998 resultados para oncogene k ras
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This research aims to provide a contribution towards understanding how and why certain people can display disobedience behaviors, to overcome unjust situations, and withstand persecutions deployed by authority. The paper presents a hermeneutic content analysis of the autobiographical speeches and texts of Gandhi, M. L. King and Mandela. Our results show that parents' value orientation, experience of injustice during childhood and exploration of alternative viewpoints during adolescence play a crucial role in structuring prosocial disobedience. Findings show also that social responsibility and ingroup communication are important conditions for facing persecutions without dropping original goals.
Osanotto mestaruuskilpailuihin (urheiluseurojen toimenpiteet tarpeen osanoton kohottamiseksi / U.K.)
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The effects of ants on the insect community on inflorescences of Byrsonima crassifolia (Malpighiaceae) were tested in an ant exclusion experiment in a cerrado vegetation in southeastern Brazil. Forty-four species of insects (23 families) and nine species of ants (6 genera and 3 subfamilies) were found on the inflorescences of B. crassifolia. The exclusion of ants, primarily Camponotus sericeiventris and Camponotus spp., reduced the treehopper population to 20% of the original abundance. Ant exclusion and time influenced the abundance of chewing (Exclusion, P<0.001; Time, P<0.002), and sucking insects (Exclusion, P<0.02; Time, P<0.01). Twice as many chewing and sucking insects were found on ant-excluded inflorescences as compared to control inflorescences (P<0.001). One and half more sucking insects were found on ant-excluded than on control inflorescences. Only time significantly influenced the richness of chewing and sucking insects associated with B. crassifolia inflorescences. Inflorescences on control branches were significantly less attacked by herbivores than inflorescences on ant-excluded branches (P<0.001). Therefore, these results suggest that the presence of ants alters the structure of insect herbivore community associated with B. crassifolia.
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Kirje 30.12.1974
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Puhe
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BACKGROUND: Recent evidence indicates that zoledronate, a nitrogen-containing bisphosphonate used to treat conditions of increased bone resorption, may have anti-angiogenic activity. The endothelial cells signaling events modulated by zoledronate remain largely elusive. OBJECTIVES: The aim of this work was to identify signaling events suppressed by zoledronate in endothelial cells and responsible for some of its biological effects. METHODS: Human umbilical vein endothelial cells (HUVEC) were exposed to zoledronate, isoprenoid analogs (i.e. farnesol and geranylgeraniol) and various inhibitors of signaling, and the effect on adhesion, survival, migration, actin cytoskeleton and signaling events characterized. RESULTS: Zoledronate reduced Ras prenylation, Ras and RhoA translocation to the membrane, and sustained ERK1/2 phosphorylation and tumor necrosis factor (TNF) induced JNK phosphorylation. Isoprenoid analogs attenuated zoledronate effects on HUVEC adhesion, actin stress fibers and focal adhesions, migration and survival. Isoprenoid analogs also restored Ras prenylation, RhoA translocation to the membrane, sustained FAK and ERK1/2 phosphorylation and prevented suppression of protein kinase B (PKB) and JNK phosphorylation in HUVEC exposed to TNF in the presence of zoledronate. Pharmacological inhibition of Rock, a RhoA target mediating actin fiber formation, phosphatidylinositol 3-kinase, an activator of PKB, MEK1/2, an activator of ERK1/2, and JNK, recapitulated individual zoledronate effects, consistent with the involvement of these molecules and pathways and their inhibition in the zoledronate effects. CONCLUSIONS: This work has demonstrated that zoledronate inhibits HUVEC adhesion, survival, migration and actin stress fiber formation by interfering with protein prenylation and has identified ERK1/2, JNK, Rock, FAK and PKB as kinases affected by zoledronate in a prenylation-dependent manner.