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1.
In oncology, positron emission computed tomography (PET/CT) has become an essential tool for initial staging, response evaluation and follow-up of cancer patients. Most of the frequent tumors (lung, breast, esophagus, and lymphomas) are highly avid for 18F-fluorodeoxyglucose (18FDG), but prostate cancer has not demonstrated significant uptake of FDG. The development of new tracers labeled with 18F such as choline analogs allowed already to obtain interesting results particularly in patients with biological relapse and inconclusive conventional imaging work-up. The impact of 18F-flurocholine PET/CT on patient management needs to be validated in large studies, but many centers use already this examination in order to guide further management, including radiotherapy planning.  相似文献   

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The site of Longgupo, discovered in 1984, is located south of the crossing of the Three Gorges of the Yangtze, in the eastern part of Chongqing Province. Situated on the limestone slope of the Miaoyu Valley, three excavation campaigns have been carried out since 1985. The first two seasons took place from 1985–1988 and 1997–1998, directed by W.B. Huang and the last campaign from 2003–2006 by E. Boëda and Y.M. Hou. After the first two campaigns, the presence of several bones, with an estimated age of 1.9 My, notably including a mandible fragment attributed to a hominid2 and the discovery of more than 20 lithic artifacts incited not only great interest in the scientific community, but controversy as well since these data contradicted diffusion models of the first hominids out of Africa. Paleoanthropological data often being privileged over other data, including lithic artifacts, the anthropic nature of the site was contested. Yet the few artifacts from the initial excavations irrefutably demonstrate their manufacture by humans, in particular those in exogenous stone. To definitively re-establish the authenticity of this site by applying the latest investigative methods, a new Franco-Chinese campaign was organized. The objective of the 2003–2006 field seasons focused on understanding and analysis of the archaeological data in their geomorphological and stratigraphic contexts.  相似文献   

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The collect of the fossiliferous nodules starts in 1979 in the Saint-Louis opencast mine at Montceau-les-Mines, France. A team of amateur paleontologists excavates more than 100,000 nodules containing very well-preserved fauna and flora from the Late Carboniferous (Stephanian).  相似文献   

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Culture conditions, allowing the unlimited growth and maintenance in shaken suspensions of a kinetin dependent strain of tobacco pith cells, were determined. Cell clusters from 1 to 25 cells were selected from the cultures to study the cell multiplication after addition of specific growth factors to the basal medium. Cell division was found to be strictly dependent upon the presence in the medium of both kinetin and auxin. In complete medium the generation period was 45 to 49 hours. Kinetics of the total protein synthesis in the cell suspensions have been measured either by estimation of protein nitrogen or by 35S incorporation into the proteins. After 3 days of culture, growth was exponential, as expressed by cell number or protein synthesis, which varied proportionally. Evidence was also found that the initial incorporation rate of radioactivity into the proteins was more rapid than expected from the increment of the protein net weight. It seems therefore reasonable to assume that a significant amount of protein turn over does exist during the initial period of growth. This phenomenon was observed even when no cell division occurred. Kinetin significantly activated protein synthesis, whether or not auxin was present in the medium.  相似文献   

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A 122 cm-long core was taken in the El-Guettiate Sebkha of Skhira (southeastern part of Tunisia) in order to investigate the recent palaeoenvironmental evolution of this region. The quantitative and qualitative analysis of ostracod and benthic foraminifera assemblages coupled with a correspondence analysis allows the reconstruction of palaeoenvironmental changes during the Holocene in this area. Four typical associations of ostracods (open marine, coastal marine, lagoonal and estuarine brackish) and two associations of benthic foraminifera (coastal and lagoonal) were distinguished. The onset of restricted lagoonal environments linked to the building-up of sand spit led to the onset of restricted lagoon and brackish environment at cal. 5408 years BP. The Shannon and equitability index of diversity were used to decipher the structural variations of the populations of ostracods and benthic foraminifera along the sampled core. We note a reduction in the Shannon index from the bottom to the top, which indicates a progressive isolation of the biotope. The open lagoonal episode is characterized by high values of diversity. During restricted lagoonal episodes the Shannon and equitability index are reduced. The correspondence analysis reveals an environmental gradient related to the marine influence. It shows an antagonism between the widely opened estuarian lagoonal species and those of restricted lagoon. The less opened estuarian lagoonal taxa occupy an intermediate position. Based on these evidences, microfauna carried out in the El-Guettiate Sebkha allows us to recognize four phases beginning with a widely opened estuarian lagoon (ca. cal. 7460 years PB), followed by a restricted lagoon (ca. cal. 5408 years BP) and finally a brackish lagoon evolving towards the present-day sebkha environment. The opened estuarine lagoon is characterized by high values of species richness and diversity indices.  相似文献   

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Effect of leaf position on the susceptibility of melon plants to artificial infection with powdery mildew, Sphaerotheca fuliginea The leaf position of melon plants seems to play a role on their susceptibility when they are artificially infected with powdery mildew Sphaerotheca fuliginea. The cotyledons are generally very susceptible, while the first leaf relatively resistant; the susceptibility again continues up to the 4th–5th leaf (but less susceptible than the cotyledons) and then after it decreases; these results can be obtained on plants in greenhouse or on detached leaves in Petri dishes. From this observation, we think that the screening of melon genotypes for resistance to powdery mildew can be evaluated neither on the cotyledons which are very susceptible nor on the first leaf which is resistant, but on the third leaf which is moderately susceptible. In fact, there is a good correlation between the reaction of the third leaf and the resistance or susceptibility of genotypes.  相似文献   

