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《L'Anthropologie》2021,125(5):102951
Many studies and discussions have been made on the problem of when the earliest human beings appeared in Japan. In general, hominid fossils in the latest Pleistocene are not preserved except for coralline limestone sequence in Ryukyu islands, but earlier Paleolithic tools were excavated from volcanic ash soil with a 14C age of about 30,000–35,000 yr. BP or younger at several archeological sites in almost all Japan. Recent studies, however, show a need for revision and refinement of these ages because calibration techniques have progressed from conventional to calendar ages and high-resolution oxygen isotope chronology has given a global standard sequence. Aïra-Tn tephra (AT), the most important time-marker of the Paleolithic age in Japan, was formerly dated at 21,000–22,000 yr 14C BP by conventional radiocarbon methods but was dated again at ca. 24,500 yr 14C BP by accelerated mass spectrometry radiocarbon methods. However, it has been further calibrated to a high-resolution calendar age of 30,000 cal yr. by varve chronology of lake sediments of Suigetsu of central Japan, well matched with combined date between oxygen isotope dates based and calibration from AMS radiocarbon dates. As the earliest Paleolithic tools in south Kanto are found in volcanic ash soil significantly below AT ash and above Sambe-Ikeda ash (SI, ca.46 ka), just above the oxygen isotopic stage 3.3, they are estimated to be dated slightly older than 40 ka. Palaeo-environment at that time is estimated mild to cool climate and relatively low sea level after the oxygen isotope stage 3.3. Sill land bridges between Japan islands and continents have not been formed at major straits. We have not yet obtained useful data for calibration older than ca. 45 ka. Also, correlation of oxygen isotopic fluctuation with the terrestrial sequences is incomplete in Stage 3.  相似文献   

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《Médecine Nucléaire》2019,43(5-6):381-385
AimProduction of 68Ga-radiopharmaceuticals is a rapidly growing field in France. However, operators may already be involved in other radiopharmaceutical activities. It is thus necessary to know the exposure of this new activity.Material and methodsFor passive dosimetry, a radiophotoluminescent (RPL) dosimeter, a thermoluminescent (TLD) chip, 2 TLD rings and a passive dosimeter for crystalline were used. For active dosimetry, an extremity dosimeter and a whole body dosimeter were used. This study was performed during semi-automatized production of 68Ga-investigational medicinal products. Values were normalized to 500MBq manipulated (median activity using a 1850MBq 68Ga-generator), 60 radiosynthesis (maximum enrollment ability of our center) and 2 operators. A LB123 proportional counter was used for quantification of external exposition to 10MBq 68Ge and internal exposition by inhalation was theoretically assessed. 68Ga emission attenuation by collective protection equipments was also discussed.ResultsConsidering passive dosimetry, the equivalent dose to extremities was 21.75 ± 0.34 mSv, the whole-body effective dose was 0.189 ± 0.011 mSv and the dose to crystalline was 0.925 ± 0.009 mSv. Considering active dosimetry, the equivalent dose to extremities was 8,75 ± 0.12 mSv and the whole-body effective dose was 0,088 ± 0.009 mSv. Total exposure to 68Ge was 1.75 μSv.ConclusionIn our hands, 68Ga is a directly transposable activity in radiopharmacies already equipped for 18F because of a dosimetry complying with regulatory limits and suitable radiation protection of collective equipments.  相似文献   

