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目的:探究心电RR间期序列的延迟时间的计算方法,并研究RR间期序列的延迟时间与其复杂度及年龄的关系。方法:以年轻(21~34岁)与年老(68~81岁)二组健康人的心电RR间期时间序列为实验数据,采用等概率符号分析方法计算其互信息,再按互信息极小原则确定其延迟时间。结果:年老组的延迟时间明显大于年轻组的(P0.015),并使用统计检验对其延迟时间与近似熵的分析,得出二者呈很强的负相关性(P-0.6)。结论:结果表明,RR间期序列的延迟时间直接反应了心电RR间期序列的复杂性特征,其大小与心率变异活动性和心血管的复杂程度负相关。 相似文献
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房颤(AF)是临床上最常见的一种室上性心律失常,对患者危害大,及时利用医疗手段阻止房颤的发生或复发是房颤防治领域关注的焦点和难点。本文尝试利用4种方法对心电信号RR间期序列进行处理,统计不同指标在房颤发作前和远离房颤发作时期的变化,试图寻找能够预测房颤复发的因子。这4种方法分别是:功率谱分析、近似熵(ApEn)和样本熵(SpEn)分析、递归分析以及时间序列符号化。文中数据来源于阵发性房颤预测数据库。通过支持向量机(SVM)分类,评估4种方法的相关指标对房颤复发的预测效果。结果表明,递归分析中的各项参数综合使用达到的分类效果最佳,针对房颤复发预测能够达到95%的准确率;功率谱分析方法次之,准确率为90%;近似熵和样本熵分析、时间序列符号化的效果则不够理想,准确率均只有70%。本文结果说明,基于RR间期的递归分析和功率谱分析能够有效地评估心房混沌状态,对房颤复发预测有一定的参考价值。 相似文献
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BAO Jia li HU Qiao hong LANG Wen quan GAO Jian qing WU Ping .Clinical Engineering Institute Zhejiang University Hangzhou China .Pharmaceutics Institute Zhejiang University Hangzhou China 《中国生物医学工程学报(英文版)》2000,(2)
INTRODUCTIONWiththedevelopmentofmedicinetechnique,peoplehavebeenrealizedthatoralorinjectionlimitsmanypharmaceuticalsbybiotechnologyfromwidelyusing.Be-causealmostthesedrugsconsistofproteinsorpolypeptideseasydegraded.Trans-dermaldrugdelivery(TDD)providesano… 相似文献
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《生物医学工程学杂志》2005,(Z1)
1 IntroductionThe POT1 (protection of telomeres 1) protein binds the single-stranded overhang at the ends of chromosomes in diverse eukaryocytes. It is essential for chromosome end-protection in the fission yeast Schizosaccharomyces pombe, and it is involved in regulation of telomere length in human cells. Human POT1 had been identified in 2001 year. Its amino terminal is highly conservative in eukaryocytes. Since Pot1 can bind internal loops and directly adjacent DNA-binding sites, it is… 相似文献
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目的:探究信号小波成分中的有用信息,并分析心率随年龄的变化。方法:提出了从小波变换(WT)系数的延时互信息MI得出信号分析指标。以年轻(21~34岁)与年老(68~81岁)二组健康人的心电RR间期时间序列为实验数据,用db4为母小波对RR间隔进行WT,计算出MI的值,并取互信息最大值点与第一个极小值点的连线斜率的绝对值|k|为特征指标。结果:统计检验的结果显示:在不同尺度a=120,a=170,a=10时,小波变换系数的互信息的|k|都是年轻组明显大于年老组(P0.002)。结论:结果表明,RR间期时间序列的小波变换系数的延时互信息可反应心率变异性随年龄而减少。 相似文献
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Ryoko Yamagishi Tomohiko Wakayama Hiroki Nakata Kannika Adthapanyawanich Tewarat Kumchantuek Miyuki Yamamoto Shoichi Iseki 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2014,47(3):95-102
In the major salivary glands of mice, acinar cells in the parotid gland (PG) are known to be the main site for the production of the digestive enzyme α-amylase, whereas α-amylase production in the submandibular gland (SMG) and sublingual gland (SLG), as well as the cell types responsible for α-amylase production, has been less firmly established. To clarify this issue, we examined the expression and localization of both the mRNA and protein of α-amylase in the major salivary glands of male and female mice by quantitative and histochemical methods. α-amylase mRNA levels were higher in the order of PG, SMG, and SLG. No sexual difference was observed in α-amylase mRNA levels in the PG and SLG, whereas α-amylase mRNA levels in the female SMG were approximately 30% those in the male SMG. Using in situ hybridization and immunohistochemistry, signals for α-amylase mRNA and protein were found to be strongly positive in acinar cells of the PG, serous demilune cells of the SLG, and granular convoluted tubule (GCT) cells of the male SMG, weakly positive in seromucous acinar cells of the male and female SMG, and negative in mucous acinar cells of the SLG. These results clarified that α-amylase is produced mainly by GCT cells and partly by acinar cells in the SMG, whereas it is produced exclusively by serous demilune cells in the SLG of mice. 相似文献
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基于RR间期的非线性特征预测房颤终止 总被引:1,自引:1,他引:0
识别和描述房颤有可能自发终止或持续,不仅可以更好地了解心律不齐终止的机制,还可以更有效地治疗持续房颤。本研究从两种非线性分析的角度提取房颤信号RR间期的特征,并预测房颤是否能自发终止。一是计算心电信号RR间期序列的Lempel-Ziv复杂度,二是基于符号动力学将RR间期序列转换成符号串,对符号串编码得到符号码,计算各符号码的发生概率,取符号码110的发生概率和符号码发生概率的香农熵作为RR间期序列的特征参数。基于从RR间期提取的上述三个非线性参数,建立模糊分类器来预测房颤是否能终止。实验研究了一个由Hoher心电信号组成的房颤数据库,它包括一个训练集和两个测试集(A和B)。结果表明:本方法可正确分类90%的测试集A和80%的测试集B,和以前方法相比,预测房颤终止的准确率提高了约10%。可见,本方法对Hoher心电信号预测房颤的自发终止是有效的。 相似文献
