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Stratigraphic, sedimentological and paleomagnetic studies were conducted on the travertine from Denizli Basin, near Kocabas village, in the Denizli region in Turkey, following the paleontological discovery in 2002. The stratigraphic and sedimentological studies show at least two main cycles of mass travertine, separated by a fluvial deposit and overlain by a fluvio-lacustrine deposit. These travertines must have formed in environments with strong hydrodynamics (streams or waterfalls) and are preferentially located at breaks of slopes. The paleomagnetic study shows that all the quarry travertine presents reverse magnetic polarity. On the other hand, the detrital fluvio-lacustrine deposit above the travertine presents normal geomagnetic polarity, except at the top, where it is reversed. Given the presence of an archaic Homo erectus skull and Villafranchian paleontological remains in the upper travertine unit, the whole travertine dates from the upper Matuyama, and is more recent than the Olduvai event (1.78 Ma). The normal polarity recorded in the upper fluvio-lacustrine deposit could correspond to the Cobb Mountain excursion, dated to 1.22 Ma.  相似文献   

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《Comptes Rendus Palevol》2002,1(3):181-189
The exceptional prehistoric site of Dmanisi, in the South of Georgia, has yielded several hominid fossil remains, including three skulls and three mandibles assigned to Homo ergaster, in volcanic ashes and fluvio-lacustrine sands lying directly on a basalt flow. These levels also contain an archaic lithic industry consisting of pebble tools, cores and flakes, and large mammal remains attributed to the beginning of the Lower Pleistocene (Biharian). The basalt flow has been previously dated to about 1.85 Ma, but the overlying volcanic ash level had not yet been dated. In this paper, we present 40Ar/39Ar dating of plagioclase and glass from the volcanic ash level that has yielded Quaternary fauna, lithic artefacts and several human remains, which gives an age of 1.81±0.05 Ma. The subcontemporaneity of Hominid presence and volcanic ash deposition makes Dmanisi the oldest prehistoric site currently known in Europe and proves human presence at the gates of Europe 1.81 Ma ago. To cite this article: H. de Lumley et al., C. R. Palevol 1 (2002) 181–189.  相似文献   

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In November 2002, during the study of the Plio-Pleistocene formations of Denizli Basin, containing significant active and fossil travertine deposits, during a visit to the Dalmersan factory, near the Kocaba? quarries, I identified a Hominid skullcap among bones retrieved during the cutting of travertine slabs. I immediately attributed this skullcap to a Homo erectus. I then handed over the study of this fossil, first to Professor John Kappelman from Texas University, then to a multidisciplinary study led by the Human Paleontology Institute in Paris.  相似文献   

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Sami Lakkis 《Hydrobiologia》1973,43(1-2):235-252
2275 samples have been collected with the Continuous Plankton Recorder of Hardy at a standard depth of 10 meteres in the English Channel and the Bay of Biscay between 1958–1965. Biological as well as statistical analyses have been carried out to provide data on annual fluctuations of 34 species of copepods and phytoplankton. Methods of analysis of variance and the correlation coefficient analysis were used for this purpose. The results are presented in the form of triangular matrices showing the annual fluctuations of species in the different areas considered and the relationship between different species in each area. These methods allowed us to define separate groups of species that could be called annual communities.

Extrait d'une thèse de Doctorat en Oceanographie biologique, soutenue à la faculté des Sciences de Paris le 19 décembre 1967. Ce travail a été subventionné par the Office of Naval Research, Department of the United States Navy en vertu du contrat No 62558-3612.

Extrait d'une thèse de Doctorat en Oceanographie biologique, soutenue à la faculté des Sciences de Paris le 19 décembre 1967. Ce travail a été subventionné par the Office of Naval Research, Department of the United States Navy en vertu du contrat No 62558-3612.  相似文献   

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ObjectiveThe treatment of lung adenocarcinomas is conditioned by the presence of certain genetic abnormalities. Certain quantitative parameters obtained from FDG PET-CT, at the voxel scale, provide tumour shape and texture characteristics and might predict their mutational status. Our objective was to determine the impact of the segmentation method in the characterization of lung adenocarcinomas in FDG PET-CT.MethodsForty-nine patients with pulmonary adenocarcinomas were retrospectively included, with their initial FDG PET-CT image. The studied tumours were big, heterogeneous and difficult to segment automatically. The automatic FLAB algorithm was used with and without manual adjustment. The parameters were extracted and compared to the ALK, PDL1, and KRAS status, in order to compare the performances of the two segmentation methods. Their performance was determined by the ROC curve method.ResultsSeveral parameters were significant to predict genetic status (AUC > 0.65). The best performing parameters were different according to the genes studied and according to the resampling methods used. The results were less dependent on resampling in automatic segmentation without manual adjustment. The best performing parameters were volume dependent parameters for segmentation with manual adjustment, and texture parameters for automatic segmentation without adjustment.ConclusionThe study of texture parameters is more efficient in automatic segmentation that is not manually adjusted, and it is advantageous to use a manual adjustment when studying volume-dependent parameters in the case of very heterogeneous tumors.  相似文献   

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Aim

Retrospective study to assess the value of fluorine-18 dihydroxyphenylalanine (18F-Dopa) positron emission tomography (PET)/computed tomography (CT) in the post-surgical follow-up of patients with history of medullary thyroid carcinoma (MTC) and biological suspicion of disease relapse. A review of the literature was also performed.