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Résumé Les auteurs ont isolé plus de 700 souches de bactéries lactiques à partir de raisins, de moûts, de vins de diverses origines et à différents stades de conservation. Ils étudient ici 253 souches de bacilles hétérofermentaires, dans le but d'établir une classification simple et un catalogue permettant un repérage facile des souches.Il est commode de classer les souches d'après la fermentation des pentoses, en raison de la netteté de ces tests, alors que parfois ceux appliqués à d'autres sucres ont des caractères moins tranchés. On retrouve alors la classification qui avait été déjà donnée par Vaughn, Douglas et Fornachon en 1949.Les bacilles pentoses négatifs (26 souches) forment l'espèce Lactobacillus fructivorans. Ceux qui font fermenter seulement l'arabinose (4 souches) ou seulement le xylose (155 souches) correspondent respectivement à Lactobacillus desidiosus et à Lactobacillus hilgardii. L'espèce Lactobacillus brevis comprend les bacilles pentoses positifs (68 souches).
A study of two hundred and fifty strains of lactic acid bacteria
Summary The authors have isolated more than 700 strains of lactic acid bacteria found in grapes, musts and wines of various origins and at different states of conservation. They study in this work 253 strains of heterofermentative bacilli in order to work out a classification and a catalogue allowing easy identification of the strains.It is convenient to classify the strains from the fermentation of pentoses, on account of the accuracy of these tests, tests on other sugars having sometimes less specific characters. The results are consistant with the classification already established by Vaughn, Douglas and Fornachon in 1949.Pentose negative bacilli (26 strains) constitute the species Lactobacillus fructivorans. The ones which ferment only arabinose (4 strains) or only xylose (155 strains) correspond to Lactobacillus desidiosus and Lactobacillus hilgardii. The pentose positive strains (68) belong to the species Lactobacillus brevis.
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Résumé Les levures Schizosaccharomyces possèdent, entre autres propriétés remarquables, celle de métaboliser l'acide l-malique, provoquant en anaérobiose une fermentation alcoolique: HOOC·CH2 CHOH·COOHCH3CH2OH+2CO2. Au point de vue énergétique cette fermentation ne peut satisfaire la croissance des cellules et est liée à la fermentation du sucre. La présente étude des souches de Schizosaccharomyces se trouvant dans les collections de levures est centrée sur la fermentation de l'acide l-malique.Nous avons étudié dans quelle mesure cette propriété peut servir de base à une classification de ces levures et se trouve en relation avec le milieu d'origine, suivant le concept de «classification naturelle» de Kudrjawzew. En réalité il ne saurait y avoir de distinction d'espèce fondée sur cette propriété entre les Schizos. pombe provenant de fruits à pulpe amylacée des pays tropicaux et les Schizos. acidodevoratus provenant de fruits à pulpe acide des régions tempérées, tous attaquant plus ou moins l'acide l-malique, et ces deux termes doivent être considérés comme synonymes.Certaines propriétés physiologiques ont été étudiées: intensités respiratoire et fermentative, fermentation sélective du glucose et du fructose, produits secondaires formés, besoins en facteurs de croissance, etc. Enfin, on a défini les facteurs de la fermentation de l'acide l-malique par les Schizosaccharomyces, notamment la nature des souches, les conditions de pH, etc. L'étude de fermentations associées révèle la concurrence qu'exerce sur les Schizosaccharomyces la présence des Saccharomyces et illustre la difficulté de modifier la microflore naturelle dans la fermentation d'un milieu naturel.  相似文献   

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Le déroulement de divers types de phagocytoses, et de la formation de granulomes hémocytaires a été analysé en détail en utilisant la microcinématographie image par image. Ces réactions de défense ont été reproduitesin vitro sur les systèmes hémocytaires des mollusquesHelix etZonites, et ont permis de montrer pour les bactéries (Streptococcus) les différents stades de l'englobement direct et rapide des corps bactériens, ainsi que les mouvements orientés des pseudopodes accompagnés de déplacements des cellules qui aboutissent à l'incorporation des germes. Il a été observé que des hémocytes parviennent à phagocyter même des filaments myceliens de taille importante (Metarrhizium) par un processus lent consistant en la fixation progressive de la cellule qui plie le mycelium. Enfin, toute l'évolution de la formation des granulomes multicellulaires a été suivie d'une manière ininterrompue, notamment l'attraction des premières cellules, l'afflux et la superposition de plus en plus serrée d'hémocytes en nombre croissant, jusqu'à l'arrêt de l'évolution de cette réaction. Ces résultats mettent en évidence l'acquisition par les cellules groupées autour du champignon d'une attraction nette sur d'autres hémocytes, déclenchant de leur part une réaction d'adhésion. Ils montrent enfin que l'association de la reproductionin vitro des réactions cellulaires avec la technique microcinématographique est un principe d'étude particulièrement intéressant pour suivre la dynamique des réactions de défense à l'échelle cellulaire, et l'action de substances chimiques ou d'influences microbiennes sur ces processus.  相似文献   