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Interpersonal synchrony, the temporal coordination of actions, emotions, thoughts and physiological processes, is a widely studied ubiquitous phenomenon. Research has already established that more synchrony is not always more beneficial, especially in the fields of emotional and physiological synchrony. Despite this fact, the dominant tone in the literature is that behavioral interpersonal synchrony is a pro-social phenomenon, and hence, in social contexts, more behavioral synchrony is generally considered better. In accordance with that tone, the naturally occurring dynamics of moving in and out of synchrony have rarely been studied or considered as an adaptive state. In the present article, we aim to present a new model of interpersonal synchrony, based on the existing literature assessing synchrony as well as the ideas of complex dynamical systems. At the core of our model is the idea that two tendencies exist simultaneously, one to synchronize with others and another to move out of synchrony and act independently. We suggest that an adaptive interpersonal system is a flexible one, able to continuously adjust itself to the social context. We suggest that the concept of meta-stability might be a marker of such a flexible interpersonal system. Moreover, the model considers both behavioral and physiological aspects in order to provide a more extensive account. We present research implications of the model, as well as a demonstration of the model's applicability to data, and provide code researchers can use to analyze their own data in these methods. Finally, we discuss future directions in detail. 相似文献
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SHUANG QUAN LIU YI MOU WU FEI JUN ZHAO TIE BING ZENG WEI GUO YIN Institute of Pathogenic Biology Medical College Nanhua University Hengyang P.R.China 《中华微生物学和免疫学杂志(英文版)》2005,3(1):47-52
ELISA test has been shown to have some advan tages in relation to the tests used for the diagnosisof syphilis because of its easy and quick perfor mance and result readings. With recent develop ment of the gene engineering technology and eluci dation of the whole genome of Nichols strain ofTreponema pallidum, new protein coding openreading frames (ORFs) are available for testing,and the study on the serological tests based on therecombinant protein have been become the focus ofinter… 相似文献
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Becker Y 《Virus genes》2003,26(2):119-130
In 1868, dendritic cells (DCs) were discovered in human skin by Paul Langerhans using gold staining. These cells were named Langerhans cells (LCs) after their discoverer who, due to their dendrites, regarded them as neurons. One hundred and eleven years were to pass until it was discovered that in vertebrates these cells originate in the bone marrow as monocytes. In the 1980s, DC research was mostly carried out on DCs that are present in different tissues of mice and humans. These studies revealed that after interaction with foreign antigens, skin LCs/DCs migrate through the lymph vessels to the draining lymph nodes and induce the two arms of the immune response. The isolation of DCs from tissue cell suspensions opened the way to studies on the cells' surface proteins and their ability to stimulate immune responses. During the 1990s, studies revealed the role of DCs in the activation of naïve T cells in the lymph nodes and the regulatory properties of DCs in lymph nodes, thymus, gut, and spleen.Part A of the review deals with the DC system of human and mice and immunological and regulatory functions of subsets of DCs in the skin with reference to migrating and stationary DCs, as well as the connection between DCs and the nervous system. Furthermore, the origin of both follicular DCs that are present in lymphoid tissues and thymic DCs are discussed. Part B is devoted to virus infections of DCs with an emphasis on infections caused by human herpes viruses. Part C presents the modulation of DC gene expression in response to the influenza virus. Contemporary research focuses on the role of DCs in the immune systems of vertebrates. Moreover, studies are being conducted on the regulatory functions of DCs by tissue cells in different organs of vertebrates. 相似文献
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《Experimental and toxicologic pathology》2014,66(7):333-343
