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Physiological functions of mineral macronutrients 总被引:6,自引:0,他引:6
Frans JM Maathuis 《Current opinion in plant biology》2009,12(3):250-258
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Nanne Bloksma C. Frieke Kuper Frans M. A. Hofhuis Barry Benaissa-Trouw Jan M. N. Willers 《Cancer immunology, immunotherapy : CII》1999,16(1):35-39
Summary Concanavalin A, endotoxin, poly I : C, and tumour necrosis serum (TNS) were compared for antitumour activity against Meth A sarcoma transplanted in syngeneic BALB/c mice and their capacity to induce tumour necrosis factor (TNF), heat-stable cytostatic factors, and heat-labile interferon in the blood of normal and Corynebacterium parvum-pretreated mice. All the agents induced hyperemia and inhibition of mitosis at 4 h, and by 24 h many tumours had a dark necrotic centre. Subsequent tumour growth was inhibited and in some of the treated mice tumours regressed completely. Poly A : U and normal mouse serum did not induce regression and their effects were less marked in all other respects, suggesting that these events may be linked. The necrotizing effects of concanavalin A and poly I : C are unlikely to be mediated by TNF, because neither agent could mimic endotoxin in eliciting RNase-resistant necrotizing and regressing activity in the serum of mice pretreated with C. parvum. Poly I : C did not induce strong cytostatic activity in the sera of C. parvum-treated mice, and for this and other reasons these factors are unlikely to be responsible for the observed effects. Concanavalin A, endotoxin, and poly I : C induced high levels of serum interferon but purified interferon had only weak antitumour activity in the Meth A system, suggesting that interferon may not be the mediator.From these and other data it is concluded that there is no clear relationship between the capacity of the agents to induce tumour necrosis and their capacity to elicit TNF, cytostatic factors, and interferon. 相似文献
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Ernst J. M. Speel Frans C. S. Ramaekers Anton H. N. Hopman 《The Histochemical journal》1995,27(11):833-858
Summary An overview is given of the different non-radioactive cytochemical detection methodologies that are currently utilized to localize nucleic acid sequences in chromosomes, cells and tissue sections. Dependent on the reporter molecule (fluorochrome, enzyme or hapten) that is used to modify the appropriate nucleic acid probe, and the sensitivity that is required, the in situ hybridized sequences can be detected either directly after hybridization or indirectly, using cytochemical detection and amplification layers. These may then contain antibody and/or avidin molecules conjugated to fluorochromes, enzymes or colloidial gold particles. Since the choice of a suitable probe-labelling method in combination with a fluorescence, enzyme cytochemical or immunogold-silver detection procedure is often determined by the user's own practical experience and applications, the different detection methodologies are compared with each other in detail with respect to sensitivity, resolution, applicability for multiple probe detection, and signal evaluation. Furthermore, procedures are reviewed for the combination of in situ hybridization with immunocytochemical detection of proteins and/or incorporated bromodeoxyuridine, which allow the simultaneous visualization of genomic phenotypic and/or cell cycle parameters in the same sample. Possible improvements with respect to sensitivity, specificity and multiplicity of the detection methods, which may be interesting for one's own experimental design, are finally being discussed. 相似文献
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Frans B. M. de Waal 《Primates; journal of primatology》1990,31(4):597-600
Rhesus mothers (Macaca mulatta) may hold their own infant together with the infant of another female in a so-called double-hold. This behavior was observed
240 times in 23 individual females in two independent captive groups. Approximately nine out of ten times, the second infant
was from a dominant matriline. It is suggested that females try to promote future association between their own offspring
and high-ranking youngsters. 相似文献