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Data on mineral elements in spirulinas being limited, we analyzed macrominerals and trace elements of samples from France and Africa. Spirulinas cultivated in France have a composition in macromineral elements similar to those of the literature. The entire contents of trace elements are low. Unlike marine cyanobacteria, they do not concentrate rare-earth elements. Spirulina harvested in Chad has high levels in macrominerals and trace elements, due to traditional drying and harvesting methods. Rare-earth element levels are attributed to this pollution and not to their concentration in spirulinas, because rare-earth element normalized profiles of spirulina are strictly parallel to those of ouadis mud and very different from those of ouadis water. Despite the sometimes high content of total As, normal water consumption in Chad presents no health problems. Spirulinas grown in Togo, Niger, Mali, Burkina-Faso and Central African Republic have chemical compositions similar to those of Chad spirulinas, but with a lower content of macromineral and trace elements, reflecting a lower mineral pollution. Rare-earth element normalized patterns dismiss an aeolian pollution and the pollution is rather of pedological origin. They show no toxicity problem except spirulinas from Burkina-Faso, whose Pb content is too high. The variability of composition of spirulinas can be largely attributed to the mineral pollution of the samples. Significant levels of rare-earth elements sometimes found in the literature reflect this pollution.  相似文献   

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Sans résuméAvec la collaboration technique de Mme Cotte (C. N. R. S.).  相似文献   

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《Médecine Nucléaire》2014,38(5):299-302
Breast cancer treatment has developed rapidly for the last 15 years, promoted by a better understanding of tumour growth biology. Targeted therapies have been rapidly expending: immunotherapy, targeted chemotherapy, endocrine therapy efficacy enhanced by mTOR inhibitors. Changes of molecular profiling tumours during the illness need to perform regularly biopsies and to adapt drugs. This article will focus on a high-level overview of main advances across systemic treatment.  相似文献   

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《L'Anthropologie》2018,122(1):14-32
The site of Baigu, in Bose basin, autonomous region of Guangxi Zhuang (China), dated to just over 800,000 years, delivered a rich lithic industry, mainly composed of pebbles tools. This industry consisted by the abundance of heavy and huge pebbles tools, the choppers, the picks massive and the hand-axes. The flakes have been rare retouched.  相似文献   

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Recent researches conducted in Morocco in the frame of the “Programme Casablanca” provide a firm ground to set up a biochronology of the Pliocene and Pleistocene based upon the succession of Mammalian faunas, thanks to the occurrence of well-dated landmarks, and despite very scarce absolute datations. The site of Lissasfa, dated to the Miocene-Pliocene boundary by rodents, testifies to important exchanges with Europe. That of Ahl al Oughlam yielded more than 100 vertebrate species. The evolutionary stages of its rodents, carnivores, bovids, Kolpochoerus, as well as the absence of Equus, allow us to refer it to the late Pliocene, at ca. 2.5 Ma. The Thomas and Oulad Hamida quarries in Casablanca cut through a unique succession of marine and continental levels going back to the lower Pleistocene, yielding the earliest evidence of human presence in Morocco. Later stages of this human occupation are documented by the Middle Pleistocene levels of these quarries, and by several other sites, most of which are also located in the Rabat-Casablanca region, thus confirming the importance of this coastal area in human history. However, the first chapter of this history in North-western Africa, at present illustrated by the sites of Aïn Hanech and Mansourah in Algeria, remains poorly documented in Morocco.  相似文献   

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