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291.
The function of glycerophosphate and malate-aspartate shuttles during glucose metabolism in two strains of Ehrlich ascites tumor cells was evaluated by several experimental approaches. The activities of the enzymes involved in these shuttle systems were assayed in the cytosolic and mitochondrial compartments after cell fractionation by the digitonin method. The glycerophosphate shuttle can be ruled out because of the lack of relevant enzymatic activities, and the failure of glucose to increase rotenone-inhibited respiration. Analysis of glycolytic flux in the presence of aminooxyacetate indicates that the activity of malate-aspartate shuttle may be very low. Balance studies of glucose uptake and lactate production suggest the existence of other pathways for the reoxidation of cytosolic NADH, which are acetyl-CoA dependent. Estimation of citrate synthase and ATP citrate lyase, in addition to the observed high activity of malate dehydrogenase, suggests a malate-citrate shuttle.  相似文献   
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J C Déiz  J Avila 《Biochimie》1985,67(9):1059-1062
The rat and rabbit lung isoform pattern before (fetal) and after (adult) lung maturation has been analyzed by isoelectric focusing. This pattern has been compared to that of brain tubulin at the same developmental stages. No changes in the pattern of fetal and adult lung tubulin were found. However an increase in brain tubulin heterogeneity was detected from fetal to adult stage.  相似文献   
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《Comptes Rendus Palevol》2016,15(6):745-751
Ichthyoarchaeological analyses of the freshwater fish remains from levels 19 and 20 in El Mirador cave (Atapuerca, Spain) have been conducted. Fish were always present as a source of animal protein, although their importance in the human diet was not fully exploited by people during the Neolithic on the Iberian Peninsula. Two principal goals are treated here: a taxonomic study of the fish remains and a characterization of the exploitation of this resource. The results show that the human community of El Mirador cave practiced fishing, and that fish was part of their diet and social life.  相似文献   
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《Comptes Rendus Palevol》2014,13(8):681-690
For the first time, the fossil herpetofauna from the Middle and Late Pleistocene of Scladina and Sous-Saint-Paul caves (Sclayn, Belgium) is described. The amphibians and squamate reptiles are represented by one salamander (Salamandra salamandra), three anurans (Pelodytes punctatus, Bufo bufo and Rana temporaria), two lizards (Lacerta cf. agilis and Anguis fragilis) and two snakes (Zamenis longissimus and Vipera cf. berus). The occurrence of the Parsley Frog (Pelodytes punctatus) and the Aesculapian Snake (Zamenis longissimus), which are not currently represented in Belgium, is of particular interest. Scladina also represents one of the northernmost fossil mentions for the Fire Salamander (Salamandra salamandra) although it is within its current distribution in Europe. Finally, the presence of the Adder (Vipera cf. berus) is very probably attested in Scladina whereas today this snake is infrequent and classified as endangered in Belgium.  相似文献   
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Au Maroc, la famille des Encyrtidae (Hymenoptera : Chalcidoidea) compte actuellement 46 espèces. Six genres (Acerophagus Smith, 1880, Cerchysiella Girault, 1914, Cheiloneurus Westwood, 1833, Copidosoma Ratzeburg, 1844, Epitetracnemus Girault, 1915, Tineophoctonus Ashmead, 1900) et sept espèces [Cheiloneurus elegans (Dalman, 1820), Copidosoma floridanum (Ashmead, 1900), Epitetracnemus intersectus (Fonscolombe, 1832), Habrolepis pascuorum Mercet, 1921, Metaphycus melanostomatus (Timberlake, 1916), Metaphycus castaneus (Mercet, 1921) et Tineophoctonus armatus (Ashmead, 1888)] sont signalés pour la première fois de ce pays. Les échantillonnages ont été réalisés dans trois stations d’étude au sein de la subéraie de la Maâmora au cours de deux années successives (juin 2012 à avril 2014).  相似文献   
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  1. Researchers have used multiple methods to understand spatial mapping memory used by arboreal mammals for orientation: the change-point test, measures of path tortuosity, field experiments with feeding platforms, nearest-neighbour feeding tree methods, complex calculations of travel route parameters, and theoretical models.
  2. This literature review provides details of all of these methods, highlights previous results from spatial mapping memory studies, and discusses perspectives for future studies.
  3. Previous studies have shown that various arboreal mammals, mostly in the order Primates, can memorise spatial environments using a cognitive map. Two types of maps are characterised: the topological map, based on landmarks and reused routes, and the Euclidean map, including the ability to create shortcuts by measuring distances and distinguishing between directions. Most of the studies showed that mammals do not travel randomly but, due to the difficulty of determining which spatial map is used, the use of cognitive maps remains hypothetical.
  4. When studying spatial mapping memory, data collection and analysis should account for the species’ characteristics, such as the home-range size, food preferences, and types of movements. The role of sensory cues (visual, auditory, olfactory) is crucial to understanding spatial orientation. The most relevant way to determine how arboreal mammals orientate themselves in space is by using a mix of methods: random theoretical models, collecting data in a controlled environment, measuring different parameters of travel patterns, and considering the use of sensory cues and environmental factors of the study sites.
  5. Research pertaining to spatial mapping memory in arboreal mammals and forest-dwelling mammals is important for understanding cognitive abilities in mammal species, and more studies are needed in mammals of various orders.
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