameters, which can therefore be tuned for particular applications. Fiber diameter and orientation along with polymeric composition are the major factors that determine the elastic modulus of electrospun nano- and microfibers. Here we have developed a neural network model to investigate the simultaneous effects of composition, fiber diameter and fiber orientation of electrospun polycaprolactone/gelatin mats on the elastic modulus of the scaffolds under ambient and simulated physiological conditions. The model generated might assist bioengineers to fabricate electrospun scaffolds with defined fiber diameters, orientations and constituents, thereby replicating the mechanical properties of the native target tissue. 相似文献
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随着生物和光学技术的成熟,近红外荧光成像得到了飞速发展。荧光分子断层成像是以特定波长的光去激发荧光染料,使其吸收入射光,并发出波长长于入射光的近红外荧光。前向问题是进行光学成像研究的关键环节,可以指导实验以及重建算法。本文提出了一种基于Monte Carlo方法的荧光分子断层成像的光子传输模型,重点研究了激发光激发荧光的过程以及光子在生物体内的传播过程,在已知激发光源、传播介质、荧光物质等参数的条件下,得到荧光光子在CCD探测器上的分布情况,并且分别用理论和实验两种方法对算法的仿真结果进行了验证。 相似文献
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Randy K. Avent John D. Charlton H. Troy Nagle Richard N. Johnson 《Annals of biomedical engineering》1987,15(1):79-89
Statistical monitoring techniques like CUSUM, Trigg's tracking signal and EMP filtering have a major advantage over more recent
techniques, such as Kalman filtering, because of their inherent simplicity. In many biomedical applications, such as electronic
implantable devices, these simpler techniques have greater utility because of the reduced requirements on power, logic complexity
and sampling speed. The determination of signal means using some of the earlier techniques are reviewed in this paper, and
a new Monte Carlo based method with greater capability to sparsely sample a waveform and obtain an accurate mean value is
presented. This technique may find widespread use as a trend detection method when reduced power consumption is a requirement. 相似文献