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51.
Alexander V. Zhdanov Ruslan I. Dmitriev Dmitri B. Papkovsky 《Cellular and molecular life sciences : CMLS》2011,68(5):903-917
Bafilomycin A1 (Baf) induces an elevation of cytosolic Ca2+ and acidification in neuronal cells via inhibition of the V-ATPase. Also, Baf uncouples mitochondria in differentiated PC12
(dPC12), dSH-SY5Y cells and cerebellar granule neurons, and markedly elevates their respiration. This respiratory response in dPC12 is accompanied by morphological changes in the mitochondria and decreases the mitochondrial pH, Ca2+ and ΔΨm. The response to Baf is regulated by cytosolic Ca2+ fluxes from the endoplasmic reticulum. Inhibition of permeability transition pore opening increases the depolarizing effect
of Baf on the ΔΨm. Baf induces stochastic flickering of the ΔΨm with a period of 20 ± 10 s. Under conditions of suppressed
ATP production by glycolysis, oxidative phosphorylation impaired by Baf does not provide cells with sufficient ATP levels.
Cells treated with Baf become more susceptible to excitation with KCl. Such mitochondrial uncoupling may play a role in a
number of (patho)physiological conditions induced by Baf. 相似文献
52.
The c-myc oncogene driven by immunoglobulin enhancers induces lymphoid malignancy in transgenic mice 总被引:39,自引:0,他引:39
J M Adams A W Harris C A Pinkert L M Corcoran W S Alexander S Cory R D Palmiter R L Brinster 《Nature》1985,318(6046):533-538
Transgenic mice bearing the cellular myc oncogene coupled to the immunoglobulin mu or kappa enhancer frequently develop a fatal lymphoma within a few months of birth. Since the tumours represent represent both immature and mature B lymphocytes, constitutive c-myc expression appears to be highly leukaemogenic at several stages of B-cell maturation. These myc mice should aid study of lymphoma development, B-cell ontogeny and immunoglobulin regulation. 相似文献
53.
Identification and mapping to chromosome 1 of a susceptibility locus for periinsulitis in non-obese diabetic mice 总被引:11,自引:0,他引:11
Insulin-dependent diabetes mellitus (IDDM) is a polygenic disease caused by autoimmune destruction of insulin-producing beta cells in the islets of Langerhans. Its onset is preceded by a long and variable period in which lymphoid cells infiltrate the pancreas but first remain outside the islets (peri-insulitis) before invading them (insulitis). Among susceptibility loci, only the major histocompatibility complex (MHC) has been clearly assigned. Genetic study of the nonobese diabetic (NOD) mouse model for insulin-dependent diabetes mellitus has revealed genetic linkage of insulitis and of early onset diabetes with two non-MHC loci mapping to chromosome 3 and 11 respectively. Here we report a close association of periinsulitis with a third non-MHC locus mapping to chromosome 1. Successive stages in the progression of diabetic disease thus appear to be controlled by distinct genes or sets of genes. 相似文献
54.
An erosion of the power of people and their communities to control any more than a fragment of their future continues. Educational and governmental policy decisions are, for the most part, mandated from above and/or outside the community. This paper introduces a model which reflects Freire's humanizing pedagogy. This method is a vehicle, an avenue of empowerment for people and their communities to control their own destiny and the future of their community. The model is Interactive Management (IM) and its derivative, The CogniScope System. IM is a specialized system of management using collaborative teamwork to define and resolve highly complex issues. The process includes the integration of the diversity of perceptions of the participants with regard to the given ssues, builds consensus and joint ownership of the process and/or product, and creates a collaborative action plan to accomplish the participants' goals. The principal intangible outcome of the process, however, is the reflective participation, which leads to action, and the learning that occurs among the community of stakeholders present. The process of Interactive Management (IM), enhanced through the use of the CogniScope System, is described and examples of its application by First Nation peoples are shared. 相似文献
55.
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57.
Virus-induced cell fusion enhanced by phytohaemagglutinin 总被引:3,自引:0,他引:3
58.
P Bardos C Carnaud J F Bach 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,289(16):1251-1254
The serum thymic factor (FTS) and one of its structural analogues have been administered to adult normal Mice for 2 to 12 weeks. This treatment induced a significant increase in spleen cell natural killer (NK) activity, evaluated by a cytotoxicity assay against YAC cells. 相似文献
59.
Yuri D. ZAKHAROV Olga P. SMYSHLYAEVA Yasunari SHIGETA Alexander M. POPOV Tatiana D. ZONOVA 《自然科学进展(英文版)》2006,16(13):50-67
The aim of this paper is to reconstruct the Jurassic-Early Cretaceous climatic conditions using new isotopic data. Paleobotanical data indicate that a cooling occurred gradually just after Late Triassic, and a temperature minimum was reached in the Pliensbachian. This was followed by a climatic optimum in the early Toarcian, cooling in the late Toarcian and a second climatic optimum in the Oxfordian. Published isotopic thermometry data and our new results on isotopic composition of some Jurassic invertebrate shells from the Russian Platform, Poland, Germany and England generally confirm this pattern, and also indicate a third climatic optimum in the Middle Callovian. Middle-Late Mesozoic adult belemnites apparently lived during their spawning phase, in shallow waters similar to extant Nautilus. However, at least juvenile belemnoids, unlike ammonoids, engaged in significant short-term vertical migrations in the water column, reaching colder waters of the upper bathyal zone. 相似文献
60.