Patients and methods

Ten patients (23-71 years) with MTC previously treated by surgery were examined by at least one 18F-Dopa PET/CT. All patients presented with elevated serum calcitonin (130-9076 ng/l) and/or CEA (1.2-518 ng/ml) levels. 3D whole body PET/CT was performed 45 and 120 minutes after intravenous injection of 4 MBq/kg of 18F-Dopa. Scintigraphic images were visually interpreted. For quantitative analysis, maximum standardized uptake value (SUVmax) per focus was employed. PET results were compared with histological findings and/or with the results of all other imaging procedures.

Results

Seven patients (70%) had a positive 18F-Dopa PET/CT. Twenty-five focal tracer accumulations were described. Histopathological confirmation of metastatic disease was obtained in four of the seven patients with pathologic 18F-Dopa PET/CT. No scintigraphic abnormalities were evidenced in the three other patients, whose conventional morphological imaging procedures were also negatives. Delayed PET/CT examinations didn’t increase sensitivity. No correlation between 18F-Dopa PET/CT results and both serum calcitonin and CEA levels was achieved.

Conclusion

Our results are in accordance with the existing literature, showing the potential role of 18F-Dopa PET/CT in the clinical management of patients with history of MTC and biological suspicion of relapse during post-surgical follow-up. Prospective studies including larger patient series are necessary to confirm the future place of 18F-Dopa PET/CT in follow-up of MTC.  相似文献   

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Résumé Les relations antigéniques entre einq rickettsies pathogènes aux Invertébrés sont étudiées par agglutination. Cette comparaison met en évidence que le genreRickettsiella ne constitue pas au point de vue immunologique un ensemble homogène. On définit deux groupes sérologiques distincts:R. melolonthae, R. tipulae etR. cetonidarum appartiennent au groupe I; le groupe II est actuellement consitué parR. grylli etR. armadillidii.
Summary The antigenic relation between five rickettsiae pathogenic to Invertebrates have been studied by agglutination. This comparison shows that the genusRickettsiella does not form and homogeneous group from an immunological point of view. Two separate serological groups are defined:R. melolonthae, R. tipulae andR. cetonidarum belong to the Ist group;grylli andR. armadillidii are forming the IInd group now.


Ce travail a été réalisé en partie dans le cadre d'une convention D.R.M.E.  相似文献   

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The radionuclides 26Al and 10Be in situ produced in quartz near the ground surface by secondary cosmic rays can be used for dating the sediment burial. This paper introduces the principles, preconditions and limitations of the recently established dating method. In China its first trial application is to the site of Peking man. The weighted mean of six significant results of samples from layers 7–10 is 770 ± 80 ka. This date provides strong support to an earlier and longer human presence at the site than once estimated. This method has also been applied for the first time to two Lower Paleolithic sites in the Cher Valley, central France, Lunery “la Terre-des-Sablons” and Brinay “la Noira”. The preliminary results attribute ages of 750 ± 240 and 730 ± 210 ka to the two sites, largely consistent with the previous age estimates based on geological and geomorphological studies and on ESR dating. With its well-founded basis in physics, its independence from other dating methods and its timescale filling a “blank period” in radioisotopic dating, the 26Al/10Be burial dating will be widely applied and contribute substantially to the establishment of a reliable timescale for the earliest human occurrence and evolution in China and in Europe.  相似文献   

12.
《IRBM》2008,29(1):20-24
A computational model based on finite element method is derived to examine how the simulated time-dependent signals are related to the presence of residual fluorescence in biological media surrounding a fluorescent object. We apply a subtraction technique on recorded data when imperfect uptake of fluorescing agent into the tumor is considered. We show the limits of the subtracting method for low target: background fluorescent absorption contrast by extracting the time to reach the half maximum and analyzing the maximum of the time-resolved signals versus target depth.  相似文献   

13.
P?i studiu ú?inku Simazinu na virově nemocné rostliny bylo zji?těno, ?e dávky zБlivkového roztoku Simazinu (0,33 mg nebo 0,50 mg na jednu rostlinu), které nemají ?ádny ?kodlivý ú?inek na zdravé rostliny, usmrcují rostliny virově nemocné. Tento synergismus ú?inku Simazinu a virového onemocnění byl pozorován u rostlin tabáku onemocnělých VTM, u pta?inc? onemocnělých ?loutenkou blízkou aster yellows, na rostlinách bramboru a p?edbě?ně na rostlinách chmelu.  相似文献   

