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A new assay for aminopeptidase P was established by coupling with proline iminopeptidase using Gly-Pro-chromogen (e.g. Gly-Pro-β-naphthylamide, Gly-Pro-p-nitroanilide, or .Gly-Pro-4-methyl coumarin amide) as the substrate. With each substrate, a linear relationship was established between the enzyme amounts and color development or fluorescence due to the chromogen released. This assay method did not suffer from interference by materials in culture broth. By using this assay method, aminopeptidase P was partially purified from Escherichia coli HB101 by chromatographies on DEAE-Sephadex and high performance liquid chromatography (HPLC). On the chromatogram with a DEAE-Sephadex column, two peaks of aminopeptidase P were observed and were named APP-I and APP-II. APP-I was further purified by HPLC using DEAE-5PW and Phenyl-5PW columns. Optimum pHs of APP-I and APP-II were 8.0 and 9.0, respectively. In contrast to APP-I which was stable around pH 10, APP-II was stable at pH 8 to 9. After incubation for 30 min at pH 8.0, fifty percent of the remaining activity of APP-I and APP-II were observed at 60°C and 50°C. APP-I and APP-II were activated 3-fold by the addition of 5 and 30 μm Mn2+. They were inhibited by EDTA, and reactivated by adding Mn2 +. The molecular weights of APP-I and APP-II were 350,000 and 210,000, respectively. Each enzymes released the amino terminal amino acid when proline is at the penultimate position. The velocity of hydrolysis by the enzymes was not significantly different for most X-Pro bonds (X = amino acid) of peptides except for Pro-Pro bond. APP-II hydrolyzed penta-(Pro-Pro-Gly) at a much higher rate than APP-I, suggesting the aminopeptidase P reported by Yaron and Mlynar (BBRC, 32, 658 (1968)) to be APP-II.  相似文献   

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Histological subtypes of lymphomas are important because FDG uptake is much greater in aggressive than in indolent lymphomas and this, results in lower sensitivity of PET for the staging of indolent lymphomas. Staging is especially useful when treatment is changed according to staging. Staging with imaging methods has traditionally been performed using a CT scanner and has been based on the detection of nodal enlargement, an increased number of small nodes and in the presence of extranodal masses. However, CT is limited by its poor sensitivity in the detection of extranodal sites of involvement, in the identification of tumour involvement of normal size lymph nodes and in the differentiation between malignant and inflammatory enlarged lymph nodes. The uptake of FDG detected with PET images reflects metabolic activity rather than the size of the tissue masses, localizing tumoral activity in enlarged and in normal size lymph nodes. In the literature review that compares PET with CT, PET usually indicates more lesions than CT would and PET improves sensitivity without losing specificity. However, the majority of studies report that PET, improves the staging in a relatively limited number of patients (10-20%) and may change treatment in less than 10% of patients. Diagnostic accuracy of PET may improve with the use of hybrid PET/CT systems that combine metabolic and morphological imaging, in the same scanner and without moving the patient. This is a promising technique that will overcome the limitations of both modalities and may enhance diagnostic accuracy in lymphoma patients. This hybrid equipment allows the use of PET/CT with contrast-enhanced full dose CT (a diagnostic CT) instead of carrying out PET and CT on different days.  相似文献   

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Some sediment sequences were known in the Elbe-Saale region. They enable a subdivision of the Saale complex, that is from Neumark Nord (Geisel valley), from Weimar-Ehringsdorf and Bad Kösen-Lengefeld (Saale valley). According to it, there are two interglacials between the Saalian groundmoraine (s.str.) and the Eemian. They are characterized by a strong subcontinental climatic influence, which could not be observed in the other interglacials of the Elbe-Saale region. The interglacials are connected with find horizons from the Middle Palaeolithic. They are concisely described here with their inventories.  相似文献   

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Correlation table of the different units at the oligocene-miocene boundary; paleogeographical and paleoclimatical results; discussion.  相似文献   

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Dans le Miocène moyen du Sud-Est de l'Europe on rencontretrès rarement des exemplaires fossiles de lamellibrancheslithophages, quelques-uns de ceux-ci appartenant au genre Lithophagaet d'autres au Pholas, Clavagella, Saxicava, Petricola, et Barnea.Certaines especes de Pholas et de Barnea sont rélativementsouvent rencontrees non seulement dans le Miocène moyen(etage Tortonien), mais aussi dans le Miocène supérieur(étage Sarmatien). En génèral ces espèces se rencontrent surun substrat calcaire. Å la fin du Miocène les espècesde lamellibranches fossiles lithophages disparaissent du basinde la Mer Noire, a cause que celui-ci est devenu un basin d'eaudouce. Mais, dans le temps actuel trois espèces de lamellibrancheslithophages vivent aussi dans la Mer Noire, venues dans le Quaternairede la Mer Mediterranee. C'est-à-dire: Pholas dactylusL., Barnea Candida var. pontica Mil., qui vivent sur un substratformé surtout de marnes argileuses ou de marnes calcaires.Sur un substrat de grès dures calcaire se rencontre presqueexclusivement Petricola lithophaga Retzius, sur la plateformerocheuse du sud de Constantza (Roumanie).  相似文献   