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《Médecine Nucléaire》2007,31(9):521-525
Thanks to breakthroughs in drug design, new kinds of treatment in oncology have been developed. These new molecules target usually a precise molecular pathway proved to be involved in the development of a malignant disease. This led to the concept of targeted therapy. Therefore, the accurate selection of patients who may experience a clinical benefit of such treatments and the way to assess the response are still challenging issues. Molecular imaging with radiolabeled compounds seemed to be a very promising tool, as for example PET with 18F FluoroDeoxyGlucose (FDG), which allows to assess and to predict the response to a tyrosine kinase inhibitors more efficiently than conventional imaging tools. FDG is only a surrogate marker of cell proliferation. The common tools (clinical and radiological assessment) are no longer sufficient to predict the clinical efficacy of these new drugs. Molecular imaging should be added in the design of clinical trials in order to detect earlier pharmacodynamic effects, to select responding patients and to provide proofs of efficacy of these non-cytotoxic compounds. Molecular imaging databases have to be created and cross-matched to tumor sample collections, providing consequently new “dynamic” pathological resources.  相似文献   

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The prostatic gland is androgen-dependent. The role of androgens in the development, function and pathology of the prostatic gland (benign hypertrophy or cancer) derives from: direct evidence, resulting from experimental models (in vitro–in vivo) or from the biological analysis of normal and pathological human prostatic tissues. These data make it possible to describe the current point of our knowledge concerning the molecular, cellular, and tissular mechanisms involved; indirect data resulting from epidemiologic and clinical studies describing the impact of androgen suppression or supplementation on the prostatic gland. At the experimental level, it is generally allowed that the growth of prostate is controlled by androgens (testosterone and its metabolites). A suitable circulating testosterone level is necessary to maintain the growth, development, differentiation and function of the prostatic gland. Bilateral orchidectomy induces programmed cellular death (apoptosis) and the gland involution; exogenic testosterone administration is then able to induce the prostatic growth up to the normal level. The same applies when an impubescent animal is treated. The response of prostate to exogenic testosterone thus does not produce a growth beyond the normal volume, which is maintained by balance between proliferation and cellular death in the presence of physiological levels of androgens. The study of the mechanisms of regulation of the prostatic growth provides a fundamental justification to the chemical and hormonal treatments used by the urologists in the treatment of prostate benign hypertophy and cancer. Within the framework of the androgenic deficit related to age, a doubt persists about a potentially harmful action of the substitute androgenic treatment on prostate.  相似文献   

