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111.
So far, the oldest terrestrial mammal associations in Italy dates to the beginning of the Oligocene, with Anthracotheriidae being the most represented taxon. Sites from northern Italy yielded remains of the genus Anthracotherium that spread from Asia to western Europe after the Grande Coupure. A finding at Grancona, which is Priabonian in age, implies that Anthracotheriidae family reached the Italian Peninsula before the Eocene–Oligocene boundary. Thus, the dispersal of this family in northern Italy is anterior than previously believed. The fossil consists of a poorly preserved right hemi-maxilla with well-preserved P4 and M3. The shape and the size of the teeth are not compatible with the genus Anthracotherium. On the contrary, the closer affinities with the Croatian species Prominatherium dalmatinum suggest a connection between the Balkan area and the Italian peninsula and a possible new way of dispersal for this family.  相似文献   
112.
Congenital disorders of glycosylation (CDG) are a growing group of inherited metabolic disorders where enzymatic defects in the formation or processing of glycolipids and/or glycoproteins lead to variety of different diseases.  相似文献   
113.
《Médecine Nucléaire》2023,47(4):193-199
Aim of the studyIn this study, we aimed to determine the factors affecting increased glucose metabolism, which is one of the dedifferentiation mechanisms, by using [18F]FDG and [68Ga]Ga-PSMA PET/CT in patients with castration-resistant prostate cancer (CRPC).Materials and methodNinety-three patients with CRPC were included in the study. Gleason score (GS), and total PSA and free PSA levels of the patients were recorded. Patient- and organ-based evaluations were performed according to the lesion uptakes as follows: score 0: PSMA (-) FDG (-), score 1: PSMA (+) FDG (-), score 2: PSMA (+) FDG (+) (FDG < PSMA), score 3: PSMA (+) FDG (+) (FDG = PSMA), score 4: PSMA (+) FDG (+) (FDG > PSMA), and score 5: PSMA (-) FDG (+). scores 1 and 2 were classified as group 1, and scores 3 to 5 were classified as group 2.ResultsThe median age of our patients was 70 (51–88) years. Eighty-eight patients (94.6%) were PSMA-positive, 78 patients (83.8%) were FDG-positive, and 89 patients (95.6%) were or PSMA or FDG positive. When the two groups were compared in terms of patient-based parameters, the median age and GS were found to be significantly higher in group 2. ROC analyses revealed that age and GS were significant in predicting group 2.ConclusionSince glucose metabolism can increase in CRPC patients with advanced age and high GS, we recommend combining [18F]FDG PET/CT with [68Ga]Ga-PSMA PET/CT in routine clinical practice in order to identify this patient subset and refer them to additional therapies.  相似文献   
114.
Résumé L'étude du fonctionnement du cycle de l'azote dans les milieux dunaires des c?tes méditerranéennes fran?aises a conduit à analyser le comportement de l'oyat,Ammophila arenaria, au cours de son développement en réponse aux variations de l'humidité et de la teneur en nitrate du sol. Les mesures d'activité nitrate réductase et de la teneur en nitrate dans les feuilles ont été effectuées simultanément avec les mesures des teneurs en eau et en nitrate du sol. Cette plante a des activités nitrate réductase ne dépassant pas 0,27 μmoles h−1 g−1 matière fra?che, qui n'ont pu être mesuréesin vivo qu'en présence de nitrate exogène dans le milieu d'incubation. Il appara?t que la plante réduit ou accumule préférentiellement le nitrate selon que l'on se situe en période humide ou sèche. Pour des valeurs voisines ou inférieures à 2% d'humidité dans les vingt premiers centimètres de sol, l'activité nitrate réductase décro?t et des quantités importantes de nitrate s'accumulent (169 μg N.NO3.g−1 matière sèche). Dans ces conditions, le nitrate dans la solution du sol peut atteindre une concentration élevée (6 meq.l−1). Inversement, au-delà de 2% d'humidité le nitrate endogène s'épuise et l'activité nitrate réductase augmente. La régulation de l'assimilation et de l'accumulation du nitrate par l'oyat dépend de son alimentation hydrique et done des quantités de nitrate absorbées à partir de la solution du sol et véhiculées dans la sève brute.
In situ study of the influence of dune soil humidity and nitrate contents on the nitrate accumulation and reduction in marram (Ammophila arenaria L.)
