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21.
Interleukin-1 Hyperproduction by In Vitro Activated Peripheral Macrophages from Cerebellar Mutant Mice 总被引:3,自引:1,他引:2
B. Kopmels E. E. Wollman J. M. Guastavino N. Delhaye-Bouchaud† D. Fradelizi J. Mariani† 《Journal of neurochemistry》1990,55(6):1980-1985
Several mutations in mice produce complex patterns of neuronal degeneration of the cerebellum and of its afferent pathways. In the staggerer (sg/sg) mutant, atrophy of the lymphoid organs and immunological abnormalities have been described. To search for a possible link between the neurological and the immune disorders in this mutant, we studied the production by its peripheral macrophages of interleukin-1 (IL-1), which roles in both immune and nervous systems are well established. Suspensions of peritoneal and/or spleen macrophages from mutants and their appropriate controls were stimulated in vitro by lipopolysaccharide. Northern and dot blots, performed with murine IL-1 cDNA probes, revealed a clear-cut hyperexpression of IL-1 mRNA in staggerer macrophages. An IL-1 bioassay using the IL-1-responsive D10.G4 cell line also revealed a sixfold increase of IL-1 activity in the macrophage supernatants of staggerer mutant mice. The hyperproduction was found in 3-week to 1-year-old staggerer and also in heterozygous (+/sg) mice. A similar phenomenon existed in cerebellar mutants lurcher, Purkinje cell degeneration (pcd), and to a lesser extent reeler and wobbler, but was absent in the neurological mutants weaver, jimpy, and motor end plate disease (medH). These observations establish that in several point mutations in mice, central nervous degeneration is associated with dysregulation of IL-1 production by peripheral macrophages. 相似文献
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Peeter Kangur 《Hydrobiologia》1996,338(1-3):173-177
The population of bream in L. Peipsi was studied with respect to age, growth rate, condition factor (according to Fulton) and length-weight relationship in 1994. That autumn the bream population in L. Peipsi consisted of fishes aged from 0+ to 15+. During the first year bream reached an average body length of 7.9 cm (the commercial legal size (30 cm) was usually attained by the end of the 5th–6th year. The condition of bream in this lake was above the average of Estonian lakes. The relatively good growth rate and condition of bream in the lake indicates that the waterbody is appropriate for this fish. 相似文献
24.
Dominique Le Grand Michel Solsona Renate Rosengarten francois Poumarat 《FEMS microbiology letters》1996,144(2-3):267-275
Abstract The variability of predominant Mycoplasma bovis surface antigens in the presence of specific immune pressure was analyzed in an in vitro assay to determine if M. bovis could escape immune destruction. We have shown that serum antibodies from immunized or experimentally infected calves and monoclonal antibodies which specifically react with previously characterized or as yet undefined major M. bovis membrane surface proteins cause repression of expression or shortening of the target protein, or induce switching to expression of an antigenically distinct variant protein. We have further demonstrated that removal of the inducing antibody results in reversion to the original phenotype. These results suggest that the level of expression and the length of M. bovis surface antigens in the host is modulated by cognate antibodies. According to the surface antigenic variation systems, random selection of preexisting variants resistant to antibody-mediated inhibition or direct regulation of gene expression may be means by which this organism evades host immune defences. 相似文献
25.
J. Des Forts 《International Journal of Anthropology》1996,11(2-4):123-136
For millenaria, maternal mortality has been considered as a fatality inherent to women's condition. Thanks to the progress of the obstetric technology, the world M.M.R. fell from 2.000 to 400 per 100.000 births during the past 150 years. At the same time women's condition improved chiefly because of a better level of education. Is there any relationship between them: the decrease of Maternal Mortality and the amelioration of women's general status? Or, in other words, can the decrease of Maternal Mortality Rate be considered as an “indicator” of the situation of women? After a historical review of the importance of the maternal mortality drama as it occured in older times before the “obstetric era”, which began with the improvement of the obstetric technology, this paper will present the actual situation of maternal mortality in relation with the obstetric coverage, the female literacy level and some other socio-economic variables, and in relation with the Gross National Product (G.N.P.) as an indicator of governmental interest in the specific female problems of giving-life. 相似文献
26.
Microspore culture is a very important and useful tool in plant breeding for haploid production and has been developed for many years.Brassica campestris (Brassica rapa L. ssp.oleifera) is an important oilseed crop, but it is relatively recalcitrant in tissue culture including microspore culture. The microspore culture in our laboratory is based on the Canadian protocol. Thirty genotypes ofB. campestris were included in this study; twenty produced embryos. The highest yield was 5930 embryos per 100 buds from Canadian genotype Cv-2, this result was one of the best that had been reported in microspore culture inB. campestris. The buds measuring 2.0 mm to 3.9 mm in length responded best to produce embryos, the optimum timing for microspore culture was confirmed to be during the mid-late to very-late uninucleate stage. The buds could be removed from either the main raceme or lateral racemes. Activated charcoal (150 mg l-1) was added to the liquid NLN medium, it promoted embryogenesis significantly; embryo development was faster and the embryo yield was significantly higher than those cultures without activated charcoal. The donor plant condition was considered an important factor influencing embryogenesis; older donor plants (older than five weeks) and a cold treatment are recommended. 相似文献
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28.
应用常规病理、免疫病理及超微病理技术,对33例流行性出血热(EHF)患者皮肤活检标本的病理变化及病毒抗原、免疫复合物进行观察,同时与血清病毒抗原、抗体及循环免疫复合物检出情况进行比较。在23例EHF患者皮肤微血管内皮细胞中检出病毒抗原,部分组织中可同时检出免疫球蛋白及C3,少数组织仅能检出病毒抗原或免疫球蛋白。配对血清小也可检出EHF病毒抗原、抗体及循环免疫复合物。组织及血清免疫复合物形成与血清补体C3水平下降有关,组织内肥大细胞脱颗粒与血清IgE水平升高相关,提示多种变态反应参与了流行性出血热的发病机制。 相似文献
29.
屎克螂适宜的繁殖条件初步研究 总被引:2,自引:0,他引:2
1991—1994年对屎克螂适宜的繁殖条件研究结果:1.土层40cm和60cm的平均温度分别为15.92±6.34℃和15.89±6.08℃;平均土壤含水量分别为26.70±3.74%和23.72±1.88%,使各虫态处于一个几乎恒温恒湿的条件,有利于生长发育与越冬,2.土壤含水量17%、20%、22%、26%和29%,其产卵最多的深度分别在65─70cm,75─80cm,65─80cm,65—80cm和35—50cm,分别占产卵总数的34.16%、42.42%、68.42%、55.40%和90.56%。3.不同土壤的产卵深度,沙壤土以土下45—50cm处最多,占产卵总数的34.78%;沙土以65—85cm最多,占产卵总数的86.67%;粘土以45—60cm最多,占产卵总数的51.11%。 相似文献
30.
在自生异养条件下,旋扭山绿豆根瘤菌MXDI6菌株的氢酶诱导表达受气相、pH值、镍等因子影响:氢酶表达的最适氧浓度为4%,最适氢浓度为15%,二氧化碳没有明显影响;氢酶表达的pH值以5.0—6.0为宜;0.5μmol/LNiCl2明显促进吸氢活性,但镍浓度大于1μmol/L则抑制吸氢活性. 相似文献