The liver and heart are the major target organs for iron accumulation and iron toxicity in β-thalassemia. To mimic the phenomenon of heavy iron overload resulting from repeated blood transfusions, a total of 180 mg of iron dextran was intraperitoneally injected into C57BL/6J mice (WT) and heterozygous β-globin knockout mice (muβth-3/+, BKO). The effects of deferiprone and deferoxamine in this model were investigated. The iron was distributed homogenously throughout the 4 liver lobes (left, caudate, right and median) and was present in hepatocytes, Kupffer cells and the sinusoidal space. Iron accumulation in phagocytic macrophages, recruitment of hepatic lymphocytes and nucleus membrane degeneration were observed as a result of iron overload in the WT and BKO mice. However, the expansion of hepatic extramedullary hematopoiesis was observed only in the BKO mice with iron overload. In the heart, the iron accumulated in the cardiac interstitium and myocytes, and moderate hypertrophy of the myocardial fibers and cardiac myocyte degeneration were observed. Although the total liver iron was not significantly altered by iron chelation therapy, image analysis demonstrated a difference in the efficacies of two iron chelators. The major site of chelation was the extracellular compartment, but treatment with deferiprone also resulted in intracellular iron chelation. Interestingly, iron chelators reversed the pathological changes resulting from iron overload in WT and BKO mice despite being used for only a short treatment period. We suggest that some of these effects may be secondary to the anti-inflammatory activity of the chelators. 相似文献
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JIAN HONG ZUO LI ZHI TAN CHAO QUN CHEN NING ZHENG DONG XIA BAI CHANG GENG RUAN Institute of Pathogenic Biology Nanhua University Hengyang P. R. China Jiangsu Institute of Hematology Suzhou P. R. China 《中华微生物学和免疫学杂志(英文版)》2006,4(1):23-29
Chlamydia trachomatis outer membrane protein 2 (Ctomp2) is a major immunogen in chlamydial infections and a highly genus-conserved structural protein of all Chlamydia species . To purify the protein and to prepare monoclonal antibodies (mAbs) against it, the recombinant protein was induced by IPTG, which was confirmed by SDS-PAGE and purified by means of a Ni2 -charged resin column. The denatured protein was refolded in the GSH-GSSH buffer gradually and identified by Western blotting. Then the BALB/c mice were immunized with the recombinant protein to prepare the mAb against Ctomp2. The obtained mAbs were characterized. Genital specimens were tested with indirect ELISA mostly made of the mAb and cell culture in 84 patients with genital symptoms. The results showed that high-level expression of the recombinant protein was achieved, which existed as inclusion body and amounted to 38 % of total bacterium protein. A mAb against Ctomp2 was obtained. It belongs to IgG 2b. The titers were as high as 1:40 000. The Western blotting showed that the mAb only reacted with the recombinant protein. It had no crossing reactions against E. coli, N. gonorhoea, M. hominis, U. urealyticum and M. penetrans . It had high specifity. In comparison with gold standard test-cell culture, the sensitivities, specificities, positive predictive values and negative predictive values of indirect ELISA were 95.24%, 100%, 100% and 98.44%, respectively. The above-mentioned research work contributed not only to the further study of the structure and function of this protein , but also to the establishment of the method for its clinical application, for it had not been reported before. 相似文献
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《生物医学工程学杂志》2005,(Z1)
1 IntroductionPhysiological effects of estrogen on myocardium are mediated by two intracellular estrogen receptors (ER), alpha (ERα) and beta (ERβ). Their role in cardiovascular physiology is not well understood. For this reason,we investigated the expressions of ERα and ERβ in the development and maturation of rat heart.2 Materials and Methods2.1 Experimental animals The study on changes of ERs was performed in six newborn rats with both sexes and six adult female Wistar rats respedively.2.2 Semiquantitati... 相似文献
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Belogolovskaya EG Oreshchenko AV Durnev AD Seredenin SB Litvinova EV Zubtsov YN 《Bulletin of experimental biology and medicine》2000,130(11):1102-1105
Antimutagenic effects of combination of aspartame (0.4 and 4 mg/kg) and -carotene (0.15-15 mg/kg) were studied by estimation of chromosome aberrations in bone marrow cells of C57Bl/6 mice. Single and 5-day treatment with this combination decreased the clastogenic effects of dioxidine and cyclophosphamide and produced a more potent and universal antimutagenic effect than its constituents. 相似文献