Summary The search for a better understanding of the nitrogen cycle in the sand dunes of french mediterranean beaches have driven us to study the habits ofAmmophila arenaria. In this way, we have followed its responses to different soil water potentials and nitrate contents of the soil during its development. Nitrate reductase activities and nitrate contents of leaves have been measured simultaneously with water and nitrate contents of soil. This plant has a slight nitrate reduction activity, not more than 0,27 μmoles h−1 g−1 fresh matter, which could be measuredin vivo only by the addition of nitrate to the incubation media. It seems that the plant reduces or else it stores, in a preferential way the nitrate whether it is in a humid or dry period. If humidity values are near or below 2%, the marram diminishes its assimilation activity and stores important amounts of nitrate (169 μg N−NO3 .g−1 dry matter). In these conditions the nitrate can be highly concentrated in the soil solutions (6 meq.l−1). Opposite, above 2% of humidity, the nitrate reductase activity decreases and the endogenous nitrate is consumed. The regulation of the assimilation and storage of nitrate by the marram is mainly a function of the soil humidity and so, of the amount of nitrate taken from the soil solution and carried into the xylem.
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115.
The presence of adenosine receptors coupled to adenylate cyclase in cultured cardiocytes from atria and ventricles from neonatal rats is demonstrated in these studies. N-Ethylcarboxamideadenosine (NECA), l-N6-phenylisopropyladenosine (PIA), and 2-chloroadenosine (2-cl-Ado) stimulated adenylate cyclase in a concentration-dependent manner in both cultured atrial and ventricular cells. The order of potency of stimulation was NECA > PIA > 2-cl-Ado. The stimulation of adenylate cyclase by NECA was enhanced by guanine nucleotides and was blocked by 3-isobutyl-1-methylxanthine in both these cells. Other agonists such as epinephrine, norepinephrine, dopamine, F?, and forskolin were also able to stimulate adenylate cyclase, although the extent of stimulation by these agents was higher in ventricular than in atrial cells. The stimulation of adenylate cyclase by epinephrine and norepinephrine was inhibited by propranolol but not by phentolamine. On the other hand, phentolamine, propranolol, and haloperidol inhibited dopamine-stimulated adenylate cyclase activity to the same extent. Forskolin, at its maximal concentration, potentiated the stimulatory effect of epinephrine, norepinephrine, and dopamine on adenylate cyclase in both atrial and ventricular cardiocytes, but the interaction of NECA with epinephrine, norepinephrine, or dopamine was different in atrial and ventricular cells. The stimulation by an optimal concentration of NECA was additive with maximal stimulation by the catecholamines in atrial cells but not in ventricular cells. The data suggest the existence of adenosine “Ra” and catecholamine receptors in cultured atrial and ventricular cardiocytes. It can be postulated that adenosine in addition to its role as a potent vasodilator might regulate cardiac performance through its interaction with “Ra” receptors associated with adenylate cyclase. The difference in the mode of interaction of adenosine with catecholamines in atrial and ventricular cells suggests that the mechanism by which these agents activate adenylate cyclase may be different in these cells.  相似文献   
116.
Two Lower Bajocian new localities, with many silicified bryozoans and brachiopods have been discovered in Causses (France): Saint-Rome-de-Cernon (Aveyron) and Mende (Lozère). The study of the faunas allows to increase the anterior knowledges supplied by the study of localities in the South of Causses (neighbourhood of Alzon and Sumène = North of the Seuil sud-caussenard).The interest is, at first, the distance between the localities: Mende in the North, Saint-Rome-de-Cernon in the West. Moreover, in the second, well-preserved faunas were fossilized without transport. Bryozoans and brachiopods are very numerous. Large and complete bryozoan colonies have been get out by action of HCl. Fine internal structures like rhynchonellid Nannirhynchia or like thecidean transversarium and hemispondylium have been studied. At last, observations and paleoecological hypothesis are drawn, likewise comparison between three localities or locality-groups known in the Causses basin.The fauna from Saint-Rome-de-Cernon is biocoenosis, the substratum was soft, the hydrodynamism low and the depth, according to lamellibranchs, about 200 meters. The beds with bryozoans and small brachiopods contain a fauna with two predominant bryozoan species: Ceriocava straminea and Mesenteripora wrighti. These two species could built large colonies, in spite of fine granulometry of the sedimentary bottom. These colonies provided supports to less adapted bryozoans, to thecidids and to lamellibranch Lopha. The beds with terebratulids and bryozoans contain lesser bryozoans and thecidids. Terebratulids are the main group and are fixed with their peduncle to organic support above the irregular deposits. Beside these benthic animals, the rhynchonellid Nannirhynchia campestriensis is epibiontic on gorgonids or epiphytic on floating sea-weeds.On the contrary, all fossils from Mende have been more or less carried, excepted large sponges perhaps. The most numerous bryozoans (Ceriocava straminea, Mesenteripora wrighti) and numerous Lenticulines (Foraminifera) lived on hard bottom with moving water in community with crinoids. It is possible that a smaller part of bryozoans, requiring lower hydrodynamism, lived, either in sheltered parts of the crinoid community or closer to the sedimentation zone. Thecidids were fixed either on bryozoans in crinoid communities or on shelly remains and on bryozoans nearer to the sedimentation zone. Like in Saint-Rome-de-Cernon, Nannirhynchia campestriensis was epibiontic, or epiphytic, or both.In comparison with the whole localities from the Seuil sud-caussenard, we notice the simplicity of Saint-Rome-de-Cernon and Mende. The localities from the Seuil sud-caussenard were assemblages proceeding from 2 or 3 biotops. On the contrary, at Saint-Rome-de-Cernon we have a biocoenosis and at Mende a thanatocoenosis supplied by one biotop almost.  相似文献   
117.
