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101.
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
102.
Shin-Ichi Hayama Rika Akamatsu Mayumi Kishimoto Masatsugu Suzuki Hideo Nigi 《Primates; journal of primatology》1988,29(3):423-426
Diverticular disease of the colon was detected in a female Japanese monkey by X-ray examination. The monkey was 15 years old
and had been kept under captive conditions for nine years. Lack of appetite and activity, and constipation were observed.
The monkey was given fiber-rich vegetables and wild plants, and its appetite and activity then improved. Based on a consideration
of various factors, it is suggested that one possible cause of the diverticulosis in this case was a low dietary fiber intake. 相似文献
103.
M. Yano K. Okuno H. Satoh T. Omura 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1988,76(2):183-189
Summary Eight dull mutants that lower the amylose content of rice endosperm as well as waxy mutant and a cultivar with common grains were crossed in a diallele manner. The amylose content of F1 and F2 seeds was determined on the basis of single grain analysis. It was concluded that the low amylose content of dull mutants is under monogenic recessive control. Alleles for low amylose content are located at five loci designated as du-1, du-2, du-3, du-4 and du-5. These loci are independent of wx locus located on chromosome 6. The five du loci have an additive effect in lowering the amylose content. Two loci, du-1 and du-4, were found to be located on chromosomes 7 and 4, respectively. 相似文献
104.
105.
The purpose of this study was to reproduce and extend an earlier investigation of the effects of human exposure to combined, 60-Hz electric and magnetic fields. This paper presents the neurobehavioral results. Thirty men participated in one training session and four testing sessions. Subjects were randomly assigned to two groups. The 18 subjects in Group I were exposed (9 kV/m, 20 microT) and sham exposed in two counterbalanced orders. In Group II, half of 12 subjects were exposed (9 kV/m, 20 microT) every session, and the remaining half were sham exposed every session. The study was doubly blinded. Measures of cardiac interbeat interval, event-related brain potentials, and performance were obtained before, during, and after exposures. As in the earlier study, exposure to the combined field resulted in a statistically significant slowing of heart rate, in changes in late components of event-related brain potentials, and in decreased errors on a choice reaction-time task. In addition, field effects on several other measures approached statistical significance. The physiological measures obtained during exposure indicated that effects were greatest soon after the field was switched on, and again when it was switched off. The data indicate that changes in exposure level may be more important than duration of exposure for producing effects in human beings. 相似文献
106.
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
107.
Serum antioxidant enzyme activity in Parkinson's disease 总被引:2,自引:0,他引:2
Jawahar Kalra Ali H. Rajput Subrahmanyam V. Mantha Kailash Prasad 《Molecular and cellular biochemistry》1992,110(2):165-168
Summary The activities of superoxide dismutase (SOD; EC 1.15.1.1) and glutathione peroxidase (GSHPx; EC 1.11.1.9.), the enzymes that metabolize the superoxide anion and hydrogen peroxide, respectively, were measured in serum
from healthy subjects and patients with Parkinson's disease (PD). The activities of SOD and GSHPx in patients with PD were higher than those in normal healthy individuals. These results suggest that the increased activities
of these enzymes could be due to oxidative stress in the initial stages of this disease. 相似文献
108.
Yoshiaki Sumiyoshi Masahiko Kikuchi Morishige Takeshita Kohiti Ohshima Yuhiti Masuda 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,61(1):201-207
In Japan, histiocytic necrotizing lymphadenitis (Kikuchi’s disease) is a relatively common reactive lesion affecting lymph
nodes, but the histogenesis and pathogenesis of the disease have not been clarified. Alpha-interferon has a role in the body’s
defense against, viral infections. Using a polyclonal antibody to human alpha-interferon, we found numerous cells, mainly
histiocytes, containing alpha-interferon in affected foci in the lymph nodes from 24 patients with Kikuchi’s disease. Tubuloreticular
structures, thought by some authors to be associated with the production of interferon, were detected by electron microscopy
in histiocytes, activated lymphocytes and vascular endothelial cells in the affected foci. These results suggested that the
formation of tubuloreticular structures is a secondary phenomenon following stimulation by alpha-interferon. Further, the
activity of 2′–5′ oligoadenylate synthetase, which is induced by alpha-interferon and enhanced during the early or active
stage of viral infection, showed increased levels of activity in the active stage of Kikuchi’s disease and decreased to normal
levels in the convalescent stage 2 weeks later. These results suggested the possibility of a viral etiology for Kikuchi’s
disease. 相似文献
109.
Summary In order to evaluate the frequency of skin sensitivity to Storage Mites and the role of such sensitization in respiratory allergic disease in workers with occupational exposure to stored items we studied 217 dock workers, 93 farmers and 104 white collars.From the results of skin prick tests the sensitization to sole Storage Mites appears significantly higher among people working in docks or farms, compared with a control group. This confirms the role of the working environment in inducing sensitization to Storage Mites. Rhinitis and asthma however affect nearly always (27/29 cases) people with an associated sensitization to House Dust Mites. Further studies are needed to define the allergenic importance of Storage Mites in working environments. 相似文献
110.
电镜观察发现,大豆种子在刚开始萌发时胚根细胞中未能见到线粒体,线粒体是在种子萌发过程中逐渐出现的,由原质体再分化发育而成。对照胚根细胞内原质体在低温吸张过程中明显膨胀,在回温后胚根细胞中原质体仍不能发育成线粒体,甚至网状膜结构破坏,呈空泡化;经聚乙烯醇(PVA)和聚乙二醇(PEG 6000)预处理的大豆种子在同样条件下线粒体能继续发育,在回温后预处理胚根细胞中线粒体发育良好,具有明显的双层膜和管状嵴的结构。这些结果表明,在低温吸胀过程中原质体能够继续再分化发育成线粒体是提高大豆种子活力和抗冷力的重要原因。 相似文献