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21.
从3例急性成人腹泻患者粪便中,经电镜观察,成人腹泻轮状病毒—酶联免疫吸附试验(ADRV-ELISA)、普通轮状病毒—酶联免疫吸附试验(Rota-ELISA),猪抗C型(组)轮状病毒和鸡抗D型(组)轮状病毒血清分别与本病毒的免疫电镜试验以及RNA电泳等实验结果,发现了一种新轮状病毒,该病毒的形态结构与普通轮状病毒(Rotavirus)、成人腹泻论状病毒(Adult Diarrhoea Rotavirus,简称ADRV)极为相似,但抗原性与普通轮状病毒(A组),成人腹泻轮状病毒(B组),C型轮状病毒(C组),D型轮状病毒(D组)显然无关。基因分析表明,该病毒基因组由11个双链RNA片段组成,但其RNA电泳图型具有独自的特点,与目前公认的A组、B组、C组、D组论状病毒韵RNA电泳图型均不同,免疫电镜证实,该病毒能被人恢复期血清所凝集,表明该病毒可能是腹泻病人的病因。 相似文献
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Changes with time in the distribution of virus and PR protein around single local lesions of TMV infected tobacco 总被引:1,自引:0,他引:1
Summary ELISA was used to determine PR la protein and TMV accumulation in local necrotic lesions produced on salicylic acid and water sprayed Nicotiana tabacum cv Xanthi-nc leaves. The amount of PR la protein produced is the result of an interaction between the salicylic acid treatment and lesion growth. The implication of these observations for experiments investigating the relationship between PR proteins and resistance are discussed.The distribution of TMV and PR la protein in and around single local necrotic lesions up to 14 days after inoculation was measured by ELISA. The highest concentration of TMV was in the centre of the lesion and decreased rapidly with distance from the centre. In contrast there was very little PR la protein in the centre of the lesion, the largest amounts were just outside the centre, and the concentration then decreased with distance from the centre. This is the distribution that might be expected for a substance closely associated with the restriction of virus spread. 相似文献
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W.H.R. Langridge 《Journal of invertebrate pathology》1983,42(1):77-82
The titer of Amsacta entomopoxvirus (EPV) protein detected in murine L-929 cells by enzyme-linked immunosorbent assay (ELISA) decreased to within preimmune serum levels by 24 hr after inoculation of the virus which indicates that Amsacta EPV structural protein biosynthesis does not occur in the vertebrate cell line. A viral-induced protein of approximately 100,000 Mr was detected by [35S]methionine incorporation 4 hr after inoculation of Tn-368 cells with Amsacta EPV. Biosynthesis of protein which reacted with vaccina antiserum was detected in Estigmene acrea (BTI-EAA) cells by ELISA 10 hr after inoculation with 10 PFU of virus per cell. The amount of putative vaccinia structural protein detected in BTI-EAA cells increased approximately twofold by 70 hr after virus inoculation. No increase in vaccinia structural protein biosynthesis was detected in BTI-EAA cells inoculated with vaccinia virus previously inactivated by heat and UV light. 相似文献
24.
Peggy Keeling Keith Johnson Daryl Sas Kathleen Klukas Peter Donahue Ross Johnson 《The Journal of membrane biology》1983,74(3):217-228
Summary The major membrane protein of the bovine lens fiber cell is a 26-kilodalton (kD) protein (MP26), which appears to be a component
of the extensive junctional specializations found in these cells. To examine the arrangement of MP26 within the junctional
membranes, various proteases were incubated with fiber cell membranes that had been isolated with or without urea and/or detergents.