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Oögenesis and the physiological activity of the corpora allata were studied in adult females of the Egyptian locust (Anacridium aegyptium), in ovarian diapause, after electrical stimulation in vivo of the pars intercerebralis. This stimulation provokes (1) a decrease in the quantity of fuchsinophilic material present in the median neurosecretory cell bodies and in the internal cardiac tract, (2) an increase in the physiological activity of the corpora allata (measured by its chromatropic effect on larvae of Locusta), and (3) rupture of the ovarian diapause (advance of maturation of the oöcytes and oviposition by 5 months, and initiation of the ovarian cycle).In the control animals, the same electrical stimulations of various regions of the central nervous system (tritocerebrum, first ganglion of the abdominal cord) have no effect on these phenomena.In allatectomized females, electrical stimulations of the pars intercerebralis are followed by a slight growth of oöcytes, without a deposit of yellow vitellus. The diapause is not broken. Section of the allatocardiac nerves or rupture of the allatocardiac and allato-suboesophageal nervous connexions do not change the physiological state of the corpora allata. In the case of females in which the corpora allata have been disconnected, electrical stimulations of the pars intercerebralis succeed in activating the corpora allata and breaking the ovarian diapause. The aggregate of these results confirms that in locusts the control of the brain over the physiological activity of the corpora allata is above all neuroendocrine.  相似文献   

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《Médecine Nucléaire》2014,38(1):14-17
As part of an overall review on the role of PSA and other emerging biomarkers in the detection, diagnosis and treatment of prostate cancer, we present here a part of a review of the literature made by the working group Biologie de la Prostate (AFU, CNBH, SFBC, SFMN) on the use of PSA and other biomarkers in the early detection of prostate cancer with an assessment of the level of evidence.  相似文献   

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《Médecine Nucléaire》2007,31(12):656-664
PurposesThe aim of this study was to assess if the evaluation of tumoral volumes by fuzzy logic was workable for clinical use. This study was performed with patients followed up for radio-immunotherapy of non-Hodgkin's lymphomas with a comparison of the respective contributions of this quantification and Standardized Uptake Value (SUV).Materials and methodsThirty patients underwent 18F-FDG PET before treatment and then in an iterative way. The analysis of 217 lesions allowed to evaluate their volumes and SUV. The evolution of these parameters of quantification was compared.ResultsThese two quantitative parameters did not statistically differ but there were important discrepancies in some examinations. The determination of volumes was sometimes limited by tumoral localization or junction of lesions.ConclusionThis study proved the feasibility of the determination of tumoral volumes by fuzzy method in clinical use. Quantification supplemented the subjective visual analysis, which in most cases was sufficient to appreciate the progression of the disease. This quantification, usually given by the value of the SUV, could be improved by the voluminal data either in a separated way, or combining intensity and volume (total lesion glycolysis). Further work is necessary to specify the predictive value of these parameters in this particular indication.  相似文献   

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The study of the site of Kocaba?, which yielded an archaic Homo erectus skullcap, was undertaken in 2011 and 2012, at the request of Professor Mehmet Cihat Alçiçek. This interdisciplinary French–Turkish research programme comprised the geochronological, magnetostratigraphic, biochronological and paleoenvironmental study of the site and the paleoanthropological study of the skullcap itself. The association of large mammals enabled us to attribute the travertine formations bearing the skullcap to the second part of the Upper Pleistocene, and more specifically to between 1.5 and 1.2 million years, because of the disappearance or appearance of certain species. This biochronological age is confirmed by the paleomagnetism study, which places the travertines bearing the skullcap in a period of reversed polarity, underlying a normal polarity formation, which could be attributed to the Cobb Mountain paleomagnetic excursion, dated to 1,194,000 years. The dating of these fauna by the 26Al/10Be cosmogenic nuclide method by Anne-Elisabeth Lebatard yielded an age older than 1.22 Ma and more recent than 1.5 Ma. The Hominid skullcap from this formation can be attributed to a Homo erectus, slightly more evolved than those of Homo ergaster KNM-ER 3733 (1.78 Ma) and KNM-ER 15,000 (1.5 Ma), similar to that of Daka (Bouri), which is about a million years old and older than the Bodo fossil (estimated at 600,000 years) and Kabwe (between 300,000 and120,000 years). The archaic Homo erectus skullcap from Kocaba?, referred to as Denizli Man, proves that Homo erectus was already present in Anatolia, at the crossroads of Africa, Asia and Europe, a little more than 1.2 million years ago.  相似文献   

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