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121.
牛病毒性腹泻——粘膜病是世界性广泛流行的奶牛和肉牛的传染病。其病原为牛病毒性腹泻病毒(BVDV),属于披膜病毒科的瘟病毒属,它的许多生物学特性至今还不很清楚。本试验建立了12株分泌抗BVDV的单克隆抗体(McAb)杂交瘤细胞株,并结合免疫转移电泳法和放射免疫沉淀法,初步研究了BVDV的多肽。  相似文献   
122.
子宫颈糜烂病毒病因的探讨   总被引:17,自引:0,他引:17  
491份宫颈拭子病毒分离结果表明:糜烂宫颈单纯疱疹病毒(HSV)分离阳性率(30.8%)是正常宫颈(2.6%)的11.8倍,用人干扰素治疗一个疗程后,病毒分离率下降至疗前的1/4.36例糜烂宫颈活体组织DNA分子杂交表明,乳头瘤病毒16型(HPV-16)阳性者占52.8和,HPV-18占17.9%,HPV-6B占28.1%,HPV-11占7.7%,251例宫颈糜烂患者经人(?)D型基因工程干扰素双盲对比治疗后,总有效率达93.8%,显效率达60%,分析临床疗效与HSV分离率的变化表明,临床有效病例中有35%(49/140)在治疗后病毒阴转,有57%在疗前疗后均未分离出HSV,有5%在疗前疗后保持阳性不变,有2.9%疗前阴性,疗后阳性,上述结果表明,HSV和HPV与慢性宫颈炎有一定关系。  相似文献   
123.
亚急克病人心肌线粒体内膜电子传递链的琥珀酸氧化酶系,琥珀酸脱氢酶和细胞色素氧化酶活性明显低于对照。H~ -ATP酶的活性及其对寡霉素的敏感性都明显下降。ATP能量化后线粒体膜电位的变化也比对照明显降低。膜脂流动性低于对照。亚急克病人心肌线粒体内观察到较多的电子致密无定形物质,经电镜X射线微区等方法分析,认为这些物质不是Ca_3(PO_4)_2,而可能是一种蛋白质凝聚物。此外,心肌线粒体的硒含量远低于对照,而Ca含量明显高于对照。上述结果都反映亚急克病人心肌线粒体明显损伤。根据克山病患者心肌细胞线粒体结构与功能方面呈现的如此广泛与明显的异常,可将克山病称为“心肌线粒体病(Mitochondrial Cardiomyopathy)”。  相似文献   
124.
We have already developed nine B10.MOL congenic strains carrying H-2 haplotypes derived from Japanese wild mice, Mus musculus molossinus, with the C57BL/10 genetic background. To obtain monoclonal antibodies against the H-2 antigen of the Japanese wild mouse, we carried out cell fusion using spleen cells from the animal immunized with one of the B10.MOL strains, B10.MOL-SGR (H-2 wm7). As a result, 19 hybridomas producing monoclonal antibodies were produced. Analysis with the intro-H-2 recombinants derived from B10.MOL-SGR indicated that 8 of them reacted with the class I and II with the class II molecule. The class I antibodies were tested for their cross -reactivities on wild mice and on the panels of standard inbred and B10.MOL strains. Most of the antibodies reacted with both the Japanese wild mice and the other subspecies, including standard inbred, while two antibodies highly specific for the donor H-2K region reacted with only three wild-derived mice, two M. m. molossinus from Anj o and Shizuoka, Japan, and one M. m. domesticus from Pigeon, Canada. In addition, all of the other four antibodies reactive with the K antigen of B10.MOL-SGR also reacted with the same three wild mice. The wild mice belonging to different subspecies might share very similar H-2K antigenic determinants in spite of their genetic and geographical remoteness.  相似文献   
125.