These membranes were analyzed with electron microscopy and SDS-PAGE to determine whether the junctional specializations or
the proteins were altered by proteolysis. Microscopy revealed no obvious structural changes. Electrophoresis showed that chymotrypsin,
papain, and trypsin degraded MP26 to 21–22 kD species. A variety of protease treatments, including overnight digestions, failed
to generate additional proteolysis. Regions on MP26 which were sensitive to these three proteases overlapped. Smaller peptides
were cleaved from MP26 with V8 protease and carboxypptidases A and B. Protein domains cleaved by these proteases also overlapped
with regions sensitive to chymotrypsin, papain, and trypsin. Specific inhibition of the carboxypeptidases suggested that cleavage
obtained with these preparations was not likely due to contaminating endoproteases. Since antibodies are not thought to readily
penetrate the 2–3 nm extracellular gap in the fiber cell junctions, antibodies to MP26 were used to analyze the location of
the protease-sensitive domains. Antisera were applied to control (26 kD) and proteolyzed (22 kD) membranes, with binding being
evaluated by means of ELISA reactions on intact membranes. Antibody labeling was also done following SDS-PAGE and transfer
to derivatized paper. Both assays showed a significant decrease in binding following proteolysis, with the 22 kD product showing
no reaction with the anti-MP26 sera. These investigations suggest that MP26 is arranged with approximately fourfifths of the
primary sequence “protected” by the lipid bilayer and the narrow extracellular gap. One-fifth of the molecule, including the
C-terminus, appears to be exposed on the cytoplasmic side of the membrane. 相似文献
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本文以抗人C_(?)的羊IgG为包被抗体,以HRP-HBs抗体为指示抗体,建立了可检测激活补体类HBsAg循环免疫复合物(HBsAg/C3-CIC)的C_3捕捉法酶联免疫吸附试验。检测了236例六种类型临床诊断为乙型肝炎的病人血清标本,其阳性率分别为:无症状携带者(ASC)12.9%(4/31),急性肝炎(AH)36.7%(22/60),慢性迁延性肝炎(CPH)33.3%(7/21),慢性活动性肝炎(CAH)59.6%(34/57),重型肝炎(SH)77.8%(14/18),肝炎后肝硬化(PLC)67.3%(33/49),阳性率与肝损严重程度明显相关(P<0.01)。认为HBs-Ag/C3-CIC可能在乙型肝炎病毒引起的慢性活动性肝炎、重型肝炎和肝炎后肝硬化的发病过程中起重要作用,并可作为乙型肝炎的诊断、临床分型和预后判断的指标之一。 相似文献
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Shoot elongation in many coniferous species is predetermined during bud formation the year before the shoot extends. This implies that formation of the primordial shoot within the bud is the primary event in annual shoot growth. Hormonal factors regulating bud formation are consequently of utmost importance. We followed the levels of the endogenous cytokinins zeatin riboside (ZR) and isopentenyladenosine (iPA) in terminal buds, whorl buds and lower lateral buds of the uppermost current-year whorl shoots of 15- to 20-year-old trees of Norway spruce [ Picea abies (L.) Karst.] from June to September. Cytokinins were isolated with affinity chromatography columns, purified by high performance liquid chromatography, and quantified by ELISA. The level of ZR was low in June but increased gradually in all buds until September. Throughout the measurement period, the ZR level was highest in terminal buds and lowest in the scattered lateral, buds, with the whorl buds intermediate. The level of iPA peaked in July and decreased later without any consistent differences among the three classes of buds. The development of different kinds of buds was followed by scanning electron microscopy. We found that bud growth was greatest during August and September. The final size of primordial shoots within the buds varied considerably and the weight of the terminal bud was three times that of the whorl buds and more than five times that of the other lateral buds.
We conclude that the increase in ZR level during the period of active bud development is indicative of the importance of cytokinin for this process. Furthermore, the positive correlation between the level of ZR and bud growth during the period of predetermination of next year's branch growth suggests that this hormone indirectly controls the form of single branches in the spruce tree. 相似文献
We conclude that the increase in ZR level during the period of active bud development is indicative of the importance of cytokinin for this process. Furthermore, the positive correlation between the level of ZR and bud growth during the period of predetermination of next year's branch growth suggests that this hormone indirectly controls the form of single branches in the spruce tree. 相似文献