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131.
132.
ABSTRACT Two horses were infected with distinct non-tsetse transmitted Trypanozoon Venezuelan stocks, namely TeAp-N/D1 Trypanosoma equiperdum and TeAp-El Frio01 Trypanosoma evansi. Preceding reports have revealed that a 64-kDa antigenic glycopolypeptide (p64), which is the soluble form of the predominant variant surface glycoprotein from TeAp-N/D1 T. equiperdum, can be used as a good antigen for immunodiagnosis of animal trypanosomosis. Here, the course of the experimental acute infection in both horses was monitored by evaluating total anti-p64 IgG and particular anti-p64 γ-specific IgG and μ-specific IgM isotypes in sera using indirect enzyme-linked immunosorbent assays. Both equines showed a maximum of whole anti-p64 antibody generation, which dropped to readings below the maximum but always above the positive cutoff point. Levels of specific IgG and IgM isotypes oscillated throughout the course of the experiments. Essentially, the γ-specific IgG response remained very close to the cutoff point, whereas the μ-specific IgM response displayed values that were mostly above the positive cutoff point, showing a major peak that coincided with the maximum of complete anti-p64 IgG production. These results showed that horses infected with non-tsetse transmitted Trypanozoon parasites developed an immune reaction characterized by a dominant IgM generation against the p64 antigen. 相似文献
133.
134.
脑电(Electroencephalography, EEG)和功能磁共振(Functional magnetic resonance imaging, fMRI)技术的结合,可以实现两者优势的互补,获得更加合理的源定位结果.本文报道的是一种将fMRI先验信息结合到脑电源定位中的新方法.在该方法中,先利用SPM方法计算获得fMRI的统计映射参数,然后将基于计算获得的统计参数构造的权矩阵结合到FOCUSS的迭代过程中,对脑电的反演提供具有fMRI先验空间位置信息的约束,提高脑电的源空间定位精度,从而获得更加合理的定位结果.通过对一形状知觉实验fMRI和脑电数据的结合定位分析,结果初步证实了改进方法能获得和生理更加一致的结果. 相似文献
135.
Helen He Ester Del Duca Aisleen Diaz Hyun Je Kim Jesús Gay-Mimbrera Ning Zhang Jianni Wu Jessica Beaziz Yeriel Estrada James G. Krueger Ana B. Pavel Juan Ruano Emma Guttman-Yassky 《The Journal of allergy and clinical immunology》2021,147(4):1369-1380
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136.
D G Haegert 《Journal of immunological methods》1985,82(2):261-266
Under optimal test conditions significantly more freshly isolated human T cells reacted with OKT4, OKT8, OKM1 and OKB7 monoclonal antibodies (Mabs) in the indirect antiglobulin rosetting reaction (IARR) than by indirect immunofluorescence. Rabbit erythrocytes (E) coated with anti-mouse immunoglobulin were more sensitive indicator cells in the IARR than similarly coated sheep E. Treatment of T cells with neuraminidase further enhanced T cell reactivity in the IARR with each Mab so that an average of 60% or more of T cells were T4+, T8+ and M1+ and at least 40% had the T4+ T8+ phenotype. The various findings suggest that the rosette assay detects determinants on T cells that are expressed below the detection threshold of immunofluorescence. Moreover, these findings indicate that the cellular specificities of a particular Mab may change when one assay system is substituted for another or when the protocol of a particular assay is altered. 相似文献
137.
Alireza Rezania Carson H. Thomas Kevin E. Healy 《Annals of biomedical engineering》1997,25(1):190-203
Patterned surfaces with alternating regions of amino silanes [N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane (EDS)] and alkyl silanes [dimethyldichlorosilane (DMS)] have been used to alter
the kinetics of spatial distribution of cellsin vitro. In particular, we have previously observed the preferential spatial distribution of bone cells on the EDS regions of EDS/DMS
patterned surfaces (10). In this study, we examined whether the mechanism of spatial distribution of cells on the EDS regions
was adhesion mediated. Homogeneous layers of EDS and DMS were immobilized on quartz substrates and characterized by contact
angle, X-ray photoelectron spectroscopy, and spectroscopic ellipsometry. The strength of bone cell attachment to the modified
substrates was examined using a radial flow apparatus, within either 20 min or 2 hr of cell incubation in the presence of
serum. A Weibull distribution was chosen to characterize the strength of cell-substratum adhesion. Within 20 min of cell exposure,
the strength of adhesion was significantly larger on EDS and clean surfaces, compared with DMS surfaces (p<0.0001). Within 2 hr of cell incubation, there was no statistical difference between the strength of cell adhesion to EDS,
DMS, and clean surfaces. The results of this study suggest that the surface chemistry mediates adhesion-based spatial cell
arrangement through a layer of adsorbed serum proteins. 相似文献
138.
目的 应用新型杆状病毒表达系统快速构建含有HBsAg基因的重组杆状病毒,高效表达HBsAg,为HBV诊断试剂、疫苗及治疗研究提供依据。方法 构建含有HBsAg基因的供体质粒pFB-BS,转化Bac-to-Bac杆状病毒表达试剂盒中的DH10Bac致敏菌,利用其含有的细菌Tn7转座繁忙将HBsAg基因重组至穿梭质粒Bacmid上,快速筛选出含有HBsAg基因的重组杆状病毒。结果 此重组病毒能在昆虫细 相似文献
139.
利用脉搏波特征参数连续测量血压的方法研究 总被引:11,自引:0,他引:11
通过研究血压与脉搏波特征参数的关系,提出了一个选择多个与血压相关的脉搏波特征参数,通过回归分析建立适合不同人的特征方程,进行血压的连续测量的新方法,为了验证测量结果的准确性;研制了张力计。实验结果表明:该方法具有较高的测量精度,可以应用于临床危重病人的血压监护和一般医学研究中,经过进一步地改进和完善后可应用于载人航天和日常动态环境。 相似文献
140.
Influence of vascular parameters on the effectiveness of intra-aortic balloon pumping: A model study
The intra-aortic balloon pump has been widely used as a temporary heart-assist device. In this investigation, a nonlinear
mathematical model of the arterial system and intra-aortic balloon pump was studied analytically. Thus, the influences of
a number of vascular parameters on the effectiveness of intra-aortic balloon pumping (IABP) were determined. The effects of
changes in vascular parameters of the model on a number of performance indexes were investigated. These performance indexes
(aortic mean diastolic pressure, aortic end diastolic pressure, cardiac output, coronary flow and phase differences between
the fundamental Fourier components of aortic root pressure and flow) were used as the criterion for an evaluation of the effectiveness
of the assist pump. The following vascular parameters were perturbed by four steps (±10%, ±20%) from the values in the standard
model: heart rate, peripheral resistance, left ventricular pressure, aortic elastance, aortic radius, arterial wall thickness,
and aortic length. This model was evaluated for a wide range of balloon-pump phase-control settings (assisted case) and for
the unassisted case (when the pump is disabled). It is concluded that changes in heart rate, peripheral resistance and left
ventricular pressure cause the most significant changes in pump performance.
Dr. Ohley is with the Datascope Corporation
Dr. Kao is with the Technicare Corporation 相似文献