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Disease control by inducers of resistance Induces of resistance open a new way in the search for control. It may be assumed that inducers of resistance will be used more and more in the coming years.  相似文献   

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Although the efficacy of radionuclide therapy has been demonstrated in several indications, the development of this new therapeutic modality is limited. However, promising results have been obtained, especially using different radiolabeled somatotatin analogs for neuroendocrine tumors or radioimmunotherapy for lymphoma. Toxicity is limited, particularly if patients are selected based on their background. The use of new vectors (bombesin, anti-PMSA monoclonal antibody), pretargeting system and innovative radionuclides (Copper-67, Astatine-211) suggests interesting perspectives, particularly to target small tumor masses or residual disease.  相似文献   

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Normal prostate cells and prostate cancer cells produce prostate-specific antigen (PSA): thus, it is frequently increased in non-malignant conditions such as prostatitis and benign prostatic hyperplasia. Indeed, PSA is an excellent biomarker to monitor disease progression. The low diagnostic specificity of PSA leads to many false-positive and a large number of biopsies. These well-recognized limitations of PSA suggest that new prostate cancer biomarkers could play a useful role in reducing the number of unnecessary biopsies.  相似文献   

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Some traditional concepts on lingulid paleoecology are reviewed and discussed in regard to new data on the ecology of Recent lingulid brachiopods. Fossilization in life-position occurs under several ecological conditions, e.g. dessication or emersion of the substratum, prolonged increase in salinity, perhaps very rapid sedimentation, extreme changes in temperature, and fossilization of flat-lying shells occurs under prolonged reduction in salinity, storms, natural death. Catastrophic environmental changes cause the fossilization of lingulids. Such events may affect one or more ecological features which may have a direct or indirect effect on the lingulid biology. At this time, the biotype does not correspond to the habitual one, and the survival and behavior of the lingulids depend on the severity of the environmental changes and on the tolerance of the animals to the latter.  相似文献   

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Some animal and mineral resources, rarely identified in the levels of the Cantabrian Magdalenian, were exploited by the Paleolithic populations of the Nalón Valley (western Asturias) at the end of the Pleistocene. In this research, we present some of them, preserved in the Las Caldas Cave: dental remains and representations of marine mammals, marine crustaceans and molluscs, and diverse remains of amber and jet. These were selected, collected in ecosystems far away from the cave and, finally, transformed by the groups. These remains seem to complement the common resources exploited in Magdalenian paleoeconomy (e.g., ungulates, birds, fish, small carnivores, vegetables, flint, quartzite, quartz) recovered and exploited biotopes closest to the site. Our aim is thus to confirm a certain mobility of these communities towards the specific sources of raw material in search of subsistence resources potentially used in the activities of these communities (e.g., food, technology, social and symbolic expression, exchange).  相似文献   

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The open air site of Jas-d’en-Biel-1 (Tautavel, Pyrénées-Orientales) is the first trace of Gravettian presence in the extreme east zone of the Northern-Pyrenees Piedmont. The lithic series made up of surface finds indicates that this occupation could belong to a rather recent phase of southern-French Gravettian.  相似文献   

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SUMMARY. Various species of ciliates are characterized by the formation and accumulation in the cytoplasm of mineral concretions which are refringent, isotropic or anisotropic. These cytoplasmic inclusions most often are composed of calcium carbonate; in several species, however, their nature remains partially or even totally undetermined. The isotropic calcium-containing concretions often exhibit a definite shape; the calcium carbonate in this case appears to be bound to an organic substrate. The physiological role of the calcic concretions is not known; their characteristic presence in a given species is not necessarily related to ecological conditions. In a few species the calcification is localized in definite structures: spicules, skeletal plates, or otoliths of organelles supposedly sensory in nature.  相似文献   

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