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Influence of light intensity and wavelength on the yield of free radicals in seeds of tomato and carrot.
Seeds of tomato ( Lycopersicum esculentum L. cv. Gribovsky-1180) and carrot ( Daucus carota L. cv. Santanet) were irradiated by continuous light of different wavelengths (white, blue, green, red, far-red and He-Ne laser) and different power density. Free radical output was measured using Electron Spin Resonance spectra (ESR). The dependence of the content of free radicals (FR) on the light power density was established. The yield of FR in the seeds irradiated with monochromatic light of the same power density was inversely proportional to the wavelength. The ESR spectra showed maximum absolute number of FR for white light. Successive irradiations gave cumulative effects on the output of free radicals in both directions: increase by the action of white light and decrease by the action of red and far-red light. The contact of irradiated seeds with steam decreased the amount of FR.  相似文献   

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Role of ethylene in both the synthesis of capsidiol and the susceptibility to Phytophthora capsici of pepper treated with an elicitor With inoculated plants, there is a strong increase of ethylene, specially with Phyo 636. But, with plants inoculated and treated with G5 15 the quantities of ethylene are less important than with those ones inoculated and untreated with G5 15. After contamination (and only in this case), there is capsidiol synthesis as well wit h treated plants as with untreated ones, and the quantities are not significantly different. Generally, the level of induced resistance is higher wit h Phyo 636 (genetically resistant) than with Yolo Wonder (genetically susceptible). The adjunction of ethylene precursor (ACC) to G5 15 elicitor increases induced resistance with Yolo Wonder but decreases with Phyo 636: the inverse effect is observed when using ethylene inhibitor (AVG). It is suggested that, in the interaction Pepper—Phytophthora capsia, neither ethylene production nor capsidiol synthesis can be considered as biochemical tracers of induced resistance.  相似文献   

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In the studied area, on the southern slope(«Ossa-Morena Zone) of the Sierra Morena (Spain) the Silurian and earliest Devonian (Lochkovian = approximately Gedinnian) consist of about 130 m of black, argillaceous, largely euxinic graptolitic slates, which, by the intermezzo of the dark «Limestones with Orthoceras and Scyphocrinus (late Ludlow and Pridolian), are divided into two inequal units, namely the Lower and Upper Graptolitic Slates. The occurence of 21 Graptolite zones and horizons was established, starting off with the basal Llandovery (A. acuminatus zone) and ending up with the Upper Lochkovian (M. hercynicas zone). This condensed tripartite graptolitic sequence, both lithologically and faunally, compares closely with the typical development of the Palaeotethys, as known from Thuringia, Carnic Alps, Sardinia and Northwest Africa. Certain graptolite species and details of the graptolitic succession (for instance across the Wenlock-Ludlow junction) that were hitherto known only or essentially from Thuringia, are recognized also in southern Spain.  相似文献   

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L'infraciliature ventrale est presque entièrement détruite lors de la conjugaison: la totalité des structures buccales, tous les cirres fronto-ventraux et transversaux, certains cirres caudaux. Le retour à l'état végétatif s'effectue en 2 étapes. Première Etape.–Différenciation d'un nouvel ensemble de cirres, dépourvu du cirre 1/I (selon la nomenclature de Wallengren); néoformation, à partir d'une ébauche située sur le territoire présomptif du cirre manquant, d'une partie des structures buccales (la moitié antérieure de la frange adorale de membranelles). Deuxième Etape.–Remplacement de tous les cirres par un nouvel ensemble comportant le cirre 1/I; différenciation des structures buccales manquantes (moitié postérieure de la frange adorale, ciliature parorale) Les rapports morphogénétiques entre le cirre 1/I et la ciliature parorale suggèrent que le territoire de ce “cirre paroral” est homologue des territoires stomatogènes d'autres Hypotriches tels que Kahliella et Stylonychia. SYNOPSIS. During conjugation of Euplotes, the ventral ciliature, including the entire oral apparatus, all the fronto-ventral and transverse cirri, and some of the caudal cirri, is nearly completely lost. As followed in silver-stained preparations, the redifferentiation of the ciliature proceeds in 2 steps. The first step entails differentiation of a new complement of cirri, except for cirrus 1/I (according to the nomenclature of Wallengren), and neoformation of the anterior part of the adoral zone of membranelles (AZM) from a primordium located in an area that would be expected to give rise to the missing 1/I cirrus. The 2nd step involves replacement of all the cirri, including 1/I, and completion of the oral apparatus by redifferentiation of the posterior half of the AZM and of the paroral ciliature. The spatial morphogenetic relationships between cirrus 1/I and the paroral ciliature suggest that the area of this “paroral cirrus” is homologous with the stomatogenic areas of other Hypotrichida, such as Kahliella and Stylonychia.  相似文献   

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Multiple myeloma (MM) is a malignant hemopathy characterized by a pathologic proliferation of plasmocyts in bone marrow. Detection of bone lesion is of great importance in initial extension screening and for the follow-up because it has an impact on therapeutic strategy. Plain radiographs do not have a good sensitivity for the detection of such lesions. Magnetic resonance imaging (MRI) is an interesting tool to detect diffuse bone marrow infiltration. We propose, based on the experience of our center and through a comprehensive review of the literature, to present the potential of [18F]-FDG PET/CT for the detection and the therapeutic strategy of bone lesions in MM.  相似文献   

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