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Summary After injection of a high dose of 5-hydroxytryptamine into rats, the blood reveals a strong increase of the blood platelets and a definite decrease of the eosinophiles. The maxima of increase and decrease are in temporal accordance. 相似文献
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Hans Nachtsheim 《Cellular and molecular life sciences : CMLS》1954,10(8):317-326
Summary The mutation of homologous genes can produce the same changes in phenotype in different mammals, animals as well as human beings. In this way the same hereditary disease can arise in man and animal. This fact permits the study of human hereditary diseases in model experiments in animals under conditions impossible to be realized in man. How far the parallelism between human beings and animals can be taken and where the limits of this parallelism are, which are the problems of the comparative heredo-pathology in detail, and how these problems may be attacked, is demonstrated here in numerous examples.
Nach einem Vortrag in der Nederlandse Anthropogenetische Vereniging in Utrecht am 28. November 1953. 相似文献
Nach einem Vortrag in der Nederlandse Anthropogenetische Vereniging in Utrecht am 28. November 1953. 相似文献
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When Research and Practice Collide: The Role of Action Research When There Is a Conflict of Interest with Stakeholders 总被引:1,自引:0,他引:1
This article discusses problematic aspects of the role of the action researcher when working with multiple stakeholders on a complex research project concerning regional development. The case presented here deals with the improvement of the regional innovation system in a small region in the south of Norway. The project resulted in a conflict between stakeholders and the action research (AR) team. We claim that when working in a regional context, the role of the action researcher is set to be a collaborator in a context of power play; the ultimate stakeholders must be defined as the citizens in that region. Therefore, in some situations the action researcher must have a legitimatised right to abandon collaboration and present a critical voice in the public deliberation. Strategic power play and strategic action by stakeholders represent a clear threat to the soft approach of collaboration, reflectivity, and democratic dialogue that AR represents. The ultimate challenge and obligation of the action researcher is to improve democracy in society in a long-term perspective through representing a critical capacity in the public deliberation. 相似文献
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It has recently been shown that RNA interference can be induced in cultured mammalian cells by delivery of short interfering RNAs (siRNAs). Here we describe a method for efficient in vivo delivery of siRNAs to organs of postnatal mice and demonstrate effective and specific inhibition of transgene expression in a variety of organs. 相似文献
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de Lonlay P Valnot I Barrientos A Gorbatyuk M Tzagoloff A Taanman JW Benayoun E Chrétien D Kadhom N Lombès A de Baulny HO Niaudet P Munnich A Rustin P Rötig A 《Nature genetics》2001,29(1):57-60
Complex III (CIII; ubiquinol cytochrome c reductase of the mitochondrial respiratory chain) catalyzes electron transfer from succinate and nicotinamide adenine dinucleotide-linked dehydrogenases to cytochrome c. CIII is made up of 11 subunits, of which all but one (cytochrome b) are encoded by nuclear DNA. CIII deficiencies are rare and manifest heterogeneous clinical presentations. Although pathogenic mutations in the gene encoding mitochondrial cytochrome b have been described, mutations in the nuclear-DNA-encoded subunits have not been reported. Involvement of various genes has been indicated in assembly of yeast CIII (refs. 8-11). So far only one such gene, BCS1L, has been identified in human. BCS1L represents, therefore, an obvious candidate gene in CIII deficiency. Here, we report BCS1L mutations in six patients, from four unrelated families and presenting neonatal proximal tubulopathy, hepatic involvement and encephalopathy. Complementation study in yeast confirmed the deleterious effect of these mutations. Mutation of BCS1L would seem to be a frequent cause of CIII deficiency, as one-third of our patients have BCS1L mutations. 相似文献
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在过去的20年,科研工作者已经在分子肿瘤领域取得了划时代的重大发现,这很大程度上归功于免疫组织化学方法的应用。这一方法在脑肿瘤研究中也已经从试验阶段走向了成熟。 相似文献