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Glucocorticoid (GC) hormones have been introduced as therapeutic agents in blood cancers six decades ago. The effectiveness of GC treatment stems from its ability to induce apoptotic death of hemopoietic cells. A major impediment in GC therapy is the acquisition of resistance to the drug upon repeated treatment. In addition, some blood cancers are a priori resistant to GC therapy. Usually, resistance to GC correlates with poor prognosis. Albeit the wide use of GC in clinical practice, their mode of action is not fully understood. The cellular response to GC is initiated by its binding to the cytosolic GC receptor (GR) that translocates to the nucleus and modulates gene expression. However, nuclear activities of GR occur in both apoptosis-sensitive and apoptosis-resistant cells. These apparent controversies can be resolved by deciphering non-genomic effects of GCs and the mode by which they modulate the apoptotic response. We suggest that non-genomic consequences of GC stimulation determine the cell fate toward survival or death. Understanding the cellular mechanisms of GC apoptotic sensitivity contributes to the development of new modalities for overcoming GC resistance.  相似文献   
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A column that specifically binds gibberellins was prepared bycovalent binding of anti-GA antibodies to Sepharose. By usingsuch an immunoadsorbent column, radio-immunoassay for quantitativedetermination of gibberellins was developed. Using this method,diffusible GA from apices of etiolated pea seedlings was isolatedin one step and determined quantitatively. (Received March 29, 1974; )  相似文献   
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Understanding species movement in the agroecological system is an important theme in ecology. A mark–release–capture experiment was conducted to study the dispersion behaviour of the Mediterranean fruit fly, Ceratitis capitata (Wied.; Diptera: Tephritidae; Medfly) in northern Israel. Four pairs of pear and citrus orchards were selected for the field experiments. Sterile flies dyed with different colours were released in three seasons during 2015 and 2016, based on the phenological stages of the hosts. The total number of captured marked sterile flies per trap (FT) was approx 300 in both April and August. In November, FT values decreased by about 35% to approximately 200. The wild Medfly that were also captured showed an opposite trend, from an FT of 1.8 and 6.4 in April and August, respectively, to an FT of about 330 in November. Marked sterile flies were captured in both the release and the neighbouring orchard sites. We found that the Medfly migrates from pear to citrus orchards during spring and from citrus to pear during summer, when there are no fruit-bearing trees in the orchards. However, during November, when the wild Medfly population prevails in the area, a clear pattern of migration is hard to identify, perhaps because of a possible interaction with the wild fly's population.  相似文献   
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An ecoinformatics approach was used to test how two noxious species in grapevines with varying host preferences and movement characteristics: the European grapevine moth (Lobesia botrana), and a parasitic fungus, the grape powdery mildew (Uncinula necator), are affected by local and landscape variables. Data were collected from 202 vineyards during four seasons: 2013, 2014, 2016 and 2017 and analysed using generalized mixed models. We hypothesized that the European grapevine moth would be affected most by the landscape variables, while the grape powdery mildew would be affected most by local ones. We found that the number of sprayings during the season was an important variable explaining variation in infestation levels between vineyards for both species. At the landscape scale, we found larger variations in the relationship between the studied variables and the two pests, but both were also affected by the surrounding land use including areas of deciduous orchards. Understanding the factors that affect the occurrence of various pests in the same environment might improve farmers' decision-making.  相似文献   
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