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Most of patient suffering from a prostate cancer will develop a castration resistance. In this common and clinically challenging situation, chemotherapy was not considered very useful until mid 2000s. Docetaxel is now recognized as a standard of care, improving overall survival and quality of life. However, new drugs are needed. Two compounds (cabazitaxel and abiraterone) are now underway to official registration and an autologous vaccin strategy (Sipuleucel) demonstrated a benefit in survival. Based on a greater knowledge of biology, many other agents are currently under development, such as new specific peripheral anti-androgens, anti-angiogenic therapies, or proteasome inhibitors. All these new drugs are promising and may provide more efficient therapies against this incurable disease in the near future.  相似文献   

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This paper, analyses the graphic evidences of the boundaries of Tagus between Spain and Portugal from the perspective of the model defended by our team. This model proposes the existence of the relationship between graphic markers: paintings, engravings in the open air, decorations over dolmens and menhirs, understood as a compact ideological group fixed in the organization social system of European producing people and metallurgical that occupying this landscape. This argument attempt to verify the possibilities of applying a pre-defined model in an area in which have been developed investigation models, focused to study megalithic monuments, menhirs, habitational areas, paints and engravings that shows symbolic expressions of the tradition to justify the property of rich areas in natural resources in what metallurgical have a remarkable importance.  相似文献   

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The Baume of Montclus is located in the Cèze valley (Gard). This site gave its name to a prehistoric tool-age, the Montclusian, which parted from the Sauveterrian. Middle and Upper Montclusian are present in Montclus, unlike the Lower Montclusian. The Montclusian industry, which starts here in about 8000 BP, includes a very high proportion of hypermicrolithes. It is followed by a Castelnovian industry from around 7000 BP. This one features very different Montclusian, showing thus a break. The Castelnovian survives in Montclus while the Cardial is already settled in Châteauneuf-les-Martigues and sites around the Ardèche river. After these Montclusian levels appear Cardial and Chassean layers. Neolithisation has been very gradual here, affecting tools first before the arrival of ceramic, around 6500 BP. What is the origin of Montclusian? And what could have become? Its origin might be further west with the Causses and Languedoc, where levels are rather similar. The Sauveterrian origin has long been established. But research shows a great diversity among the Sauveterrian originated industries. What the Montclusian was going to become is to discovered from the Lower Montclusian, quite original, and which should be found in other site. Montclusian might be on the geographic and cultural boderline of 2 districts: one being located west of the Rhône river, influenced by Sauveterrian, and which gave birth to Montclusian, the other east of the Rhône river bears witness to Castelnovian.  相似文献   

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We report through this work the experience of nuclear medicine department at Ibn-Sina hospital (Rabat), in the treatment of hyperthyroidism with iodine-131. We retrospectively studied a cohort of 280 patients with hyperthyroidism, from several regions of Morocco between January 2001 and January 2010. A clinical examination and a serum assessment of TSHus, FT4 and FT3 have been made at baseline and at 3, 6, 12 and 24 months after radioiodine therapy. The activity of iodine-131 administered ranged from 296 to 740 MBq and depended on the pathology being treated, age, thyroid volume, intensity of clinical and biological hyperthyroidism and socioeconomic situation. Radioiodine therapy has often been proposed as a treatment for second or third intention, 71 patients were initially treated with iodine-131, while 209 patients had received iodine-131 after failure of medical treatment and/or recurrence after surgical treatment. Graves’ disease was the most common etiology (60%), followed by toxic adenoma (20%), and multinodular toxic goiter (13%). The therapeutic efficacy of a single dose of radioiodine evaluated after a 6-months follow-up was 92% in Graves’ disease, 98% in toxic adenomas and 97% in toxic multinodular goiter. No acute complication was observed. Taking into account our socioeconomic context, radioiodine therapy remains the preferred treatment of hyperthyroidism in our country with good value vs. price and excellent tolerance.  相似文献   

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L'espèce Amelanchier ovalis Medikus (Syn. Mespilus amelanchier L.), largement distribuée en Europe, comprend une race diplode (2 n = 34) et une race tétraplode (2 n = 68). Celles-ci diffèrent l'une de l'autre par des caractères quantitatifs (taille des feuilles, longuer des pédicelles, des pétales et des graines). Le nom A. ovalis est typifié ici-même par un specimen (L.H. 646.11) de l'Herbier de Linné qui représents le cytotype diplode. Le cytotype tétraplode est nommé ici: A. ovalis subsp. embergeri Favarger et Stearn. Les caractères cytologiques, la distribution et la nomenclature des deux sous-espèces sont discutés.  相似文献   

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Due to unparalleled conditions of preservation below volcanic ashes of the late glacial Laacher-See volcano, the Central Rhineland region, located at the geographic hinge between the North German Lowlands and the Highland zone, permits detailed insights into the environmental and vegetational history of the Allerød-Interstadial and has produced fundamental data for the reconstruction of the way of life of hunter-gatherer groups of that time. The recently investigated site of Bad Breisig, dating to the final part of the Allerød, is the first record of a Late Glacial human settlement of the Central Rhineland after the disastrous environmental destruction caused by the eruption of the Laacher-See volcano. The site is an important chronostratigraphic and typological key in the understanding of the development of the Final Palaeolithic technocomplex with backed points in Central Europe.  相似文献   

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