This paper investigates the problem of spontaneous pattern discrimination by the visual system of the fly. The indicator for discrimination and attractivity of a pattern is the yaw torque of a test fly. It is shown that the pattern discrimination process may be treated as a special (degenerate) case of figureground discrimination which has been described in detail in earlier publications. Decisive for the discrimination process is the fact that pattern discrimination by the fly is mediated by motion detectors which respond not only a pattern velocity but also to structural properties of pattern contrast. This is demonstrated by the transition from the existing twodimensional array of motion detectors to a continuous detector field which enabled us to calculate instantaneous detector responses to instationary pattern motion. The new approach, together with the special theory for figure-ground discrimination, is then applied to predict spontaneous discriminations of onedimensional periodic patterns. It is shown that predictions and experimental results are in good agreement. The second set of discrimination experiments deals with two dimensional dot patterns for which a quantitative theory is not yet available. However, it is shown that the attractivity of a dot pattern crucially depends on both the orientation and the direction of motion relative to the fly's eyes. If the contrast of a moving dot elicits an event in a motion detector which through the detector's time constant leads to an interference with an event received by a preceeding dot, the attractivity of the dot pattern is diminished. In the discussion relations are drawn between the concepts of pattern discrimination in honey bees and the theoretical aspects of discrimination put forward in this paper. It is briefly discussed why a two-dimensional motion detector theory might become the key for an understanding of pattern categories like figural intensity and figural quality.  相似文献   
126.
Antitubulin, phalloidin, and antimyosin were used to study the distribution of microtubules, microfilaments, and myofibrils in cultured adult cardiomyocytes. These cells undergo a stereotypic sequence of morphological change in which myotypic features are lost and then reconstructed during a period of polymorphic growth. Microtubules, though rearranged during these events in culture, are always present in an organized network. Myosin and actin structures, on the other hand, initially degenerate. This initial degeneration is reversed when a cell attaches to the culture substratum. Upon attachment, new microtubules are laid down as a cortical network adjacent to the sarcolemma and, subsequently, as a network in the basal part of the cell. Actin and then myosin filament bundles appear next, in a pattern corresponding to the pattern of the microtubules. Finally, striated myofibrils are formed, first in the central part of the cell, and subsequently in the outgrowing processes of the cell. A mechanism is suggested by which the eventual polymorphic shape of a cell is related to the shape of its initial area of contact with the culture substratum. Finally, a model of myofibrillogenesis is proposed in which microtubules participate in the insertion of myosin among previously formed actin filament bundles to produce myofibrils.  相似文献   
127.
聚乙二醇处理的大豆种子的异柠檬酸裂解酶、苹果酸脱氢酶、过氧化氢酶、超氧物歧化酶、酸性磷酸酶、碱性磷酸酶的活性明显高于受低温吸胀冷害的种子子叶的活性,相关的酶活性协同地增长,而蛋白质的含量没有明显的变化。这些酶活性的提高可能是渗透调控处理对细胞膜系统修补的结果。  相似文献   
128.
寄生于樟、阴香和肉桂等植物上的泽田外担菌和油盘孢属真菌,几十年来分类上存在许多不同看法,或全部归泽田外担菌,或全部归油盘孢属,把此二类不同真菌混淆起来,造成名称混乱。本文通过形态学的研究,表明泽田外担菌与油盘孢属的区别是:泽田外担菌具担子层,担孢子4—8个生担子上,寄主是樟树;而油盘孢属的孢子生菌丝上,形成孢子堆,寄主是阴香和肉桂等植物。  相似文献   
129.
用盒式突变和定点突变对大肠杆菌青霉素G酰化酶α亚基177位ser进行了突变研究,结果发现所挑选的突变体均无酶的活力,这一结果可能可以用来解释Ser 177附近肽段和一些青霉素结合蛋白青霉素结合区在一级结构上保持同源性的原因。  相似文献   
130.
胶乳凝集试验在家蚕浓核病毒检测中的应用   总被引:1,自引:0,他引:1  
郭锡杰  钱元骏 《病毒学报》1989,5(4):388-392
  相似文献   
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