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101.
Each of the known classes of mammalian glycosaminoglycans, with the exception of keratan sulphate, was found in cerebral cortex samples from patients with Alzheimer-type dementia and age-matched controls. These molecules were quantitated, after electrophoresis and staining with Alcian Blue dye, by scanning densitometry. No significant differences were found between the mean levels of each of the above glycosaminoglycans in frontal cortex from patients with dementia compared with controls. An increase (26%; p less than 0.05) in the mean level of hyaluronate, but not of other glycosaminoglycans, was found in temporal cortex samples. On the other hand, the uronic acid content of hyaluronate degradation products following Streptomyces hyaluronidase treatment of brain glycosaminoglycans did not reveal any statistically significant changes in Alzheimer's disease. HPLC of disaccharide products from Arthrobacter chondroitinase AC digests did not reveal any significant changes in sulphate substitution of chondroitin sulphate in Alzheimer brain. 相似文献
102.
Ahmed M. Abouzid Thomas Frischmuth Holger Jeske 《Molecular & general genetics : MGG》1988,212(2):252-258
Summary The putative replicative form of the abutilon mosaic virus (AbMV), a geminivirus, was purified from infected plants. It was shown to consist of a bipartite genome of 2660 and 2640 bp. This double-stranded DNA has a closed or relaxed circular conformation and part of it is packed in nucleoprotein complexes with a chromatin-like structure. Similarities between the geminiviruses and the animal simian virus 40 are discussed against this back-ground.Cloning was performed under L2/B1 conditions according to the licence of the ZKBS 1526/1This article is based on a doctoral study by A.A. and T.F. in the Faculty of Biology, University of Hamburg 相似文献
103.
Summary Susceptibility toPhomopsis stalk disease ofPlantago lanceolata genotypes, sampled in three different populations with a variable degree of infection by the fungusPhomopsis subordinaria, was determined under greenhouse conditions. Susceptibility of the host varied within, but not among populations. No relationship
between the intensity of the disease in the field and the mean susceptibility of the host genotypes sampled at those locations
could be established. Host susceptibility appeared to be composed of the host genotypes sampled at those locations could be
established. Host susceptibility appeared to be composed of different (uncorrelated) plant characteristics. Determining whether
host genotypes are highly or slightly susceptible can only be achieved by field trials, where the plants are exposed to the
whole set of disease inducing factors. The relevance of host susceptibility to the intensity of disease in the field is discussed
in relation to the variation in pathogenicity of the fungus and the variation in environmental factors prevailing inP. lanceolata populations underP. subordinaria pathogen pressure.
Grassland Species Research Group Number 123 相似文献
104.
105.
106.
1985年4~10月与1986年6~8月,在贵州省沿河县的纸坊村和崔家坨村先后发生了病因不明的传染病。纸坊村约有1/5的村民发病,病死率为12%,崔家坨村有1/10的村民发病,病死率高达30%。发病波及各年龄组,以青壮年为多,有家庭集聚现象。 本病起病急,轻症者只有头晕、乏力、肌痛、多汗、心悸伴以低热,有的初期有短暂的腹泻。重症者有高热(40℃以上)、大汗、心悸、游走性肌肉痉挛伴有明显疼痛和触痛,以腰骶部及四肢肌肉为好发部位。病人烦燥不安,2~5天内死亡。经实验室检查,排除了食物中毒、农药中毒、钩端螺旋体病和弓形体感染。从病人和接触者的粪便中分离到9株病毒,性状一致,为RNA型25nm的球形颗粒,耐酸,耐乙醚,能凝集人“O”型血球。经血清学鉴定为ECHO3型病毒。16份病人双份血清的检测结果表明,恢复期血清对该病毒中和抗体有4倍以上升高者共8例(纸坊村和崔家坨各4例)。病人单份血清也都有较高的抗体。有理由认为两年中先后在两个村庄发生的传染病与ECHO3型病毒有密切关系。查阅文献,尚未见有关ECHO3型病毒引起以肌痛、游走性肌痉挛为特征的疾病的报道。 相似文献
107.
108.
流行性出血热病毒R22株cDNA克隆及其特异性鉴定 总被引:3,自引:0,他引:3
用家鼠型流行性出血热病毒R22株RNA,经polyA接尾,以Oligo-dT做引物,合成cDNA。用pUC18为载体转染E.coli Mc1061,建立cDNA克隆。再经菌落杂交,选择病毒特异性的5个阳性克隆制成缺口翻译探针,与病毒RNA3个片段进行反杂交,确定RNA片段的特异性。结果表明,3个克隆为中(M)片段的cDNA,另两个分别为大(L)和小(S)片段cDNA。核苷酸序列分析证明,克隆的DNA中含病毒特异的核苷酸序列。 相似文献
109.
Median lethal doses (LD50s) of nuclear polyhedrosis virus (NPV) were determined in neonatal offspring ofSpodoptera frugiperda (J. E. Smith) (Sf) larvae captured in southeastern Louisiana in 1981, 1982, and 1984. These LD50s ranged from 1.8 to 16.3 polyhedral inclusion bodies (PIB)/insect. The LD50s significantly (P<0.05) increased during the season of 1982 but had no pattern in 1981 or 1984. However, the Sf populations increased in heterogeneity of response to the NPV during all 3 years. The LD50 increased from 4.1 to 18.7 PIB/insect in a Sf laboratory colony exposed to the NPV LD80 for 7 generations, whereas in a control colony not exposed to NPV the LD50 was 5.9 PIB/insect after 7 generations. 相似文献
110.
1. Concentrations of the neurotransmitter amines noradrenaline (NA), dopamine (DA), and 5-hydroxytryptamine (5-HT) and the acid metabolites homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were determined in four regions of postmortem brains of demented patients with or without Alzheimer's disease (AD). 2. NA was deficient in the temporal cortex (BA 21) of AD, but not of non-AD, patients. 3. Caudate, in particular, had an impaired dopaminergic system in AD patients, with low HVA levels. 4. In all regions investigated [amygdala, caudate, putamen, temporal cortex (BA 21)] 5-HT was significantly depleted in AD patients, and 5-HIAA was also depleted in amygdala and caudate. 5. These results indicate that neurotransmitter systems other than cholinergic systems are also widely affected in AD and suggest that these deficits may also play an important role in determining the symptomatology of AD. 相似文献