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Résumé Les auteurs ont étudié 750 bactéries lactiques isolées de vins, en utilisant les tests et le système de classification de Rogosa et Sharpe. Parmi ce grand nombre de souches vingt-trois appartiennent au groupe des bacilles homolactiques et font l'objet du présent travail. Elles se répartissent de la façon suivante: 9 souches de Lactobacillus plantarum, 2 souches de Lactobacillus casei var. casei, 4 souches de Lactobacillus casei var. alactosus et 8 souches de Streptobacterium non classées, différentes des espèces précédentes.Les auteurs discutent la valcur de cette classification, lorsqu'on se place au point de vue technologique. Ils montrent qu'elle s'applique mal aux bactéries lactiques isolées de milieux fermentés acides comme le vin. Elle a peu d'intérêt pratique, car elle ne permet pas de repérer une souche et de prévoir par sa position systématique les constituants du vin que cette souche est susceptible de métaboliser.
A study of some homofermentative lactic acid bacteria isolated from wines
Summary The authors have studied 750 strains of lactic acid bacteria isolated from wines. In this study the test and classification of Rogosa and Sharpe were used. Of the strains mentioned 23 belonged to the homolactie bacteria, including 9 strains of Lactobacillus plantarum, 2 strains of Lactobacillus casei var. casei, 4 strains of Lactobacillus casei var. alactosus, and 8 strains of a non-identified Streptobacterium species.The authors discuss the value of the classification mentioned from the point of view of wine technology. They conclude that it cannot be applied in the case of lactic acid bacteria isolated from acid fermentation products such as wine. It is only of little practical interest because it does not render the identification of the strains possible, nor does it permit a prediction of the wine constituents which the strains concerned are able to metabolize.
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Tychoplanktonic and epilithic diatom samples were taken monthly during one year at 18 sites in small lowland rivers in the northern central region of Portugal. Canonical correspondence analysis was used to explore the relationships between measured environmental variables and patterns in the diatom assemblages. Conductivity, HCO3, and chemical oxygen demand (COD) were the most significant environmental variables influencing the structure of the tychoplankton and of the epilithon. Other less important variables, such as K+, Fe, N(NO3), and Na+ also explained significant (P < 0.05) amounts of variance. The ordination diagrams showed very similar distribution of the tychoplanktonic and epilithic diatom samples. At sites with similar geomorphology as in this study, it is possible to use only one of these samples for water quality evaluation. The optima and tolerances of some diatom taxa were calculated for the most influential variables. Although the diatoms showed high tolerances to some environmental parameters, it was possible to establish groups of taxa with defined and distinctive ecological preferences. Two species groups stood out depending on the alkalinity and mineralization of the water. With a moderate conductivity (> 600 μS·cm−1), alkaline pH, HCO3 concentrations equal or higher than 150 mg·l−1, the first group includes Achnanthes hungarica Grunow, Amphora pediculus (Kützing) Grunow, Bacillaria paxillifera (O. F. Müller) Hendey, Cymatopleura solea (Brébisson) W. Smith, Navicula accomoda Hustedt, Navicula lanceolata (Agardh) Ehrenberg, Navicula trivialis Lange-Bertalot, Nitzschia hungarica Grunow. In waters of lower conductivity (varying between 72 and 262 μS·cm−1) slightly acid pH (6 to 6.5) and HCO3−1 lower than 46 mg·l−1 the following species were common: Achnanthes oblongella Östrup, Achnanthes subatomoides (Hustedt) Lange-Bertalot, et Archibald, Cymbella gracilis (Ehrenberg) Kützing, Cymbella naviculiformis Auerswald, Diatoma mesodon (Ehrenberg) Kützing, and Eunotia exigua (Brébisson) Rabenhorst. Considering COD, two further groups were distinguished. At high values (> 40 mg·l−1) the following taxa were observed: Achnanthes delicatula (Kützing) Grunow, Navicula capitata Ehrenberg var. hungarica (Grunow) Ross, Nitzschia nana Grunow, Pinnularia interrupta W. Smith, Thalassiosira pseudonana Hasle & Heimdal, Thalassiosira weisflogii (Grunow) Fryxell et Hasle. For lower values than 19 mg·l−1, we found Cymbella naviculiformis Auerswald, Diatoma mesodon (Ehrenberg) Kützing, Eunotia exigua (Brébisson) Rabenhorst, Fragilaria arcus (Ehrenberg) Cleve, and Nitzschia epithemioides Grumow var. disputata (Carter) Lange-Bertalot.  相似文献   

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《Geobios》1986,19(2):179-205
The discovery of well-preserved Radiolaria yielded into a single phosphatic nodule from Carboniferous lydites of Bareilles (Hautes-Pyrénées, France) allowed the identification of ten genera and nineteen species. Four of these species are new. The separation of the fauna from the phosphatic matrix has permitted it to be studied with the scanning electron microscope and to be correlated with faunas recently described by the same process. At least, seven species are identical with middle and upper Tournaisian phosphatic nodules from the Montagne Noire (Deflandre and Deflandre-Rigaud, 1944, Deflandre, 1973b) and from Istanbul, Turkey (Holdsworth, 1973), and eight others with Visean from the «Rheinische Schiefergebirge, West Germany (Won, 1983). The author questions the age of lydites from Hautes-Pyrénées, attributed to middle to upper Tournaisian (early Mississippian).  相似文献   

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Didier Chardez 《Hydrobiologia》1968,32(1-2):271-287
Sans résumé