Fructose bisphosphatase catalyzes a key reaction of gluconeogenesis. We have cloned the fructose bisphosphatase (FBP1) structural gene from Saccharomyces cerevisiae by screening a genomic library for complementation of an Escherichia coli fbp deletion mutation. The cloned DNA expresses in E. coli a fructose bisphosphatase activity which is precipitable with antibodies specific for the yeast enzyme and is sensitive to inhibition by fructose 2,6-bisphosphate. Evidence is presented demonstrating that the entire gene, including all cis-acting regulatory sequences, has been cloned. A substitution mutation that disrupts FBP1 was incorporated into the yeast genome by transplacement to construct a fructose bisphosphatase null mutation. The fbp1 mutant strain is a hexose auxotroph, otherwise growing normally. Southern blot hybridization analysis confirmed the structure of the transplacement and demonstrated that FBP1 is present in single copy in the haploid genome. Northern blot hybridization analysis revealed an mRNA of about 1350 nucleotides, whose presence was repressible by glucose in the medium. Fructose bisphosphatase activity was not greatly overproduced when the FBP1 gene was present on a multicopy vector in yeast.  相似文献   
118.
Peter M. Galton 《Geobios》1985,18(5):671-676
The femur of the anchisaurid (= plateosaurid) prosauropoddinosaur Euskelosaurus browniiHuxley, 1866 from the lower Elliot Formation (Upper Triassic) of South Africa is sigmoidal in posterior view with the fourth trochanter well removed from the medial edge. The sympatric Melanorosaurus readiHaughton, 1924 is not a junior synonym of Euskelosaurus brownii because the femur is straight in posterior view with the fourth trochanter close to the medial edge. In addition to Melanorosaurus, the Melanorosauridae Huene, 1929 includes Camelotia borealis nov. gen. and nov. sp. from the Upper Triassic of England, Riojasaurus incertusBonaparte, 1969 from the Upper Triassic of Argentina, and possibly some of the posteranial material referred to the? rauisuchian the codontian Sinosaurus triassicusYoung, 1948 from the Lower Jurassic of China.  相似文献   
119.
The glycosylation and immunoreactivity of an estrogen regulated glycoprotein secreted by breast cancer cells in culture and defined by its molecular mass (52 000-Mr protein) have been studied indirectly using an inhibitor of glycosylation and specific endoglycosidases. The protein and its deglycosylated forms were immunoprecipitated with specific monoclonal antibodies to the 52 000-Mr protein and analyzed by SDS polyacrylamide gel electrophoresis. The 52 000-Mr protein was intensely labelled by [3H] mannose or [35S] methionine. Tunicamycin treatment of the cells, endoglycosidase H or endoglycosidase F digestion of conditioned media, gave two identical deglycosylated forms of 50 000-Mr and 48 000-Mr which remained immunoreactive. The 48 000-Mr protein, in contrast to the 52 000 and 50 000-Mr proteins, was unable to bind concanavalin A. The 52 000-Mr protein was resolved into five spots of decreasing pI on two-dimensional gels following immunoprecipitation. Endoglycosidase H treatment decreased the molecular weight and reduced the intensity of spots of lower pI, suggesting that the N-glycosylated chains contain acidic molecules. We conclude that: The 52 000-Mr secreted protein contains at least two high mannose or hybrid N-glycosylated chains of approximately 2,000 molecular weight corresponding to 8% of the mass of the 52 000-Mr protein. The two types of monoclonal antibodies (site 1 and 2) raised against the 52 000-Mr glycoprotein are still able to recognize the 48 000-Mr N-deglycosylated form indicating that they do not interact with the N-glycosylated moiety of the molecule.  相似文献   
120.
The soil macrofauna of a pure beech (PS) and a mixed beech-hornbeam (MS) stand was recorded using a sample design spatially explicit at stand level. Humic epipedon morphological and chemical properties, relative irradiance, soil bulk density, and the specific composition of the litter in MS were also investigated. The taxonomic diversity is nearly similar on both sites, but the average by sample is greater under PS. The main factors controlling soil macrofauna spatial variability were: litter quality under MS and humus form activity under PS. These results suggest a distal control (i.e. external to humic epipedon) of macrofauna spatial variability when the litter quality is variable and a proximal control (i.e. internal to humic epipedon) when it is uniform at the spatial scale of the study.  相似文献   
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