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1.
Matsuura K Ikoma S Sugiyama M Funauchi M Sinohara H 《Applied biochemistry and biotechnology》2000,83(1-3):107-114
Polyclonal Immunoglobulin (Ig) G from patients with rheumatoid arthritis (RA) and healthy subjects hydrolyzed carbobenzoxy−Val−Gly−Arg
p-nitroanilide and D−Pro−Phe−Arg p-nitroanilide. RA IgG exhibited higher activity against the former substrate, but not the latter. On the other hand, RA IgG
showed reduced activity against D−Pro−Phe−Arg methylcoumarinamide, when compared with those of the healthy controls. These
results suggest that RA IgGs differ from normal IgGs in the substrate specificity of amidase activity. Preliminary studies
have shown that two out of three RA IgG samples cleaved a pentapeptide—Gln−Arg−Arg−Arg−Ala−Ala— which is assumed to be associated
with the risk of developing RA (Gregersen, P. K. et al. (1987), Arthritis Rheum.
30, 1205–1213). By contrast, virtually no cleavage of the same peptide was observed with IgG from healthy controls. A peptide
analog, Gln−Arg−Arg−Trp−Ala, was not cleaved at all by any IgGs examined either from RA patients or healthy controls. 相似文献
2.
Buneva VN Kanyshkova TG Vlassov AV Semenov DV Khlimankov DYu Breusova LR Nevinsky GA 《Applied biochemistry and biotechnology》1998,75(1):63-76
Various catalytically active antibodies (Abs), or abzymes, have been detected recently in the sera of patients with autoimmune
pathologies, in whom their presence is probably associated with autoimmunization. Normal humans are generally not considered
to have abzymes, since no obvious immunizing factors are present. Here is shown by different methods that IgG from the milk
of normal females possesses both DNase and RNase activities. The activities were also present in the IgG F(ab′)2 and Fab fragments.
Affinity modification of IgG by the chemically reactive derivative of an oligonucleotide led to preferential modification
of the L chain of IgG. After separation of the subunits by sodium dodecyl sulfate electrophoresis in a gel containing DNA,
an in-gel assay showed DNase activity in the L chain. The L chain separated by affinity chromatography on DNA-cellulose was
catalytically active. These findings speak in favor of the generation of cat alytic Abs by the immune system of healthy mothers.
It is known that the treatment of adults with DNases and RNases offers protection from viral and bacterial diseases. Since
breast milk protects the infants from infec tions until the immune system is developed, this raises the possibility that catalytic
Abs like nucleases, may possess a protective role. 相似文献
3.
Summary A high-performance liquid gel-permeation chromatographic method is described for the determination of human serum immunoglobulin G (IgG) by separating the fluorescent immuno complex from the free fluorescence-labeled antibody. Fluorescence-labeled antibody used in this study was fluorescein isothiocyanate (FITC)-labeled Fab fragment goat anti-human IgG (anti-IgG Fab). Immuno complexes and antibody of different molecular sizes can be separated. FITC-labeled anti-IgG Fab was added to the serum and the mixture is passed through the column. An immuno complex separates as well-delineated peak in the column void volume, and was measured by the fluorescence of the column eluate (Ex=490nm, Em=520nm). The total analysis time for a serum sample was approximately 15min. The minimum detection limit was 25 mg/dl. The relative standard deviation was below 2% (peak area). The results of the HPL-GPC analysis correlate well with those obtained by laser nephelometric assay (r=0.992). 相似文献
4.
5.
目的:探讨低铅水平对IgA、 IgG 、 IgM、 C3、 C4、 B淋巴细胞的影响。方法用石墨炉原子吸收光谱法对39名印刷印染工龄5年以上工人进行血铅测定,另选择距污染源较远且无水系联系的,不受工业污染的,从未接触过重金属的为对照组,分别对两组用免疫比浊法进行( IgA、IgG、 IgM、 C3和C4)5项测定,流式细胞仪检测血B淋巴细胞水平,全自动生化仪检测白细胞数、总淋巴细胞绝对数和百分比。结果高低铅两组IgA、 IgG 、 IgM、 C3水平比较差异有统计学意义(P<0.05),白细胞总数、淋巴细胞百分比均低于低铅组(P<0.05),总淋巴细胞百分比和NK淋巴细胞亚群的绝对数和百分比却低于低铅组( P<0.05)。结论高血铅对体液免疫功能有一定的影响。 相似文献
6.
Dagmar Medková Mariya Ptashnyk Werner Varnhorn 《Mathematical Methods in the Applied Sciences》2015,38(17):3968-3979
With methods of potential theory, we develop a representation of a solution of the coupled Stokes–Darcy model in a Lipschitz domain for boundary data in H?1/2. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
7.
In this paper, applying both Lyapunov function techniques and monotone iterative techniques, we establish new sufficient conditions under which the infected equilibrium of an HIV pathogenesis model with cure rate is globally asymptotically stable. By giving an explicit expression for eventual lower bound of the concentration of susceptible CD4+ T cells, we establish an affirmative partial answer to the numerical simulations investigated in the recent paper [Liu, Wang, Hu and Ma, Global stability of an HIV pathogenesis model with cure rate, Nonlinear Analysis RWA (2011) 12 : 2947–2961]. Our monotone iterative techniques are applicable for the small and large growth rate in logistic functions for the proliferation rate of healthy and infected CD4+ T cells. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
Matti Schneider 《Mathematical Methods in the Applied Sciences》2015,38(13):2761-2778
The FFT‐based homogenization method of Moulinec–Suquet has recently attracted attention because of its wide range of applicability and short computational time. In this article, we deduce an optimal a priori error estimate for the homogenization method of Moulinec–Suquet, which can be interpreted as a spectral collocation method. Such methods are well‐known to converge for sufficiently smooth coefficients. We extend this result to rough coefficients. More precisely, we prove convergence of the fields involved for Riemann‐integrable coercive coefficients without the need for an a priori regularization. We show that our L2 estimates are optimal and extend to mildly nonlinear situations and Lp estimates for p in the vicinity of 2. The results carry over to the case of scalar elliptic and curl ? curl‐type equations, encountered, for instance, in stationary electromagnetism. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
9.
Infinitely many homoclinic orbits for a class of second‐order damped differential equations 下载免费PDF全文
We investigate the existence and multiplicity of homoclinic orbits for the second‐order damped differential equations For Equation 1 where L(t) and W(t,u) are neither autonomous nor periodic in t. Under certain assumptions on g, L, and W, we get infinitely many homoclinic orbits for superquadratic, subquadratic and concave–convex nonlinearities cases by using fountain theorem and dual fountain theorem in critical point theory. These results generalize and improve some existing results in the literature. Copyright © 2015 JohnWiley & Sons, Ltd. 相似文献
10.
Hassan A. Zedan M. Alghamdi Seham Sh. Tantawy 《Mathematical Methods in the Applied Sciences》2015,38(17):4357-4364
We study in this paper the Q‐symmetry and conditional Q‐symmetries of Drinfel'd–Sokolov–Wilson equations. The solutions which we obtain in this paper take the form of convergent power series with easily computable components. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献