Deposé à la redaction le 28 décembre 1967.  相似文献   

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Subtle motor, emotional, cognitive and behavioural abnormalities are often present in apparently healthy children and adolescents who later develop schizophrenia. This suggests that some aspects of causation are established long before psychosis becomes manifest. We aim to assess the factors contributing to the development of schizophrenia focusing mainly on genetic factors, pregnancy and delivery complications, early development and scholastic performance, as well as later educational, social and health consequences. This is done by reviewing the Northern Finland 1966 Birth Cohort, its scientific activities, publications and work in progress.  相似文献   

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AimThe purpose of this study was to investigate some of the parameters likely to influence mebrofenin-99mTc hepatic clearance calculation and inter-and intra-observers reproducibility.Materials and methodsHepatic clearance (%/min m2) of 30 scintigraphies was calculated from the values of hepatic, cardiac, and total activities, according to the method recommended in the literature. We studied: 1) impact of injection–acquisition delay variations; 2) acquisition type: anterior face only (FA) or geometric mean (GM); 3) clearances calculated according to four different body surface area (BSA) formulas; 4) intra-and inter-observers reproducibility for three observers (two evaluations for each observer).Results1) Clearance differences between different studied intervals were statistically significant, more important if the studied interval was far from reference interval (150–350 secondes) and even more when the interval studied was too early (110–310 secondes). 2) There was a statistically significant difference between clearance calculated using either FA or GM datasets (0.85 %/min m2). 3) There were small but statistically significant differences for four of the clearance comparisons using different BSA formulas. 4) Despite differences in size of cardiac and hepatic regions of interest (ROI), intra-observer reproducibility of hepatic clearance was excellent for each observer. Inter-observers reproducibility was also excellent (r = 0.982).ConclusionHepatic clearance of mebrofenin-99mTc appears to be a highly reproducible method provided that acquisition and clearance calculation are standardized. It provides additionnal functional information to morphological and biological data usually performed before major hepatectomy. Thereby, the definition of a standardized protocol would enable realization of multicentric studies.  相似文献   

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The aim of the present study was to investigate the contribution of the single photon emission computed tomography/computed tomography (SPECT/CT) in cancer patients and to evaluate its ability to correctly classify indeterminate lesions on planar bone scintigraphy (PBS).MethodsFrom November 2006 to August 2007, all patients with confirmed malignancy, whose PBS showed indeterminate lesions, underwent without delay a SPECT/CT. The study included 120 patients (67 men, 53 women), with a mean age of 69 ± 12 years (range 42–96 years). The patients with obvious metastases, important pains or who did not accept the examination were excluded from the study. The location of the lesions was described either as precise, probable or indeterminate. The lesions were classified either as definitely malignant, definitely benign or indeterminate.ResultsBreast, prostate, lung and kidney neoplasms represented approximately 80% of all cancers. The PBS highlighted 267 lesions of location either as precise (n = 29), probable (n = 129) or indeterminate (n = 109), classified either as definitely malignant (n = 28), definitely benign (n = 27) or indeterminate (n = 212). The SPECT/CT revealed 440 lesions, of location either as precise (n = 353), likely (n = 39) or indeterminate (n = 48), classified either as definitely malignant (n = 84), definitely benign (n = 305) or indeterminate (n = 51). Thoracic and lumbar spine and pelvis were the locations of 79% of the scintigraphic lesions and of 88% of the osseous metastases. SPECT/CT modified the final report of 80 patients, by excluding from metastases (n = 2), by showing metastases (n = 23) and by showing the benign character of indeterminate lesions (n = 55). Moreover, 69 patients out of 120 (> 57%) had an evolution confirmed with 35 true positives, 31 true negatives, one false negative and two patients with indeterminate lesions on SPECT/CT, without osseous metastasis.ConclusionThe assessment of the indeterminate scintigraphic lesions of oncologic patients benefits from the SPECT/CT. The lesion-based analysis showed that the SPECT/CT detected more lesions (+64%) and correctly classified 88% of the detected lesions. The patient-based analysis highlighted that SPECT/CT modified the final report for more than 66% of the patients. The follow-up showed that SPECT/CT correctly classified for more than 95% of the patients.  相似文献   

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